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A new method for diagnosing and distinguishing magma mixing and overpressure events using chemical variations… Wilson, Heather Anne 2010

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A NEW METHOD FOR DIAGNOSING AND DISTINGUISHING MAGMA MIXING AND OVERPRESSURE EVENTS USING CHEMICAL VARIATIONS IN PLAGIOCLASE by HEATHER ANNE WILSON B.Sc., University of Calgary, 2006  A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in The Faculty of Graduate Studies (Geology)  THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver)  September 2010 © Heather Anne Wilson, 2010  ABSTRACT Striking textural and petrologic evidence for mixing of basalt into silicic melts occurs in volcanic arc settings worldwide. These textures (e.g. mingled/banded pumices, inclusions), along with chemical signatures of mixing (e.g. zoning in solid solution minerals) found in many eruption products, support a popular hypothesis that magma mixing can trigger explosive eruptions through a variety of possible mechanisms. However, rigorous observational constraints on the nature of the underlying thermal and mechanical processes remain elusive. A method is developed based on Nomarski differential interferometry to image and quantitatively characterise quasi-periodic zoning in plagioclase at very high spatial resolution. Applied to individual crystals, variations in zoning with crystallographic direction confirm experimental measurements of anisotropic diffusivities for Ca2+Al3+ and Na+Si4+. When applied to the AD 1315 Kaharoa eruption of Tarawera Volcano, Taupo Volcanic Zone, New Zealand, periodic zoning at scale lengths of 3.1–12.4 µm is consistent with quasi-periodic convective motions within the magma chamber acting on timescales of 39 days to 1.8 years prior to eruption. The structure of the zoning is inconsistent with a single large basalt injection causing eruption. Rather, this eruptive episode may have been preceded by several small volume basaltic inputs, consistent with observations from mafic-silicic layered intrusions.  ii  PREFACE The main chapter of this thesis (Chapter 2) is a manuscript prepared for submission to an international geoscience journal under the same title as this thesis, ‘A new method for diagnosing and distinguishing magma mixing and overpressure events using chemical variations in plagioclase’. I am to be the first author of this paper and my co-author is A. M. Jellinek. This research presents the approach that I have developed for classification and characterisation of zoning in volcanic plagioclase crystals. This method is applied to two deposits from the 1315 explosive Kaharoa eruption of Tarawera Volcano, Taupo Volcanic Zone, New Zealand. I discuss the dynamical implications for the pre-eruptive Kaharoa magma chamber implied from timescales recovered from zoning in the plagioclase populations. A.M. Jellinek identified the research program and provided H.A. Wilson with an initial design. A.M. Jellinek collected some samples in January 2006. H.A. Wilson collected more samples in December 2006. H.A. Wilson modified the design of the research program, prepared all samples and collected all analytical data. Analyses of the data were conducted by H.A. Wilson after helpful discussions with A.M. Jellinek. The manuscript was written by H.A. Wilson, with reviews and editing by A.M. Jellinek.  iii  TABLE OF CONTENTS ABSTRACT ...................................................................................................................ii PREFACE......................................................................................................................iii TABLE OF CONTENTS ...............................................................................................iv LIST OF TABLES .........................................................................................................vi LIST OF FIGURES.......................................................................................................vii ACKNOWLEDGEMENTS..........................................................................................viii CHAPTER 1: Introduction ............................................................................................. 1 1.1. Context.............................................................................................................. 1 1.2. Previous studies ................................................................................................. 2 1.2.1. Characterising zoning in plagioclase crystals............................................... 2 1.2.2. Correlations among plagioclase crystals...................................................... 5 1.2.3. Mafic and silicic interactions....................................................................... 7 1.3. Goals and approach............................................................................................ 8 CHAPTER 2: A new method for diagnosing and distinguishing magma mixing and overpressure events using chemical variations in plagioclase......................................... 13 2.1 Introduction...................................................................................................... 13 2.2. Geology of the Kaharoa deposit and evidence for mixing ................................ 23 2.3. Methodology ................................................................................................... 26 2.3.1. Sample preparation ................................................................................... 27 2.3.1.1. Crystal selection, mounting and orientation ....................................... 27 2.3.2. Methods for characterisation of zoning: .................................................... 30 2.3.2.1. Backscattered Electron (BSE) imaging............................................... 30 2.3.2.2. Electron Microprobe Analyses (EMPA) ............................................. 31 2.3.2.3. Nomarski Differential Interference Contrast (NDIC) imaging............. 32 2.3.3. Spectral analyses....................................................................................... 32 2.4. Results............................................................................................................. 33 2.4.1. Textural and chemical characterisation...................................................... 33 2.4.2. Spectral analysis ....................................................................................... 45 2.4.2.1. Comparison of spectral methods......................................................... 45 2.4.2.2. Comparison of EMPA, BSE, and NDIC profiles ................................ 47 2.5. Discussion ....................................................................................................... 51 2.5.1. Oscillatory zoning: the basic state of the H and Hpdc magma and uncertainties .......................................................................................................... 51 2.5.2. Variations in wavelengths with crystallographic direction – a natural diffusion experiment.............................................................................................. 55 2.5.3. Oscillatory zoning and resorbtion: Potential departures from the basic state 59 2.5.4. Comparison with published work.............................................................. 62 2.5.5. Summary: Applications to Kaharoa and other eruptions ............................ 65 2.5.6. Caveats with the method ........................................................................... 67 2.6. Conclusions and future work............................................................................ 69 CHAPTER 3: Concluding remarks............................................................................... 71 REFERENCES ............................................................................................................. 73 APPENDIX A: Sample location map ........................................................................... 84  iv  APPENDIX B: Sample inventory................................................................................. 85 APPENDIX C: Crystal indexing .................................................................................. 88 APPENDIX D: Crystal inventory................................................................................. 89 APPENDIX E: Sample preparation and polishing ........................................................ 95 APPENDIX F: Electron microprobe analysis data ........................................................ 96 APPENDIX G: Backscattered electron images........................................................... 132 APPENDIX H: Nomarski differential interference contrast images ............................ 150 APPENDIX I: Preparation of images for image analysis ............................................ 165 APPENDIX J: Greyscale traverses of NDIC images................................................... 166 APPENDIX K: MatLab codes.................................................................................... 169 Nomarski image analysis......................................................................................... 169 BSE image analysis................................................................................................. 180 EMPA analysis........................................................................................................ 191 Confidence intervals................................................................................................ 194 APPENDIX L: Spectra............................................................................................... 196 APPENDIX M: Confidence intervals for the Welch spectral estimation method......... 199 APPENDIX N: Trace element data............................................................................. 201  v  LIST OF TABLES Table 1. Textural/compositional groupings of plagioclase crystals................................ 36 Table A1. Sample inventory. ........................................................................................ 85 Table A2. Crystal inventory for samples HW0604 and HW0607.................................. 90 Table A3. Electron micoprobe analysis data ................................................................. 96  vi  LIST OF FIGURES Figure 1. Photographs of a plagioclase crystal that shows Type I and Type II zoning. .... 4 Figure 2. Maps of the Tarawera Volcanic Complex, New Zealand ............................... 10 Figure 3. Stratigraphic section of the south-east sector Kaharoa eruptives. ................... 11 Figure 4. Photograph of a mingled juvenile clast from the Hpdc deposit....................... 14 Figure 5. Plot of total alkali versus silica for Kaharoa eruptives.................................... 15 Figure 6. Diagram of a simplified convecting magma chamber..................................... 17 Figure 7. Graph of the plagioclase feldspar solid solution............................................. 19 Figure 8. Flowchart of the methodology developed and implemented in this thesis....... 28 Figure 9. Graph of the size distribution of crystals from the H-fall and Hpdc samples .. 29 Figure 10. Graph of the relative frequencies of the various textural/compositional groupings for each of H-fall and Hpdc samples...................................................... 35 Figure 11. Crystals with 'Large variation' in anorthite content....................................... 37 Figure 12. Crystals with 'Small variation' in anorthite content....................................... 41 Figure 13. Plots of normalised power spectra showing different spectral methods. ....... 46 Figure 14. Plots of spectra computed from various analytical techniques performed on a single crystal. ........................................................................................................ 48 Figure 15. Plots of spectra from 'Small variation' crystals. ............................................ 53 Figure 16. Plots of spectra computed from zoning in two directions. ............................ 56 Figure 17. Graph of δA/δB for peaks in Figure 16.......................................................... 58 Figure 18. Photograph and plots of spectra from a NDIC image of a plagioclase crystal with parallel and periodic zoning on either side of a major resorbtion surface. ....... 60 Figure A1. Map of the Tarawera Volcanic Complex, New Zealand with all sample locations. ............................................................................................................... 84 Figure A2. Backscattered electron images of crystals from HW0604.......................... 133 Figure A3. Backscattered electron images of crystals from HW0607.......................... 142 Figure A4. Nomarski differential interference contrast images from HW0604............ 151 Figure A5. Nomarski differential interference contrast images from HW0607............ 159 Figure A6. Graphs of greyscale traverses across NDIC images................................... 166 Figure A7. Graphs of spectra computed from NDIC greyscale profiles....................... 196 Figure A8. Plots of confidence intervals using Welch spectral methods...................... 200  vii  ACKNOWLEDGEMENTS Mark, I would like to thank you for your enthusiasm and kind words of support throughout this process. Kelly, thank you for welcoming me as one of your own students and allowing access to your lab and expertise, discussions with you are always thoughtprovoking. Catherine, I’ve appreciated some of the conversations that we have had along the way. Jim, thank you for letting me use the PCIGR lab facility for sample preparation and helpful discussions throughout. Lori, thank you for introducing me to EBSD and instructing me in appropriate sample polishing techniques. Mati, thank you for all of your help, training, and humour using the carbon coater, SEM, BSE, and electron probe. Ben, your input on this project really helped to get it started, thank you. Jim, Chad, and Heather, thank you for your kind hospitality in New Zealand and field support. James, thank you for your very thorough review of this document, this text has benefited greatly! Khodge and Abain, you’ve made this experience a lot more fun. I look forward to seeing your faces in the lab everyday and enjoy the distractions that ensue. Guillaume and Julien, thanks for reading through my thesis and offering helpful suggestions en route to finishing. Terry, thank you for your continued interest in whatever I happen to be working on, use of your encyclopedic reference collection, and most of all your friendship and support. It’s so nice to see a friendly and familiar face around here. Matt, Krista, Antoine, you’ve been my family in Vancouver. I love you. Mom, Dad, Julia, Laura, I love you too. Thanks for your patience, I promise I’ll graduate sometime soon. Financial support for this M.Sc. was provided in part by an NSERC PGS-M Scholarship and an Egil H. Lorntzsen Scholarship (EOS, UBC). The operational costs viii  for this research were funded with support from a Royal Society of New Zealand Marsden Grant, the Natural Sciences and Engineering Research Council (NSERC) and the Canadian Institute for Advanced Research (CIFAR).  ix  CHAPTER 1: Introduction 1.1.  Context On the basis of extensive field, petrologic and modeling studies of primarily arc  volcanoes (e.g. Sparks et al., 1977; Gerlach and Grove, 1982; Pallister et al., 1992; Venezky and Rutherford, 1997; Wolf and Eicheberger, 1997; Murphy et al, 2000), it has long been recognized that the injection of basalts into silicic magma chambers in the shallow crust may cause them to erupt explosively (Sparks et al., 1977; Eichelberger, 1980; Gerlach and Grove, 1982; Bacon, 1986; Pallister et al., 1992; Venezky and Rutherford, 1997; Wolf and Eichelberger, 1997; Murphy et al., 2000). However, the nature and mechanics of the underlying thermal and mechanical processes remain a topic of discussion (e.g. Sparks et al., 1977; Sparks and Marshall, 1986; Mahood, 1990; Pallister et al., 1992; Snyder and Tait, 1995; Jellinek and Kerr, 1999; Snyder, 2000; Couch et al., 2001). Key constraints are currently missing from this debate, and include quantitative observational data related to questions such as: 1) Are these explosive eruptions driven by single catastrophic injection or are they the result of multiple smaller injections, as is suggested by studies of mafic-silicic layered intrusions around the world (i.e. analogous fossil magma chambers) (e.g. Wiebe and Collins, 1998 and references therein)? 2) To what extent are these eruptions preceded by mechanical mixing of the injected and resident magmas? 3) To what extent are these eruptions preceded by enhanced thermal mixing (with or without mechanical mixing)?  1  1.2.  Previous studies Many studies have examined zoning in plagioclase crystals (e.g. Greenwood and  McTaggart, 1957; Bottinga et al., 1966; Anderson, 1984; Pearce and Kolisnik, 1990; Pearce, 1994; Ginibre et al., 2002) and more have cited dramatic changes in zoning character to build a story about magma mixing (e.g. Stamatelopoulou-Seymour et al., 1990; Singer et al., 1995; Clynne et al., 1999; Tepley III et al., 2000; Couch et al., 2001; Izbekov et al., 2002). However, there are problems with how to characterise and compare zoning within and between crystals (Wallace and Bergantz 2002, 2004, 2005), as well as problems with how two magmas of differing composition, temperature and density can physically mix. In this section, I will present some of the past work that has helped to build the methodology that is described in the rest of this thesis.  1.2.1. Characterising zoning in plagioclase crystals One way to identify, classify, and interrogate magma chamber processes, leading to a given eruption, is through detailed analyses of the spatial-chemical variations in plagioclase crystals growing in the magma at the time of eruption (e.g. Armienti et al., 1994; Clynne, 1999; Tepley et al., 2000; Bundy and Cashman, 2001). Plagioclase feldspar is composed of a mixture (i.e. a solid solution) of albite (NaAlSi3O8) and anorthite (CaAl2Si2O8) components with relative proportions of endmembers that are sensitive to changes in intensive parameters such as temperature, pressure, water content, and melt composition (e.g. Yoder et al., 1957; Lofgren, 1980; Donaldson, 1985; Tsuchiyama, 1985; Housh and Luhr, 1991; Pearce, 1994; Dresen et al., 1996; Couch, 2  2003). Plagioclase commonly displays two types of zoning (Figure 1), distinguished by both the magnitude of chemical change and the distance over which the change occurs. In plagioclase crystals, “Type I” zoning, or oscillatory zoning, is characterised by 1-3 mol % variations in anorthite (An) content, occurring over widths of 1-100 µm (Pearce and Kolisnik, 1990). “Type II” zoning, or stepped zoning, is described by > 4 mol % changes in anorthite content, occurring over distances of > 50 µm (Bottinga et al., 1966; Allègre et al., 1981; Pearce and Kolisnik, 1990; Pearce, 1994; L’Heureux and Fowler, 1996; Fowler et al., 2002), and is interpreted to result from variations in intensive parameters and/or the melt composition (e.g. Couch, 2003; Donaldson, 1985; Dresen et al., 1996; Housh and Luhr, 1991; Lofgren, 1980; Pearce, 1994; Tsuchiyama, 1985; Yoder et al., 1957). Studies of plagioclase growth (e.g. Lofgren, 1980; Cashman, 1992; Armienti et al., 1994; Dresen et al., 1996; Philpotts and Carroll, 1996; Couch, 2003) and dissolution (Tsuchiyama, 1985; Donaldson, 1985; Sisson and Grove, 1993) help to decipher specific textures (e.g. zoning types, resorbtion surfaces) found in individual crystals resulting from the aforementioned factors. Ginibre et al. (2002) examined single plagioclase crystals from two volcanic deposits. They used accumulated backscattered electron images (BSE) to identify, at high resolution, two types of zoning that were previously grouped into the term “oscillatory zoning”: saw-tooth patterns with resorbtion (STR) and low amplitude oscillations (LAO). They describe STR as repeated, normally zoned growth layers that are separated by wavy boundaries and followed by an increase in mol % An. LAO are defined as faint repeated oscillations, with amplitudes of ≤2 mol % An and ≤1-5 µm in length. They conclude that the STR, which range in size from 5-10 µm, are not true  3  Figure 1. Photographs of a plagioclase crystal that shows Type I and Type II zoning.  4  ‘oscillations’ (kinetically controlled within a crystal-melt interface boundary layer) because they are followed by resorbtion surfaces. These resorbtion surfaces are much more common than reported, implying that there are many more dissolution events than previously recognized and this type of zoning is probably related to magma chamber dynamics. The LAO resemble the small scale zoning found in experimentally grown plagioclase (Lofgren, 1980) and may be kinetically controlled.  1.2.2. Correlations among plagioclase crystals Early studies attempting to make correlations between plagioclase crystals (Greenwood and McTaggart, 1957; Wiebe, 1968; Anderson, 1983) measured compositions across crystals using traditional petrographic techniques (e.g. the Rittmann zone method (Emmons, 1943)). Then, using both the forms and values of anorthite versus position curves, Greenwood and McTaggart (1957) and Wiebe (1968) attempted to qualitatively match crystals by stretching the curves. They assume that crystals growing in similar environments are likely to develop nearly identical zoning profiles and, those growing in dissimilar environments will grow dissimilar zoning. The methods of these authors were not so different to more recent studies by Wallace and Bergantz (2002, 2004, 2005). Wallace and Bergantz (2002) investigate wavelet-based correlation of zoned crystals, and how this method could be used to track crystals participating in a mixing  5  event. Their method is used primarily to interpret and track changes in Type II zoning (3-100 µm, up to 10s of mol % An) (Pearce and Kolisnik, 1990). They apply the wavelet transform, with a scaling function (scale to wavelength relationship), to near ‘ideal cut sections’ (Pearce, 1984) in thin sections. This method uses the wavelet transform to characterise the ‘form’ of the zoning, but restricts the final wavelet matrix to zoning with a few wavelengths of interest. From there, they apply correlation and cluster analyses to develop a ‘mixing phylogeny’, relating the crystals in a thin section to each other with varying degrees of shared growth history. This method was developed for rocks that were mechanically connected, (e.g. lavas) to assess the particle paths of the crystals, modes of shared transport, and dispersal mechanisms. Wallace and Bergantz (2004) further explore correlation techniques for determining shared histories of crystals within a thin section. This study focuses on making correlations between crystals with non-ideally cut sections, which result in zoning profiles that are off-centre (crystals are not oriented at 90° to the thin section surface and are stretched) and/or truncated (the thin section does not penetrate the core region of the crystal, and therefore does not record the entire growth history). They use Monte Carlo experiments of synthetic profiles to experiment with two normalisation routines (Fourier-based and adaptive) and two correlation techniques (wavelet-based and standard). Normalisation is used to account for differences in crystal profile length due to stretching and truncation, whereas correlation is a measure of the similarity between two profiles. They find that the number of profiles needed to resolve populations of crystals is more dependent on the normalisation routine than the correlation technique (i.e. it is more important to have ideal profiles than the ‘right’ method for correlation).  6  Wallace and Bergantz (2005) present shared characteristic diagrams (SCD) as an organizational framework for deciphering relationships between crystal populations with Type II zoning as a continuation of their earlier work. They use this framework to make correlations between crystals and construct phylogeny diagrams.  1.2.3. Mafic and silicic interactions As discussed above, Type II zoning in plagioclase crystals is attributed to changes in temperature, pressure, water content and of the melt composition. Of these, plagioclase growth is particularly sensitive to changes in temperature and water content, both of which can occur with differing magma compositions. As a result, Type II zoning in plagioclase is commonly attributed to magma mixing (or at least crystal interaction), between a rhyolite (or other silicic melt) and a basaltic intrusion (or other mafic melt). Rhyolites and basalts are commonly found in close proximity in both volcanic deposits (e.g., Medicine Lake Highland volcanics (Gerlach and Grove, 1982); Pinatubo (Pallister et al., 1992), Dikii Greben’ Volcano, Kamchatka (Bindeman and Bailey, 1994), Lassen Peak (Clynne, 1999), El Chichon (Tepley et al., 2000), Fish Canyon (Bachmann et al., 2002), and Tarawera (Leonard et al., 2002)) and plutonic environments (e.g., Aztec Wash (Falkner et al., 1995; Miller and Miller, 2002), Burnett Inlet intrusive complex (Lindline et al., 2004), Coastal Maine Magmatic Province (Wiebe, 1993; Wiebe and Collins, 1998), Halfmoon Pluton (Turnbull et al., 2010), Kameruka Suite Plutons (Collins et al., 2006), Pyramid Peak (Wiebe et al., 2002), Searchlight Pluton (Bachl et al., 2001), and Tarçouate Laccolith (Pons et al., 2006)) within arc settings, but there is difficulty in  7  tying observations between the two rock types and their petrogenesis (see Bachmann et al., 2007 and references therein). Volcanic deposits may represent the early and more active stages of magmatism within an arc (e.g. Bachmann et al., 2007), whereas plutons and batholiths may represent the late, time-integrated product of magmatism (e.g. Wiebe et al., 2002; Harper et al., 2004). Basalt is commonly observed as inclusions, enclaves and mingled/banded structures in silicic volcanic rocks. These deposits may appear to be homogeneous at large scales (metres to the size of the magma chamber), but typically have heterogeneity at small scales (i.e. crystal to enclave scales) (e.g. Bachmann et al., 2002). Composite plutons (those with silicic and mafic inputs) commonly have enclaves, basaltic layers, and mingled textures (e.g. Wiebe and Collins, 1998). These observations have led to a range of rejuvenation models for pre-eruption magma chambers, from those with thermal and mechanical mixing of rhyolite and basalt (e.g., Sparks and Marshall, 1986; Turner and Campbell, 1986; Snyder and Tait, 1996 ; Jellinek and Kerr, 1999; Snyder, 2000) to those with layered structures and only thermal interaction between contrasting compositions (e.g. Irvine, 1970; Kouchi and Sunagawa, 1985). Still other models for producing mixing textures describe ‘forced convection’, a forced mixing of differing compositions in the conduit during eruption (e.g., Kouchi and Sunagawa, 1985; Koyaguchi and Blake, 1989).  1.3.  Goals and approach To address the questions raised above (1.1) requires a way in which to identify the  action of specific processes in the magma chamber, as well as the time scales over which  8  they act in geological data. To this end, this thesis focuses on the development of a method for interrogating the thermo-chemical regime of a pre-eruptive magma chamber through a careful quantitative characterisation of the character and structure of chemical zoning found in plagioclase crystals. I build upon the work of Ginibre et al. (2002), Wallace and Bergantz (2002, 2004, 2005), and others by combining high-resolution chemical data acquired through electron microprobe analyses, and backscattered electron images with important textural information revealed by Nomarski differential interference contrast imaging. This technique is applied in a statistically meaningful way to the quasi-periodic zoning found in two populations of plagioclase crystals. These crystals are recovered from the AD 1315 Kaharoa eruption, Tarawera Volcano, New Zealand (Figure 2), an eruption supposedly caused by a magma mixing event (Leonard et al., 2002; Nairn et al., 2004). I will show that zoning in these crystals imply that quasi-periodic dynamics occurring over time scales of 39 days to 1.8 years were a major feature of the preeruptive magma chamber. I discuss these dynamics in terms of the magma chamber convective regime. Evidence for interaction with an injected basalt is only found in a only small number of crystals as large changes in anorthite content. This contribution is the first to rigorously identify a range of dynamical time scales and provides a structure for others to follow in evaluating similar deposits. This thesis has been written in manuscript form, and as such most of the associated data is presented at the end in appendices. Appendix A, Figure A1 is a map of all the samples taken from the H-fall and Hpdc stratigraphic level (Figure 3). The GPS locations and sample numbers, along with other information related to prepared samples  9  Figure 2. Maps of the Tarawera Volcanic Complex, New Zealand  10  Figure 3. Stratigraphic section of the south-east sector Kaharoa eruptives.  11  are listed in Appendix B, the sample inventory. Appendix C outlines how individual crystals from each of HW0604 and HW0607 samples have been indexed. Appendix D is the crystal inventory, and lists the textural zoning groups that I have assigned crystals to, as well as all analyses performed on individual crystals. Appendix E outlines the method that I used to prepare the sample pucks for analyses. Appendix F contains all electron microprobe analyses. Appendices G and H contain the BSE and NDIC images, respectively. Analyses performed are indicated on the BSE images. Appendix I briefly explains how images were prepared for image analysis. Appendix J shows all of the greyscale traverses collected from the NDIC images. Appendix K contains all of the MatLab™ codes that I used to analyse the greyscale profiles and compute spectra. Appendix L has all of the spectra that were computed for the NDIC greyscale profiles. Appendix M contains confidence interval calculations for the Welch spectral estimation method. Appendix N contains the trace element data that I collected under the supervision of Dr. Cin-Ty Lee at Rice University in Houston, Texas.  12  CHAPTER 2: A new method for diagnosing and distinguishing magma mixing and overpressure events using chemical variations in plagioclase1 2.1  Introduction Varied and widely-recognized textural (e.g. Sparks et al., 1977; Gerlach and  Grove, 1982; Pallister et al., 1992; Venezky and Rutherford, 1997; Wolf and Eicheberger, 1997; Murphy et al, 2000), mineral chemical (e.g. Sakuyama, 1981; Clynne, 1999; Tepley III et al., 2000) and bulk chemical (e.g. Tefend et al., 2007) observations from samples of erupted pumice support a popular picture that the intrusion, mingling, and mixing of hot basaltic magmas into silicic magma chambers often precedes and may cause (Sparks et al., 1977; Eichelberger, 1980; Gerlach and Grove, 1982; Bacon, 1986; Pallister et al., 1992; Venezky and Rutherford, 1997; Wolf and Eichelberger, 1997; Murphy et al., 2000) explosive eruptions in arc and continental settings. The AD 1315 Kaharoa rhyolitic eruption at Tarawera volcano, New Zealand is one well-established example of such an event (Figure 2). Figure 4 shows an example of a “mingled pumice” from the Kaharoa deposits and Figure 5 shows an apparent basalt-rhyolite mixing trend preserved in whole-rock geochemical variations from XRF analyses of Kaharoa glass, basalt inclusions, and pumice. Although these data, combined with additional petrographic indicators for mineral chemical disequilibria in erupted plagioclase and hornblende crystals (Leonard et al., 2002; Nairn et al., 2004) provide a compelling story, 1  A version of this chapter will be submitted for publication. Wilson, H.A. and Jellinek, A.M. 2010. A new method for diagnosing and distinguishing magma mixing and overpressure events using chemical variations in plagioclase.  13  Figure 4. Photograph of a mingled juvenile clast from the Hpdc deposit.  14  Figure 5. Plot of total alkali versus silica for Kaharoa eruptives.  15  the spatial and chemical extent, timing (relative to the eruption itself) and longevity of the proposed mixing event remain open questions and the motivation for this study. To more clearly identify and better understand the role of magma mixing in the Kaharoa eruption, I have developed and explored a methodology for distinguishing and characterising basalt-rhyolite mixing and related overpressure events as they are expressed in the growth history of plagioclase phenocrysts entrained within these erupted magmas. To do this, I have used the sensitivity of plagioclase growth, and albiteanorthite solid solution chemistry, to ambient pressure-temperature-water content conditions in the magma chamber. My goal is to broadly characterise a background “premixing” regime class of chamber dynamics such that I can distinguish and analyse departures from this state that may be related to “post-mixing” dynamics emerging as a result of a basalt injection. Schematically key elements of the problem before and after a basalt replenishment are shown in Figure 6. Assuming that pressure and water content are fixed, and that the chamber has a large aspect ratio, prior to basalt replenishment heat lost primarily to the roof can drive natural convection in the form of intermittent cold thermals (Jaupart and Tait, 1995). These thermals may be crystal-rich (Marsh, 1988; Bergantz and Ni, 1999), and descend into the underlying magma potentially driving, in turn, larger-scale overturning motions (Jellinek and Kerr, 1999; Ruprecht et al., 2008) (Figure 6). The magnitude of the temperature variations imparted at the cold thermal boundary layer (TBL) and carried into the underlying magma is governed by the nature of the temperature-dependence of the magma viscosity (Davaille and Jaupart, 1993; Manga et al., 2001) or its effective viscosity (Solomatov, 1995). The time scale for the  16  Figure 6. Diagram of a simplified convecting magma chamber.  17  descent of these cold drips, and the overturn time of the larger motions, govern the dynamics and define the basic time-averaged thermodynamic state of this idealised magma chamber. Plagioclase crystals growing within this system may respond to the time-dependent changes in the temperature field imparted by convective motions to acquire oscillatory zoning (e.g. Loomis, 1982; Pearce and Kolisnik, 1990; Singer et al., 1995; Ginibre et al., 2002; Perugini et al., 2006) according to corresponding variations in albite and anorthite activities (Figure 7a and 7b). Figure 7a shows solid solution curves for Ab-An and Ab-An-H2O melts crystallising under equilibrium conditions. Crystals growing in a pure plagioclase melt, under equilibrium conditions, will grow zones dependent on only temperature (e.g. Bowen, 1913; Loomis, 1982). Plagioclase crystals growing in a melt containing water will have an equilibrium crystallising composition that is very dependent on the water content at a a particular temperature (e.g. Yoder et al., 1957; Loomis, 1982). Crystals growing in complex, natural melts, will have equilibrium compositions that are dependent on the water content and the composition of the melt at the crystal-melt interface (e.g. Loomis, 1981, 1982). Equilibrium compositions are not particularly sensitive to small changes in pressure (0.5% An/1000 atm, Lindsey, 1968; Pringle et al., 1974), H2O content (1% An/1000 atm, Yoder et al., 1957; Johannes, 1978), or temperature (1% An/10º C, Kudo and Weill, 1970; Drake, 1976), however magmatic processes that are of interest, almost certainly do not reach equilibrium conditions. Nonequilibrium partitioning models (Loomis, 1981) predict that the crystalising composition will be more sodic than the equilibrium composition with the bulk melt composition. Both components of plagioclase feldspar, An and Ab, are depleted at the crystal interface in as the crystal is growing in complex melts, as the molar concentration of both  18  Figure 7. Graph of the plagioclase feldspar solid solution.  19  components is greater in the crystal than the melt. This is in contrast to plagioclase only melts, where Ab is concentrated at the interface (Loomis, 1982). Supercooling of the melt may result in variations of 2-3% An/10º C (Lofgren, 1974). The detailed spatial structure of the growth zoning that develops will depend on both the magnitude of temperature variations and on the time scale of these changes relative to the slow diffusive response time of the crystals (e.g. Ruprecht et al., 2008). A basalt replenishment can have a profound influence on the thermodynamic state of this system and on any preexisting plagioclase crystals growing within. Field observations of mafic-silicic layered intrusions indicate that mafic layers have high aspect ratios (Wiebe, 1993) and, thus, the rate of injection and spreading must be fast in comparison to their cooling time. Such an approximately impulsive thermal forcing at the base of the chamber can drive an additional mode of thermal convection in the form of hot rising plumes that will increase the mean temperature, change the temporal dynamics of the thermal stirring, and can lead to magma mingling and mixing (e.g., Snyder and Tait, 1995; Snyder and Tait, 1996; Snyder, 2000). In addition, the release of volatiles on solidification of the basalt can increase the water content (e.g. Sparks et al, 1977; Tait et al, 1989; Folch and Marti, 1998) as well as the pressure in the chamber (e.g., Blake, 1981; Tait et al., 1989). Such changes will cause, for example, albite (Ab) – rich zones to dissolve in favour of anorthite (An) –rich zones (e.g. Tsuchiyama, 1985), leading texturally to a resorbtion surface (Figure 7b) and subsequent quasi-periodic oscillatory zoning that is likely to be distinct in its character (Figure 7c). Although the signature of magma mixing events is widely reported in the deposits of explosive eruptions including Kaharoa, using plagioclase zoning to quantitatively  20  distinguish the pre- and post-mixing states in the magma chamber, in a statistically meaningful way, is not straightforward for three reasons: 1. How an eruption from discrete vents actually samples the underlying chamber in space and time is not known a priori and not easily constrained. 2. The extent to which the distribution of erupted plagioclase adequately records the full details of the thermo-chemical regime of the chamber as a whole is unclear. 3. Thermal variations at the scale of the thin thermal boundary layers (shown in Figure 4) requires An-Ab zoning to be resolved at very small length scales, corresponding to convective time scales, τc, ranging from hours to as long as a few years, depending mostly on the rheology of the convecting magma (e.g. Martin et al., 1989; Snyder and Tait, 1995; Jellinek and Kerr, 1999, 2001). Assuming that growth zoning is governed at leading order by Ca2+Al3+ ⇔ Na+Si4+ interdiffusion, the minimum zoning wavelength that must be resolved is "min # 2 $D% c , where D is the diffusivity, which depends primarily on temperature but also on water ! content and crystallographic direction (Grove et al., 1984; Cherniak, 1995), and τc is the  timescale for convection. The average temperature of the Kaharoa magma may have varied significantly, depending on the volume of new basalt. For a reasonable range in temperature of 850-1050 oC, D is plausibly on the order of 10-20-10-17 m2 s-1 (Baschek and Johannes, 1995; Cherniak, 1995), implying that λmin must be resolved to at least a few microns. To surmount some of the uncertainty in establishing a careful sampling of the Kaharoa magma chamber I restrict attention to the H-fall and Hpdc stratigraphic units of the eruption (Figure 3), which are the only units to contain unequivocal textural, mineral  21  chemical, and bulk chemical indicators of mixing (e.g. Figure 5, which shows continous compositions between rhyolite and basaltic endmembers) (e.g. Tefend et al., 2007). These units were sampled broadly in space to achieve, in principle, as good a picture as possible of the erupting Kaharoa magma chamber at the geologic moment during which the majority of the mixing occurred. From these samples, populations of plagioclase crystals sorted based on size, and textural properties, including the presence or absence of oscillatory zoning, and basic mineral chemistry were carefully extracted. Maps of chemical zoning at high spatial resolution were obtained using Nomarski differential interferometry (e.g. Nomarski and Weill, 1955; Anderson, 1983, 1984; Pearce et al., 1987; Pearce and Kolisnik, 1990; Stamatelopoulou-Seymour et al., 1990) and the results were compared with findings from backscattered electron imaging (Ginibre et al., 2002) and conventional microprobe analyses. The zoning maps were analysed using spectral analysis. Comparison of the results from this analysis was applied to characterise the Kaharoa magma at the H stratigraphic level, including the ‘basic state’ of the chamber that most crystals experienced, and the ‘departures’ from the average expressed in only a small percentage of the population. In addition, I will discuss important implications of making measurements following this method and how they can be applied to other magma chambers to determine critical time and length scales of the mixing process.  22  2.2.  Geology of the Kaharoa deposit and evidence for mixing The Tarawera Volcanic Complex (Tarawera henceforth) is located within the  Haroharo Caldera, in the Okataina Volcanic Centre (OVC), of the Taupo Volcanic Zone (TVZ) (Figure 2). The OVC has been the source of two major caldera forming eruptions (Matahina and Rotoiti) in the last 400 000 years (Nairn, 2002), and has average magma fluxes of approximately 0.003 km3/year over the past 65 ka (Wilson et al., 1995), making it among the most productive rhyolite centres in the world. Within the Haroharo caldera (probable collapse following the 65 ka Rotoiti eruption (Healy et al., 1964)), the locations of the Tarawera and Haroharo complexes appear to be controlled by fractures in the basement rocks, with eruptive vents lying upon two sub-parallel, NE-SW trending zones (Nairn, 1989; 2002). Five intracaldera eruptions have built the Tarawera complex: 22 ka Okareka, 17 ka Rerewhakaiitu, 13 ka Waiohau, AD 1315 Kaharoa, and AD 1886 Tarawera basalt (Nairn 1989; Leonard et al. 2002; Pers. Communication, Jim Cole, 2006). These eruptions have been dominantly rhyolitic in composition with increasing basaltic input, leading up to the most recent AD 1886 Tarawera basalt eruption that did not contain any rhyolitic melt (Pers. Communication, Jim Cole, 2006). I am interested in the voluminous AD 1315 Kaharoa eruption, the most recent of the rhyolitic events at Tarawera, because it is proposed to have been triggered by repeated basalt injections and magma mixing (Leonard et al., 2002; Nairn et al., 2004) and it had the largest (volumetric) proportion of basalt prior to the most recent basaltic eruption of Tarawera. The Kaharoa event was the largest (~4 km3) in NZ in the last 1000 years (Hogg et al., 1984; Nairn et al., 2001), and produced a sequence of rhyolite deposits  23  comprising phreatomagmatic deposits, pumice airfall deposits, lava domes, and pyroclastic flows (Nairn et al., 1992; Leonard et al., 2002; Nairn et al., 2004). Figure 2 shows the extent of the Kaharoa domes and pyroclastic flows. The distribution of the airfall is shown inset, however the many units shown in Figure 3 are not distinguished from one another on the map. The first airfall pumices, Units A through H (Figure 3), have a near uniform whole-rock composition with a few basaltic enclaves (Nairn et al., 2001, Leonard et al., 2002). The composition of the melt is rhyolitic, but enclave compositions span the entire range shown in Figure 5 (Leonard et al., 2002). Nairn et al. (2004) classify these rhyolites as their ‘T1’ composition magma, and suggest that these units have been affected by numerous basalt injections, referencing the multiple resorbtion surfaces and crystal zonation of plagioclase phenocrysts. Nairn et al. (2004) distinguish between their magma batchs, T1, T2, and T3, based on crystal content and compositional variations in the whole rock, glass, plagioclase and biotite geochemistry. The T1 magmas have slightly higher SiO2 and K2O contents than the T2 magmas, and lower CaO and Fe2O3. The T1 magmas also have significantly lower Zr and Sr, and much higher Rb contents than the T2 magmas. The H-fall unit is the last of the T1 magmas erupted, and is interbedded with the H pumiceous pyroclastic density current (Hpdc) deposit, which is, according to Nairn et al. (2004), a mixture of a ‘T1+T2’ magma and rare rhyodacite (derived from a T3 magma). Following the eruption of the Hpdc, units I through L have some ‘T1+T2’ signature, and then the remaining units were of the T2 type magma (Nairn et al., 2004). Results from Shane (1998) and Nairn et al. (2004) on a small number of samples, using spinel-oxide pairs (Ghiorso and Sack, 1991) and confirmed by amphibole-  24  plagioclase mineral thermometry (Holland and Blundy, 1994) give temperature estimates of 705-738 °C from a single H-fall lapillus, and 724±16 °C from an Hpdc ash sample. However, depending on the extent of basalt-rhyolite magma mixing the full range of temperature variations within the magma chamber may be much larger. The chamber depth is constrained in several ways. Melting experiments (Nicholls et al., 1992) on TVZ cummingtonite-bearing rhyolites (similar compositions to the T1 magmas) crystallise at pressures ≤3 kb (≤300 Mpa). Aluminum-in-hornblende (Johnson and Rutherford, 1989) mineral barometery and Blundy and Cashman (2001) Qz-Ab-Or-H2O projections, on a small number of crystals, give pressure estimates of 1.3±0.5 kb (130±50 Mpa) and 160200 Mpa, respectively (Nairn et al., 2004). Hornblende crystals in the deposits do not have reaction rims, which implies their ascent time from the magma chamber was relatively rapid, i.e., <4-5 days (Leonard et al., 2002). The H-fall is bi-lobate in map view, dispersed to the south-east and north-west (Figure 2a), whereas the Hpdc is only found in the south-east sector (Nairn et al., 2004). This distribution of the H-fall suggests that it was erupted from the Ruawahia and Crater vents, and the heterogeneity of the Hpdc clasts suggests that it was erupted from the Ruawahia, Crater, and possibly Wahanga vents (Nairn et al., 2004)(Figure 2). Despite being erupted from several vents, there is a remarkable homogeneity within both the T1 and T2 magmas, suggesting that the composition of the magma is independent of vent location (Nairn et al., 2004). The Hpdc unit may have some compositional variation between vents (Nairn et al., 2004), however this unit is generally the most heterogeneous. The H horizon (H-fall and Hpdc) is of greatest interest as it marks the transition between two relatively homogeneous rhyolite units, and has the most textural evidence of  25  magma mingling and mixing with injected basalts (e.g Figures 4 and 5). Contemporaneous chemical mixing is inferred from T1+T2 compositional findings (Nairn et al., 2004), and can also be seen in the variations in whole-rock data from Kaharoa glass, basalt inclusions, and pumice (Figure 4). Also of interest at this stratigraphic level are the hornblende-bearing and hornblende-free basalt inclusions. Leonard et al. (2002) argues that hornblende-bearing basalts are mixed more efficiently with the rhyolites, the basalts form ‘plume-like’, streaming extensions of brown glass into the rhyolite, and the two magmas often have crenulate margins. In contrast, they find that the hornblende-free basalts locally have crenulate margins with the rhyolite, but have an absence of the streaming extensions of glass. Leonard et al. (2004) suggest that the hornblende-bearing basalts were injected into the magma chamber at an earlier time, priming the chamber and the injection of the hornblende-free basalts happened just prior to eruption, acting as the final trigger to eruption.  2.3.  Methodology Populations of plagioclase crystals are sampled from the H-fall and Hpdc to  characterise both their “average” composition and departures from this average. Sample locations are shown in Figure 2. Bearing in mind the complications discussed in the introduction, I sampled the H-fall and Hpdc with two aims: (1) to characterise spatial variations in mineral chemistry at very high spatial (and thus temporal) resolution such that the distinct contributions of physical processes (e.g. those sketched in Figure 6) might be identified, and (2) to make comparisons between crystals during the eruption of  26  the H-fall and Hpdc. This methodology, outlined in Figure 8, is developed accordingly and discussed.  2.3.1. Sample preparation  2.3.1.1.  Crystal selection, mounting and orientation  With the aim of collecting a random sample, I sampled crystals from pyroclastic deposits as they are arbitrary samples of the Kaharoa magma chamber. One way to enforce a condition that these crystal populations plausibly represent a statistically meaningful “random” sampling of the Kaharoa magma chamber is to sort crystals by size and pick them according to well established crystal size distributions (CSD) (e.g., Sahagian and Proussevitch, 1998; Bindeman, 2003; Castro et al., 2003; Mock and Jerram, 2005). I make these comparisons to ensure that the size distribution of the crystals in my study are representative of the population of crystals within the deposits, not just the largest crystals present. Additionally, this method was developed to use with relatively small crystals compared to many crystals used in the literature, thus making it appropriate for application to a greater range of deposits. This comparison provides some indication of the extent to which I have sampled without bias towards the largest crystals, i.e. the histogram of my selected sample crystal population mimics the shape of the expected CSD curve (Figure 9). To compare the bulk field samples with CSD’s, both the H-fall and Hpdc samples were dried and sieved into five size fractions (>2 mm, 2-1 mm, 1-0.595 mm, 0.595-0.420 mm, and 0.420-0.350 mm) prior to hand-picking plagioclase crystals with biological forceps under a Nikon binocular microscope. The H-fall sample consists of 59 crystals,  27  Figure 8. Flowchart of the methodology developed and implemented in this thesis.  28  Figure 9. Graph of the size distribution of crystals from the H-fall and Hpdc samples  29  the Hpdc sample 47 crystals, and both samples have crystals from four size fractions (Figure 9). Crystals smaller than 0.350 mm in diameter were excluded from this study, primarily because of the practical difficulty with handling them. Individually picked crystals were carefully mounted in epoxy pucks such that the crystals were approximately perpendicular to either the [1 0 0] or [0 0 1] crystallographic axis. The crystals were oriented to investigate how zoning varies with crystallographic direction, because Ca2+Al3+ ⇔ Na+Si4+ inter-diffusion varies with crystallographic axis (e.g. Cherniak, 1995). This method was also adopted to maximize the number of ‘ideal cut sections’ (euhedral, centre-cut, with zoning perpendicular to the thin section) as described by Pearce (1984b), and to minimize profile distortion by stretching and truncation (e.g. Wallace and Bergantz, 2004). Next, the pucks were ground until all crystals were intersected, and continued until the crystals were approximately bisected lengthwise (so as to obtain near-complete core to rim cross sections). The pucks were polished to a final 0.05 µm finish (Appendix E).  2.3.2. Methods for characterisation of zoning:  2.3.2.1.  Backscattered Electron (BSE) imaging  A Philips XL-30 scanning electron microscope with a Bruker Quantax 200 Microanalysis System and an XFLASH 4010 detector was used to acquire highresolution backscattered electron images. The BSE image contrast is digitally enhanced in Adobe Photoshop™ by shortening the limits of the image histogram (frequency of 30  pixels at each greyscale value), thereby increasing the bandwidth over which information within the image is displayed. Practically, this is accomplished by taking the histogram and adjusting the black and white points to spread the grey values over a larger range of the 256 possible greys in the spectrum. These images are then used to classify the crystals into preliminary textural groupings, which I will discuss in section 2.4.1. This method was chosen in favour of the image stacking technique of Ginibre et al. (2002) because it requires less instrument time and both methods lead to quantitatively similar results.  2.3.2.2.  Electron Microprobe Analyses (EMPA)  Two subsets of crystals from each sample were chosen, H-fall and Hpdc, for Electron Microprobe Analyses (EMPA) to span the compositional and textural variation found in the BSE images. The first subset was chosen for crystal traverses with 5 µm spot spacing, and the second for select spot analyses, both using a 5 µm beam size. The traverses were placed parallel to crystal faces, intersecting the core region, and where possible, avoiding cracks within the crystal. Spot locations were chosen to capture the maximum anorthite variation within the crystal and can be used to normalise BSE images, or NDIC interferometry profiles. All samples were analysed with a Cameca SX50 Scanning Electron Microprobe with four vertical wavelength-dispersion X-ray spectrometers and a SAMx energy-dispersion X-ray spectrometer. A beam current of 10.02 A with accelerating voltage of 15.03 V was used.  31  2.3.2.3.  Nomarski Differential Interference Contrast (NDIC)  imaging To obtain the highest possible spatial resolution I used NDIC imaging (e.g. Nomarski and Weill, 1954, 1955; Anderson, 1983; Pearce et al., 1987; Pearce and Kolisnik, 1990; Stamatelopoulou-Seymour et al., 1990), a technique that is useful for identifying chemical zoning and resorbtion surfaces in minerals with solid solutions such as plagioclase, olivine, and augite (e.g. Anderson, 1983, 1984; Clark et al., 1986; Pearce and Kolisnik, 1990). To do this, each sample puck is etched for 30 seconds with 50 wt.% fluoroboric acid (HBF4), which dissolves calcium faster relative to sodium. This process creates a microtopography, the wavelength of which is related to the spatial scale of AnAb chemical zoning (e.g. Pearce and Kolisnik, 1990). The etched crystals were viewed using NDIC lenses on a Nikon Optiphot polarizing microscope with reflected light. The crystals were imaged using a QIMAGING RETIGA Exi digital video camera.  2.3.3. Spectral analyses Spectral analysis was used to characterise quantitatively the spatial scales of periodic chemical variation (EMPA, BSE) or micro-topography (NDIC) in the images. Greyscale profiles (Appendix J) were measured on the image parallel to cleavage, or twinning direction (starting and ending on the same zone) (more detail in Appendix I). Profiles were aligned so that all profiles start at the same relative position to a particular zone, and were then averaged to maximize the signal-to-noise ratio. To enhance spectral  32  resolution of the shortest wavelengths (i.e., the shortest timescales) the profiles are in turn, demeaned, detrended, and differenced. To estimate spectra in the most accurate possible way, I compare results from a fast Fourier transform (FFT) applied to the whole Hann tapered profile, from the average of overlapping segments of the profile (Welch, 1967) and from an adaptive Multi Taper Method (MTM) (Thomson, 1982).  2.4.  Results  2.4.1. Textural and chemical characterisation The crystal populations were chosen from both the H-fall and Hpdc such that the resulting sample population closely matches the crystal size population within the deposits (i.e. if there are many crystals at a particular size fraction, I included more of those crystals in my sample population). I found that plagioclase crystals were most abundant in the <0.595 mm size classes for both the H-fall and Hpdc. However, of note, most of these crystals are fragments, which appear to have broken along cleavage and/or twin planes during eruption. The crystals are typically partially surrounded by thin, vesiculated, glass “jackets”. Figure 9 shows the relative frequencies of crystals sampled from the H-fall and Hpdc. For reference, the dark dashed line in Figure 9 is a typical crystal size distribution (CSD) of a magmatic growth signature as reported by workers (e.g., Sahagian and Proussevitch, 1998; Bindeman, 2003; Castro et al., 2003; Mock and Jerram, 2005). The fragment size distribution (FSD) expected from an explosive volcanic eruption (Bindeman, 2005) has a similar form. The population is consistent  33  with those measurements and thus, I took it to be a reasonable sample of the various sizes of crystals within the two deposits. Next, textural groupings of the crystals were made using the BSE images, and further refined these groupings with the EMPA data. The relative textural frequencies are plotted in Figure 10. The distinctions between the ‘large variation’ and ‘small variation’ groups can be found in Table 1. Some textures are similar to those described in Leonard et al. (2002). However, based on their work I did not sample the plagioclase from their high-Ca basalt (cores as high as An98.9), as my measured anorthite contents only range from An16 – An64. The ‘patchy’, ‘patchy cores’, ‘alternating’, ‘calcic cores’, and ‘sodic rims’ textural groups are characterised by relatively high variations in anorthite content (i.e., > 10 mol %), and are hereafter referred to as the ‘large variation’ crystals. The ‘moderate’, ‘low’, and ‘subtle’ textural groups have smaller variations in anorthite content (< 10 mol %), and are subsequently referred to as ‘small variation’ crystals. All groups have some crystals with resorbed and/or embayed rims and/or zone boundaries, apparently controlled by cleavage and/or twin planes. There are no examples of ‘patchy’ and ‘patchy cores’ crystals in the Hpdc sample, and ‘sodic rims’ in the H-fall sample. Examples of three ‘large variation’ texture crystals are shown in Figure 11 and a comparison of the various techniques that were employed to visualize zoning. Column (1) is an example of a ‘patchy cores’ texture crystal. This crystal has easily identified cleavage in one direction (the profile was placed parallel to this direction), and has polysynthetic twinning in a nearly orthogonal direction. The overall trend found in the BSE intensity data (1d) corresponds generally to the changes in the absolute anorthite  34  Figure 10. Graph of the relative frequencies of the various textural/compositional groupings for each of H-fall and Hpdc samples.  35  Table 1. Textural/compositional groupings of plagioclase crystals. TEXTURE/COMPOSITION  GROUP  DESCRIPTION  Patchy*  large variation (>10% ΔAn)  Crystal is dominated by patchy texture, glass inclusions are common  Patchy cores*  large variation  Core region displays patchy texture, glass inclusions are common in the core  Alternating  large variation  Crystals have alternating high and low An zones – similar to oscillatory zoning but most changes happen across pronounced resorbtion surfaces  Calcic cores  large variation  Cores are small, often euhedral or subhedral, and relatively much more calcic than the rest of the crystal  Sodic rims  large variation  Crystals have large core regions with more sodic, euhedral rims  Moderate contrast  small variation (<10% ΔAn)  Some zoning visible in original BSE images – larger variations between zones than ‘Low’ texture crystals  Low contrast  small variation  Some zoning visible in ‘Enhanced’ BSE images  Subtle contrast  small variation  No zoning visible in BSE images, usually <5% ΔAn  *‘Patchy’ and ‘patchy cores’ likely correspond to sieve textures described by Leonard et al., (2002). They also describe clear rims (<0.1 mm) on all plagioclase in the fall pumices and notes corroded/embayed rims and/or zone boundaries, normal, reverse, and oscillatory zoning, and the presence of glass inclusions in other crystals.  36  Figure 11. Crystals with 'Large variation' in anorthite content.  37  38  39  content across the crystal (1b) (ranges from An27 – An45). However, the BSE data (1d) is noisy, with large pixel-scale variations in greyscale values, and consequently, the small variations in anorthite are undetectable in a statistically meaningful way. In contrast, the NDIC image (1e) and corresponding greyscale traverse (1f) shows greater detail at small scales. The crystal in column (2) is an example of an ‘alternating’ texture crystal, and has readily identified cleavage parallel to the analysis profile and fine polysynthetic twins in the near orthogonal direction. This crystal has more contrast in absolute anorthite content over the crystal (ranges from An20 – An50) than the crystal in column (1), and thus, the correspondence with the BSE greyscale traverse (2d) is more apparent. The BSE greyscale data (2d) is, however, still much noisier than the NDIC greyscale data (2f). Finally, column (3) is an example of a ‘sodic rims’ texture crystal. This crystal has cleavage that is difficult to identify, with polysynthetic twins that are at an angle to the crystal faces (and zoning) (3e). For this crystal, I chose to measure greyscale profiles parallel to the twinning as it is the only known reference plane, and is likely to be parallel to one of the crystallographic axes. Again, I see that the BSE greyscale data (3d) is noisier than the NDIC greyscale data (3f), and more detail is visible in the NDIC image (3e). The EMPA spot analysis from the core region is An41, and from the rim, An21. Examples of the ‘small variation’ textural grouping are shown in Figure 12. The crystal in column (1) has anorthite content ranging from An18 – An26. This crystal has easily identifiable cleavage in one direction, and has polysynthetic twinning in a nearly orthogonal direction (the profile was placed parallel to this direction). The overall trend found in the BSE intensity data (1d) corresponds generally to the changes in the absolute  40  Figure 12. Crystals with 'Small variation' in anorthite content.  41  42  43  anorthite content across the crystal (1b). However, the BSE data (1d) is again noisy and the small variations in anorthite are undetectable in a statistically significant way. In contrast, the NDIC image (1e) and corresponding greyscale traverse (1f) show more detail at small scales. The crystal in column (2) has anorthite content ranging from An19 – An29, and has cleavage perpendicular to the analysis profile and fine cleavage planes in the near parallel direction. The NDIC image (2e) reveals fine zoning faces that are at angles to both of the visible cleavage directions. This crystal has similar contrast in absolute anorthite content across the crystal to that of the crystal in column (1), and similarly, the correspondence between the EMPA (2b) and BSE greyscale traverses (2d) are not meaningful. The BSE greyscale data (2d) is still much noisier than the NDIC greyscale data (2f). Finally, the crystal in column (3) has anorthite content ranging from An20 – An27. This crystal has cleavage in one direction, with polysynthetic twins in two directions (3e). For this crystal, I chose to measure two greyscale profiles parallel to the twinning (nearly perpendicular to the zoning) (one in each direction). Again, the BSE data (3d) is noisy and, in this case, inconsistent with the trend of the EMPA data. Comparatively more meaningful variation at small wavelength detail is visible in the NDIC image (3e). All of these crystals show little zoning in the BSE (Figure 12, row a) or enhanced BSE (Figure 12, row c) images, however, the NDIC images (Row e) reveal fine scale zoning, twinning (e.g. columns 1 and 3), and otherwise undetectable crystal faces (e.g. column 2).  44  2.4.2. Spectral analysis  2.4.2.1.  Comparison of spectral methods  A comparison of results from four spectral estimation algorithms of an NDIC greyscale profile are shown in Figure 13. Figure 13a shows a power spectrum of data that has been first detrended by removing a polynomial. Detrending removes monotonic variations over the length of the dataset, which include ‘shadow’ effects produced by uneven lighting with NDIC imaging. The mean is then removed and a Hann window is used before computing the fast Fourier transform. Examination of Figure 13a shows that this method does not capture structure in the data very well below ~10 µm.  In contrast,  Figure 13b shows a spectrum of the same data, detrended through a differencing operation. Detrending by differencing is a filtering operation that removes power at long wavelengths and enhances power at short wavelengths through spectral multiplication, making it more effective for resolving short wavelength phenomena than simple detrending. Again, the mean is removed and a Hann window used. This method works well to the eye for this dataset, with structure recovered at both short and long wavelengths. To improve spectral resolution I employ the Welch method and Thompson Multi-Taper Method (MTM) (Thomson, 1982). The Welch method involves splitting the dataset into a number of overlapping segments, that are each windowed using Hann windows, computing the Fourier transform, and finally the modified periodograms are averaged together to produce an estimate for the whole profile. The MTM also estimates the power spectra from a combination of modified periodograms. However, in this case the periodograms are calculated using a sequence of orthogonal tapers (windows in the frequency domain) that are optimized for high or low frequency content. Figure 13c 45  Figure 13. Plots of normalised power spectra showing different spectral methods.  46  shows a spectrum of the data detrended by differencing, mean removed, and windowed using the Welch method. Finally, Figure 13d is the spectrum obtained by differencing, mean removed, and using the MTM. Figure 13e is a comparison of the four spectral estimation methods. Inset in Figure 13e is an illustration showing how peak locations were determined. The heavy-black horizontal lines show where I have chosen as the “bases” of the peaks. A base is chosen for each major peak, usually at a prominent change in slope. Then, the full-width half maximum method is used to determine the peak location, marked by the vertical arrows. The error for each peak is represented by the crossbar on each arrow, and is approximately 2σ. Several of the techniques have high power at common periods, however, the Welch and MTM methods have better resolution at shorter wavelengths. This is observed most clearly at wavelengths < 4 µm where peaks of the Welch and MTM methods have overlapping peaks. Consequently, I use the Welch method for most of my calculations because the frequency/period resolution is sufficient and it is easier to implement.  2.4.2.2.  Comparison of EMPA, BSE, and NDIC profiles  Spectra obtained from different analytical techniques are compared in Figure 14. Figure 14a shows the power spectra computed for a typical ‘small variation’ plagioclase crystal (Fig. 14c) with single EMPA, Nomarski DIC greyscale, and BSE greyscale traverses in solid black, dotted, and dashed lines, respectively. Also shown is a 47  Figure 14. Plots of spectra computed from various analytical techniques performed on a single crystal.  48  characteristic timescale assuming that " c # $2 4 %D , where λ is a characteristic wavelength and D is the diffusivity calculated for a temperature of 880°C (Leonard et al.,  ! 2002; Barclay et al., 1998), under anhydrous, 0.101 MPa conditions, using diffusivities calculated for lead diffusion in oligoclase (An23) perpendicular to the c-axis, (001) as determined by Cherniak (1995). In sodic plagioclase, decreases in Na are correlated with increases in Pb and Al (Cherniak, 1995), and therefore appropriate for representing NaSiCaAl exchange in this system. In the EMPA spectrum, power is concentrated in a sinusoid with an 11.4 ± 1.1 µm wavelength, implying a period for thermal variation of 1.2-1.8 years. In addition, relatively less power is distributed over three longer wavelengths, recording magma chamber dynamics on decadal timescales. In the NDIC spectrum power is distributed over 4.4 ± 2.4 and 11.3± 4.0 µm, similar to the EMPA data, with an additional 4.4 µm wavelength, corresponding to approximately 2.7 months. The spectrum from the BSE data is comparatively less resolved with a single broad peak centered at 7.2 ± 4.4 µm. Figure 14b shows power spectra computed from the average of five greyscale traverses shown in Figure 14c from the NDIC image, and five from the BSE image (the single traverse EMPA spectra is shown again for comparison). Averaging increases the signal to noise ratio. Care is taken to align the profile start and end points, as well as keep profiles parallel to twin planes, cleavage surfaces, or crystal faces (as available). Consequently, the NDIC now has significant power at three well-resolved wavelengths 4.2 ± 0.5, 5.3 ± 0.6, and 12.4 ± 3.9 µm, and one is in the same location as the high power EMPA peak. The averaged BSE data is characterised by two well-resolved, significant power peaks at 3.5 ± 0.4 and 5.7 ± 1.0 µm, with three lower power peaks.  49  As an additional comment related to averaging, I restrict profiles to within regions of similar character. The spectrum from the EMPA traverse (Fig. 12, 1b) across the crystal has the lowest spatial resolution, because the distance between evenly spaced spots is large (5 µm). Ginibre et al. (2002) found that 0.5 µm spatial resolution is possible with BSE imaging. NDIC imaging can, in theory, be used to obtain much higher spatial resolution as the acid-etch effects the crystal surface on the atomic scale. However, in practice it is difficult to obtain a polished surface without imperfections. In addition, sufficient light for high quality images becomes difficult at higher magnification. Consequently, the maximum spatial resolution is approximately 0.3 µm, corresponding to a timescale of 9 hours. Finally, in Figure 14c the greyscale traverses cross a natural crack in the image, which has a distinctive signature in each profile: because each profile crosses the crack in a different place, and artificial periodic component at 4.2 µm is added to the averaged NDIC data. The NDIC spectrum for this dataset is otherwise very similar to the original plot, with slightly more power at the smallest wavelengths. However, when the crack is removed from the BSE data, the character of the entire periodogram changes, with moderate power at short wavelengths (< 2 µm) and high power at the length of the dataset. This suggests that the main structure in the BSE data was that of the crack, not the crystal zoning.  50  2.5.  Discussion  2.5.1. Oscillatory zoning: the basic state of the H and Hpdc magma and uncertainties Small periodic changes in anorthite content (1-3 mol % An), or oscillatory zoning, exists in a large number of the crystals examined here (42 of 60 H-fall crystals, and 36 of 47 Hpdc crystals) (e.g. Figure 10). These variations are often accompanied by fine dissolution/resorbtion surfaces followed by continued, near parallel growth zoning. I propose that these crystals represent the ‘average’ plagioclase crystals growing within the Kaharoa magma chamber, and they might be used to define the ‘basic state’ of the chamber. Oscillatory zoning has been hypothesized by some to represent the feedback between the crystal growth rate and the local diffusion rate (Bottinga et al., 1966; Allègre et al., 1981; Pearce and Kolisnik, 1990; Pearce, 1994; L’Heureux and Fowler, 1996; Fowler et al., 2002). Others have attributed the small repetitive changes in anorthite content (i.e. 1-3 mol % An) (Pearce and Kolisnik, 1990) to arise as a result of periodic variations in temperature carried by convective motions acting at distinct spatial scales (e.g. Figure 6) (e.g. Loomis, 1982; Anderson, 1984, Pearce and Kolisnik, 1990; Singer et al., 1995). In general, the equilibrium plagioclase solid solution is relatively insensitive to small changes in pressure (0.5% An/1000 atm, Lindsey, 1968; Pringle et al., 1974), H2O content (1% An/1000 atm, Yoder et al., 1957; Johannes, 1978), or temperature (1% An/10º C, Kudo and Weill, 1970; Drake, 1976), as stated earlier. As a result, large changes in these parameters at equilibrium conditions would be necessary to result in the fine, repetitive zoning observed. Supercooling results in more significant variations of 251  3% An/10 ºC (Kudo and Weill, 1970; Drake, 1976), which is of the order needed to describe the variations in anorthite content noted here. To explain these periodic zoning patterns in terms of pressure changes, a periodic process, such as tidal pulses of magma upwards (e.g. Anderson, 1984) would need to be invoked. As both the H-fall and Hpdc were pyroclastically erupted, without significant hornblende reaction rims (Nairn et al., 2004), it is unlikely that the Kaharoa magma was moving slow enough as to be controlled by tidal motions. These variations in An could be explained by changes in H2O content that the growing crystals were in contact with. However, it is difficult to imagine a process that might periodically increase or decrease the melt in water. The preferred hypothesis for the developement of oscillatory zoning is that of periodic and dynamic movement of crystals and melt through temperature variations within the Kaharoa magma chamber. Oscillatory zoning in crystals from the ‘small variation’/‘basic state’ H-fall and Hpdc can be described by peaks found in spectra obtained by analysing NDIC and BSE greyscale images. Figure 15a shows spectra calculated from NDIC and BSE images of a representative ‘small variation’ crystal, in black and red, respectively. The spectrum calculated from the BSE image is noisy at short wavelengths, and has significant power at the length of the dataset. This is typical of analyses of the ‘small variation’ crystals using the BSE images, as I was unable to further enhance image contrast, and the resulting spectrum is predominantly noise. Peak locations for a few ‘small variation’ crystal spectra are shown in Fiure 15b, from two size categories, for both the H-fall and Hpdc, denoted by the open and filled circles, respectively. Error bars show 2σ variations for each peak where 2σ is twice the  52  Figure 15. Plots of spectra from 'Small variation' crystals.  53  width of the peak at half maximum (i.e. the 95% confidence limit). From detailed analyses of six crystals, zoning in the ‘basic state’ is characterised by a 3.1–12.4 µm bandwidth, comparable to other crystals within these deposits. This wavelength band corresponds to timescales in the range 39 days to 1.8 years. That each crystal has multiple wavelengths suggests that the magma chamber convection involved motions at many scales. Spectra from this ‘small variation’ group commonly have similar character peaks, although not in the same position. Assuming similar growth conditions, slight shifts in the position of the peaks could be due to slight misalignment of the crystals in the epoxy, and result in profile distortion as discussed by Wallace and Bergantz (2004). The shift in peaks associated with a 10° and 20° misalignment of a given crystal in the epoxy was calculated, and I find that misalignment most strongly affects peaks at the longest wavelengths. For a 10° misalignment, the longest peaks shift 0.16 µm (3 hours), whereas the shortest peaks shift less than 0.06 µm (corresponding to less than 22 minutes). A 20° misalignment can result in a shift of < 0.18 – 0.49 µm (3.3 – 24 hours) for the shortest to longest wavelengths, respectively. Even considering a misalignment of 20°, peaks do not shift past the estimated uncertainty of the peak location itself. Misalignments of greater than 20° are unlikely, as past this degree of wobble in the epoxy I expect the crystal to have been aligned with respect to a different crystallographic axis, i.e., perpendicular to the a-axis, (100), instead of perpendicular to the c-axis, (001). Alternatively, shifting in peak positions may be due to variable growth conditions within the magma chamber. Diffusivities are dependent upon temperature, and can vary over orders of magnitude with changes in dissolved H2O (Watson, 1994). For example,  54  if diffusivities are calculated for a reasonable temperature range, 850-1050 °C, I find that diffusion across 10 µm can take 12.8 days to 2.4 years. As a result, I expect the timescales calculated represent the slowest scenario, as this melt is very water rich and diffusivities are likely another order of magnitude larger. Finally, some misalignment of spectra peaks may be due to the crystallographic orientation of the samples and I consider these implications in the next section.  2.5.2. Variations in wavelengths with crystallographic direction – a natural diffusion experiment I tested the hypothesis that variation in zoning thickness is due to the difference in diffusivities along crystallographic axes, as predicted by Cherniak (1995). If the c-axis (001) is in the plane of the crystal section, the diffusivities, DA and DB, in the short and long directions respectively, will vary by one order of magnitude perpendicular, and parallel to the (001) crystallographic axis for an oligoclase (An23) composition. Thus I expect, 1  "A # DA & 2 ~% ( , "B $ DB ' where δA and δB are wavelengths measured in the short and long directions, respectively. ! plagioclase crystal with continuous zoning in a short, δ , Figure 16a shows a schematic A  and long direction, δB. Crystals with uneven cross-sections (apparent short and long directions) and continuous zoning were chosen. Measurements were made parallel to cleavage and/or twinning in the two crystals shown (Figure 16b), starting and ending on a 55  Figure 16. Plots of spectra computed from zoning in two directions.  56  continuous zone. Inset in each the three plots of Figure 16b are images of the crystals from which the spectra were computed, with dashed lines to highlight zoning, and red and black lines to show where the greyscale traverses were measured. Differences in diffusivity along the three crystallographic axes are expected to manifest as slightly shifted peaks in the computed spectra. In the top plot, I see that the highest power peak in both directions has nearly the same wavelength, and the peaks are statistically indistinguishable. At shorter wavelengths, the peaks are also aligned. In the lower plot, there are three peaks with significant power in both directions, but the two spectra have similar overall characteristics. The ratios of δA to δB are plotted in Figure 17 for pairs of peaks from Figure 16b. A ratio of 1 corresponds to the condition that the a- and b-axes are in the plane of the section. A ratio of 1/10 corresponds to an upper bound (Cherniak, 1995) where the c-axis is in the plane of the section. I find δA≈δB for each of the three common wavelengths in the top plot of Figure 16b. This result indicates an isotropic diffusivity and implies that I 1  am looking at the a-b plane. In contrast, "A # ( 7 20) 2 "B for each of the three common wavelengths in Figure 16b, bottom. This is consistent with expectations from experiments (Cherniak, 1995). !This analysis shows that the NDIC-based technique can potentially be applied to rigorously interrogate the dependence of chemical diffusivities on crystallographic directions in plagioclase and other minerals.  57  Figure 17. Graph of δ A/δ B for peaks in Figure 16.  58  2.5.3. Oscillatory zoning and resorbtion: Potential departures from the basic state A major effect of the injection and spreading of hot basaltic magma layers is to perturb the thermal state and enhance the convective vigour within a silicic magma chamber (Figure 6). In addition, the release of volatiles on cooling and solidification of the basalt can influence the pressure and water content in the chamber. Indeed, as is discussed in section 2.1, this is a common view of how basalt injections might trigger an eruption (e.g. Tait et al., 1989; Pallister et al., 1992). For very large injections, one expected consequence of the resulting transient thermal and chemical disequilibrium in the chamber is that plagioclase crystals may dissolve (or grow) at an accelerated rate leading to resorbtion surfaces. To characterise the nature of the change in the thermal and dynamical regime of the magma chamber, as a result of a basalt injection, it is of interest to examine the chemical zoning on either side of such a surface. I find very few examples of major resorbtion surfaces across which the anorthite composition varies by more than 3 mol %. However, the crystal shown in Figure 18 (crystal also shown in column 3 of Figure 11) is one case. The resorbtion surface is marked with a dashed black line. Parallel and quasi-periodic zoning is on either side, in both the core and rim regions. In the core region, the zoning appears coarser (higher amplitude changes, right panel, Figure 11f) than in the rim region, and has an overall higher anorthite content (e.g., right panel of Figure 11c, and EMPA points of An41 and An26 in the core and rim, respectively). Also shown in Figure 18c are white and red arrows that are parallel to the greyscale traverses that were measured. Greyscale profiles taken parallel to the twinning (white arrows) found in the crystal were analysed, rather  59  Figure 18. Photograph and plots of spectra from a NDIC image of a plagioclase crystal with parallel and periodic zoning on either side of a major resorbtion surface.  60  than perpendicular to the crystal faces, so that possible changes in the rates of processes relative to one of the crystallographic axes can be evaluated. For example, assuming the twinning follows the albite twin law (composition plane (010) (e.g., Deer et al., 1966)), I conclude that I am looking down either the c or a crystallographic axis. However, greyscale traverses perpendicular to the zoning are included, denoted by the red arrows, for completeness. Figure 18a shows spectra determined from the core region of this crystal. Comparison of results indicates that both traverses, parallel to twinning and perpendicular to zoning, have power at three scale lengths. The difference in peak locations can be accounted for by the difference in profile lengths, i.e. if I consider the angle at which the two profiles intersect, calculate the resulting profile stretching, normalise both profiles to the same length and calculate the spectra, I find that they have peaks at the same wavelengths. Comparison of the profiles taken from the rim (Figure 18b) shows similar shifting of peaks between the ‘parallel to twinning’ and ‘perpendicular to zoning’ profiles. Of particular interest is the difference in character of the periodic zoning between the core and rim regions. Whereas power is distributed among three wavelengths between 3.5 and 17.9 µm in the core, in the rim power is concentrated in two harmonics restricted to the narrower and shorter wavelength band of 3.5-8 µm. This result is statistically robust and provides the opportunity to test hypotheses with a more extensive data set. For example, within the framework of magma chamber convection illustrated in Figure 6, the reduction in the number of harmonics and the factor of 2 decrease in the maximum wavelength implies that the structure of the flow changed and that the stirring became more vigorous. However, other and varied hypotheses are certainly permitted by  61  these results. The similarity between the spectral results for the rim and the combined results in Figure 15b, for example, supports a possibility that this plagioclase crystal entered the magma chamber with a hot basalt and then began crystallising a more sodic composition once in the magma chamber. Identifying the correct geological interpretation for Figure 18 is not the goal of this discussion rather, the analysis permits interrogating such speculations in a such a way.  2.5.4. Comparison with published work The method presented here for characterising chemical zoning in plagioclase in volcanic systems has significant advantages over previous work. First, a statistically random sample of crystals was collected from one stratigraphic level. If plagioclase crystals act as Lagranian tracers of magmatic conditions, then in principle a random sampling of these conditions at a given time by sampling from eruption products that have been fragmented (i.e. no one crystal has an associated ‘neighbour’ crystal) can be achieved. This is in contrast to sampling techniques used by others (e.g. Wallace and Bergantz, 2002) for ‘Lagrangian trajectory analysis’ and subsequent attempts to determine a ‘mixing phylogeny’ (Wallace and Bergantz, 2002, 2004, 2005). Wallace and Bergantz (2002, 2004, 2005) restrict samples to mechanically connected rocks, i.e. lavas, to assess particle paths of crystals, modes of transport and dispersal mechanisms. I do not restrict sampling to lavas because I want a random sample of the magma chamber. However, eruption and/or convective motions  62  gather crystals over length scales of tens of meters (Ruprecht et al., 2008), so near random samples may be achieved by sampling even in lavas. Second, crystals were oriented for analyses. This gives more ‘ideal cut sections’ (Pearce, 1984b; Wallace and Bergantz, 2002, 2004) that are oriented at 90° to the thin section surface and penetrate the core region of the crystal, which results in a larger sample set. Wallace and Bergantz (2004) find that the number of profiles (one per crystal) needed to resolve populations of crystals is more dependent on the normalisation routine than the correlation technique, i.e. defining populations of crystals is most dependent on determination of ‘ideal cut sections’. Most of this problem of ‘normalisation’ has been removed by simply orienting the crystals prior to analyses. In addition, it is possible to determine which crystallographic axes are in the analysis section by comparing wavelengths in two directions (e.g. Figures 16 and 17). This allows for comparison between crystals relative to the same crystallographic axis. This method has similar or better resolution compared to other studies (e.g. Ginibre et al., 2002). I find two or three characteristic wavelengths in each crystal within the 3.1–12.4 µm bandwidth as discussed in section 2.5.1. In addition, I show that wavelengths found in single crystals may not be characteristic of the population, and it is indeed necessary to examine a large number of crystals from each deposit to be able to make interpretive statements about pre-eruptive conditions. Because of the high resolution that I am able to achieve, this method can be applied to crystals over a range of size fractions, including small crystals that are typically disregarded. This allows for the potential application to a variety of volcanic samples that have not been extensively studied because of small-sized phenocryst  63  populations. Crystals over a range of size fractions were also examined for each deposit. This approach is advocated as it could yield information regarding changes in growth history and/or changes in convective motions that are at the scale of the crystals. Finally, less bias is imparted with respect to large changes in mol % An using NDIC images than with only BSE images because I am able to achieve better dynamic range (i.e. I can detect more subtle greyscale variations). This type of zoning, Type II (3100 µm, up to tens of mol % An) (Pearce and Kolisnik, 1990), is identified using BSE images in conjunction with EMPA spot analyses and traverses. Each textural group is considered separately, and qualitatively determined if the Type II zoning is periodic (and appropriate for Fourier analysis). Of the ‘large variation’ textures, only the ‘alternating’ group may be considered fully quasi-periodic, and appropriate for direct input into the Fourier routine. Other non-periodic textural groups can be analysed in piecewise segments, e.g. Figure 18. This approach is used here in favour of wavelet-based techniques (Wallace and Bergantz, 2002, 2004) because it retains all spectral information at short wavelengths as well as data with small amplitudes without needing to filter for a specified bandwidth (Ginibre et al., 2002; Wallace and Bergantz, 2002, 2004). In this way, I am able to treat quasi-periodic zoning of both Type I (or ‘oscillatory’) (Pearce and Kolisnik, 1990), and Type II zoning without bias towards large magnitude changes at long wavelengths.  64  2.5.5. Summary: Applications to Kaharoa and other eruptions Whereas it is clear that basalt injections played a role in the Kaharoa eruption (mingled pumices, basaltic enclaves), in contrast to previous work (Leonard et al., 2002; Nairn et al., 2004), my results do not support the picture of an eruption triggered by a single, large-scale basalt-rhyolite magma mixing event. I find that the majority of plagioclase crystals within the H-fall and Hpdc deposits record periodic zoning on 3.1– 12.4 µm length scales. If these variations are related to temperature variations within the Kaharoa magma chamber, then convection preceding this eruption was characterised by motions acting over timescales of 39 days to 1.8 years. These anorthite variations in my ‘basic state’ crystals are small, i.e. less than 10 mol % An changes across the crystals. Thus, convection within the chamber probably carries only small temperature variations, not to scale with the variations accompanying a large basaltic intrusion. Other possible contributions to the zoning in these crystals include changes in water content, over/under pressure events, and interaction with basaltic magma. However, the key observation is that of periodic zoning in the majority of the crystal populations (H-fall and Hpdc). As such, I expect the processes that they were experiencing while growing to also be periodic. Convective overturning (e.g. Singer et al., 1995) is a periodic process, and the dewatering of basalt (causing local H2O content differences) could be considered periodic if the water-rich magma was carried by convective currents. In contrast, over/under pressure events are not obviously periodic in the magma chamber and basalt injections are generally considered stochastic processes. In this case, pressure changes may have had some impact on crystal growth within the Hstratigraphic horizon, as the Kaharoa chamber may have experienced near periodic  65  depressurisation events accompanying the eruption of the A through G tephras, prior to erupting the H-fall and Hpdc. However, if this mechanism could only be used to account for a single wavelength of zoning, related to these eruptive pulses. All of the crystals analysed had more than one wavelength of zoning. Random, non-periodic events would contribute to the noise found in the spectra. However, I find that the spectra, associated with the ‘basic state’ crystal population, have very little noise. Additionally, few examples of plagioclase crystals with major resorbtion surfaces were preserved and few crystals with Type II zoning were found. The zoning on either side of major resorbtion surfaces is commonly periodic as well, suggesting that even the crystals that may have experienced a stochastic event still had growth that was dominated by ongoing periodic processes. The Okataina Volcanic Centre has had a long history of activity (last collapse at ~65 ka Rotoiti eruption (Healy et al., 1964)), and five intracaldera eruptions from 22ka have built the Tarawera complex (Nairn 1989; Leonard et al. 2002; Pers. Communication, Jim Cole, 2006). The most recent eruptions, Kaharoa and the AD 1886 basaltic eruption, had vents that were structurally controlled (Nairn et al., 2004). The AD 1886 basalt eruption formed an 8 km long fissure that dissected the Kaharoa domes. This fissure could be used to estimate a lower bound on the areal extent of the Kaharoa chamber, with 4 km as a radius, area = "r 2 area = 50.3 km 2  .  An upper bound for the areal extent is given by the caldera diameter of ~20 km giving, !  area = 314.2 km 2 .  If I consider that the minimum Kaharoa magma chamber had a volume equal to that  ! 66  erupted (4 km3), then I estimate chamber thicknesses ranging from 12.7 m to 79.6 m. Strong heat flow in the OVC, 600 to 1500 MW (Nairn, 1981), means that the heat lost horizontally is likely much less than that lost vertically. This implies that the Kaharoa magma chamber was likely lens shaped. The temperature at the top of the chamber would be controlled by the amount of heat that groundwater circulation is able to dissipate (related to the boiling temperature and permeability). The sidewalls of the Kaharoa chamber have only conduction to carry away heat, and as this mechanism is relatively inefficient compared to roof cooling (convection), it would likely be possible to melt country rock at the sides of the chamber over time. This would enhance a lens-like shaped chamber.  2.5.6. Caveats with the method There are a few improvements or changes that I could make with the current methodology to allow it to be universally applicable to other rocks. I only examine crystals from the loose crystal population. Whereas this gives a random sample of the entire population, it could be interesting to examine crystals from the rhyolites and basalts separately, or crystals from lavas and intrusive rocks. This could be accomplished with the addition of a crystal separation technique. I tried light crushing with a chipmunk-style crusher, followed by sieving and separation of the crystals. However, my starting population of plagioclase crystals in the Kaharoa eruptives consisted of already existing broken crystals, and this technique resulted in more breakage and overall destruction of the crystal population. This same separation  67  technique might be appropriate with other juvenile volcanic rocks or one could try Electric Pulse Disaggregation (EPD) methods (Rudashevsky et al., 1995; Bindeman, 2005) as they might be a gentler option for crystal liberation. Bindeman (2005) found that EPD failed to separate phenocrysts from glass in a welded tuff, however, most of the crystals used in this study had glass “jackets” that did not inhibit their use, so this may still be a viable option. A further improvement is to include orientation data for the crystals. I oriented the crystals prior to mounting them in the epoxy pucks, but expect that some wobble is possible as a result of pouring the epoxy. Possible techniques for determining exact orientations of crystals relative to the prepared measurement surface include Electron Backscatter Diffraction (EBSD) (e.g. Xie et al., 2003) or use of a Universal stage (e.g., Greenwood and McTaggert, 1957; Wiebe, 1968). EBSD is an electron beam method and requires a very finely polished surface on thin sections or epoxy disks, and the input of crystal lattice parameters into software that computes the crystal orientation. Universal stage methods require the samples to be in thin sections. This orientation data would allow for direct comparison between crystals, with a geometric correction for any skewing caused by off-axis measurements. However, for this study I choose to exclude these methods as no direct correlations were made between crystals and the crystals were reasonably well oriented with respect to the measurement surfaces. Finally, with longer etching I expect that even better resolution of ‘events’ using NDIC methods could be achieved, in comparison to BSE imaging, especially with the ‘Small variation’ crystal group. For crystals with small differences in anorthite content, image quality could be improved with longer etching. This would create a deeper  68  ‘topography’ on the crystal surface, and make even small ‘events’ easier to detect and image. In addition, coating the crystal pucks with gold or gold-palladium instead of carbon may lead to better image quality because of increased reflectivity.  2.6.  Conclusions and future work I have developed a new methodology for characterising zoning in plagioclasse  crystals. This technique builds upon work by Ginibre et al. (2002) and Wallace and Bergantz (2002, 2004, 2005). I focus on determining how to make observations of zoning present in populations of crystals, and specifically look at two deposits from the Kaharoa eruption of Tarawera Volcano, NZ. I achieve similar or better spatial resolution to that of Ginibre et al. (2002) and, in principle, using the Nomarski technique, I could extend resolution to the atomic level. With the current dataset, I identify one or more periods of zoning within a 3.1–12.4 µm bandwidth common to most crystals. In addition, I demonstrate that zoning varies with direction, consistent with expectations that diffusivities vary with crystallographic orientation. If plagioclase zoning is related to periodic variations in temperature, then convection preceding the Kaharoa eruption was characterised by motions acting over time scales of 39 days to 1.8 years. The variations in anorthite content I observe are mostly small (~5 mol % An differences across a crystal), which correspond to the modest temperature variations that convection is able to carry. I also find few examples of crystals that have experienced discrete events leading to large variations in mol % An. In combination, these observations lead to the interpretation that the Kaharoa eruption was 69  not caused by a discrete mixing event. In future work, determination of the scale of the temperature and/or H2O variations experienced by crystals could lead to models that are better able to constrain pre-eruption magmatic conditions. The current EMPA and BSE datasets imply that the temperature variations were small. However, I would like to make a rigorous mapping between Nomarski topography and absolute (or relative) mol % An (e.g. Pearce, 1984b). Also of interest are the trace element and lead isotope variations that might occur across individual crystals, and the possible differences that might exist along different crystallographic axes. The various trace elements will have different diffusion rates to those of CaA-NaSi, and may reveal additional timescales involved in the growth of the Kaharoa plagioclase crystals. Isotopes are not expected to fractionate differently with changes in temperature, pressure, and H2O content, and would thus be good indicators of whether individual crystals were in contact, and growing in multiple magmas, thereby mixing mechanically.  70  CHAPTER 3: Concluding remarks  This work provides a means for obtaining important constraints on magma chamber dynamics through observations of plagioclase zoning. I am able to detect quasiperiodic zoning occurring at a range of length scales, as well as discrete, non-periodic events. Combined, these quantitative and qualitative results allow specific questions to be asked, with testable hypotheses, regarding the pre-eruptive state of a given magma chamber. If plagioclase crystals are indeed ‘Lagrangian tracers’ and record the environments in which they grow, then I can determine what the ‘average’ plagioclase crystal experiences in terms of growth conditions, and evaluate departures from this basic state. These crystals can be used to determine the extent to which basalt injections, that commonly preceded eruption, may have thermally or mechanically mixed with the host magma. Eruptions, such as the AD 1315 Kaharoa eruption of Tarawera Volcano, New Zealand, may be caused by a series of small basaltic inputs, as opposed to a single catastrophic injection of hot basalt. This eruption was characterised by most plagioclase crystals, erupted at the so-called mixing horizon (Leonard et al., 2002; Nairn et al., 2004), having only small changes in anorthite content across the crystals. A few, <30 %, had zoning with large changes in anorthite (>3-4%) between zones. These few crystals may have mechanically mixed with an injected basalt, but the majority, the ‘basic state’ crystals likely did not. Finally, eruptions such as Kaharoa are likely preceded by thermal mixing, giving rise to oscillatory zoning in plagioclase crystals. However, enhanced thermal mixing was not found here unless all of the oscillatory zoned growth was in 71  response to this enhanced thermal mixing condition. Future work could be directed towards deconvolving signals of distinct chemistry melts and changes in intensive parameters. Trace element and isotope work could reveal additional timescales of magma chamber processes and interaction (and growth) of crystals with differing melt compositions. This work could elucidate important clues into the cause of explosive eruptions that do not seem to have extensive mechanical mixing signatures. Another potential direction of study might focus on the mapping between topography of Nomarksi etched crystals and major element chemical composition. Historically, this mapping has been largely qualitative (e.g. textural similarities) and based on very sparse chemical (EMPA) data. Application of statistical techniques recently developed for analysing global paleomagnetic datasets (Ziegler et al., 2008) to this problem could be a major advance over existing data analysis techniques.  72  REFERENCES Allègre, C.J., Provost, A., Jaupart, C. 1981. Oscillatory zoning: a pathological case of crystal growth. Nature, 294, 223-228. Anderson, A.T. Jr. 1984. Probable relations between plagioclase zoning and magma dynamics, Fuego Volcano, Guatemala. American Mineralogist, 69, 660-676. Anderson, A.T. Jr. 1983. Oscillatory zoning of plagioclase: Nomarski interference contrast microscopy of etched polished sections. American Mineralogist, 68, 125-129. Armienti, P., Pareschi, M.T., Innocenti, F., Pompilio, M. 1994. Effects of magma storage and ascent rates on the kinetics of crystal growth. Contributions to Mineralogy and Petrology, 115, 402-414. Bacon, C.R. 1986. Magmatic inclusions in silicic and intermediate volcanic rocks. Journal of Geophysical Research, 91(B6), 6091-6112. Bachl, C.A., Miller, C.F., Miller, J.S., Faulds, J.E. 2001. Construction of a pluton: Evidence from an exposed cross section of the Searchlight pluton, Eldorado Mountains, Nevada. Geological Society of America Bulletin, 113, 1213-1228. Bachmann, O., Dungan, M.A., Lipman, P.W. 2002. The Fish Canyon magma body, San Juan Volcanic Field, Colorado: Rejuvenation and eruption of an upper-crustal batholith. Journal of Petrology, 43, 1469-1503. Bachmann, O., Miller, C.F., De Silva, S.L. 2007. The volcanic-plutonic connection as a stage for understanding crustal magmatism. Journal of Volcanology and Geothermal Research, 167, 1-23. Barclay, J., Rutherford, M.J., Carroll, M.R., Murphy, M.D., Devine, J.D., Gardner, J., Sparks, R.S.J. 1998. Experimental phase equilibria constraints on pre-eruptive storage conditions of the Soufriere Hills magma. In: Aspinall, W.P. et al. (Eds.), The Soufriere Hills eruption, Montserrat, British West Indies; Introduction to special section; Part 1. Geophysical Research Letters, 25, 3437-3440. Baschek, G., Johannes, W. 1995. The estimation of NaSi-CaAl interdiffusion rates in peristerite by homogenization experiments. European Journal of Mineralogy, 7, 295-307. Bergantz, G.W., Ni, J. 1999. A numerical study of sedimentation by dripping instabilities in viscous fluids. International Journal of Multiphase Flow, 25, 2, 307-320.  73  Bindeman, I.N. 2003. Crystal sizes in evolving silicic magma chambers. Geology, 31, 367-370. Bindeman, I.N. 2005. Fragmentation phenomena in populations of magmatic crystals. American Mineralogist, 90, 1801-1815. Bindeman, I.N., Bailey, J.C. 1994. A model of reverse differentiation at Dikii Greben’ Volcano, Kamchatka: progressive basic magma vesiculation in a silicic magma chamber. Contributions to Mineralogy and Petrology, 117, 263-278. Blake, S. 1981. Volcanism and the dynamics of open magma chambers. Nature, 89, 783– 785. Blundy, J., Cashman, K.V. 2001. Ascent-driven crystallization of dacite magmas at Mount St. Helens, 1980-1986. Contributions to Mineralogy and Petrology, 140, 631-651. Bottinga, Y., Kudo, A., Weill, D. 1966. Some observations on oscillatory zoning and crystallization of magmatic plagioclase. American Mineralogist, 51, 792-806. Bowen, N.L. 1913. The melting phenomena of the plagioclase feldpars. American Journal of Science, Series 4, 35, 577-599. Castro, J. M., Cashman, K. V., Manga, M. 2003. A technique for measuring 3D crystalsize distributions of prismatic microlites in obsidian. American Mineralogist, 88, 1230–1240. Cherniak, D.J. 1995. Diffusion of lead in plagioclase and K-feldspar: an investigation using Rutherford Backscattering and Resonant Nuclear Reaction Analysis. Contributions to Mineralogy and Petrology, 120, 358-371. Clark, A.H., Pearce, T.H., Roeder, P.L., Wolfson, I. 1986. Oscillatory zoning and other microstructures in magmatic olivine and augite: Nomarski interference contrast observations on etched polished surfaces: American Mineralogist, 71, 734-741. Clynne, M.A. 1999. A complex magma mixing origin for rocks erupted in 1915, Lassen Peak, California. Journal of Petrology, 40, 105-132. Collins, W.J., Wiebe, R.A., Healy, B., Richards, S.W. 2006. Replenishment, crystal accumulation and floor aggradation in megacrystic Kameruka suite, Australia. Journal of Petrology, 47, 2073-2104. Couch, S. 2003. Experimental investigation of crystallization kinetics in a haplogranite system. American Mineralogist, 88, 1471-1485.  74  Couch, S., Sparks, R.S.J., Carroll, M.R. 2001. Mineral disequilibrium in lavas explained by convective self-mixing in open magma chambers. Nature, 411, 1037–1039. Davaille, A. and Jaupart, C. 1993. Transient high-Rayleigh-number thermal convection with large viscosity variations. Journal of Fluid Mechanics, 253, 141. Deer, W.A., Howie, R.A., Zussman, J. 1966. An introduction to the rock forming minerals. England, Longman, 528p. Donaldson, C.H. 1985. The rates of dissolution of olivine, plagioclase, and quartz in basalt melt. Mineralogical Magazine, 49, 683-693. Drake, M.J. 1976. Plagioclase equilibria. Geochimica et Cosmochimica Acta, 40, 457465. Dresen, G., Wang, Z., Bai, Q. 1996. Kinetics of grain growth in anorthite. Tectonophysics, 258, 251-262. Eichelberger, J.C. 1980. Vesiculation of mafic magma during replenishment of silicic magma reservoirs. Nature, 288, 446-450. Emmons, R.C. 1943. The universal stage. Geological Society of America Memoirs, 8, 205 p. Falkner, C.M., Miller, C.F., Wooden, J.L., Heizler, M.T. 1995. Petrogenesis and tectonic significance of the calc-alkaline, bimodal Aztec Wash pluton, Eldorado Mountains, Colorado River extensional corridor. Journal of Geophysical Research, 100, 10,453–10,476. Folch, A., Marti, J. 1998. The generation of overpressure in felsic magma chambers by replenishment. Earth and Planetary Science Letters, 163, 301-314 Fowler, A., Prokoph, A., Stern, R., Dupuis, C. 2002. Organization of oscillatory zoning in zircon: analysis, scaling, geochemistry, and model of a zircon from Kipawa, Quebec, Canada. Geochimica et Cosmochimica Acta, 66(2), 311–328. Gerlach, D.C., Grove, T.L. 1982. Petrology of Medicine Lake Highland volcanics: Characterization of endmembers of magma mixing. Contributions to Mineralogy and Petrology, 80, 147-159. Ghiorso, M.S., Sack, R.O. 1991. Fe–Ti oxide geothermometry: thermodynamic formulation and estimation of intensive variables in silicic magmas. Contributions to Mineralogy and Petrology, 108, 485–510.  75  Ginibre, C., Kronz, A., Wörner, G. 2002. High-resoultuion quantitative imaging of plagioclase composition using accumulated backscattered electron images: new constraints on oscillatory zoning. Contributions to Mineralogy and Petrology, 142, 436-448. Greenwood, H. J. and McTaggart, K. C. 1957. Correlation of zones in plagioclase. American Journal of Science, 255, 656-666. Grove, T.L., Baker, M.B., Kinzler, R.J. 1984. Coupled CaAl-NaSi diffusion in plagioclase feldspar: Experiments and applications to cooling rate speedometry. Geochimica et Cosmochimica Acta, 48 (10), 2113-2121. Harper, B.E., Miller, C.F., Koteas, G.C., Gates, N.L., Wiebe, R.A., Lazzareschi, D.S., Cribb, J.W. 2004. Granites, dynamic magma chamber processes and pluton construction: the Aztec Wash pluton, Eldorado Mountains, Nevada, USA. Transactions of the Royal Society of Edinburgh. Earth Sciences, 95 (1-2), 277296. Healy, J., Schofield, J. C., Thompson, B. N. 1964. Sheet 5 — Rotorua. Geological map of New Zealand 1:250 000. Wellington, Department of Scientific and Industrial Research. Holland, T., Blundy, J. 1994. Non-ideal interactions in calcic amphiboles and their bearing on amphibole-plagioclase thermometry. Contributions to Mineralogy and Petrology, 116(4), 433-447. Housh, T.B., Luhr, J.F. 1991. Plagioclase – melt equilibria in hydrous systems. American Mineralogist, 76, 477-492. Irvine, T.N. 1970. Heat transfer during solidification of layered intrusions. I. Sheets and sills. Canadian Journal of Earth Science, 7, 1031-1061. Izbekov, P.E., Eichelberger, J.C., Patino, L.C., Vogel, T.A. 2002. Calcic cores of plagioclase phenocrysts in andesite from Karymsky volcano: evidence for rapid introduction by basaltic replenishment. Geology 30(9), 799–802. Jaupart, C., Tait, S. 1995. Dynamics of differentiation in magma reservoirs. Journal of Geophysical Research, 100, B9, 17615-17636. Jellinek, A.M., Kerr, R.C. 2001. Magma dynamics, crystallization, and chemical differentiation of the 1959 Kilauea Iki lava lake, Hawaii, revisited. Journal of Volcanology and Geothermal Research, 110 (3-4), 235-263. Jellinek, A.M., Kerr, R.C. 1999. Mixing and compositional stratification produced by natural convection: 2. Applications to the differentiation of basaltic and silicic  76  magma chambers and komatiite lava flows. Journal of Geophysical Research, 104 (B4), 7203-7218. Johannes, W. 1978. Melting of plagioclase in the system Ab-An-H2O and Qz-Ab-AnH2O at PH O=5 kbars, an equilibrium problem. Contributions to Mineralogy and Petrology, 66, 295-304. 2  Johnson, M.C., Rutherford, M.J. 1989. Experimental calibration of the aluminum-inhornblende geobarometer with application to Long Valley caldera (California) volcanic rocks. Geology, 17 (9), 837-841. Kouchi, A., Sunagawa, I. 1985. A model for basaltic and dacitic magmas as deduced from experimental data. Contributions to Mineralogy and Petrology, 89, 17-23. Koyaguchi, T., Blake, S. 1989. The dynamics of magma mixing in a rising batch. Bulletin of Volcanology, 52, 127-137. Kudo, A.M., Weill, D.F. 1970. An igneous plagioclase thermometer. Contributions to Mineralogy and Petrology, 25, 52-65. Leonard, G.S., Cole, J.W., Nairn, I.A., Self, S. 2002. Basalt triggering of the c. AD 1305 Kaharoa rhyolite erution, Tarawera Volcanic Complex, New Zealand. Journal of Volcanology and Geothermal Research, 115, 461-486. L’Heureux, I., Fowler, A.D. 1996. Isothermal constitutive undercooling as a model for oscillatory zoning in plagioclase. Canadian Mineralogist, 34, 1137-1147. Lindline. J., Crawford, W.A., Crawford, M.L. 2004. A bimodal volcanic-plutonic system: the Zarembo Island extrusive suite and the Burnett Inlet intrusive complex. Canadian Journal of Earth Science, 41, 355-375. Lindsley, D.H. 1968. Melting relations of plagioclase at high pressures. In Y. W. Isachsen (Ed.), Origin of anorthosite and related rocks. New York State Museum and Science Service, Memoir 18, 39-46. Lofgren, G. 1974. An experimental study of plagioclase crystal morphology: isothermal crystallization. American Journal of Science, 274, 243-273. Lofgren, G. 1980. Experimental studies on the dynamic crystallization of silicate melts. R.B. Hargraves (Ed.), The Physics of Magmatic Processes, Princeton University Press, pp. 487-551. Loomis, T.P. 1981. An investigation of disequilibrium growth processes of plagioclase in the system anorthite-albite-water by methods of numerical simulation. Contributions to Mineralogy and Petrology, 76, 196-205.  77  Loomis, T.P. 1982. Numerical simulations of crystallization processes of plagioclase in complex melts: the origin of major and oscillatory zoning in plagioclase. Contributions to Mineralogy and Petrology, 81, 219-229. Mahood, G.A. 1990. Second reply to comment of R.S.J. Sparks, H.E. Huppert and C.J.N. Wilson on ``Evidence for long residence times of rhyolitic magma in the Long Valley magmatic system: the isotopic record in the precaldera lavas of Glass Mountain''. Earth and Planetary Science Letters, 99, 395-399. Manga, M., Weeraratne, D., Morris, S.J.S. 2001. Boundary-layer thickness and instabilities in Bénard convection of a liquid with a temperature-dependent viscosity. Physics of Fluids, 13 (3), 802-806. Marsh, B. D. 1988. Crystal capture, sorting, and retention in convecting magma. Geological Society of America Bulletin, 100, 1720 – 1737. Martin, D., Griffiths, R.W., Campbell, I.H. 1987. Compositional and thermal convection in magma chambers. Contributions to Mineralogy and Petrology, 96, 465-475. Miller, C.F., Miller, J.S. 2002. Contrasting stratified plutons exposed in tilt blocks, Eldorado Mountains, Colorado River Rift, NV, USA, Lithos, 61, 209–224. Mock, A., Jerram, D.A. 2005. Crystal size distributions (CSD) in three dimensions: insights from the 3D reconstruction of a highly porphyritic rhyolite. Journal of Petrology, 46 (8), 1525-1541. Murphy, M.D., Sparks, R.S.J., Barclay, J., Carroll, M.R., Brewer, T.S. 2000. Remobilization of andesitic magma by intrusion of mafic magma at the Soufrière Hills Volcano, Montserrat, West Indies. Journal of Petrology, 41, 21–42. Nairn, I.A. 2002. Geology of the Okataina Volcanic Centre, scale 1:50,000. Institute of Geological & Nuclear Sciences Geological Map 25. (1 sheet plus 156 pp). Lower Hutt, New Zealand: Institute of Geological & Nuclear Sciences Ltd. Nairn, I.A. 1989. Geological Map of New Zealand, Sheet V16AC Tarawera. Department of Scienctific and Industrial Research, Wellington, New Zealand. Nairn I.A., Shane, P.R., Cole, J.W., Leonard, G.J., Self, S., Pearson, N. 2004. Rhyolite magma processes of the ~AD 1315 Kaharoa eruption episode, Tarawera volcano, New Zealand. Journal of Volcanology and Geothermal Research, 131, 265-294. Nairn, I.A., Self, S., Cole, J.W., Leonard, G.S., Scutter, C. 2001. Distribution, stratigraphy and history of proximal deposits from the c. AD 1305 Kaharoa eruptive episode at Tarawera volcano, New Zealand. New Zealand Journal of Geology and Geophysics, 44, 467-484.  78  Nicholls, I.A., Oba, T., Conrad, W.K. 1992. The nature of primary rhyolite magmas involved in crustal evolution: evidence from an experimental study of cummingtonite-bearing rhyolites, Taupo volcanic zone, New Zealand. Geochimica et Cosmochimica Acta, 56, 955–962. Nomarski, G., Weill, A.R. 1954. Sur l’observation des figures de croissance des cristaux par les methodes interferentielles a deux ondes. Bulletin de la Société Francaise de Minéralogie et de Cristallographie, 78, 840-868. Nomarski, G., Weill, A.R. 1955. Application à la métallographie des méthodes interférentielles à deux ondes polarisées. Revue de Métallurgie, 2, 121–128. Pallister, J.S., Hoblitt, R.P., Reyes, A.G. 1992. A basalt trigger for the 1991 eruptions of Pinatubo volcano. Nature, 356, 426-428. Pearce, T.H. 1984a. Optical dispersion and zoning in magmatic plagioclase: laserinterference observations. Canadian Mineralogist, 22, 383–390. Pearce, T. H. 1984b. The analysis of zoning in magmatic crystals with emphasis on olivine. Contributions to Mineralogy and Petrology, 86, 149–154. Pearce, T.H. 1994. Recent work on oscillatory zoning in plagioclase. In: Parson I (ed) Feldspars and Their Reactions. Kluwer, Dordrecht, pp 313-349. Pearce, T.H., Kolisnik, A.M. 1990. Observation of plagioclase zoning using interference imaging. Earth Science Reviews, 29, 9-26. Pearce, T.H., Russell, J.K., Wolfson, I. 1987. Laser interference and Nomarski interference imaging of zoning profiles in plagioclase phenocrysts from the May 18, 1980, eruption of Mount St Helens, Washington. American Mineralogist, 72, 1131–1143. Perugini, D., Little, M., Giampiero, P. 2006. Time series to petrogenesis: analysis of oscillatory zoning patterns in plagioclase crystals from lava flows. Periodico di Mineralogia, 75, 2-3, 263-276. Philpotts, A.R., Carroll, M. 1996. Physical properties of partly melted tholeiitic basalt. Geology, 24, 1029-1032. Pons, J., Barbey, P., Nachit, H., Burg, J.P. 2006. Development of igneous layering during growth of pluton: the Tarcouate Laccolith (Morocco). Tectonophysics, 413, 271–286. Pringle, G.J., Tembeth, L.T., Pajari, G.J. Jr. 1974. Crystallization history of a zoned plagioclase. Mineralogical Magazine, 39, 867-877.  79  Richnow, J. 2000. Eruptional and post-eruptional processes in rhyolite domes. Unpublished Ph.D. dissertation, University of Canterbury, Christchurch, 545 pp. Rudashevsky, N.S., Burakov, B.E., Lupal, S.D., Tralhammer, O.A.R. 1995. Liberation of accessory minerals from various rock types by electric-pulse disintegration – method and application. Transactions of the Institution of Mining and Metallurgy. Section C. Mineral Processing and Extractive Metallurgy, 104, C259. Ruprecht, P., Bergantz, G.W., Dufek, J. 2008. Modeling of gas-driven magmatic overturn: Tracking of phenocryst dispersal and gathering during magma mixing. Geochemistry Geophysics Geosystems, 9, 7, doi:10.1029/2008GC002022 Sahagian, D. L., Proussevitch, A. A. 1998. 3D particle size distributions from 2D observations: Stereology for natural applications. Journal of Volcanology and Geothermal Research 84, 173–196. Sakuyama, M. 1981. Petrological study of the Myoko and Kurohime volcanoes, Japan: crystallisation sequence and evidence for magma mixing. Journal of Petrology, 22, 553-583. Shane, P. 1998. Correlation of rhyolitic pyroclastic eruptive units for the Taupo volcanic zone by Fe–Ti oxide compositional data. Bulletin of Volcanology, 60, 224–238. Singer , B.S., Dungan, M.A., Layne, G.D. 1995. Textures and Sr, Ba, Mg, Fe, K, and Ti compositional profiles in volcanic plagioclase: clues to the dynamics of calcalkaline magma chambers. American Mineralogist, 80, 776-798. Sisson, T.W., Grove, T.L. 1993. Experimental investigations of the role of H2O in calcalkaline differentiation and subduction zone magmatism. Contributions to Mineralogy and Petrology, 113, 143-166. Sparks, R.S.J., Marshall, L.A. 1986. Thermal and mechanical constraints on mixing between mafic and silicic magmas. Journal of Volcanology and Geothermal Research, 29, 99-124. Sparks, R.S.J., Sigurdsson, H., Wilson, L. 1977. Magma mixing: A mechanism for triggering acid explosive eruptions. Nature, 267, 315-318. Snyder, D. 2000. Thermal effects of the intrusion of basaltic magma into a more silicic magma chamber and implications for eruption triggering. Earth and Planetary Science Letters, 175, 257-273. Snyder, D., Tait, S. 1995. Replenishment of magma chambers: comparison of fluidmechanic experiments with field relations. Contributions to Mineralogy and Petrology, 122, 230-240.  80  Snyder, D., Tait, S. 1996. Magma mixing by convective entrainment. Nature, 379, 529531. Solomatov, V.S. 1995. Scaling of temperature- and stress-dependent viscosity convection. Physics of Fluids, 7, 266. Stamatelopoulou-Seymour, K., Vlassopoulos, D., Pearce, T.H., Rice, T. 1990. The record of magma chamber processes in plagioclase phenocrysts at Thera Volcano, Aegean Volcanic Arc, Greece. Contributions to Mineralogy and Petrology, 104, 73-84. Tait, S., Jaupart, C., Vergniolle, S. 1989. Pressure, gas content and eruption periodicity of a shallow, crystallizing magma chamber. Earth and Planetary Science Letters, 92, 107-123. Tefend, K.S., Vogel, T.A., Flood, T.P., Ehrlich, R. 2007. Identifying relationships among silicic magma batches by polytopic vector analysis: A study of the Topopah Spring and Pah Canyon ash-flow sheets of the southwest Nevada volcanic field. Journal of Vocanology and Geothermal Research, 167, 198-211. Tepley III, F.J., Davidson, J.P, Tilling, R.I., Arth, J.G. 2000. Magma mixing, recharge and eruption histories recorded in plagioclase phenocrysts from El Chichon Volcano, Mexico. Journal of Petrology, 41, 6, 1397-1411. Thomson, D.J. 1982. Spectrum estimation and harmonic analysis. Proceedings of the Institute of Electrical and Electronics Engineers, 70, 9. Turnbull, R., Weaver, S., Tulloch, A., Cole, J., Handler, M., Ireland, T. 2010. Field and geochemical constraints on mafic–felsic interactions, and processes in high-level arc magma chambers: an example from the Halfmoon Pluton, New Zealand. Journal of Petrology, in press, doi:10.1093/petrology/egq026 Turner, J.S., Campbell, I.H. 1986. Convection and mixing in magma chambers. Earth Science Reviews, 23, 255-352. Tsuchiyama, A. 1985. Dissolution kinetics of plagioclase in the melt of the system diopside-albite-anorthite, and origin of dusty plagioclase in andesites. Contributions to Mineralogy and Petrology, 89, 1-16. Vance, J.A. 1965. Zoning in igneous plagioclase: patchy zoning. Journal of Geology, 73, 637–651. Venezky, D.Y., Rutherford, M.J. 1997. Preeruption conditions and timing of dacite– andesite magma mixing in the 2.2 ka eruption at Mount Rainer. Journal of Geophysics Research, 102, 20069–20086.  81  Wallace, G.S., Bergantz, G.W. 2005. Reconciling heterogeneity in crystal zoning data: An application of shared characteristic diagrams at Chaos Crags, Lassen Volcanic Center, California. Contributions to Mineralogy and Petrology, 149, 98–112. Wallace, G.S., Bergantz, G.W. 2004. Constraints on mingling of crystal populations from off-center zoning profiles: a statistical approach. American Mineralogist, 89(2), 64–73. Wallace, G.S., Bergantz, G.W. 2002. Wavelet-based correlation (WBC) of crystal populations and magma mixing. Earth and Planetary Science Letters, 202, 133145. Watson, E.B. 1994. Diffusion in volatile-bearing magmas. Reviews in Mineralogy and Geochemistry, 30 (1), 371-411. Welch, P.D. 1967. The use of fast fourier transform for the estimation of power spectra: A method based on time averaging over short, modified periodograms. Institute of Electrical and Electronics Engineers, Transactions on Audio and Electroacoustics, AU-15, 2. Wilson, C. J. N., Houghton, B. F., McWilliams, M. O., Lanphere, M. A., Weaver, S. D., Briggs, R. M. 1995. Volcanic and structural evolution of Taupo Volcanic Zone, New Zealand: a review. Journal of Volcanology and Geothermal Research 68, 1– 28. Wiebe, R. A. 1968. Plagioclase stratigraphy: a record of magmatic conditions and events in a granite stock. American Journal of Science, 266, 690-703. Wiebe, R. A. 1993. The Pleasant Bay layered gabbro-diorite, Coastal Maine: Ponding and crystallization of basaltic injections into a silicic magma chamber. Journal of Petrology, 34, Part 3, 461-489. Wiebe, R.A., Collins, W.J. 1998. Depositional features and stratigraphic sections in granitic plutons: implications for the emplacement and crystallization of granitic magma. Journal of Structural Geology, 20, 1273–1289. Wiebe, R.A., Blair, K.D., Hawkins, D.P. Sabine, C.P. 2002. Mafic injections, in situ hybridization, and crystal accumulation in the Pyramid Peak granite, California. Geological Society of America Bulletin, 114, 909–920. Wolf, K.J., Eichelberger, J.C. 1997. Syneruptive mixing, degassing, and crystallisation at Redoubt Volcano, eruption of December, 1989 to May 1990. Journal of Volcanology and Geothermal Research, 75, 19–37.  82  Xie,Y., Wenk, H-R., Matthies, S. 2003. Plagioclase preferred orientation by TOF neutron diffraction and SEM-EBSD. Tectonophysics, 370, 269-286. Yoder, H.S., Stewart, D.B., Smith, J.R. 1957. Ternary feldspars. Carnegie Institute of Washington Yearbook, 56, 206-214. Ziegler, L.B., Constable, C., Johnson, C.L., Tauxe, L. 2008. PADM2M: A time-varying model of paleomagnetic axial dipole moment for 0-2 Ma. Eos Transactions. AGU, 89, 53, Fall Meeting Supplement, Abstract GP21A-0774.  83  APPENDIX A: Sample location map  Figure 19. Map of the Tarawera Volcanic Complex, New Zealand with all sample locations.  84  APPENDIX B: Sample inventory Table A1. Sample inventory. Sample  Eruption  MJ-06-01 MJ-06-02 MJ-06-03 MJ-06-04 MJ-06-05 MJ-06-06 MJ-06-07 MJ-06-08 MJ-06-09 MJ-06-10 MJ-06-11 MJ-06-11 MJ-06-12 MJ-06-13 MJ-06-14 MJ-06-15 MJ-06-16 MJ-06-17 MJ-06-18 MJ-06-19 MJ-06-20 MJ-06-21 MJ-06-22 MJ-06-23 MJ-06-25 MJ-06-26 MJ-06-27 MJ-06-28  Kaharoa Kaharoa Tarawera Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa? Kaharoa? Kaharoa Kaharoa Kaharoa Kaharoa/Tarawera Kaharoa Kaharoa Kaharoa Tarawera? Tarawera? Kaharoa/Tarawera Kaharoa/Tarawera Kaharoa/Tarawera Kaharoa Kaharoa Kaharoa Kaharoa  Eruption unit HPDC B&A  Deposit type pflow b&a  D F B B F? G? M? DOME DOME DOME DOME DOME  tephra tephra tephra tephra tephra tephra tephra dome lava dome lava dome lava dome lava dome lava  DOME Ben's FLOAT FLOAT  dome lava  Location S38 16.392' E176 30.870' S38 16.392' E176 30.870' S38 16.392' E176 30.870' S38 16.756' E176 30.769' S38 16.756' E176 30.769' S38 16.756' E176 30.769' S38 18.559' E176 31.873' S38 18.559' E176 31.873' S38 18.559' E176 31.873' S38 13.583' E176 30.678' S38 13.583' E176 30.678' S38 13.583' E176 30.678' S38 13.684' E176 30.463' S38 13.665' E176 30.448' S38 13.672' E176 30.435' S38 13.640' E176 30.429' S38 13.709' E176 30.385'  S38 13.751' E176 30.363'  H I J K  tephra tephra tephra tephra  S38 7.545' E176 31.222' S38 7.545' E176 31.222' S38 7.545' E176 31.222' S38 7.545' E176 31.222'  85  Thin section? YES YES YES YES YES YES YES YES YES YES YES  TS Name  Type  MJ-06-01 MJ-06-11A MJ-06-11B MJ-06-12 MJ-06-14 MJ-06-15 MJ-06-16 MJ-06-17 MJ-06-25 MJ-06-26 MJ-06-28  rock rock rock rock rock rock rock rock grain mount grain mount grain mount  Crystals picked? yes yes yes  Table A1 continued. Sample inventory. Sample  Eruption  MJ-06-29 MJ-06-30 MJ-06-31 MJ-06-32 MJ-06-33 MJ-06-34 MJ-06-35 MJ-06-36 MJ-06-37 MJ-06-37 MJ-06-37 HW-06-01 HW-06-02 HW-06-02 HW-06-03 HW-06-03 HW-06-04 HW-06-05 HW-06-05 HW-06-05 HW-06-06 HW-06-07 HW-06-08 HW-06-09 HW-06-09 HW-06-10 HW-06-10 HW-06-11 HW-06-11 HW-06-12 HW-06-13 HW-06-14  Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Tarawera Tarawera Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa Kaharoa  Eruption unit L H J K L M top bottom HPDC HPDC HPDC F HPDC HPDC HPDC HPDC H HPDC HPDC HPDC HPDC HPDC B&A B&A B&A B&A B&A B&A B&A B&A HPDC H?  Deposit type tephra tephra tephra tephra tephra tephra  Location S38 7.545' E176 31.222' S38.9.361' E176 35.603' S38.9.361' E176 35.603' S38.9.361' E176 35.603' S38.9.361' E176 35.603' S38.9.361' E176 35.603' S38.9.361' E176 35.603' S38.9.361' E176 35.603'  pflow pflow pflow tephra pflow pflow pflow pflow tephra pflow pflow pflow pflow pflow dome lava dome lava dome lava dome lava dome lava dome lava dome lava dome lava pflow tephra  V16/176195 V16/176195 V16/176195 V16/176195 V16/217244 V16/217244 V16/217244 V16/217244 V16/217244 V16/176180 V16/176180 V16/176180 V16/176180 V16/176180 V16/176180 V16/176180 V16/176180 V16/176180 V16/136203 V16/136203  86  Thin section? YES YES YES YES YES YES YES YES YES YES YES YES YES -  TS Name  Type  MJ-06-30 MJ-06-32 MJ-06-37A MJ-06-37B MJ-06-37C HW-06-02A HW-06-02B HW-06-03A HW-06-03B HW-06-05A HW-06-05B HW-06-05C HW-06-08 HW-06-09A HW-06-09B HW-06-10A HW-06-10B HW-06-11A HW-06-11B HW-06-12 -  grain mount grain mount rock rock rock rock rock rock rock rock rock rock rock rock rock rock rock rock rock rock -  Crystals picked? yes yes yes yes -  Table A1 continued. Sample inventory. Sample  Eruption  HW-06-15  Kaharoa  Eruption unit H?  Deposit type tephra  Location V16/136203  87  Thin section? -  TS Name  Type  -  -  Crystals picked? -  APPENDIX C: Crystal indexing Crystals in each sample (HW0604 and HW0607) are named such that the first number is the sample number (4 or 7), the next three numbers are the size fraction that the crystal belongs to (2-1, 1-0.595, 0.595-0.420, or 0.420-0.350 mm), and the last two numbers refer to the crystal number within that size fraction. Example,  7 – 435 – 09  sample number HW0607  size fraction 0.420-0.350 mm  88  crystal number #9  APPENDIX D: Crystal inventory The crystal inventory below is for samples HW0604 and HW0607. I have listed the size fraction that each crystal belongs to, as well as the textural/compositional (zoning group) grouping and all analyses performed on individual crystals. The zoning groups are described in Table 1 of the main text. The abbrviations that I have used are as follows: D  dramatic zoning (some zoning visible in original BSE image)  S  subtle zoning (no zoning visible in original BSE image)  The ‘dramatic’ grouping is further divided into: H  high contrast  M  medium contrast  L  low contrast  Then, the ‘high contrast’ group is divided into the following groupings: P  patchy  PC  patchy cores  CC  calcic cores  A  alternating  SR  sodic rims  89  Table A2. Crystal inventory for samples HW0604 and HW0607 Sample  Size fraction  No.  Name  Type  Glass coat?  Zoning group  HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604  (mm) 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350  1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18  4-4-3501 4-4-3502 4-4-3503 4-4-3504 4-4-3505 4-4-3506 4-4-3507 4-4-3508 4-4-3509 4-4-3510 4-4-3511 4-4-3512 4-4-3513 4-4-3514 4-4-3515 4-4-3516 4-4-3517 4-4-3518  plag plag plag plag plag plag plag plag plag plag plag plag plag plag plag plag glass plag  yes yes yes no yes yes yes no yes yes yes yes yes yes yes yes yes  D S D D D S D D D S S S D D D S S  H M H H H H H H M H -  P PC CC CC PC A PC A -  HW0604  0.420-0.350  19  4-4-3519  plag  yes  D  M  -  HW0604 HW0604 HW0604 HW0604  0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350  20 21 22 23  4-4-3520 4-4-3521 4-4-3522 4-4-3523  glass glass plag plag  yes yes  S S  -  -  90  EMPA  Trace elements  Isotopes  points points points traverse points 2 traverses -  points & traverse points points & traverse points & traverse points points & traverse points & traverse -  yes yes -  -  -  -  -  Table A2 continued. Crystal inventory for samples HW0604 and HW0607. Sample  Size fraction  No.  Name  Type  Glass coat?  HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604  (mm) 0.420-0.350 0.420-0.350 0.420-0.350 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420  24 25 26 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23  4-4-3524 4-4-3525 4-4-3526 4-5-401 4-5-402 4-5-403 4-5-404 4-5-405 4-5-406 4-5-407 4-5-408 4-5-409 4-5-410 4-5-411 4-5-412 4-5-413 4-5-414 4-5-415 4-5-416 4-5-417 4-5-418 4-5-419 4-5-420 4-5-421 4-5-422 4-5-423  plag plag plag plag plag plag plag plag x 2 plag plag plag plag plag plag plag plag plag plag plag plag plag plag plag plag plag plag  yes yes yes yes yes yes yes yes yes yes yes yes yes no yes yes yes yes yes yes yes yes yes yes yes yes  Zoning group D S D S S S S D S D S S D S D S S S D D S S D D D S  H L H&M M M H H L H M L -  91  PC P A P -  EMPA  Trace elements  Isotopes  points points traverse points points -  points points points & traverse points & traverse points points -  -  Table A2 continued. Crystal inventory for samples HW0604 and HW0607. Sample  Size fraction  No.  Name  Type  Glass coat?  HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0604 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607  (mm) 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 1.0-0.595 1.0-0.595 1.0-0.595 1.0-0.595 1.0-0.595 2.0-1.0 2.0-1.0 2.0-1.0 2.0-1.0 2.0-1.0 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350  24 25 26 27 28 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 6 7 8 9 10  4-5-424 4-5-425 4-5-426 4-5-427 4-5-428 4-1-5901 4-1-5902 4-1-5903 4-1-5904 4-1-5905 4-2-101 4-2-102 4-2-103 4-2-104 4-2-105 7-4-3501 7-4-3502 7-4-3503 7-4-3504 7-4-3505 7-4-3506 7-4-3507 7-4-3508 7-4-3509 7-4-3510  plag plag plag plag plag plag plag plag plag plag quartz plag plag plag plag plag plag plag plag plag plag plag plag plag plag  yes no yes yes yes yes yes yes yes yes yes no yes yes yes yes yes yes yes yes yes yes yes yes  Zoning group S S S D D D S D S D D D D D S S D D D S D D S D  H H M H H H H M M L L L L H H  92  CC PC PC A A PC CC SR  EMPA  Trace elements  Isotopes  points points traverse points 2 traverses traverse points points points points points -  points & traverse points points & traverse points & traverse traverse traverse  -  Table A2 continued. Crystal inventory for samples HW0604 and HW0607. Sample HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607  Size fraction (mm) 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.420-0.350 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420  No.  Name  Type  Glass coat?  11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 1 2 3 4  7-4-3511 7-4-3512 7-4-3513 7-4-3514 7-4-3515 7-4-3516 7-4-3517 7-4-3518 7-4-3519 7-4-3520 7-4-3521 7-4-3522 7-4-3523 7-4-3524 7-4-3525 7-4-3526 7-4-3527 7-4-3528 7-4-3529 7-4-3530 7-4-3531 7-4-3532 7-5-401 7-5-402 7-5-403 7-5-404  plag plag plag plag plag plag glass? plag plag plag quartz plag plag glass plag plag plag plag plag glass plag plag glass plag plag plag  yes yes yes no yes yes yes yes yes yes no yes yes yes yes yes yes yes yes yes yes  Zoning group S D D D D D S S D S D S D S D S S D S D S  M L H M H H L M L M H -  93  CC CC CC CC -  EMPA  Trace elements  2 traverses points points traverse traverse points points  points & traverse points points points points points & traverse -  Isotopes -  Table A2 continued. Crystal inventory for samples HW0604 and HW0607.  HW0607 HW0607 HW0607  Size fraction (mm) 0.595-0.420 0.595-0.420 0.595-0.420  HW0607  0.595-0.420  8  7-5-408  HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607 HW0607  0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 0.595-0.420 1.0-0.595 1.0-0.595 1.0-0.595 1.0-0.595 1.0-0.595 2.0-1.0 2.0-1.0  9 10 11 12 13 1 2 3 4 5 1 2  7-5-409 7-5-410 7-5-411 7-5-412 7-5-413 7-1-5901 7-1-5902 7-1-5903 7-1-5904 7-1-5905 7-2-101 7-2-102  HW0607  2.0-1.0  3  7-2-103  HW0607 HW0607  2.0-1.0 2.0-1.0  4 5  7-2-104 7-2-105  Sample  No.  Name  Type  5 6 7  7-5-405 7-5-406 7-5-407  plag plag plag plag + qtz quartz plag plag plag quartz plag plag glass plag plag plag plag plag + qtz plag plag  Glass coat?  Zoning group  EMPA  Trace elements  Isotopes  no yes yes  D D D  H M L  CC -  2 traverses -  points & traverse points -  -  yes  S  -  -  -  -  -  no yes yes yes yes yes yes yes yes  D D D D D S S S D  M H H H H M  SR A CC A -  points points points points traverse traverse points points 2 traverses  points & traverse points & traverse points points points & traverse points & traverse  -  yes  S  -  -  -  -  -  yes yes  S D  L  -  points points  points points  -  94  APPENDIX E: Sample preparation and polishing Machined acrylic pucks of one-inch diameter (probe-mount size) were used so that samples were of standard dimensions for analyses. These pucks were affixed to a glass slide with double-sided tape. Plagioclase crystals were carefully mounted with the double-sided tape such that their c-axes were perpendicular to the slide before pouring BuehlerTM Epoxicure resin (5 parts resin: 1 part hardener). Tiny bubbles were removed immediately using a needle and samples were left to cure overnight at ambient temperature. Once cured, the sample pucks were ground using Buehler carbimet SiC papers (240, 320, 400, and 600 grits) on a Buehler Handimet 2 roll grinder until all crystals were approximately bisected (I used a binocular microscope intermittently to determine the approximate position in the crystal). Then, the pucks were polished with Buehler diamond pastes (6, 3, and 1 µm) on Buehler Minimet 100 automated polisher with Texmet 1000 cloths using MetaDi extender cutting fluid. Next, Buehler MasterPrep 0.05 µm alumina suspension with a Buehler Petro-thin polisher was used to polish the sample pucks for five minutes with 0.75 kg pressure and water as a coolant/lubricant on MasterTex 1000 cloth. For the final polish, the samples were subjected to 30 minutes of vibratory polishing with MasterMet 0.05 µm colloidal silica using a Buehler Vibromet on MasterTex 1000 cloth.  95  APPENDIX F: Electron microprobe analysis data Table A3. Electron micoprobe analysis data Label 4-2-102-1_1 4-2-102-1_2 4-2-102-1_3 4-2-102-1_4 4-2-102-1_5 4-2-102-1_6 4-2-102-1_7 4-2-102-1_8 4-2-102-1_9 4-2-102-1_10 4-2-102-1_11 4-2-102-1_12 4-2-102-1_13 4-2-102-1_14 4-2-102-1_15 4-2-102-1_16 4-2-102-1_17 4-2-102-1_18 4-2-102-1_19 4-2-102-1_20 4-2-102-1_21 4-2-102-1_22 4-2-102-1_23 4-2-102-1_24 4-2-102-1_25 4-2-102-1_26 4-2-102-1_27 4-2-102-1_28 4-2-102-1_29 4-2-102-1_30  SiO2 59.88 59.80 59.69 59.85 59.50 58.72 58.56 58.49 57.60 58.42 57.05 58.04 57.04 58.65 58.56 58.22 57.65 58.83 57.97 57.98 58.05 58.70 58.75 58.67 58.53 59.31 58.98 60.09 58.62 59.53  Al2O3 25.43 25.10 25.21 25.35 25.46 26.23 26.16 26.27 26.42 26.20 26.55 26.56 26.94 25.87 26.11 26.09 26.01 25.84 26.51 26.47 26.50 25.96 25.78 26.18 25.75 25.50 25.71 25.99 25.75 25.53  CaO 7.60 7.51 7.25 7.46 7.39 8.21 8.48 8.59 8.81 8.90 9.18 9.04 8.85 8.68 8.55 8.25 8.30 8.33 8.76 8.73 8.56 8.37 8.22 8.06 7.98 8.02 7.88 7.80 8.28 7.91  Na2O 7.03 6.94 7.15 6.89 6.81 6.28 6.70 6.64 6.30 6.22 6.15 6.10 6.24 6.50 6.55 6.28 6.37 6.63 6.28 6.25 6.25 6.56 6.49 6.59 6.83 6.61 6.66 6.75 6.80 6.72  K2O 0.42 0.34 0.35 0.34 0.44 0.35 0.35 0.41 0.28 0.27 0.28 0.31 0.23 0.28 0.32 0.27 0.31 0.34 0.29 0.32 0.35 0.39 0.39 0.31 0.39 0.39 0.38 0.35 0.37 0.32  MgO 0.01 0.03 0.02 0.05 0.01 0.02 0.01 0.02 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.04 0.04 0.00 0.01 0.02 0.03 0.00 0.00 0.00 0.02 0.00 0.01 0.00 0.01  MnO 0.03 0.00 0.06 0.00 0.05 0.00 0.00 0.02 0.00 0.04 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.01 0.02 0.00 0.01 0.00 0.00 0.05 0.00 0.00 0.00 0.01 0.00  FeO 0.17 0.33 0.27 0.30 0.30 0.31 0.33 0.39 0.25 0.18 0.19 0.18 0.31 0.27 0.31 0.12 0.25 0.15 0.31 0.26 0.24 0.17 0.26 0.29 0.19 0.23 0.18 0.39 0.23 0.19  96  Total 100.56 100.04 100.00 100.24 99.96 100.11 100.58 100.82 99.66 100.23 99.41 100.23 99.61 100.26 100.40 99.23 98.94 100.16 100.12 100.04 99.98 100.20 99.90 100.09 99.72 100.09 99.78 101.38 100.06 100.21  mol frac An 0.365 0.367 0.352 0.367 0.365 0.411 0.403 0.407 0.429 0.435 0.445 0.442 0.434 0.418 0.411 0.414 0.411 0.402 0.428 0.428 0.422 0.404 0.402 0.396 0.384 0.392 0.387 0.382 0.394 0.387  mol frac Ab 0.611 0.613 0.628 0.613 0.609 0.569 0.577 0.570 0.555 0.550 0.539 0.540 0.553 0.566 0.570 0.570 0.571 0.579 0.555 0.554 0.558 0.573 0.575 0.586 0.594 0.585 0.591 0.598 0.585 0.595  mol frac Or 0.024 0.020 0.020 0.020 0.026 0.021 0.020 0.023 0.016 0.016 0.016 0.018 0.013 0.016 0.018 0.016 0.018 0.020 0.017 0.019 0.021 0.022 0.023 0.018 0.022 0.023 0.022 0.020 0.021 0.019  Table A3 continued. Electron microprobe analysis data Label 4-2-102-1_31 4-2-102-1_32 4-2-102-1_33 4-2-102-1_34 4-2-102-1_35 4-2-102-1_36 4-2-102-1_37 4-2-102-1_38 4-2-102-1_39 4-2-102-1_40 4-2-102-1_41 4-2-102-1_42 4-2-102-1_43 4-2-102-1_44 4-2-102-1_45 4-2-102-1_46 4-2-102-1_47 4-2-102-1_48 4-2-102-1_49 4-2-102-1_50 4-2-102-1_51 4-2-102-1_52 4-2-102-1_53 4-2-102-1_54 4-2-102-1_55 4-2-102-1_56 4-2-102-1_57 4-2-102-1_58 4-2-102-1_59 4-2-102-1_60 4-2-102-1_61 4-2-102-1_62 4-2-102-1_63  SiO2 58.50 58.36 58.22 59.00 58.87 59.38 57.87 58.66 58.80 58.93 58.74 58.81 58.31 58.52 58.11 58.95 58.94 58.81 58.62 59.04 58.43 59.15 58.48 58.55 59.30 58.80 58.61 59.81 58.47 59.12 59.20 59.13 58.56  Al2O3 25.63 26.09 25.70 25.75 25.82 26.20 26.08 25.75 25.71 26.20 25.94 25.66 26.08 26.16 25.86 25.79 25.96 25.91 25.85 25.91 26.02 25.94 25.55 25.63 25.57 25.65 25.73 25.69 25.57 26.01 25.52 25.35 25.40  CaO 8.12 8.50 8.12 8.01 7.97 8.21 7.99 8.10 8.12 8.12 8.28 8.20 8.31 8.49 8.48 7.95 7.83 8.22 8.33 8.05 7.94 8.07 7.88 7.87 7.85 7.73 7.97 7.92 7.92 7.97 7.54 7.74 7.80  Na2O 6.97 6.23 6.66 6.85 6.32 6.76 6.66 6.65 6.71 6.56 6.64 6.62 6.75 6.79 6.51 6.31 6.53 6.71 6.36 6.78 6.72 6.73 6.59 6.70 6.84 6.46 6.87 6.85 6.72 6.72 6.63 7.06 6.87  K2O 0.34 0.30 0.39 0.33 0.30 0.34 0.38 0.41 0.32 0.38 0.37 0.32 0.30 0.34 0.22 0.41 0.32 0.40 0.34 0.40 0.30 0.34 0.34 0.37 0.43 0.37 0.38 0.35 0.43 0.32 0.42 0.42 0.34  MgO 0.00 0.02 0.00 0.01 0.03 0.01 0.02 0.03 0.00 0.02 0.02 0.00 0.00 0.02 0.01 0.01 0.00 0.00 0.00 0.00 0.01 0.02 0.01 0.01 0.00 0.02 0.05 0.01 0.02 0.00 0.00 0.02 0.02  MnO 0.00 0.04 0.09 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.04 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.02 0.01 0.00 0.04 0.01  FeO 0.14 0.30 0.20 0.31 0.29 0.12 0.38 0.15 0.29 0.40 0.26 0.40 0.24 0.30 0.30 0.20 0.31 0.43 0.23 0.33 0.28 0.29 0.18 0.39 0.27 0.22 0.33 0.15 0.33 0.33 0.32 0.37 0.30  97  Total 99.69 99.84 99.38 100.26 99.60 101.01 99.36 99.78 99.94 100.62 100.29 100.01 100.00 100.62 99.50 99.64 99.88 100.49 99.74 100.52 99.70 100.54 99.03 99.51 100.26 99.24 99.94 100.79 99.48 100.48 99.63 100.13 99.30  mol frac An 0.384 0.422 0.394 0.385 0.403 0.394 0.390 0.393 0.393 0.397 0.399 0.399 0.398 0.401 0.413 0.400 0.391 0.395 0.412 0.387 0.388 0.391 0.390 0.385 0.379 0.389 0.382 0.382 0.385 0.389 0.376 0.368 0.378  mol frac Ab 0.597 0.560 0.584 0.596 0.579 0.587 0.588 0.584 0.588 0.581 0.580 0.583 0.585 0.580 0.574 0.575 0.590 0.583 0.569 0.590 0.594 0.590 0.590 0.593 0.597 0.589 0.596 0.598 0.591 0.593 0.599 0.608 0.602  mol frac Or 0.019 0.018 0.023 0.019 0.018 0.019 0.022 0.024 0.019 0.022 0.021 0.019 0.017 0.019 0.013 0.025 0.019 0.023 0.020 0.023 0.018 0.020 0.020 0.022 0.025 0.022 0.022 0.020 0.025 0.019 0.025 0.024 0.020  Table A3 continued. Electron microprobe analysis data Label 4-2-102-1_64 4-2-102-1_65 4-2-102-1_66 4-2-102-1_67 4-2-102-1_68 4-2-102-1_69 4-2-102-1_70 4-2-102-1_71 4-2-102-1_72 4-2-102-1_73 4-2-102-1_74 4-2-102-1_75 4-2-102-1_76 4-2-102-1_77 4-2-102-1_78 4-2-102-1_79 4-2-102-1_80 4-2-102-1_81 4-2-102-1_82 4-2-102-1_83 4-2-102-1_84 4-2-102-1_85 4-2-102-1_86 4-2-102-1_87 4-2-102-1_88 4-2-102-1_89 4-2-102-1_90 4-2-102-1_91 4-2-102-1_92 4-2-102-1_93 4-2-102-1_94 4-2-102-1_95 4-2-102-1_96  SiO2 59.54 59.25 59.64 59.80 59.96 60.23 60.43 59.48 60.68 60.31 60.64 60.72 60.96 60.72 61.20 60.48 60.67 60.08 59.89 59.87 60.20 60.58 60.44 58.58 60.33 59.69 60.35 59.93 59.82 59.71 61.05 61.24 61.04  Al2O3 25.58 25.54 25.82 25.27 24.88 24.85 24.72 24.83 24.82 25.43 24.94 24.93 24.45 24.59 24.30 24.50 24.96 25.04 25.05 25.01 25.27 24.88 24.87 26.17 25.58 25.23 25.23 25.01 25.02 24.59 24.85 24.52 24.64  CaO 7.67 7.58 7.72 7.39 7.00 7.19 6.81 7.11 6.77 6.88 6.83 6.99 6.73 6.44 6.51 6.55 6.95 7.18 7.61 7.05 7.05 6.84 7.14 8.13 7.10 7.11 7.59 7.06 7.11 6.84 6.80 6.50 6.16  Na2O 6.91 6.77 6.99 6.86 6.92 7.11 7.14 7.12 7.46 7.16 7.12 7.34 7.00 7.16 7.30 7.43 7.24 6.94 6.84 6.83 7.24 7.19 7.11 6.81 6.75 7.27 6.78 6.97 7.05 7.20 7.27 7.45 7.18  K2O 0.35 0.40 0.35 0.46 0.49 0.51 0.43 0.43 0.39 0.49 0.48 0.43 0.49 0.46 0.42 0.50 0.40 0.45 0.42 0.42 0.44 0.46 0.38 0.39 0.42 0.37 0.37 0.44 0.39 0.46 0.55 0.51 0.55  MgO 0.03 0.01 0.04 0.00 0.00 0.01 0.03 0.04 0.01 0.04 0.01 0.00 0.02 0.00 0.02 0.01 0.00 0.02 0.00 0.00 0.00 0.00 0.01 0.00 0.01 0.03 0.01 0.03 0.02 0.02 0.03 0.01 0.00  MnO 0.01 0.07 0.01 0.00 0.04 0.00 0.00 0.02 0.00 0.00 0.05 0.00 0.00 0.01 0.01 0.07 0.06 0.00 0.00 0.00 0.00 0.00 0.03 0.00 0.02 0.02 0.00 0.03 0.00 0.00 0.00 0.00 0.00  FeO 0.17 0.14 0.20 0.32 0.29 0.17 0.32 0.25 0.19 0.30 0.29 0.16 0.22 0.24 0.31 0.28 0.29 0.19 0.17 0.33 0.23 0.33 0.08 0.27 0.27 0.26 0.22 0.23 0.28 0.13 0.27 0.15 0.22  98  Total 100.25 99.77 100.78 100.10 99.59 100.07 99.87 99.28 100.32 100.61 100.36 100.58 99.86 99.62 100.06 99.82 100.55 99.90 99.97 99.51 100.44 100.29 100.05 100.34 100.47 99.96 100.54 99.70 99.70 98.93 100.82 100.38 99.79  mol frac An 0.373 0.373 0.371 0.363 0.348 0.348 0.336 0.347 0.327 0.337 0.337 0.336 0.337 0.323 0.322 0.318 0.339 0.354 0.371 0.354 0.341 0.335 0.349 0.389 0.358 0.343 0.374 0.350 0.350 0.335 0.330 0.316 0.311  mol frac Ab 0.607 0.603 0.609 0.610 0.623 0.623 0.638 0.628 0.651 0.635 0.635 0.639 0.634 0.650 0.653 0.653 0.638 0.619 0.604 0.621 0.634 0.638 0.629 0.589 0.616 0.635 0.604 0.625 0.628 0.638 0.638 0.655 0.656  mol frac Or 0.020 0.024 0.020 0.027 0.029 0.029 0.025 0.025 0.022 0.029 0.028 0.025 0.029 0.028 0.025 0.029 0.023 0.026 0.024 0.025 0.025 0.027 0.022 0.022 0.025 0.021 0.022 0.026 0.023 0.027 0.032 0.030 0.033  Table A3 continued. Electron microprobe analysis data Label 4-2-102-1_97 4-2-102-1_98 4-2-102-1_99 4-2-102-1_100  SiO2 61.27 77.25 75.33 75.35  Al2O3 24.59 12.40 12.60 12.72  CaO 6.50 1.05 1.02 1.12  Na2O 7.32 3.51 2.46 3.67  K2O 0.47 3.64 3.95 3.86  MgO 0.01 0.12 0.17 0.17  MnO 0.00 0.07 0.06 0.12  FeO 0.33 1.36 1.24 1.31  Total 100.47 99.40 96.84 98.33  mol frac An 0.320 0.090 0.100 0.091  mol frac Ab 0.652 0.541 0.438 0.537  mol frac Or 0.028 0.369 0.462 0.372  4-2-103-1 4-2-103-2  59.97 62.84  25.32 23.15  7.19 4.31  7.12 8.30  0.35 0.56  0.01 0.00  0.00 0.02  0.17 0.09  100.12 99.27  0.351 0.216  0.629 0.751  0.020 0.033  4-2-104-1 4-2-104-2  60.65 62.19  24.57 23.94  6.54 5.72  7.24 7.71  0.50 0.57  0.02 0.02  0.00 0.00  0.20 0.11  99.73 100.26  0.323 0.281  0.647 0.686  0.029 0.033  4-2-105-1 4-2-105-2  61.70 61.58  23.33 24.37  5.41 6.14  7.80 7.67  0.66 0.52  0.00 0.00  0.00 0.02  0.14 0.18  99.05 100.49  0.266 0.298  0.695 0.673  0.039 0.030  4-1-5901-1 4-1-5901-2  61.77 60.75  24.03 25.19  5.72 7.03  7.56 7.17  0.58 0.44  0.01 0.00  0.02 0.02  0.23 0.29  99.93 100.88  0.285 0.342  0.681 0.632  0.034 0.026  4-1-5902-1 4-1-5902-2  63.80 61.94  22.75 24.06  4.33 5.88  8.31 7.92  0.66 0.43  0.00 0.00  0.01 0.00  0.10 0.31  99.95 100.55  0.215 0.284  0.746 0.692  0.039 0.025  4-1-5903_1 4-1-5903_2 4-1-5903_3 4-1-5903_4 4-1-5903_5 4-1-5903_6 4-1-5903_7 4-1-5903_8 4-1-5903_9 4-1-5903_10 4-1-5903_11 4-1-5903_12 4-1-5903_13  62.67 62.39 61.61 62.01 59.81 60.46 59.61 59.58 59.96 59.91 58.74 59.84 59.19  23.69 23.68 23.75 23.69 24.94 24.78 25.25 25.13 25.53 25.38 24.97 25.48 25.69  5.73 5.51 5.37 5.78 7.10 7.29 7.31 7.53 7.79 7.49 7.65 7.75 7.73  7.63 7.81 7.59 7.72 7.19 6.88 6.98 7.06 6.92 6.96 6.70 6.62 6.97  0.54 0.62 0.57 0.61 0.48 0.40 0.44 0.46 0.42 0.41 0.40 0.45 0.40  0.00 0.01 0.01 0.00 0.00 0.02 0.02 0.01 0.00 0.00 0.02 0.01 0.02  0.00 0.09 0.02 0.02 0.09 0.00 0.02 0.00 0.00 0.04 0.02 0.09 0.00  0.17 0.14 0.13 0.20 0.21 0.20 0.17 0.18 0.15 0.09 0.15 0.32 0.27  100.43 100.23 99.04 100.04 99.81 100.03 99.80 99.95 100.79 100.27 98.66 100.56 100.28  0.284 0.270 0.271 0.282 0.343 0.361 0.357 0.361 0.374 0.364 0.378 0.382 0.371  0.684 0.693 0.694 0.682 0.629 0.616 0.617 0.613 0.602 0.612 0.599 0.591 0.606  0.032 0.036 0.034 0.036 0.028 0.024 0.026 0.026 0.024 0.024 0.024 0.026 0.023  99  Table A3 continued. Electron microprobe analysis data Label 4-1-5903_14 4-1-5903_15 4-1-5903_16 4-1-5903_17 4-1-5903_18 4-1-5903_19 4-1-5903_20 4-1-5903_21 4-1-5903_22 4-1-5903_23 4-1-5903_24 4-1-5903_25 4-1-5903_26 4-1-5903_27 4-1-5903_28 4-1-5903_29 4-1-5903_30 4-1-5903_31 4-1-5903_32 4-1-5903_33 4-1-5903_34 4-1-5903_35 4-1-5903_36 4-1-5903_37 4-1-5903_38 4-1-5903_39 4-1-5903_40 4-1-5903_41 4-1-5903_42 4-1-5903_43 4-1-5903_44 4-1-5903_45 4-1-5903_46  SiO2 60.30 58.97 60.27 58.16 58.75 59.11 59.91 57.81 57.14 59.25 59.30 59.19 58.39 58.40 57.65 58.80 58.90 58.95 57.72 58.67 58.22 58.42 59.03 59.73 58.51 58.82 59.28 58.47 58.47 58.69 59.02 59.22  Al2O3 25.34 25.21 25.04 26.41 26.15 25.30 25.10 26.28 26.93 26.20 25.89 25.58 25.70 25.88 26.31 26.33 25.95 26.23 25.90 26.38 26.19 26.04 25.61 25.68 25.73 25.72 25.72 25.68 25.82 26.02 25.97 25.74  CaO 7.68 7.70 7.14 8.93 8.81 7.81 7.37 8.84 9.46 8.80 8.06 8.16 8.11 8.31 9.07 8.66 8.69 8.04 8.71 8.37 8.56 8.32 8.27 7.82 8.07 8.16 8.21 8.21 8.45 8.46 8.05 8.16  Na2O 7.01 6.73 6.78 6.38 6.49 6.53 6.59 5.89 6.21 6.15 6.55 6.39 6.27 6.41 6.17 6.24 6.47 6.61 6.49 6.66 6.67 6.33 6.50 6.73 6.43 6.68 6.62 6.60 6.21 6.49 6.52 6.73  K2O 0.41 0.38 0.38 0.37 0.34 0.34 0.46 0.36 0.25 0.33 0.36 0.45 0.30 0.29 0.24 0.26 0.39 0.35 0.36 0.42 0.32 0.37 0.29 0.25 0.31 0.31 0.34 0.33 0.36 0.34 0.38 0.33  MgO 0.03 0.00 0.01 0.00 0.02 0.02 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.01 0.00 0.00 0.01 0.05 0.00 0.04 0.01 0.02 0.02 0.00 0.00 0.00 0.00 0.02 0.03  MnO 0.00 0.00 0.01 0.03 0.05 0.07 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.05 0.01 0.00 0.00 0.03 0.01 0.00 0.03 0.00 0.00 0.02 0.03 0.07 0.00 0.00 0.00 0.00 0.00 0.01  FeO 0.24 0.27 0.17 0.22 0.28 0.13 0.15 0.25 0.25 0.30 0.33 0.12 0.20 0.19 0.37 0.19 0.14 0.11 0.22 0.33 0.18 0.34 0.27 0.29 0.24 0.20 0.26 0.24 0.23 0.31 0.24 0.18  100  Total 101.01 99.27 99.80 100.49 100.88 99.30 99.58 99.42 100.26 101.04 100.50 99.89 98.96 99.53 99.82 100.50 100.55 100.31 99.42 100.85 100.22 99.81 100.01 100.51 99.33 99.97 100.43 99.54 99.54 100.31 100.20 100.40  mol frac An 0.368 0.379 0.360 0.427 0.420 0.390 0.371 0.444 0.451 0.433 0.396 0.403 0.409 0.410 0.442 0.427 0.417 0.394 0.417 0.400 0.407 0.412 0.406 0.385 0.402 0.396 0.399 0.400 0.420 0.411 0.397 0.394  mol frac Ab 0.608 0.599 0.618 0.552 0.560 0.590 0.601 0.535 0.535 0.548 0.583 0.571 0.573 0.573 0.544 0.557 0.561 0.586 0.562 0.576 0.575 0.567 0.577 0.600 0.580 0.586 0.582 0.581 0.559 0.570 0.581 0.587  mol frac Or 0.023 0.022 0.023 0.021 0.019 0.020 0.028 0.022 0.014 0.019 0.021 0.026 0.018 0.017 0.014 0.015 0.022 0.020 0.021 0.024 0.018 0.022 0.017 0.015 0.018 0.018 0.020 0.019 0.021 0.020 0.022 0.019  Table A3 continued. Electron microprobe analysis data Label 4-1-5903_47 4-1-5903_48 4-1-5903_49 4-1-5903_50 4-1-5903_51 4-1-5903_52 4-1-5903_53 4-1-5903_54 4-1-5903_55 4-1-5903_56 4-1-5903_57 4-1-5903_58 4-1-5903_59 4-1-5903_60 4-1-5903_61 4-1-5903_62 4-1-5903_63 4-1-5903_64 4-1-5903_65 4-1-5903_66 4-1-5903_67 4-1-5903_68 4-1-5903_69 4-1-5903_70  SiO2 58.57 59.00 58.46 58.70 57.73 59.42 59.24 59.32 59.46 59.48 59.40 59.50 59.47 60.08 60.04 60.64 60.02 60.30 60.25 60.21 59.68 60.01 59.74 60.41  Al2O3 25.60 26.32 25.79 25.99 25.95 25.95 25.47 25.69 25.66 25.70 25.63 25.36 25.16 25.24 25.01 24.87 25.18 25.00 25.00 25.30 25.17 25.09 25.04 24.93  CaO 8.27 8.73 8.47 8.37 8.15 8.09 7.80 7.92 7.83 7.62 7.71 7.89 7.47 7.53 7.37 7.18 7.32 7.42 7.23 7.45 7.71 7.45 7.61 7.41  Na2O 6.54 6.37 6.62 6.53 6.34 6.73 6.93 6.75 6.60 6.70 6.75 6.86 6.70 7.06 7.13 7.11 7.15 6.58 7.15 7.00 6.81 7.02 7.08 7.00  K2O 0.33 0.33 0.31 0.34 0.39 0.39 0.31 0.32 0.28 0.38 0.38 0.39 0.35 0.42 0.36 0.43 0.44 0.39 0.46 0.43 0.38 0.45 0.35 0.42  MgO 0.04 0.02 0.01 0.02 0.04 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.00 0.02 0.03 0.01 0.00 0.03 0.03 0.01  MnO 0.00 0.02 0.03 0.01 0.00 0.03 0.00 0.03 0.00 0.00 0.00 0.05 0.01 0.00 0.04 0.00 0.02 0.00 0.00 0.00 0.00 0.01 0.10 0.01  FeO 0.27 0.30 0.27 0.31 0.25 0.16 0.30 0.28 0.29 0.24 0.37 0.33 0.18 0.21 0.31 0.30 0.23 0.33 0.21 0.20 0.23 0.22 0.38 0.33  Total 99.62 101.09 99.95 100.27 98.85 100.80 100.05 100.31 100.12 100.13 100.25 100.38 99.33 100.57 100.26 100.53 100.36 100.04 100.35 100.60 99.99 100.29 100.32 100.52  mol frac An 0.404 0.423 0.407 0.407 0.406 0.390 0.377 0.386 0.389 0.377 0.378 0.380 0.373 0.362 0.356 0.349 0.352 0.375 0.349 0.361 0.376 0.360 0.365 0.360  mol frac Ab 0.577 0.558 0.575 0.574 0.571 0.587 0.606 0.595 0.594 0.600 0.599 0.598 0.606 0.614 0.623 0.626 0.623 0.602 0.625 0.614 0.602 0.614 0.615 0.616  mol frac Or 0.019 0.019 0.018 0.020 0.023 0.022 0.018 0.019 0.017 0.022 0.022 0.022 0.021 0.024 0.021 0.025 0.025 0.024 0.026 0.025 0.022 0.026 0.020 0.024  4-1-5904-1 4-1-5904-2  61.71 62.59  23.97 23.65  5.90 5.48  7.68 8.17  0.43 0.42  0.00 0.03  0.00 0.00  0.08 0.13  99.77 100.46  0.291 0.264  0.684 0.712  0.025 0.024  4-1-5905-1_1 4-1-5905-1_2 4-1-5905-1_3 4-1-5905-1_4 4-1-5905-1_5  57.47 57.89 57.88 58.09 58.24  26.37 26.27 26.41 26.13 25.84  9.06 9.07 8.93 8.88 8.78  6.35 6.06 5.88 5.94 6.59  0.34 0.27 0.32 0.36 0.25  0.04 0.05 0.02 0.00 0.00  0.00 0.03 0.00 0.00 0.05  0.43 0.35 0.27 0.38 0.36  100.06 99.99 99.70 99.78 100.11  0.432 0.446 0.448 0.443 0.418  0.548 0.539 0.533 0.536 0.568  0.019 0.016 0.019 0.021 0.014  101  Table A3 continued. Electron microprobe analysis data Label 4-1-5905-1_6 4-1-5905-1_7 4-1-5905-1_8 4-1-5905-1_9 4-1-5905-1_10 4-1-5905-1_11 4-1-5905-1_12 4-1-5905-1_13 4-1-5905-1_14 4-1-5905-1_15 4-1-5905-1_16 4-1-5905-1_17 4-1-5905-1_18 4-1-5905-1_19 4-1-5905-1_20 4-1-5905-1_21 4-1-5905-1_22 4-1-5905-1_23 4-1-5905-1_24 4-1-5905-1_25 4-1-5905-1_26 4-1-5905-1_27 4-1-5905-1_28 4-1-5905-1_29 4-1-5905-1_30 4-1-5905-1_31 4-1-5905-1_32 4-1-5905-1_33 4-1-5905-1_34 4-1-5905-1_35 4-1-5905-1_36 4-1-5905-1_37 4-1-5905-1_38  SiO2 57.53 57.42 57.77 57.90 57.23 57.85 58.25 58.40 58.45 57.12 56.64 57.21 56.80 57.36 56.52 57.54 57.47 58.07 57.58 57.63 55.93 57.05 56.17 55.96 56.33 56.42 56.12 57.22 56.35 57.58 57.52 58.57  Al2O3 26.14 26.42 26.52 26.49 26.67 26.39 26.26 26.45 26.11 26.87 27.32 26.91 26.80 26.89 26.99 26.55 26.69 26.46 26.59 26.94 27.80 27.28 27.54 27.21 27.06 27.10 27.20 26.84 27.37 27.08 26.35 26.37  CaO 8.84 9.01 9.17 8.91 8.80 8.96 8.89 8.88 8.85 9.66 9.78 9.39 9.27 9.50 9.25 9.23 8.95 8.99 8.78 9.46 10.12 9.70 10.02 10.06 9.95 9.85 9.78 9.66 9.95 9.77 8.72 8.89  Na2O 5.97 6.05 6.20 6.24 6.17 6.43 6.15 6.19 6.50 6.17 5.92 6.06 5.88 5.92 5.99 6.15 6.19 6.10 6.00 5.79 5.50 5.63 5.83 5.83 5.56 5.98 5.80 5.81 5.71 5.82 6.21 6.05  K2O 0.29 0.33 0.35 0.27 0.28 0.25 0.30 0.31 0.34 0.30 0.30 0.27 0.28 0.29 0.30 0.25 0.23 0.35 0.24 0.30 0.21 0.24 0.28 0.25 0.22 0.28 0.32 0.31 0.22 0.29 0.30 0.27  MgO 0.00 0.03 0.02 0.04 0.02 0.00 0.01 0.00 0.02 0.03 0.04 0.03 0.02 0.00 0.00 0.01 0.00 0.00 0.00 0.02 0.00 0.05 0.00 0.03 0.00 0.00 0.01 0.02 0.01 0.00 0.03 0.00  MnO 0.04 0.09 0.00 0.02 0.00 0.00 0.01 0.00 0.04 0.03 0.00 0.04 0.05 0.03 0.00 0.05 0.03 0.01 0.07 0.07 0.00 0.02 0.09 0.00 0.01 0.00 0.04 0.04 0.02 0.00 0.00 0.00  102  FeO 0.34 0.20 0.34 0.30 0.36 0.30 0.35 0.27 0.28 0.29 0.19 0.29 0.26 0.23 0.33 0.33 0.45 0.34 0.29 0.26 0.34 0.27 0.31 0.20 0.26 0.27 0.35 0.22 0.34 0.32 0.28 0.22  Total 99.14 99.55 100.37 100.16 99.52 100.17 100.22 100.49 100.58 100.46 100.19 100.19 99.34 100.22 99.37 100.12 100.00 100.32 99.56 100.46 99.91 100.24 100.22 99.55 99.39 99.91 99.61 100.13 99.97 100.86 99.41 100.36  mol frac An 0.442 0.443 0.441 0.434 0.434 0.429 0.436 0.434 0.421 0.456 0.469 0.454 0.458 0.462 0.452 0.447 0.438 0.440 0.441 0.466 0.498 0.481 0.479 0.481 0.491 0.469 0.474 0.470 0.484 0.473 0.429 0.441  mol frac Ab 0.541 0.538 0.539 0.550 0.550 0.557 0.546 0.548 0.560 0.527 0.514 0.530 0.526 0.521 0.530 0.539 0.548 0.540 0.545 0.516 0.490 0.505 0.505 0.505 0.496 0.515 0.508 0.512 0.503 0.510 0.553 0.543  mol frac Or 0.017 0.019 0.020 0.016 0.016 0.014 0.018 0.018 0.019 0.017 0.017 0.016 0.017 0.017 0.018 0.014 0.013 0.020 0.014 0.018 0.012 0.014 0.016 0.014 0.013 0.016 0.018 0.018 0.013 0.017 0.018 0.016  Table A3 continued. Electron microprobe analysis data Label 4-1-5905-1_39 4-1-5905-1_40  SiO2 58.29 59.05  Al2O3 25.98 25.45  CaO 8.48 8.27  Na2O 6.29 6.39  K2O 0.34 0.36  MgO 0.02 0.00  MnO 0.00 0.00  FeO 0.30 0.31  Total 99.69 99.83  mol frac An 0.418 0.408  mol frac Ab 0.562 0.571  mol frac Or 0.020 0.021  4-1-5905-2_1 4-1-5905-2_2 4-1-5905-2_3 4-1-5905-2_4 4-1-5905-2_5 4-1-5905-2_6 4-1-5905-2_7 4-1-5905-2_8 4-1-5905-2_9 4-1-5905-2_10 4-1-5905-2_11 4-1-5905-2_12 4-1-5905-2_13 4-1-5905-2_14 4-1-5905-2_15 4-1-5905-2_16 4-1-5905-2_17 4-1-5905-2_18 4-1-5905-2_19 4-1-5905-2_20 4-1-5905-2_21 4-1-5905-2_22 4-1-5905-2_23 4-1-5905-2_24 4-1-5905-2_25 4-1-5905-2_26 4-1-5905-2_27 4-1-5905-2_28 4-1-5905-2_29 4-1-5905-2_30  57.70 58.19 57.78 57.99 57.43 58.56 57.87 57.73 56.91 58.01 57.38 58.52 57.95 57.60 57.10 58.65 57.81 58.24 56.05 56.64 56.75 57.21 57.46 57.76 57.63 57.18 57.52 57.33 57.18 57.77  26.26 26.23 26.24 26.12 25.91 26.52 26.52 26.08 26.05 26.07 26.43 26.22 26.41 26.28 26.33 26.06 26.10 26.37 27.13 26.83 26.64 27.02 26.77 26.48 26.58 26.50 26.74 26.65 27.09 26.76  9.09 8.93 8.91 8.76 9.02 8.82 9.14 8.96 8.98 8.89 9.16 8.87 9.20 9.10 9.07 8.88 9.10 8.96 10.05 9.90 9.64 9.53 9.31 9.26 9.26 9.25 9.22 9.19 9.77 9.09  6.16 6.06 6.41 6.04 6.28 6.23 6.12 6.12 6.20 6.27 6.24 5.94 6.25 6.08 5.98 6.01 5.98 6.00 5.63 5.57 5.88 5.76 5.97 6.04 5.78 6.00 6.12 5.85 5.65 6.06  0.27 0.34 0.32 0.32 0.32 0.29 0.31 0.37 0.36 0.28 0.35 0.30 0.30 0.30 0.28 0.31 0.27 0.29 0.25 0.29 0.22 0.28 0.30 0.28 0.27 0.28 0.28 0.22 0.34 0.27  0.01 0.00 0.01 0.00 0.04 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.02 0.00 0.02 0.00 0.00 0.00 0.00 0.01 0.03 0.03 0.00 0.02 0.00 0.00 0.00 0.00  0.00 0.04 0.02 0.05 0.01 0.07 0.00 0.00 0.02 0.05 0.00 0.00 0.01 0.00 0.00 0.02 0.04 0.00 0.05 0.00 0.00 0.00 0.04 0.00 0.02 0.01 0.02 0.00 0.00 0.00  0.18 0.26 0.42 0.35 0.40 0.38 0.20 0.30 0.34 0.29 0.18 0.29 0.17 0.27 0.28 0.19 0.27 0.33 0.22 0.34 0.34 0.29 0.24 0.26 0.21 0.33 0.37 0.31 0.23 0.14  99.68 100.05 100.10 99.63 99.42 100.87 100.15 99.56 98.86 99.86 99.74 100.15 100.28 99.62 99.07 100.10 99.58 100.20 99.39 99.56 99.47 100.10 100.11 100.11 99.76 99.57 100.28 99.55 100.25 100.09  0.442 0.440 0.427 0.436 0.434 0.432 0.444 0.438 0.435 0.432 0.439 0.444 0.441 0.445 0.449 0.441 0.450 0.444 0.489 0.487 0.469 0.470 0.455 0.451 0.462 0.453 0.447 0.459 0.479 0.446  0.542 0.540 0.555 0.545 0.547 0.552 0.538 0.541 0.544 0.552 0.541 0.538 0.542 0.538 0.535 0.540 0.535 0.539 0.496 0.496 0.518 0.514 0.528 0.533 0.522 0.531 0.537 0.528 0.501 0.538  0.016 0.020 0.018 0.019 0.018 0.017 0.018 0.022 0.021 0.016 0.020 0.018 0.017 0.018 0.017 0.018 0.016 0.017 0.015 0.017 0.013 0.016 0.017 0.016 0.016 0.016 0.016 0.013 0.020 0.016  103  Table A3 continued. Electron microprobe analysis data Label 4-1-5905-2_31 4-1-5905-2_32 4-1-5905-2_33 4-1-5905-2_34 4-1-5905-2_35 4-1-5905-2_36 4-1-5905-2_37 4-1-5905-2_38 4-1-5905-2_39 4-1-5905-2_40 4-1-5905-2_41 4-1-5905-2_42 4-1-5905-2_43 4-1-5905-2_44 4-1-5905-2_45 4-1-5905-2_46 4-1-5905-2_47 4-1-5905-2_48 4-1-5905-2_49 4-1-5905-2_50 4-1-5905-2_51 4-1-5905-2_52 4-1-5905-2_53 4-1-5905-2_54 4-1-5905-2_55 4-1-5905-2_56 4-1-5905-2_57 4-1-5905-2_58 4-1-5905-2_59 4-1-5905-2_60 4-1-5905-2_61 4-1-5905-2_62 4-1-5905-2_63  SiO2 57.27 58.11 57.11 58.48 58.78 57.70 55.66 56.88 55.69 56.57 56.66 57.33 57.09 57.52 56.62 57.67 57.22 57.21 57.31 58.00 58.65 57.88 58.14 58.34 57.34 57.98 58.01 58.04 58.09 58.37 58.35 58.77 58.28  Al2O3 26.44 26.31 26.22 26.21 26.12 26.49 27.26 26.90 27.29 26.90 27.30 26.61 26.89 26.88 26.72 26.75 26.81 26.71 26.63 26.34 26.47 26.20 26.69 26.46 25.96 26.19 26.36 25.87 25.56 25.94 25.75 25.69 25.59  CaO 9.21 8.80 8.88 8.81 8.46 9.25 10.55 9.71 10.08 9.89 9.87 9.38 9.51 10.42 9.59 9.54 9.80 9.43 9.62 8.95 8.77 8.62 9.12 8.83 8.45 8.72 8.90 8.86 8.70 8.53 8.32 8.11 8.40  Na2O 5.94 6.22 6.09 6.00 6.34 6.40 5.51 5.76 5.46 5.67 5.66 6.01 5.93 5.72 5.70 5.78 5.96 6.04 5.81 6.04 6.40 6.24 6.19 6.24 6.14 6.10 6.28 6.24 6.41 6.16 6.37 6.35 6.54  K2O 0.31 0.36 0.33 0.27 0.32 0.31 0.24 0.26 0.32 0.26 0.24 0.32 0.20 0.29 0.32 0.26 0.28 0.26 0.26 0.32 0.30 0.54 0.30 0.31 0.42 0.33 0.40 0.29 0.30 0.28 0.45 0.37 0.34  MgO 0.04 0.00 0.02 0.04 0.02 0.01 0.00 0.04 0.03 0.02 0.00 0.00 0.02 0.01 0.01 0.05 0.00 0.00 0.01 0.00 0.03 0.27 0.03 0.04 0.32 0.00 0.00 0.00 0.00 0.03 0.04 0.00 0.03  MnO 0.05 0.05 0.03 0.01 0.00 0.04 0.00 0.02 0.00 0.01 0.03 0.00 0.03 0.01 0.03 0.01 0.00 0.00 0.05 0.00 0.00 0.05 0.00 0.06 0.08 0.03 0.00 0.10 0.00 0.00 0.00 0.00 0.00  104  FeO 0.30 0.29 0.28 0.31 0.36 0.29 0.36 0.35 0.45 0.38 0.34 0.41 0.37 0.34 0.28 0.36 0.40 0.25 0.31 0.19 0.15 0.73 0.29 0.31 0.64 0.41 0.41 0.36 0.40 0.32 0.38 0.16 0.40  Total 99.56 100.15 98.96 100.12 100.41 100.48 99.58 99.91 99.32 99.70 100.10 100.06 100.05 101.19 99.27 100.42 100.47 99.91 100.02 99.86 100.77 100.52 100.76 100.57 99.34 99.75 100.34 99.76 99.46 99.64 99.66 99.45 99.58  mol frac An 0.453 0.430 0.438 0.441 0.417 0.436 0.507 0.475 0.496 0.483 0.484 0.455 0.464 0.494 0.473 0.470 0.469 0.456 0.471 0.442 0.424 0.419 0.441 0.431 0.421 0.433 0.429 0.432 0.421 0.426 0.408 0.405 0.407  mol frac Ab 0.529 0.550 0.543 0.543 0.565 0.546 0.479 0.510 0.486 0.502 0.502 0.527 0.524 0.490 0.509 0.515 0.516 0.529 0.514 0.540 0.559 0.549 0.542 0.551 0.554 0.548 0.548 0.551 0.562 0.557 0.566 0.573 0.573  mol frac Or 0.018 0.021 0.019 0.016 0.019 0.017 0.014 0.015 0.019 0.015 0.014 0.019 0.012 0.016 0.019 0.015 0.016 0.015 0.015 0.019 0.017 0.031 0.017 0.018 0.025 0.020 0.023 0.017 0.017 0.017 0.026 0.022 0.020  Table A3 continued. Electron microprobe analysis data Label 4-1-5905-2_64 4-1-5905-2_65 4-1-5905-2_66 4-1-5905-2_67 4-1-5905-2_68 4-1-5905-2_69 4-1-5905-2_70 4-1-5905-2_71 4-1-5905-2_72 4-1-5905-2_73 4-1-5905-2_74 4-1-5905-2_75 4-1-5905-2_76 4-1-5905-2_77 4-1-5905-2_78 4-1-5905-2_79 4-1-5905-2_80 4-1-5905-2_81 4-1-5905-2_82 4-1-5905-2_83 4-1-5905-2_84 4-1-5905-2_85 4-1-5905-2_86 4-1-5905-2_87 4-1-5905-2_88 4-1-5905-2_89 4-1-5905-2_90 4-1-5905-2_91 4-1-5905-2_92 4-1-5905-2_93 4-1-5905-2_94 4-1-5905-2_95 4-1-5905-2_96  SiO2 59.40 58.75 59.29 60.00 60.17 59.07 59.93 59.37 60.33 60.17 61.10 60.00 60.98 60.95 61.43 59.31 60.21 60.97 60.65 61.52 60.54 60.13 61.10 60.86 61.22 63.06 62.86 63.44 63.12 63.09 64.31 62.69 63.15  Al2O3 25.55 25.73 25.14 25.21 25.15 25.02 25.22 25.46 24.93 24.74 24.67 24.51 24.67 24.47 24.50 25.00 24.99 24.70 24.21 24.19 24.40 24.54 24.55 24.31 23.92 22.73 23.26 23.10 23.32 22.90 22.38 23.20 23.20  CaO 7.84 8.05 8.17 7.60 7.60 7.71 7.57 7.83 7.24 6.71 6.92 7.17 6.91 6.66 6.80 7.19 7.61 7.09 6.32 6.54 6.92 6.78 6.78 6.47 6.01 5.13 5.09 4.95 5.01 4.83 4.56 5.10 5.22  Na2O 6.59 6.65 6.62 6.76 6.75 6.68 6.86 6.84 7.09 6.90 7.24 7.20 7.23 7.03 7.31 7.03 7.04 7.45 7.27 7.68 7.10 7.00 7.14 7.40 7.38 7.95 7.93 8.06 7.98 8.31 8.19 7.71 7.98  K2O 0.38 0.28 0.33 0.40 0.43 0.38 0.37 0.44 0.36 0.55 0.42 0.42 0.43 0.37 0.45 0.38 0.38 0.48 0.48 0.48 0.44 0.49 0.47 0.53 0.52 0.61 0.68 0.70 0.67 0.66 0.71 0.73 0.70  MgO 0.01 0.00 0.00 0.01 0.01 0.04 0.02 0.00 0.02 0.01 0.00 0.00 0.04 0.00 0.02 0.00 0.02 0.04 0.01 0.02 0.03 0.00 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00  MnO 0.04 0.00 0.00 0.01 0.00 0.00 0.07 0.00 0.02 0.05 0.00 0.00 0.02 0.01 0.00 0.00 0.03 0.12 0.00 0.00 0.00 0.00 0.02 0.01 0.00 0.00 0.00 0.06 0.05 0.00 0.02 0.00 0.07  FeO 0.35 0.27 0.21 0.30 0.30 0.18 0.25 0.41 0.26 0.31 0.32 0.28 0.19 0.20 0.13 0.17 0.24 0.14 0.29 0.22 0.24 0.16 0.11 0.14 0.19 0.29 0.22 0.23 0.15 0.15 0.09 0.14 0.18  105  Total 100.18 99.72 99.76 100.29 100.41 99.07 100.29 100.35 100.26 99.43 100.67 99.58 100.47 99.70 100.64 99.09 100.53 100.98 99.24 100.65 99.67 99.10 100.20 99.73 99.24 99.77 100.05 100.54 100.30 99.94 100.25 99.56 100.50  mol frac An 0.388 0.394 0.398 0.374 0.374 0.381 0.371 0.378 0.353 0.338 0.337 0.346 0.337 0.336 0.331 0.353 0.366 0.335 0.315 0.311 0.341 0.339 0.335 0.316 0.301 0.253 0.251 0.243 0.247 0.234 0.226 0.256 0.255  mol frac Ab 0.590 0.589 0.583 0.602 0.601 0.597 0.608 0.597 0.626 0.629 0.638 0.630 0.638 0.642 0.643 0.625 0.612 0.638 0.656 0.662 0.633 0.632 0.638 0.654 0.668 0.711 0.709 0.716 0.713 0.728 0.733 0.700 0.705  mol frac Or 0.022 0.016 0.019 0.024 0.025 0.022 0.022 0.025 0.021 0.033 0.024 0.024 0.025 0.022 0.026 0.022 0.022 0.027 0.029 0.027 0.026 0.029 0.028 0.031 0.031 0.036 0.040 0.041 0.039 0.038 0.042 0.044 0.041  Table A3 continued. Electron microprobe analysis data Label 4-1-5905-2_97 4-1-5905-2_98 4-1-5905-2_99 4-1-5905-2_100  SiO2 63.50 64.02 62.10 61.27  Al2O3 22.55 22.46 23.75 24.22  CaO 4.58 4.58 5.60 5.91  Na2O 7.98 8.10 7.91 7.62  K2O 0.80 0.82 0.56 0.52  MgO 0.00 0.00 0.00 0.00  MnO 0.00 0.00 0.05 0.00  FeO 0.10 0.06 0.23 0.19  Total 99.51 100.03 100.19 99.73  mol frac An 0.229 0.227 0.272 0.291  mol frac Ab 0.723 0.725 0.696 0.679  mol frac Or 0.048 0.048 0.032 0.031  4-5-405-1 4-5-405-2  63.06 60.80  23.10 24.71  5.16 7.11  8.02 7.13  0.66 0.44  0.00 0.00  0.02 0.01  0.14 0.19  100.15 100.39  0.252 0.346  0.709 0.628  0.038 0.026  4-5-408-1 4-5-408-2  63.06 64.52  23.02 22.61  4.69 4.09  8.37 8.44  0.65 0.70  0.00 0.00  0.04 0.00  0.22 0.10  100.05 100.45  0.228 0.203  0.735 0.756  0.038 0.041  4-5-410_1 4-5-410_2 4-5-410_3 4-5-410_4 4-5-410_5 4-5-410_6 4-5-410_7 4-5-410_8 4-5-410_9 4-5-410_10 4-5-410_11 4-5-410_12 4-5-410_13 4-5-410_14 4-5-410_15 4-5-410_16 4-5-410_17 4-5-410_18 4-5-410_19 4-5-410_20 4-5-410_21 4-5-410_22  63.18 63.59 62.33 63.57 63.34 62.89 63.30 63.93 63.80 64.59 64.37 64.01 62.40 63.33 63.07 63.05 62.90 63.10 63.27 63.21 62.79 64.33  23.13 23.38 23.16 23.16 23.13 22.73 22.46 22.69 22.70 22.31 22.51 22.14 23.31 23.45 22.87 23.20 23.34 22.91 23.34 23.11 23.28 22.71  4.97 5.09 5.07 5.10 4.51 4.72 4.57 4.28 4.13 4.27 4.02 4.15 5.06 5.23 4.99 4.86 5.07 5.08 4.80 4.53 4.71 4.45  7.89 8.13 8.22 8.41 8.27 8.16 8.33 8.50 8.52 8.65 8.44 8.62 8.06 8.08 8.17 7.98 8.17 8.17 8.28 8.47 8.27 8.56  0.64 0.63 0.69 0.62 0.69 0.68 0.71 0.72 0.80 0.73 0.71 0.85 0.65 0.61 0.64 0.66 0.68 0.70 0.71 0.64 0.76 0.79  0.03 0.01 0.02 0.00 0.04 0.00 0.00 0.00 0.02 0.02 0.02 0.00 0.03 0.00 0.00 0.00 0.00 0.01 0.03 0.01 0.00 0.02  0.00 0.00 0.01 0.06 0.04 0.01 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.05 0.02 0.00 0.02 0.00 0.00 0.01  0.14 0.25 0.10 0.16 0.19 0.11 0.08 0.16 0.09 0.11 0.00 0.12 0.15 0.04 0.15 0.16 0.09 0.32 0.29 0.13 0.16 0.14  99.98 101.08 99.59 101.08 100.23 99.29 99.46 100.28 100.08 100.67 100.06 99.90 99.66 100.74 99.89 99.96 100.27 100.28 100.74 100.11 99.97 101.01  0.248 0.248 0.244 0.242 0.222 0.233 0.223 0.209 0.202 0.205 0.200 0.200 0.248 0.254 0.243 0.242 0.245 0.245 0.233 0.220 0.229 0.213  0.714 0.716 0.716 0.723 0.737 0.728 0.736 0.750 0.752 0.753 0.758 0.751 0.714 0.711 0.720 0.719 0.716 0.714 0.726 0.743 0.727 0.742  0.038 0.037 0.040 0.035 0.041 0.040 0.041 0.042 0.047 0.042 0.042 0.049 0.038 0.035 0.037 0.039 0.039 0.040 0.041 0.037 0.044 0.045  106  Table A3 continued. Electron microprobe analysis data Label  SiO2  Al2O3  CaO  Na2O  K2O  MgO  MnO  FeO  Total  mol frac An  mol frac Ab  4-5-410_23 4-5-410_24 4-5-410_25 4-5-410_26 4-5-410_27 4-5-410_28 4-5-410_29 4-5-410_30  63.65 64.64 63.67 64.49 64.18 64.50 64.30 64.88  22.91 22.55 22.80 22.73 22.41 22.25 22.34 22.17  4.44 4.02 4.23 4.26 3.91 3.85 3.69 3.83  8.70 8.57 8.54 8.54 8.60 8.52 8.82 8.67  0.72 0.80 0.80 0.70 0.79 0.85 0.82 0.83  0.00 0.03 0.00 0.00 0.00 0.02 0.00 0.02  0.00 0.00 0.00 0.00 0.09 0.00 0.02 0.00  0.12 0.27 0.19 0.19 0.19 0.08 0.19 0.07  100.54 100.87 100.22 100.91 100.16 100.07 100.19 100.48  0.211 0.196 0.205 0.207 0.192 0.190 0.179 0.187  0.748 0.757 0.749 0.752 0.762 0.760 0.774 0.765  mol frac Or 0.041 0.047 0.046 0.041 0.046 0.050 0.047 0.048  4-5-414-1 4-5-414-2  64.43 62.53  21.81 23.67  3.41 5.70  8.77 8.03  0.85 0.61  0.00 0.00  0.00 0.02  0.09 0.15  99.35 100.72  0.168 0.272  0.782 0.693  0.050 0.035  4-5-416-1 4-5-416-2 4-5-416-3  63.76 60.67 62.72  22.29 24.63 23.78  4.37 7.46 5.46  8.72 7.08 7.72  0.83 0.47 0.61  0.02 0.03 0.01  0.00 0.00 0.07  0.15 0.18 0.18  100.14 100.52 100.56  0.207 0.358 0.271  0.747 0.615 0.693  0.047 0.027 0.036  4-4-3501-1 4-4-3501-2  54.78 61.75  28.75 23.96  11.29 5.90  4.82 7.63  0.22 0.57  0.03 0.00  0.01 0.00  0.27 0.40  100.17 100.21  0.557 0.289  0.430 0.677  0.013 0.033  4-4-3504-1 4-4-3504-2  58.02 62.56  26.44 23.37  9.24 5.10  6.00 8.00  0.31 0.72  0.01 0.00  0.00 0.00  0.19 0.23  100.21 99.97  0.452 0.250  0.531 0.709  0.018 0.042  4-4-3505-1 4-4-3505-2  54.81 62.13  28.47 23.52  11.54 5.09  4.92 7.96  0.16 0.53  0.00 0.00  0.00 0.01  0.21 0.08  100.11 99.32  0.559 0.253  0.432 0.716  0.009 0.031  4-4-3509_1 4-4-3509_2 4-4-3509_3 4-4-3509_4 4-4-3509_5 4-4-3509_6 4-4-3509_7  61.18 60.75 61.91 60.72 61.73 60.90 61.27  24.67 24.64 24.68 24.63 24.49 24.50 24.49  6.64 6.58 6.48 6.53 6.35 6.61 6.58  7.21 7.47 7.64 7.21 7.32 7.54 7.56  0.46 0.49 0.47 0.48 0.46 0.39 0.47  0.00 0.03 0.01 0.00 0.00 0.01 0.01  0.07 0.06 0.02 0.03 0.03 0.00 0.00  0.31 0.20 0.14 0.32 0.30 0.12 0.20  100.55 100.22 101.35 99.92 100.69 100.07 100.58  0.328 0.318 0.311 0.324 0.315 0.319 0.316  0.645 0.654 0.663 0.648 0.658 0.659 0.657  0.027 0.028 0.027 0.028 0.027 0.022 0.027  107  Table A3 continued. Electron microprobe analysis data Label  SiO2  Al2O3  CaO  Na2O  K2O  MgO  MnO  FeO  Total  mol frac An  mol frac Ab  4-4-3509_8 4-4-3509_9 4-4-3509_10 4-4-3509_11 4-4-3509_12 4-4-3509_13 4-4-3509_14 4-4-3509_15 4-4-3509_16 4-4-3509_17 4-4-3509_18 4-4-3509_19 4-4-3509_20 4-4-3509_21 4-4-3509_22 4-4-3509_23 4-4-3509_24 4-4-3509_25 4-4-3509_26 4-4-3509_27 4-4-3509_28 4-4-3509_29 4-4-3509_30 4-4-3509_31 4-4-3509_32 4-4-3509_33 4-4-3509_34 4-4-3509_35 4-4-3509_36 4-4-3509_37 4-4-3509_38 4-4-3509_39  60.75 61.47 60.96 61.43 60.50 60.88 61.60 61.72 61.39 61.27 61.02 62.22 57.01 56.31 56.52 56.82 56.47 56.29 57.22 57.53 58.77 59.48 58.59 60.22 60.18 60.21 59.99 60.93 60.16 59.78 59.66 60.97  24.26 24.39 24.32 24.53 24.74 24.00 24.39 24.61 24.25 24.54 24.30 24.31 27.49 27.71 27.77 27.73 27.59 27.35 27.13 26.71 26.13 25.74 25.71 25.32 25.24 24.73 25.20 24.86 24.91 25.03 25.52 24.77  6.26 6.35 6.61 6.42 6.45 6.56 6.52 6.54 6.24 6.42 6.24 6.44 10.15 10.59 10.52 10.22 10.34 10.35 9.78 8.86 8.27 7.85 7.77 7.44 7.39 6.96 6.82 6.85 6.86 7.03 7.45 6.95  7.47 7.53 7.53 7.51 7.65 7.52 7.38 7.63 7.50 7.54 7.37 7.53 5.78 5.72 5.69 5.55 5.64 5.73 5.87 6.09 6.59 6.55 6.93 7.12 7.15 7.17 7.28 7.16 7.23 7.09 7.25 7.35  0.49 0.46 0.40 0.47 0.44 0.45 0.57 0.49 0.49 0.45 0.46 0.57 0.23 0.17 0.22 0.23 0.17 0.19 0.26 0.22 0.31 0.29 0.36 0.33 0.32 0.37 0.44 0.34 0.47 0.39 0.35 0.36  0.00 0.00 0.01 0.00 0.00 0.01 0.01 0.00 0.01 0.02 0.00 0.00 0.03 0.00 0.00 0.01 0.02 0.00 0.00 0.02 0.00 0.02 0.02 0.03 0.02 0.00 0.01 0.01 0.03 0.00 0.03 0.00  0.00 0.01 0.07 0.00 0.03 0.08 0.02 0.02 0.00 0.00 0.00 0.00 0.04 0.00 0.04 0.00 0.00 0.00 0.00 0.04 0.00 0.01 0.03 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00  0.24 0.15 0.27 0.29 0.26 0.10 0.17 0.30 0.30 0.22 0.29 0.25 0.35 0.37 0.38 0.39 0.32 0.32 0.36 0.34 0.24 0.26 0.39 0.34 0.33 0.18 0.19 0.27 0.14 0.22 0.29 0.26  99.47 100.36 100.16 100.64 100.07 99.60 100.65 101.32 100.18 100.46 99.68 101.33 101.07 100.88 101.13 100.95 100.55 100.23 100.61 99.82 100.33 100.20 99.80 100.80 100.63 99.63 99.93 100.44 99.79 99.53 100.56 100.67  0.307 0.309 0.319 0.312 0.310 0.317 0.317 0.313 0.306 0.312 0.310 0.310 0.486 0.501 0.499 0.498 0.498 0.494 0.472 0.440 0.402 0.392 0.375 0.359 0.357 0.342 0.332 0.339 0.335 0.346 0.355 0.336  0.664 0.664 0.658 0.661 0.665 0.657 0.650 0.660 0.665 0.662 0.663 0.657 0.501 0.490 0.489 0.489 0.492 0.495 0.513 0.547 0.580 0.591 0.605 0.622 0.625 0.637 0.642 0.641 0.638 0.631 0.625 0.643  108  mol frac Or 0.029 0.027 0.023 0.027 0.025 0.026 0.033 0.028 0.029 0.026 0.027 0.033 0.013 0.010 0.012 0.013 0.010 0.011 0.015 0.013 0.018 0.017 0.021 0.019 0.018 0.022 0.026 0.020 0.027 0.023 0.020 0.021  Table A3 continued. Electron microprobe analysis data Label 4-4-3509_40 4-4-3509_41 4-4-3509_42 4-4-3509_43 4-4-3509_44 4-4-3509_45 4-4-3509_46 4-4-3509_47 4-4-3509_48 4-4-3509_49 4-4-3509_50 4-4-3509_51 4-4-3509_52 4-4-3509_53 4-4-3509_54 4-4-3509_55 4-4-3509_56 4-4-3509_57 4-4-3509_58 4-4-3509_59 4-4-3509_60 4-4-3509_61 4-4-3509_62 4-4-3509_63 4-4-3509_64 4-4-3509_65 4-4-3509_66 4-4-3509_67 4-4-3509_68 4-4-3509_69 4-4-3509_70 4-4-3509_71 4-4-3509_72  SiO2 62.28 62.18 62.32 62.87 62.69 63.72 62.40 62.14 61.15 60.76 60.93 61.00 61.31 61.87 61.34 62.08 62.03 62.54 61.58 61.79 61.75 61.27 60.67 61.37 62.87 62.71 62.22 62.69 62.92 63.19 63.85 63.64  Al2O3 23.85 23.88 23.82 23.44 23.83 22.88 23.73 23.76 24.22 24.49 24.73 24.56 24.46 24.16 24.34 24.15 23.72 23.83 23.97 23.88 24.13 24.11 24.36 23.85 23.54 23.52 23.21 23.15 23.46 23.00 23.21 23.17  CaO 5.92 5.89 5.72 5.52 5.50 4.80 5.72 5.78 5.91 6.77 6.83 6.67 6.40 6.34 6.12 5.82 5.55 5.63 5.63 5.59 5.97 5.64 5.72 5.77 5.39 5.11 5.45 4.99 4.75 4.78 4.90 4.49  Na2O 7.63 7.61 7.60 8.18 7.89 8.42 8.02 7.70 7.90 7.59 7.44 7.42 7.76 7.92 7.53 7.94 7.88 7.92 7.63 7.56 7.84 7.71 7.33 8.08 7.87 8.36 7.99 8.12 8.49 8.22 8.52 8.38  K2O 0.45 0.41 0.56 0.52 0.52 0.61 0.58 0.56 0.48 0.46 0.43 0.45 0.47 0.51 0.45 0.49 0.48 0.52 0.52 0.57 0.51 0.45 0.49 0.56 0.56 0.63 0.57 0.58 0.62 0.71 0.62 0.62  MgO 0.00 0.00 0.05 0.02 0.00 0.00 0.01 0.00 0.00 0.01 0.00 0.02 0.01 0.00 0.03 0.00 0.00 0.00 0.01 0.03 0.02 0.00 0.01 0.00 0.00 0.02 0.00 0.00 0.00 0.04 0.00 0.00  MnO 0.03 0.02 0.00 0.00 0.01 0.00 0.02 0.00 0.00 0.06 0.00 0.01 0.02 0.06 0.02 0.02 0.01 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.02 0.00 0.03 0.00 0.07 0.00 0.01  FeO 0.03 0.23 0.23 0.13 0.34 0.31 0.09 0.18 0.24 0.12 0.32 0.23 0.22 0.23 0.23 0.25 0.17 0.21 0.25 0.24 0.30 0.18 0.22 0.30 0.23 0.24 0.23 0.14 0.11 0.22 0.23 0.11  109  Total 100.19 100.22 100.30 100.68 100.78 100.74 100.57 100.13 99.90 100.25 100.69 100.36 100.64 101.09 100.05 100.76 99.85 100.64 99.59 99.68 100.53 99.35 98.80 99.94 100.48 100.62 99.68 99.70 100.35 100.22 101.33 100.42  mol frac An 0.292 0.292 0.284 0.264 0.270 0.231 0.273 0.284 0.284 0.322 0.328 0.323 0.305 0.298 0.302 0.280 0.272 0.274 0.281 0.280 0.288 0.280 0.292 0.274 0.266 0.244 0.265 0.245 0.228 0.233 0.233 0.220  mol frac Ab 0.681 0.684 0.683 0.707 0.700 0.734 0.694 0.684 0.688 0.652 0.647 0.651 0.669 0.674 0.672 0.692 0.700 0.696 0.688 0.686 0.683 0.693 0.678 0.694 0.702 0.721 0.702 0.721 0.737 0.726 0.732 0.744  mol frac Or 0.026 0.024 0.033 0.030 0.030 0.035 0.033 0.033 0.028 0.026 0.025 0.026 0.027 0.029 0.026 0.028 0.028 0.030 0.031 0.034 0.029 0.027 0.030 0.032 0.033 0.036 0.033 0.034 0.035 0.041 0.035 0.036  Table A3 continued. Electron microprobe analysis data Label 4-4-3509_73 4-4-3509_74 4-4-3509_75 4-4-3509_76 4-4-3509_77 4-4-3509_78 4-4-3509_79 4-4-3509_80  SiO2 63.73 63.85 64.56 63.57 63.93 70.06 77.67 76.61  Al2O3 22.54 22.74 22.84 22.56 22.52 17.84 11.95 12.02  CaO 4.36 4.27 4.29 4.08 4.20 2.83 0.67 0.69  Na2O 8.10 8.44 8.70 8.39 8.18 5.97 3.32 2.77  K2O 0.80 0.73 0.72 0.76 0.86 1.83 3.90 4.08  MgO 0.01 0.04 0.00 0.00 0.01 0.01 0.06 0.07  MnO 0.00 0.09 0.00 0.08 0.00 0.02 0.09 0.06  FeO 0.18 0.28 0.20 0.06 0.20 0.50 0.92 1.18  Total 99.72 100.44 101.31 99.50 99.91 99.06 98.57 97.47  mol frac An 0.218 0.209 0.205 0.202 0.210 0.179 0.059 0.065  mol frac Ab 0.734 0.748 0.754 0.753 0.739 0.683 0.531 0.475  4-4-3515-1 4-4-3515-2 4-4-3515-3  61.03 55.51 63.36  25.03 28.22 23.02  6.92 10.69 5.09  7.23 5.52 8.42  0.42 0.21 0.66  0.01 0.00 0.00  0.06 0.03 0.04  0.29 0.29 0.05  100.98 100.47 100.64  0.338 0.511 0.241  0.638 0.477 0.722  0.024 0.012 0.037  4-4-3519-1_1 4-4-3519-1_2 4-4-3519-1_3 4-4-3519-1_4 4-4-3519-1_5 4-4-3519-1_6 4-4-3519-1_7 4-4-3519-1_8 4-4-3519-1_9 4-4-3519-1_10 4-4-3519-1_11 4-4-3519-1_12 4-4-3519-1_13 4-4-3519-1_14 4-4-3519-1_15 4-4-3519-1_16 4-4-3519-1_17 4-4-3519-1_18 4-4-3519-1_19 4-4-3519-1_20  60.58 61.47 60.83 61.16 61.34 61.28 61.43 60.88 60.67 61.78 60.89 61.09 60.95 60.42 61.12 61.55 60.84 61.01 61.23 62.28  24.44 24.37 24.52 24.53 24.45 24.44 24.61 24.33 24.55 24.38 24.65 24.65 24.72 24.72 24.51 24.51 24.63 24.64 24.58 23.75  6.69 6.46 6.49 6.23 6.68 6.42 6.70 6.39 6.61 6.52 6.38 6.75 6.51 6.42 6.60 6.41 6.50 6.78 6.40 5.91  7.72 7.58 7.44 7.48 7.69 7.53 7.70 7.69 7.72 7.73 7.51 7.45 7.35 7.57 7.30 7.50 7.52 7.24 7.66 7.64  0.42 0.43 0.44 0.42 0.46 0.40 0.44 0.48 0.36 0.41 0.42 0.45 0.47 0.44 0.45 0.41 0.45 0.41 0.42 0.47  0.01 0.00 0.01 0.00 0.00 0.00 0.01 0.01 0.00 0.01 0.01 0.01 0.01 0.00 0.00 0.04 0.00 0.02 0.00 0.00  0.00 0.02 0.01 0.04 0.00 0.04 0.02 0.02 0.00 0.06 0.00 0.00 0.00 0.04 0.00 0.04 0.02 0.04 0.01 0.00  0.32 0.20 0.29 0.22 0.26 0.22 0.24 0.26 0.21 0.27 0.22 0.16 0.18 0.17 0.05 0.16 0.06 0.15 0.13 0.20  100.18 100.54 100.03 100.06 100.88 100.34 101.15 100.06 100.12 101.16 100.08 100.57 100.19 99.79 100.04 100.63 100.01 100.29 100.44 100.24  0.316 0.312 0.317 0.307 0.316 0.313 0.317 0.306 0.315 0.311 0.312 0.325 0.320 0.311 0.324 0.313 0.315 0.333 0.308 0.291  0.660 0.663 0.658 0.668 0.658 0.664 0.659 0.667 0.665 0.666 0.664 0.649 0.653 0.664 0.649 0.663 0.659 0.643 0.668 0.681  0.024 0.025 0.026 0.025 0.026 0.023 0.025 0.027 0.020 0.023 0.024 0.026 0.028 0.025 0.026 0.024 0.026 0.024 0.024 0.028  110  mol frac Or 0.048 0.043 0.041 0.045 0.051 0.138 0.410 0.460  Table A3 continued. Electron microprobe analysis data Label 4-4-3519-1_21 4-4-3519-1_22 4-4-3519-1_23 4-4-3519-1_24 4-4-3519-1_25 4-4-3519-1_26 4-4-3519-1_27 4-4-3519-1_28 4-4-3519-1_29 4-4-3519-1_30 4-4-3519-1_31 4-4-3519-1_32 4-4-3519-1_33 4-4-3519-1_34 4-4-3519-1_35 4-4-3519-1_36 4-4-3519-1_37 4-4-3519-1_38 4-4-3519-1_39 4-4-3519-1_40 4-4-3519-1_41 4-4-3519-1_42 4-4-3519-1_43 4-4-3519-1_44 4-4-3519-1_45 4-4-3519-1_46 4-4-3519-1_47 4-4-3519-1_48 4-4-3519-1_49 4-4-3519-1_50 4-4-3519-1_51 4-4-3519-1_52 4-4-3519-1_53  SiO2 61.65 61.99 61.88 61.73 61.32 61.62 61.85 61.96 61.32 62.23 62.01 61.68 62.16 62.57 62.04 62.24 62.17 62.36 62.39 62.61 61.49 62.24 62.60 62.88 62.09 61.74 63.05 63.97 62.97 63.46 64.22 62.92 63.21  Al2O3 24.25 24.17 24.20 23.95 24.00 24.50 23.84 23.99 24.06 24.00 23.75 23.70 23.91 23.65 23.59 23.90 23.95 23.69 23.84 23.57 23.70 23.50 23.81 23.80 23.78 23.74 23.38 22.77 22.95 22.74 23.01 23.10 22.75  CaO 6.15 6.04 5.96 5.87 6.19 5.99 5.99 5.83 6.17 5.87 5.76 5.91 5.62 5.42 5.64 5.49 5.77 5.56 5.61 5.29 5.70 5.66 5.31 5.72 5.65 5.63 4.75 4.62 4.61 4.46 4.45 4.71 4.75  Na2O 7.81 7.71 7.97 7.67 7.69 7.77 7.88 7.86 7.55 7.91 7.61 7.67 8.19 8.09 7.71 7.91 7.86 8.16 7.63 8.11 8.02 7.57 7.84 7.73 7.73 8.06 8.46 8.44 8.59 8.58 8.83 8.17 8.20  K2O 0.47 0.54 0.49 0.52 0.57 0.46 0.56 0.48 0.49 0.51 0.45 0.54 0.53 0.50 0.59 0.51 0.56 0.49 0.54 0.54 0.42 0.60 0.54 0.56 0.51 0.54 0.60 0.65 0.59 0.64 0.66 0.66 0.66  MgO 0.00 0.02 0.01 0.00 0.00 0.01 0.01 0.00 0.00 0.00 0.00 0.02 0.01 0.02 0.01 0.00 0.00 0.01 0.00 0.02 0.03 0.00 0.07 0.00 0.03 0.02 0.04 0.00 0.01 0.00 0.00 0.00 0.00  MnO 0.01 0.03 0.00 0.05 0.00 0.00 0.00 0.00 0.04 0.03 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.00 0.00 0.02 0.00 0.00 0.06 0.00 0.03 0.00 0.00  FeO 0.26 0.02 0.22 0.15 0.25 0.06 0.23 0.11 0.11 0.16 0.21 0.16 0.26 0.19 0.16 0.20 0.20 0.17 0.19 0.22 0.15 0.16 0.18 0.16 0.21 0.16 0.21 0.17 0.19 0.06 0.24 0.19 0.08  111  Total 100.60 100.51 100.73 99.95 100.03 100.40 100.35 100.22 99.74 100.71 99.80 99.68 100.70 100.44 99.73 100.26 100.51 100.44 100.20 100.37 99.51 99.74 100.37 100.84 99.99 99.92 100.48 100.61 99.98 99.94 101.44 99.76 99.66  mol frac An 0.295 0.293 0.284 0.288 0.298 0.291 0.286 0.283 0.302 0.282 0.287 0.289 0.267 0.262 0.278 0.269 0.279 0.266 0.280 0.257 0.275 0.282 0.264 0.281 0.279 0.270 0.229 0.224 0.221 0.215 0.210 0.232 0.233  mol frac Ab 0.678 0.676 0.688 0.681 0.670 0.683 0.682 0.690 0.669 0.689 0.686 0.679 0.703 0.709 0.688 0.701 0.688 0.706 0.688 0.712 0.701 0.682 0.704 0.687 0.691 0.699 0.737 0.739 0.745 0.748 0.753 0.729 0.728  mol frac Or 0.027 0.031 0.028 0.030 0.033 0.027 0.032 0.028 0.029 0.029 0.027 0.032 0.030 0.029 0.035 0.030 0.032 0.028 0.032 0.031 0.024 0.036 0.032 0.033 0.030 0.031 0.034 0.037 0.034 0.037 0.037 0.039 0.039  Table A3 continued. Electron microprobe analysis data Label 4-4-3519-1_54 4-4-3519-1_55 4-4-3519-1_56 4-4-3519-1_57 4-4-3519-1_58 4-4-3519-1_59 4-4-3519-1_60  SiO2 63.83 63.32 64.12 63.10 64.02 63.82 64.17  Al2O3 22.99 22.73 23.00 22.68 22.43 22.53 22.79  CaO 4.69 4.38 4.34 4.56 4.30 4.24 4.52  Na2O 8.24 8.52 8.44 8.17 8.50 8.53 8.84  K2O 0.69 0.67 0.75 0.74 0.68 0.71 0.75  MgO 0.00 0.01 0.00 0.02 0.00 0.00 0.00  MnO 0.00 0.00 0.05 0.00 0.05 0.00 0.03  FeO 0.23 0.23 0.07 0.21 0.18 0.20 0.19  Total 100.67 99.86 100.76 99.49 100.18 100.02 101.28  mol frac An 0.230 0.213 0.212 0.226 0.210 0.207 0.211  mol frac Ab 0.730 0.749 0.745 0.731 0.751 0.752 0.747  mol frac Or 0.040 0.039 0.044 0.044 0.040 0.041 0.042  4-4-3519-2_1 4-4-3519-2_2 4-4-3519-2_3 4-4-3519-2_4 4-4-3519-2_5 4-4-3519-2_6 4-4-3519-2_7 4-4-3519-2_8 4-4-3519-2_9 4-4-3519-2_10 4-4-3519-2_11 4-4-3519-2_12 4-4-3519-2_13 4-4-3519-2_14 4-4-3519-2_15 4-4-3519-2_16 4-4-3519-2_17 4-4-3519-2_18 4-4-3519-2_19 4-4-3519-2_20 4-4-3519-2_21 4-4-3519-2_22 4-4-3519-2_23 4-4-3519-2_24 4-4-3519-2_25  61.00 61.16 61.38 61.19 61.35 61.92 60.46 61.20 61.00 61.10 60.45 61.97 62.15 61.61 61.76 62.11 61.56 61.91 61.92 62.09 62.25 62.71 61.53 62.17 62.32  24.36 24.48 24.48 24.71 24.39 24.16 24.68 24.29 24.14 24.40 24.40 24.04 23.69 24.14 24.00 24.08 24.28 23.74 23.75 24.16 23.60 23.28 23.48 23.97 23.93  6.80 6.67 6.45 6.77 6.53 6.34 6.46 6.52 6.64 6.68 6.79 5.74 5.91 5.87 6.15 6.12 6.13 6.19 5.99 5.98 5.65 5.72 5.79 5.88 5.65  7.31 7.27 7.61 7.56 7.56 7.41 7.48 7.45 7.51 7.45 7.44 7.74 7.66 7.72 7.75 8.05 7.74 7.82 7.80 8.08 7.93 7.91 8.10 7.73 8.10  0.40 0.45 0.44 0.48 0.42 0.43 0.49 0.41 0.45 0.39 0.45 0.45 0.42 0.58 0.42 0.48 0.41 0.49 0.45 0.46 0.47 0.51 0.57 0.48 0.53  0.00 0.00 0.04 0.03 0.00 0.00 0.00 0.04 0.05 0.00 0.02 0.02 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.00 0.01 0.03 0.00 0.00 0.01  0.03 0.08 0.09 0.00 0.00 0.00 0.00 0.04 0.04 0.00 0.00 0.06 0.00 0.01 0.00 0.04 0.01 0.00 0.02 0.00 0.00 0.00 0.00 0.06 0.00  0.27 0.17 0.16 0.28 0.15 0.23 0.26 0.18 0.12 0.21 0.29 0.24 0.34 0.21 0.18 0.06 0.13 0.27 0.14 0.16 0.34 0.15 0.11 0.21 0.14  100.16 100.27 100.65 101.02 100.41 100.48 99.83 100.13 99.95 100.23 99.85 100.25 100.18 100.13 100.25 100.95 100.27 100.43 100.06 100.94 100.25 100.32 99.58 100.51 100.67  0.332 0.328 0.311 0.322 0.315 0.313 0.314 0.318 0.320 0.324 0.327 0.283 0.292 0.286 0.298 0.288 0.297 0.296 0.290 0.283 0.275 0.277 0.274 0.288 0.270  0.645 0.646 0.664 0.651 0.661 0.662 0.658 0.658 0.654 0.654 0.648 0.691 0.684 0.681 0.678 0.685 0.679 0.676 0.684 0.691 0.698 0.694 0.694 0.684 0.700  0.023 0.026 0.025 0.027 0.024 0.025 0.028 0.024 0.026 0.023 0.026 0.026 0.025 0.034 0.024 0.027 0.024 0.028 0.026 0.026 0.027 0.029 0.032 0.028 0.030  112  Table A3 continued. Electron microprobe analysis data Label 7-2-101-1 7-2-101-2 7-2-101-3  SiO2 63.15 62.23 63.21  Al2O3 23.08 24.04 23.51  CaO 4.37 5.20 4.99  Na2O 8.41 8.26 7.99  K2O 0.63 0.58 0.66  MgO 0.00 0.00 0.01  MnO 0.00 0.01 0.00  FeO 0.18 0.19 0.24  Total 99.82 100.52 100.62  mol frac An 0.215 0.250 0.247  mol frac Ab 0.748 0.717 0.715  mol frac Or 0.037 0.033 0.039  7-5-402_1 7-5-402_2 7-5-402_3 7-5-402_4 7-5-402_5 7-5-402_6 7-5-402_7 7-5-402_8 7-5-402_9 7-5-402_10 7-5-402_11 7-5-402_12 7-5-402_13 7-5-402_14 7-5-402_15 7-5-402_16 7-5-402_17 7-5-402_18 7-5-402_19 7-5-402_20 7-5-402_21 7-5-402_22 7-5-402_23 7-5-402_24 7-5-402_25 7-5-402_26 7-5-402_27 7-5-402_28 7-5-402_29  63.50 64.33 63.66 64.63 63.98 63.81 64.37 63.78 63.46 63.53 64.41 63.61 63.75 63.07 64.17 63.82 64.50 64.25 63.93 64.54 65.03 64.41 63.73 63.93 64.51 64.17 64.56 64.96 64.43  23.39 23.86 23.65 23.57 23.78 23.35 23.22 23.88 23.74 23.52 23.56 23.71 23.92 23.38 23.39 23.23 23.29 23.36 23.47 23.60 23.19 23.11 23.43 23.18 23.15 23.07 22.83 23.10 23.27  5.08 4.88 4.83 4.84 4.87 5.01 4.99 5.17 5.19 5.18 5.16 5.35 5.03 5.25 4.91 4.78 4.64 4.71 4.84 4.61 4.77 4.75 4.58 4.53 4.46 4.62 4.17 3.97 4.14  7.94 8.08 8.15 8.16 7.96 8.16 8.23 8.40 7.94 7.96 7.95 8.03 8.10 8.13 8.28 8.31 8.01 8.26 8.24 8.30 7.95 8.50 8.05 8.18 8.16 8.37 8.78 8.24 8.73  0.59 0.61 0.60 0.63 0.67 0.56 0.65 0.62 0.59 0.60 0.65 0.62 0.57 0.66 0.71 0.71 0.76 0.70 0.69 0.66 0.66 0.73 0.76 0.63 0.71 0.77 0.75 0.75 0.73  0.00 0.00 0.00 0.02 0.02 0.00 0.00 0.00 0.00 0.03 0.01 0.00 0.01 0.01 0.02 0.02 0.00 0.00 0.03 0.03 0.01 0.00 0.02 0.00 0.00 0.00 0.00 0.01 0.00  0.00 0.07 0.00 0.05 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.03 0.00 0.00 0.05 0.02 0.01 0.01 0.06 0.00 0.00 0.00 0.00 0.00 0.04 0.00 0.00 0.00 0.01  0.20 0.07 0.09 0.12 0.06 0.13 0.09 0.18 0.17 0.10 0.06 0.18 0.03 0.17 0.16 0.08 0.18 0.14 0.18 0.16 0.20 0.21 0.12 0.19 0.14 0.06 0.08 0.16 0.12  100.70 101.90 100.98 102.03 101.34 101.02 101.55 102.02 101.09 100.91 101.81 101.52 101.41 100.67 101.69 100.99 101.38 101.42 101.45 101.90 101.82 101.72 100.69 100.64 101.16 101.06 101.17 101.20 101.42  0.252 0.241 0.238 0.238 0.243 0.245 0.242 0.245 0.256 0.255 0.254 0.260 0.247 0.253 0.237 0.231 0.232 0.230 0.235 0.226 0.239 0.226 0.228 0.226 0.222 0.223 0.199 0.201 0.199  0.713 0.723 0.727 0.725 0.718 0.722 0.721 0.720 0.709 0.710 0.708 0.705 0.720 0.709 0.723 0.728 0.723 0.730 0.725 0.736 0.721 0.732 0.727 0.737 0.736 0.732 0.758 0.754 0.759  0.035 0.036 0.035 0.037 0.040 0.033 0.038 0.035 0.035 0.035 0.038 0.036 0.033 0.038 0.041 0.041 0.045 0.041 0.040 0.039 0.039 0.041 0.045 0.037 0.042 0.044 0.043 0.045 0.042  113  Table A3 continued. Electron microprobe analysis data Label 7-5-402_30 7-5-402_31 7-5-402_32 7-5-402_33 7-5-402_34 7-5-402_35 7-5-402_36 7-5-402_37 7-5-402_38 7-5-402_39 7-5-402_40 7-5-402_41 7-5-402_42 7-5-402_43 7-5-402_44 7-5-402_45 7-5-402_46 7-5-402_47 7-5-402_48 7-5-402_49 7-5-402_50  SiO2 64.42 64.37 64.07 64.89 64.82 64.57 65.27 64.50 66.69 64.01 64.36 64.79 64.71 64.77 64.27 64.40 64.24 64.58 64.80 64.76  Al2O3 23.05 22.73 22.94 22.68 22.56 22.76 22.67 22.55 20.22 23.59 22.76 22.62 22.49 22.51 22.97 23.33 23.21 23.10 22.83 22.66  CaO 4.17 4.09 4.19 4.16 4.13 3.98 3.99 4.06 3.88 4.04 4.19 3.91 3.70 3.93 4.10 4.61 4.47 4.21 4.06 4.08  Na2O 8.49 8.51 8.48 8.69 8.58 8.16 8.63 8.67 9.57 8.12 8.59 8.54 8.57 8.65 8.67 8.51 8.41 8.70 8.73 8.63  K2O 0.76 0.72 0.86 0.86 0.71 0.89 0.83 0.80 0.77 0.76 0.83 0.76 0.76 0.80 0.87 0.68 0.76 0.70 0.75 0.81  MgO 0.02 0.00 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.01 0.00 0.01 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.01  MnO 0.00 0.06 0.05 0.00 0.10 0.00 0.00 0.05 0.00 0.01 0.00 0.01 0.00 0.00 0.00 0.05 0.05 0.00 0.02 0.05  FeO 0.15 0.19 0.11 0.16 0.24 0.11 0.19 0.18 0.20 0.05 0.10 0.23 0.12 0.13 0.09 0.15 0.14 0.15 0.10 0.07  Total 101.07 100.68 100.69 101.44 101.15 100.47 101.59 100.81 101.32 100.59 100.83 100.87 100.35 100.79 100.98 101.74 101.29 101.44 101.28 101.06  mol frac An 0.204 0.201 0.204 0.199 0.201 0.201 0.194 0.196 0.175 0.206 0.202 0.193 0.184 0.191 0.197 0.221 0.217 0.203 0.196 0.198  mol frac Ab 0.752 0.757 0.746 0.752 0.757 0.746 0.758 0.758 0.783 0.748 0.750 0.763 0.771 0.762 0.753 0.740 0.739 0.757 0.761 0.756  mol frac Or 0.044 0.042 0.050 0.049 0.041 0.054 0.048 0.046 0.042 0.046 0.048 0.045 0.045 0.046 0.050 0.039 0.044 0.040 0.043 0.047  7-5-403-1 7-5-403-2  63.56 57.69  23.46 27.38  4.73 9.30  8.58 6.01  0.77 0.26  0.00 0.02  0.03 0.00  0.15 0.29  101.28 100.97  0.223 0.454  0.733 0.531  0.043 0.015  7-5-404-1 7-5-404-2  63.69 64.28  22.87 22.92  4.40 4.10  8.32 8.38  0.85 0.71  0.00 0.00  0.01 0.00  0.17 0.05  100.30 100.45  0.215 0.204  0.736 0.754  0.049 0.042  7-5-405_1 7-5-405_2 7-5-405_3 7-5-405_4 7-5-405_5  60.19 63.37 63.12 63.01 63.22  24.98 23.65 23.50 23.37 23.49  6.97 4.95 4.98 4.98 5.02  7.25 7.90 7.88 8.07 7.97  0.52 0.75 0.75 0.87 0.85  0.03 0.00 0.00 0.00 0.00  0.00 0.00 0.09 0.00 0.00  0.06 0.15 0.13 0.15 0.08  99.99 100.77 100.45 100.46 100.64  0.337 0.246 0.247 0.242 0.245  0.634 0.710 0.708 0.708 0.705  0.030 0.044 0.044 0.050 0.050  114  Table A3 continued. Electron microprobe analysis data Label 7-5-405_6 7-5-405_7 7-5-405_8 7-5-405_9 7-5-405_10 7-5-405_11 7-5-405_12 7-5-405_13 7-5-405_14 7-5-405_15 7-5-405_16 7-5-405_17 7-5-405_18 7-5-405_19 7-5-405_20 7-5-405_21 7-5-405_22 7-5-405_23 7-5-405_24 7-5-405_25 7-5-405_26 7-5-405_27 7-5-405_28 7-5-405_29 7-5-405_30 7-5-405_31 7-5-405_32 7-5-405_33 7-5-405_34 7-5-405_35 7-5-405_36 7-5-405_37 7-5-405_38  SiO2 63.08 63.20 62.68 63.55 62.54 62.83 62.57 62.35 62.51 62.37 61.89 62.02 62.94 62.71 63.36 62.84 63.48 63.22 62.95 62.59 63.19 62.50 62.90 62.39 62.85 63.17 62.41 62.18 62.22 62.32 62.56 62.42 62.60  Al2O3 23.18 23.10 23.77 23.62 23.87 24.08 23.84 23.82 23.98 24.10 24.48 23.32 23.58 23.89 23.79 23.68 23.77 23.97 23.94 24.09 23.64 23.72 24.00 24.08 23.85 23.88 24.23 23.77 23.99 24.02 24.06 24.15 24.11  CaO 4.80 4.81 5.52 5.66 5.39 5.56 5.52 5.44 5.63 5.86 5.73 5.25 4.87 5.14 5.27 5.18 5.35 5.29 5.39 5.16 5.30 5.76 5.64 5.74 5.73 5.37 5.33 5.44 5.31 5.46 5.61 5.62 5.83  Na2O 8.08 7.80 7.99 8.06 7.69 7.77 7.72 7.84 7.81 7.71 7.67 8.02 7.83 7.77 7.94 7.83 7.99 7.88 7.99 7.87 8.28 7.85 7.81 7.89 7.82 7.88 7.74 7.81 7.88 7.73 7.82 7.90 7.74  K2O 0.78 0.80 0.69 0.76 0.77 0.75 0.66 0.65 0.72 0.70 0.61 0.71 0.77 0.74 0.79 0.73 0.72 0.79 0.70 0.70 0.74 0.66 0.71 0.63 0.61 0.65 0.71 0.76 0.79 0.67 0.69 0.64 0.64  MgO 0.00 0.00 0.00 0.00 0.03 0.00 0.00 0.00 0.00 0.01 0.02 0.00 0.01 0.00 0.00 0.00 0.00 0.02 0.02 0.00 0.00 0.01 0.02 0.01 0.01 0.00 0.01 0.01 0.00 0.01 0.02 0.00 0.00  MnO 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.00 0.05 0.01 0.00 0.00 0.01 0.03 0.03 0.00 0.07 0.01 0.00 0.00 0.00 0.04 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.02  FeO 0.20 0.25 0.15 0.30 0.14 0.18 0.13 0.17 0.22 0.19 0.16 0.23 0.18 0.22 0.12 0.18 0.26 0.30 0.32 0.18 0.08 0.17 0.14 0.14 0.29 0.18 0.21 0.14 0.17 0.16 0.25 0.27 0.19  115  Total 100.11 99.97 100.81 101.96 100.45 101.17 100.44 100.26 100.86 100.96 100.56 99.59 100.20 100.48 101.29 100.45 101.60 101.51 101.32 100.66 101.25 100.66 101.20 100.87 101.19 101.13 100.63 100.09 100.35 100.38 101.01 100.99 101.12  mol frac An 0.236 0.242 0.265 0.268 0.267 0.271 0.272 0.267 0.273 0.284 0.282 0.255 0.244 0.256 0.256 0.256 0.259 0.258 0.261 0.255 0.250 0.278 0.274 0.276 0.278 0.263 0.264 0.266 0.259 0.270 0.273 0.272 0.283  mol frac Ab 0.719 0.710 0.695 0.690 0.688 0.685 0.689 0.695 0.685 0.676 0.683 0.704 0.710 0.700 0.698 0.701 0.700 0.696 0.699 0.704 0.708 0.685 0.686 0.688 0.687 0.699 0.694 0.690 0.695 0.691 0.688 0.691 0.680  mol frac Or 0.046 0.048 0.040 0.043 0.045 0.044 0.039 0.038 0.042 0.040 0.036 0.041 0.046 0.044 0.046 0.043 0.042 0.046 0.040 0.041 0.042 0.038 0.041 0.036 0.035 0.038 0.042 0.044 0.046 0.039 0.040 0.037 0.037  Table A3 continued. Electron microprobe analysis data Label 7-5-405_39 7-5-405_40 7-5-405_41 7-5-405_42 7-5-405_43 7-5-405_44 7-5-405_45 7-5-405_46 7-5-405_47 7-5-405_48 7-5-405_49 7-5-405_50 7-5-405-2_1 7-5-405-2_2 7-5-405-2_3 7-5-405-2_4 7-5-405-2_5 7-5-405-2_6 7-5-405-2_7 7-5-405-2_8 7-5-405-2_9 7-5-405-2_10 7-5-405-2_11 7-5-405-2_12 7-5-405-2_13 7-5-405-2_14 7-5-405-2_15 7-5-405-2_16 7-5-405-2_17 7-5-405-2_18 7-5-405-2_19 7-5-405-2_20 7-5-405-2_21  SiO2 63.10 63.51 62.74 63.49 61.88 61.43 62.13 61.59 62.41 62.08 62.29 59.10 58.45 59.36 59.09 58.77 58.46 59.20 58.22 58.32 57.99 58.92 58.37 61.36 60.41 61.26 63.39 63.50 64.30 64.36 64.55 63.54  Al2O3 24.22 23.48 23.82 23.47 23.59 24.15 24.66 24.59 24.31 23.97 23.80 26.74 26.75 26.72 26.64 26.96 27.26 27.04 27.19 27.13 26.97 26.67 26.09 25.04 25.26 24.60 23.70 23.82 23.66 23.41 23.27 23.26  CaO 5.54 5.29 5.34 5.21 5.50 5.83 6.30 6.18 5.92 5.81 5.62 8.64 8.52 8.45 8.59 8.95 8.94 9.22 9.06 9.20 9.04 8.95 8.23 6.52 7.27 6.04 5.37 5.17 5.02 5.08 5.03 5.02  Na2O 7.97 8.03 7.60 7.95 7.62 7.80 7.62 7.59 7.69 7.41 7.77 6.37 6.47 6.10 6.41 6.18 6.00 6.03 5.88 6.09 6.13 6.02 6.58 7.32 7.16 7.60 7.79 7.79 7.84 7.87 7.90 8.18  K2O 0.73 0.77 0.70 0.78 0.67 0.62 0.54 0.57 0.69 0.61 0.68 0.44 0.42 0.33 0.36 0.37 0.40 0.40 0.31 0.43 0.31 0.26 0.44 0.56 0.54 0.49 0.64 0.70 0.69 0.72 0.84 0.74  MgO 0.00 0.00 0.01 0.01 0.01 0.00 0.00 0.01 0.02 0.00 0.00 0.05 0.00 0.00 0.01 0.01 0.00 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.00  MnO 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.01 0.03 0.00 0.06 0.00 0.06 0.01 0.02 0.03 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.07 0.00 0.00 0.00 0.00 0.01 0.00  FeO 0.08 0.16 0.19 0.20 0.14 0.23 0.15 0.32 0.02 0.13 0.12 0.24 0.11 0.11 0.22 0.17 0.21 0.08 0.28 0.14 0.20 0.11 0.27 0.25 0.17 0.29 0.21 0.28 0.31 0.16 0.15 0.23  116  Total 101.65 101.24 100.39 101.12 99.41 100.05 101.41 100.87 101.08 100.05 100.27 101.63 100.72 101.11 101.33 101.43 101.31 101.99 100.94 101.32 100.65 100.95 99.99 101.04 100.80 100.35 101.13 101.26 101.83 101.61 101.73 100.97  mol frac An 0.266 0.255 0.268 0.254 0.274 0.282 0.304 0.300 0.287 0.291 0.274 0.418 0.411 0.425 0.417 0.435 0.441 0.447 0.451 0.444 0.441 0.444 0.398 0.319 0.348 0.296 0.266 0.257 0.251 0.252 0.248 0.243  mol frac Ab 0.692 0.701 0.690 0.701 0.687 0.682 0.665 0.667 0.674 0.672 0.686 0.557 0.565 0.555 0.563 0.544 0.536 0.530 0.530 0.532 0.541 0.541 0.576 0.648 0.621 0.675 0.697 0.701 0.708 0.706 0.703 0.715  mol frac Or 0.042 0.044 0.042 0.045 0.040 0.036 0.031 0.033 0.040 0.036 0.040 0.025 0.024 0.020 0.021 0.021 0.024 0.023 0.018 0.025 0.018 0.015 0.025 0.033 0.031 0.029 0.038 0.042 0.041 0.043 0.049 0.043  Table A3 continued. Electron microprobe analysis data Label 7-5-405-2_22 7-5-405-2_23 7-5-405-2_24 7-5-405-2_25 7-5-405-2_26 7-5-405-2_27 7-5-405-2_28 7-5-405-2_29 7-5-405-2_30 7-5-405-2_31 7-5-405-2_32 7-5-405-2_33 7-5-405-2_34 7-5-405-2_35 7-5-405-2_36 7-5-405-2_37 7-5-405-2_38 7-5-405-2_39 7-5-405-2_40 7-5-405-2_41 7-5-405-2_42 7-5-405-2_43 7-5-405-2_44 7-5-405-2_45 7-5-405-2_46 7-5-405-2_47 7-5-405-2_48 7-5-405-2_49 7-5-405-2_50 7-5-405-2_51 7-5-405-2_52 7-5-405-2_53 7-5-405-2_54  SiO2 63.14 63.45 63.67 63.36 63.23 62.35 62.72 62.82 62.68 62.24 62.54 62.48 62.68 62.68 62.82 62.80 63.15 62.79 63.35 62.79 62.86 62.92 62.88 63.10 62.28 62.55 62.74 62.10 63.32 62.29 61.89 62.60 62.62  Al2O3 23.23 23.39 23.34 23.22 23.37 23.88 23.99 23.72 23.83 23.70 24.20 23.84 23.92 23.97 23.90 23.90 23.91 23.90 23.43 23.86 23.93 23.79 24.29 24.19 24.02 23.79 23.70 23.94 23.68 23.91 24.12 24.03 23.84  CaO 4.97 4.71 4.72 4.76 4.97 5.30 5.72 5.40 5.50 5.71 5.71 5.37 5.16 5.53 5.40 5.58 5.44 5.24 5.21 5.57 5.51 5.64 5.62 5.52 5.60 5.57 5.70 5.45 5.43 5.38 5.60 5.75 5.57  Na2O 7.77 8.02 8.15 8.11 7.62 7.62 7.72 8.00 7.56 7.63 8.06 7.94 7.69 7.75 7.69 7.59 7.70 7.72 7.52 7.85 7.81 7.75 7.80 7.93 7.94 7.83 7.74 7.81 7.89 7.71 7.64 7.50 7.77  K2O 0.79 0.72 0.76 0.75 0.79 0.71 0.65 0.68 0.76 0.69 0.70 0.64 0.73 0.72 0.69 0.65 0.69 0.82 0.73 0.62 0.73 0.75 0.69 0.75 0.72 0.76 0.65 0.74 0.74 0.70 0.60 0.64 0.70  MgO 0.00 0.01 0.01 0.02 0.02 0.00 0.01 0.05 0.01 0.02 0.00 0.01 0.00 0.00 0.02 0.00 0.00 0.00 0.03 0.01 0.00 0.02 0.01 0.03 0.00 0.00 0.00 0.01 0.02 0.00 0.00 0.00 0.01  MnO 0.02 0.00 0.02 0.03 0.00 0.00 0.00 0.02 0.01 0.05 0.00 0.01 0.02 0.00 0.02 0.00 0.02 0.04 0.00 0.01 0.00 0.05 0.01 0.02 0.00 0.00 0.00 0.04 0.01 0.04 0.00 0.00 0.00  FeO 0.22 0.12 0.29 0.16 0.22 0.19 0.24 0.06 0.18 0.24 0.32 0.20 0.18 0.19 0.17 0.13 0.18 0.18 0.22 0.29 0.14 0.25 0.18 0.12 0.19 0.22 0.20 0.38 0.18 0.13 0.09 0.15 0.31  117  Total 100.15 100.42 100.95 100.40 100.22 100.04 101.04 100.76 100.53 100.27 101.53 100.49 100.38 100.83 100.72 100.65 101.10 100.69 100.50 101.02 100.97 101.18 101.49 101.66 100.75 100.72 100.74 100.46 101.25 100.16 99.94 100.68 100.83  mol frac An 0.249 0.235 0.232 0.234 0.252 0.266 0.280 0.261 0.274 0.281 0.270 0.262 0.259 0.271 0.268 0.278 0.269 0.260 0.265 0.272 0.269 0.274 0.273 0.266 0.269 0.270 0.278 0.266 0.264 0.267 0.278 0.286 0.272  mol frac Ab 0.704 0.723 0.724 0.722 0.700 0.692 0.683 0.700 0.681 0.679 0.690 0.701 0.698 0.687 0.691 0.684 0.690 0.692 0.691 0.693 0.689 0.682 0.687 0.691 0.690 0.686 0.684 0.691 0.694 0.692 0.687 0.676 0.687  mol frac Or 0.047 0.043 0.044 0.044 0.048 0.042 0.038 0.039 0.045 0.040 0.039 0.037 0.044 0.042 0.041 0.039 0.041 0.048 0.044 0.036 0.042 0.043 0.040 0.043 0.041 0.044 0.038 0.043 0.043 0.041 0.036 0.038 0.041  Table A3 continued. Electron microprobe analysis data Label 7-5-405-2_55 7-5-405-2_56 7-5-405-2_57 7-5-405-2_58 7-5-405-2_59 7-5-405-2_60  SiO2 62.48 62.48 62.61 62.65 62.24 63.20  Al2O3 24.03 23.77 23.60 23.90 23.87 23.92  CaO 5.65 5.67 5.68 5.59 5.57 5.55  Na2O 7.94 7.60 7.81 7.66 7.80 7.99  K2O 0.70 0.67 0.66 0.59 0.72 0.79  MgO 0.00 0.00 0.01 0.01 0.01 0.02  MnO 0.00 0.00 0.00 0.00 0.00 0.01  FeO 0.09 0.13 0.17 0.22 0.18 0.19  Total 100.89 100.32 100.54 100.62 100.40 101.66  mol frac An 0.271 0.280 0.276 0.277 0.271 0.265  mol frac Ab 0.689 0.680 0.686 0.688 0.687 0.690  mol frac Or 0.040 0.040 0.038 0.035 0.042 0.045  7-5-410-1 7-5-410-2 7-5-410-3  62.20 62.54 63.28  23.88 24.65 23.58  5.64 6.32 4.88  7.50 7.36 8.05  0.60 0.61 0.74  0.00 0.00 0.01  0.03 0.00 0.05  0.22 0.17 0.23  100.06 101.65 100.82  0.283 0.310 0.240  0.681 0.654 0.717  0.036 0.036 0.043  7-5-411-1 7-5-411-2 7-5-411-3  62.94 58.75 64.33  23.96 26.59 23.06  5.47 8.55 4.52  8.17 6.61 8.48  0.57 0.30 0.74  0.01 0.00 0.03  0.02 0.05 0.00  0.23 0.21 0.02  101.38 101.06 101.18  0.261 0.410 0.218  0.706 0.573 0.740  0.032 0.017 0.043  7-5-412-1 7-5-412-2  59.23 64.14  25.97 22.99  7.59 4.39  6.76 8.39  0.37 0.75  0.04 0.00  0.00 0.04  0.31 0.17  100.26 100.87  0.375 0.215  0.604 0.742  0.022 0.044  7-2-104-1 7-2-104-2  62.31 64.06  24.77 23.39  6.38 4.66  7.69 7.93  0.38 0.62  0.01 0.03  0.05 0.00  0.13 0.00  101.72 100.69  0.308 0.236  0.671 0.727  0.022 0.037  7-2-105-1 7-2-105-2 7-2-105-3  65.28 64.48 63.92  22.54 22.82 22.92  3.83 4.58 4.06  8.77 8.10 8.43  0.89 0.80 0.65  0.00 0.01 0.00  0.00 0.06 0.06  0.16 0.26 0.06  101.48 101.11 100.11  0.185 0.227 0.202  0.765 0.726 0.759  0.051 0.047 0.039  7-1-5901-1 7-1-5901-2  58.08 64.31  27.25 23.44  9.61 4.93  6.13 8.09  0.26 0.64  0.03 0.01  0.00 0.03  0.21 0.22  101.58 101.66  0.457 0.243  0.528 0.720  0.015 0.038  7-1-5905-1 7-1-5905-2  64.12 64.20  23.48 23.53  4.44 4.34  8.27 8.36  0.64 0.65  0.01 0.02  0.00 0.03  0.12 0.17  101.09 101.29  0.220 0.214  0.742 0.747  0.038 0.038  7-4-3505-1 7-4-3505-2  64.67 63.73  23.18 23.40  4.28 4.61  8.35 7.82  0.64 0.72  0.02 0.00  0.02 0.04  0.07 0.26  101.23 100.58  0.212 0.235  0.750 0.721  0.038 0.044  118  Table A3 continued. Electron microprobe analysis data Label 7-4-3508-1 7-4-3508-2 7-4-3508-3  SiO2 56.71 55.91 64.74  Al2O3 28.00 27.88 22.51  CaO 9.86 9.94 3.48  Na2O 5.59 5.65 8.95  K2O 0.27 0.30 0.90  MgO 0.00 0.01 0.00  MnO 0.00 0.06 0.04  FeO 0.18 0.18 0.16  Total 100.60 99.92 100.79  mol frac An 0.486 0.484 0.168  mol frac Ab 0.498 0.498 0.781  mol frac Or 0.016 0.017 0.052  7-4-3512-1_1 7-4-3512-1_2 7-4-3512-1_3 7-4-3512-1_4 7-4-3512-1_5 7-4-3512-1_6 7-4-3512-1_7 7-4-3512-1_8 7-4-3512-1_9 7-4-3512-1_10 7-4-3512-1_11 7-4-3512-1_12 7-4-3512-1_13 7-4-3512-1_14 7-4-3512-1_15 7-4-3512-1_16 7-4-3512-1_17 7-4-3512-1_18 7-4-3512-1_19 7-4-3512-1_20 7-4-3512-1_21 7-4-3512-1_22 7-4-3512-1_23 7-4-3512-1_24 7-4-3512-1_25 7-4-3512-1_26 7-4-3512-1_27 7-4-3512-1_28 7-4-3512-1_29  63.34 64.08 63.86 62.77 62.81 62.65 62.05 63.11 62.51 62.75 62.38 64.30 63.58 62.81 63.78 62.69 63.25 62.99 62.35 62.90 64.31 63.89 63.09 63.64 63.76 63.27 64.72 64.32 63.78  23.88 23.52 23.65 23.61 23.64 23.70 23.80 23.91 24.05 23.81 23.55 23.72 23.99 23.73 23.78 23.61 23.75 23.68 23.69 23.59 23.59 23.59 23.52 23.24 23.39 23.44 23.41 23.46 22.94  5.28 5.10 5.38 5.13 4.74 5.31 5.22 5.10 5.20 5.20 5.12 5.15 5.19 5.02 4.98 5.14 5.06 4.88 5.22 4.89 5.11 5.08 4.80 4.93 4.90 4.63 4.84 4.48 4.43  7.95 8.09 7.98 7.96 8.49 8.03 8.14 7.73 8.21 8.23 7.77 8.12 7.84 7.85 8.22 8.10 8.30 8.15 7.93 7.93 7.91 8.36 8.38 8.10 8.04 8.33 8.59 8.02 8.18  0.60 0.68 0.57 0.62 0.67 0.56 0.63 0.55 0.64 0.68 0.59 0.51 0.69 0.70 0.61 0.58 0.63 0.66 0.73 0.63 0.71 0.70 0.74 0.70 0.62 0.72 0.64 0.70 0.65  0.02 0.02 0.00 0.04 0.01 0.01 0.00 0.00 0.03 0.00 0.00 0.00 0.01 0.01 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.00 0.02 0.00  0.00 0.00 0.08 0.00 0.01 0.01 0.00 0.04 0.00 0.00 0.02 0.00 0.02 0.06 0.02 0.00 0.00 0.05 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.03 0.04 0.00 0.02  0.10 0.19 0.06 0.12 0.11 0.15 0.13 0.13 0.21 0.26 0.23 0.28 0.14 0.05 0.17 0.13 0.15 0.27 0.19 0.09 0.21 0.28 0.12 0.17 0.16 0.17 0.13 0.14 0.10  101.17 101.67 101.58 100.24 100.46 100.41 99.97 100.56 100.84 100.93 99.65 102.08 101.48 100.23 101.56 100.26 101.15 100.67 100.11 100.03 101.86 101.89 100.65 100.80 100.88 100.57 102.37 101.15 100.09  0.259 0.248 0.262 0.253 0.227 0.259 0.252 0.258 0.250 0.249 0.258 0.252 0.257 0.250 0.242 0.251 0.243 0.239 0.255 0.245 0.252 0.241 0.230 0.241 0.243 0.225 0.229 0.226 0.221  0.706 0.712 0.704 0.711 0.735 0.709 0.712 0.709 0.714 0.713 0.707 0.719 0.702 0.708 0.723 0.715 0.721 0.723 0.702 0.718 0.706 0.719 0.728 0.718 0.721 0.733 0.735 0.732 0.740  0.035 0.039 0.033 0.036 0.038 0.033 0.036 0.033 0.037 0.039 0.035 0.030 0.041 0.042 0.035 0.034 0.036 0.039 0.043 0.038 0.042 0.040 0.042 0.041 0.037 0.042 0.036 0.042 0.039  119  Table A3 continued. Electron microprobe analysis data Label 7-4-3512-1_30  SiO2 64.20  Al2O3 22.94  CaO 4.21  Na2O 8.27  K2O 0.76  MgO 0.01  MnO 0.06  FeO 0.14  Total 100.58  mol frac An 0.210  mol frac Ab 0.745  mol frac Or 0.045  7-4-3512-2_1 7-4-3512-2_2 7-4-3512-2_3 7-4-3512-2_4 7-4-3512-2_5 7-4-3512-2_6 7-4-3512-2_7 7-4-3512-2_8 7-4-3512-2_9 7-4-3512-2_10 7-4-3512-2_11 7-4-3512-2_12 7-4-3512-2_13 7-4-3512-2_14 7-4-3512-2_15 7-4-3512-2_16 7-4-3512-2_17 7-4-3512-2_18 7-4-3512-2_19 7-4-3512-2_20 7-4-3512-2_21 7-4-3512-2_22 7-4-3512-2_23 7-4-3512-2_24 7-4-3512-2_25 7-4-3512-2_26 7-4-3512-2_27 7-4-3512-2_28 7-4-3512-2_29 7-4-3512-2_30 7-4-3512-2_31  63.30 62.51 63.71 63.61 63.24 63.40 62.67 62.82 62.62 62.32 62.03 61.77 62.67 62.16 62.98 62.52 63.12 63.78 63.10 61.51 63.64 63.24 63.30 63.41 64.64 63.25 61.84 63.29 62.62 63.08 63.25  23.78 23.72 23.71 23.60 23.92 23.86 23.67 23.86 23.81 24.00 23.74 23.96 23.89 23.35 23.84 23.49 23.78 23.75 23.66 23.75 23.50 23.43 23.43 23.40 23.33 23.15 23.74 23.24 23.43 23.84 23.58  5.21 5.11 5.17 5.12 5.02 5.06 5.18 4.91 5.18 5.17 5.23 5.41 5.35 5.42 5.03 5.24 5.07 4.85 4.98 5.22 5.05 4.74 4.90 4.93 4.77 4.81 5.00 4.90 4.95 4.84 4.81  8.02 7.89 8.10 8.19 8.28 8.16 8.00 8.26 7.93 7.82 7.94 7.80 8.27 7.64 8.30 7.78 8.35 7.93 7.90 8.41 7.99 8.18 8.12 8.05 8.09 8.27 8.16 8.34 8.12 8.40 8.27  0.68 0.54 0.58 0.57 0.60 0.58 0.57 0.63 0.62 0.51 0.60 0.55 0.61 0.61 0.56 0.60 0.67 0.53 0.52 0.63 0.63 0.64 0.61 0.60 0.59 0.58 0.66 0.61 0.62 0.65 0.67  0.01 0.00 0.00 0.02 0.00 0.00 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.00 0.00 0.00 0.02 0.00 0.02 0.01 0.00 0.01 0.01 0.01 0.02 0.04 0.02 0.00 0.02 0.02  0.03 0.00 0.03 0.00 0.00 0.01 0.00 0.02 0.01 0.00 0.02 0.05 0.01 0.01 0.00 0.00 0.05 0.04 0.01 0.00 0.04 0.09 0.03 0.02 0.12 0.00 0.00 0.02 0.03 0.00 0.01  0.17 0.10 0.27 0.18 0.20 0.12 0.15 0.28 0.11 0.12 0.19 0.12 0.17 0.14 0.15 0.18 0.15 0.09 0.04 0.19 0.25 0.08 0.18 0.23 0.01 0.21 0.22 0.27 0.19 0.17 0.19  101.20 99.88 101.56 101.29 101.26 101.20 100.27 100.77 100.27 99.93 99.74 99.65 100.97 99.35 100.86 99.81 101.19 100.98 100.21 99.74 101.11 100.40 100.56 100.65 101.55 100.29 99.67 100.69 99.96 101.01 100.79  0.254 0.255 0.252 0.248 0.242 0.247 0.255 0.238 0.256 0.259 0.258 0.268 0.254 0.271 0.243 0.262 0.242 0.245 0.250 0.246 0.249 0.233 0.241 0.244 0.237 0.235 0.243 0.237 0.243 0.233 0.234  0.707 0.713 0.714 0.719 0.723 0.720 0.712 0.725 0.708 0.710 0.707 0.700 0.711 0.692 0.725 0.703 0.720 0.724 0.719 0.718 0.714 0.729 0.723 0.721 0.728 0.731 0.719 0.728 0.721 0.730 0.727  0.039 0.032 0.034 0.033 0.035 0.034 0.033 0.036 0.036 0.031 0.035 0.033 0.035 0.036 0.032 0.036 0.038 0.032 0.031 0.035 0.037 0.038 0.036 0.035 0.035 0.034 0.038 0.035 0.036 0.037 0.039  120  Table A3 continued. Electron microprobe analysis data Label 7-4-3512-2_32 7-4-3512-2_33 7-4-3512-2_34 7-4-3512-2_35 7-4-3512-2_36 7-4-3512-2_37 7-4-3512-2_38 7-4-3512-2_39 7-4-3512-2_40 7-4-3512-2_41 7-4-3512-2_42 7-4-3512-2_43 7-4-3512-2_44 7-4-3512-2_45 7-4-3512-2_46 7-4-3512-2_47 7-4-3512-2_48 7-4-3512-2_49 7-4-3512-2_50 7-4-3512-2_51 7-4-3512-2_52 7-4-3512-2_53 7-4-3512-2_54 7-4-3512-2_55 7-4-3512-2_56 7-4-3512-2_57 7-4-3512-2_58 7-4-3512-2_59 7-4-3512-2_60 7-4-3512-2_61 7-4-3512-2_62 7-4-3512-2_63 7-4-3512-2_64  SiO2 63.81 62.88 63.72 62.58 64.26 62.92 63.12 63.47 63.18 61.69 63.46 63.14 62.51 62.95 63.01 63.35 63.38 63.76 63.27 63.50 62.57 63.74 62.84 62.52 63.34 63.26 62.98 64.13 63.36 63.37 63.24 62.99 64.04  Al2O3 23.71 23.39 23.49 23.82 23.85 23.82 23.66 23.98 24.07 23.71 23.81 23.23 23.34 23.45 23.71 23.51 23.51 23.76 23.57 23.12 23.61 23.75 23.74 23.75 23.48 23.42 23.42 23.29 23.78 23.77 23.43 22.96 23.22  CaO 5.11 4.78 4.88 4.96 5.15 5.22 5.26 5.46 5.22 5.30 5.34 5.05 5.05 4.94 5.13 5.01 5.49 5.03 5.00 4.95 4.96 5.02 4.97 5.22 4.76 5.07 4.92 4.96 4.89 4.84 4.91 4.73 4.67  Na2O 8.51 8.31 8.42 8.05 7.88 8.24 8.40 7.88 8.22 7.94 7.84 7.97 8.26 8.04 8.04 7.96 8.15 8.14 7.95 7.99 8.07 8.07 8.19 8.50 8.07 8.23 8.04 7.90 8.15 8.34 8.12 8.43 8.33  K2O 0.63 0.61 0.61 0.69 0.62 0.66 0.68 0.52 0.64 0.62 0.61 0.60 0.56 0.60 0.60 0.61 0.64 0.50 0.60 0.67 0.67 0.65 0.65 0.59 0.60 0.67 0.68 0.66 0.60 0.64 0.64 0.68 0.61  MgO 0.00 0.01 0.00 0.01 0.01 0.03 0.00 0.00 0.02 0.02 0.01 0.04 0.00 0.02 0.01 0.00 0.01 0.01 0.00 0.03 0.02 0.00 0.00 0.00 0.01 0.01 0.00 0.00 0.03 0.00 0.01 0.00 0.00  MnO 0.00 0.05 0.04 0.09 0.00 0.00 0.03 0.02 0.06 0.02 0.03 0.00 0.01 0.01 0.03 0.00 0.02 0.01 0.03 0.00 0.00 0.00 0.03 0.04 0.02 0.01 0.00 0.09 0.01 0.00 0.00 0.05 0.02  FeO 0.20 0.15 0.09 0.18 0.22 0.22 0.23 0.20 0.19 0.10 0.18 0.20 0.10 0.08 0.17 0.21 0.27 0.17 0.19 0.13 0.11 0.24 0.21 0.10 0.11 0.09 0.19 0.18 0.15 0.21 0.06 0.16 0.20  121  Total 101.97 100.17 101.25 100.37 101.98 101.10 101.39 101.51 101.59 99.41 101.28 100.22 99.82 100.08 100.70 100.64 101.47 101.38 100.62 100.39 100.01 101.48 100.65 100.73 100.40 100.75 100.23 101.20 100.97 101.16 100.42 99.99 101.10  mol frac An 0.240 0.233 0.234 0.244 0.256 0.250 0.247 0.269 0.250 0.260 0.264 0.250 0.244 0.245 0.252 0.249 0.261 0.247 0.249 0.245 0.244 0.246 0.242 0.245 0.237 0.244 0.243 0.248 0.240 0.234 0.241 0.228 0.228  mol frac Ab 0.724 0.732 0.731 0.716 0.708 0.713 0.715 0.701 0.713 0.704 0.701 0.715 0.723 0.720 0.713 0.715 0.702 0.724 0.716 0.716 0.717 0.716 0.721 0.722 0.727 0.717 0.718 0.713 0.725 0.729 0.722 0.734 0.736  mol frac Or 0.035 0.035 0.035 0.040 0.037 0.038 0.038 0.030 0.037 0.036 0.036 0.035 0.032 0.035 0.035 0.036 0.036 0.029 0.036 0.040 0.039 0.038 0.038 0.033 0.036 0.038 0.040 0.039 0.035 0.037 0.037 0.039 0.036  Table A3 continued. Electron microprobe analysis data Label  SiO2  Al2O3  CaO  Na2O  K2O  MgO  MnO  FeO  Total  mol frac An  mol frac Ab  7-4-3512-2_65 7-4-3512-2_66 7-4-3512-2_67 7-4-3512-2_68 7-4-3512-2_69 7-4-3512-2_70  63.55 64.32 63.48 65.06 64.13 64.07  23.40 23.07 23.31 22.85 22.97 23.15  4.49 4.48 4.34 4.27 4.15 4.23  8.18 8.33 8.70 8.54 8.45 8.67  0.66 0.60 0.74 0.71 0.73 0.75  0.00 0.00 0.00 0.00 0.00 0.00  0.00 0.00 0.04 0.00 0.01 0.01  0.21 0.05 0.21 0.13 0.24 0.32  100.48 100.85 100.82 101.56 100.68 101.18  0.224 0.221 0.207 0.208 0.204 0.203  0.737 0.744 0.751 0.751 0.753 0.754  mol frac Or 0.039 0.035 0.042 0.041 0.043 0.043  7-4-3514-1 7-4-3514-2 7-4-3514-3  57.91 52.82 53.34  27.33 30.10 30.21  9.48 12.95 12.94  6.12 4.10 3.97  0.21 0.15 0.11  0.00 0.00 0.01  0.00 0.00 0.02  0.27 0.22 0.18  101.32 100.34 100.78  0.456 0.630 0.639  0.532 0.361 0.355  0.012 0.009 0.007  7-4-3515-1 7-4-3515-2 7-4-3515-3 7-4-3516_1 7-4-3516_2 7-4-3516_3 7-4-3516_4 7-4-3516_5 7-4-3516_6 7-4-3516_7 7-4-3516_8 7-4-3516_9 7-4-3516_10 7-4-3516_11 7-4-3516_12 7-4-3516_13 7-4-3516_14 7-4-3516_15 7-4-3516_16 7-4-3516_17 7-4-3516_18  62.28 60.92 60.84 57.57 57.14 57.26 57.59 58.27 58.77 60.15 61.08 61.72 63.73 64.77 63.45 64.39 65.48 64.16 64.41 65.36  24.64 25.18 25.43 27.90 27.57 27.59 27.20 27.36 26.22 25.68 25.76 24.37 23.20 22.99 23.08 22.85 22.69 22.64 22.62 22.52  6.05 6.97 7.17 9.69 9.75 9.34 8.75 8.98 8.03 6.82 7.03 6.14 4.57 4.04 4.25 4.28 3.82 3.83 3.79 3.91  7.93 7.26 6.96 5.70 5.86 6.08 6.10 6.11 6.72 7.09 7.07 7.47 8.32 8.54 8.31 8.47 8.47 8.54 8.68 8.57  0.57 0.56 0.53 0.26 0.33 0.27 0.29 0.27 0.39 0.43 0.43 0.48 0.79 0.78 0.82 0.84 0.85 0.89 0.83 0.81  0.00 0.00 0.00 0.00 0.00 0.01 0.03 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.01 0.01 0.00 0.00  0.00 0.00 0.04 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.00 0.01 0.01 0.03 0.00 0.00 0.00 0.00 0.03  0.19 0.22 0.17 0.23 0.30 0.26 0.20 0.22 0.28 0.22 0.23 0.03 0.15 0.15 0.08 0.18 0.03 0.04 0.17 0.09  101.67 101.11 101.15 101.34 100.95 100.82 100.16 101.23 100.41 100.39 101.63 100.20 100.77 101.28 100.02 101.02 101.34 100.09 100.51 101.29  0.287 0.336 0.352 0.477 0.470 0.452 0.435 0.441 0.389 0.338 0.346 0.304 0.222 0.198 0.210 0.208 0.190 0.188 0.185 0.192  0.681 0.632 0.618 0.508 0.511 0.532 0.548 0.543 0.589 0.636 0.629 0.668 0.732 0.757 0.742 0.744 0.760 0.760 0.767 0.761  0.032 0.032 0.031 0.015 0.019 0.016 0.017 0.016 0.023 0.025 0.025 0.028 0.046 0.046 0.048 0.049 0.050 0.052 0.048 0.047  122  Table A3 continued. Electron microprobe analysis data Label 7-4-3516_19 7-4-3516_20 7-4-3516_21 7-4-3516_22 7-4-3516_23 7-4-3516_24 7-4-3516_25 7-4-3516_26 7-4-3516_27 7-4-3516_28 7-4-3516_29  SiO2 65.51 64.06 63.98 63.61 64.48 65.77 65.40 66.21 65.30 65.97 64.43  Al2O3 22.58 22.34 22.81 22.83 22.62 22.35 22.36 22.00 22.15 22.18 22.28  CaO 3.66 3.57 3.95 4.03 3.85 3.48 3.27 3.36 3.32 3.42 3.70  Na2O 8.73 8.59 8.69 8.70 8.60 8.55 8.68 8.86 8.73 8.88 8.30  K2O 0.85 0.87 0.81 0.87 0.86 0.90 0.97 0.97 1.00 0.90 0.89  MgO 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.02 0.00  MnO 0.00 0.00 0.03 0.00 0.00 0.02 0.02 0.00 0.02 0.00 0.03  FeO 0.21 0.07 0.07 0.09 0.10 0.13 0.18 0.09 0.20 0.05 0.08  Total 101.56 99.50 100.34 100.13 100.52 101.20 100.88 101.49 100.71 101.42 99.72  mol frac An 0.179 0.177 0.191 0.194 0.188 0.174 0.162 0.164 0.164 0.166 0.187  mol frac Ab 0.772 0.771 0.762 0.757 0.762 0.773 0.780 0.780 0.778 0.782 0.759  mol frac Or 0.049 0.051 0.047 0.050 0.050 0.054 0.057 0.056 0.059 0.052 0.054  7-2-102-1_1 7-2-102-1_2 7-2-102-1_3 7-2-102-1_4 7-2-102-1_5 7-2-102-1_6 7-2-102-1_7 7-2-102-1_8 7-2-102-1_9 7-2-102-1_10 7-2-102-1_11 7-2-102-1_12 7-2-102-1_13 7-2-102-1_14 7-2-102-1_15 7-2-102-1_16 7-2-102-1_17 7-2-102-1_18 7-2-102-1_19 7-2-102-1_20 7-2-102-1_21  56.95 58.83 58.34 58.53 58.17 58.92 59.65 58.60 58.05 58.69 58.24 59.30 59.42 58.87 59.45 59.73 60.84 59.91 59.57 60.03 60.25  26.43 26.48 26.31 26.36 26.62 26.32 26.51 26.49 26.07 26.08 25.81 25.94 25.87 26.06 25.77 25.72 25.35 25.46 25.32 25.20 25.46  8.46 8.30 8.41 8.40 8.44 7.95 8.13 8.04 8.14 7.87 7.93 7.54 7.80 7.83 7.66 7.15 6.68 6.92 6.98 6.87 6.68  6.37 6.39 6.46 6.38 6.34 6.43 6.41 6.45 6.73 6.61 6.79 6.95 6.75 6.72 6.84 7.09 7.31 7.09 7.08 7.13 7.25  0.28 0.27 0.37 0.33 0.31 0.25 0.23 0.30 0.35 0.29 0.40 0.28 0.34 0.32 0.37 0.34 0.34 0.37 0.41 0.38 0.40  0.02 0.03 0.04 0.03 0.02 0.03 0.02 0.02 0.02 0.00 0.04 0.01 0.01 0.03 0.02 0.02 0.04 0.02 0.03 0.01 0.00  0.00 0.00 0.00 0.00 0.02 0.02 0.00 0.03 0.00 0.00 0.00 0.05 0.02 0.00 0.06 0.02 0.01 0.01 0.00 0.02 0.09  0.37 0.57 0.32 0.40 0.33 0.29 0.44 0.46 0.40 0.25 0.30 0.33 0.29 0.18 0.30 0.38 0.32 0.28 0.24 0.23 0.14  98.89 100.87 100.26 100.41 100.25 100.20 101.38 100.39 99.76 99.78 99.52 100.41 100.49 100.01 100.48 100.43 100.89 100.07 99.61 99.87 100.27  0.416 0.411 0.409 0.413 0.416 0.400 0.406 0.401 0.393 0.390 0.383 0.369 0.382 0.384 0.374 0.351 0.329 0.343 0.344 0.340 0.330  0.567 0.573 0.569 0.568 0.566 0.585 0.580 0.582 0.587 0.593 0.594 0.615 0.598 0.597 0.604 0.629 0.651 0.635 0.632 0.638 0.647  0.016 0.016 0.021 0.019 0.018 0.015 0.014 0.018 0.020 0.017 0.023 0.016 0.020 0.019 0.022 0.020 0.020 0.022 0.024 0.022 0.024  123  Table A3 continued. Electron microprobe analysis data Label 7-2-102-1_22 7-2-102-1_23 7-2-102-1_24 7-2-102-1_25 7-2-102-1_26 7-2-102-1_27 7-2-102-1_28 7-2-102-1_29 7-2-102-1_30 7-2-102-1_31 7-2-102-1_32 7-2-102-1_33 7-2-102-1_34 7-2-102-1_35 7-2-102-1_36 7-2-102-1_37 7-2-102-1_38 7-2-102-1_39  SiO2 60.51 60.90 60.58 61.13 60.63 60.80 61.68 61.28 61.42 61.75 61.69 62.10 61.31 60.87 61.81 63.70 63.95 64.44  Al2O3 24.80 25.13 24.98 24.89 24.50 24.73 24.55 23.97 24.59 24.06 23.78 24.70 24.76 24.44 24.06 23.17 22.84 22.79  CaO 6.65 6.62 6.40 6.44 6.25 6.19 6.00 5.89 5.82 5.61 5.47 5.92 6.18 5.99 5.36 4.57 4.30 4.16  Na2O 7.15 7.46 7.19 7.72 7.63 7.43 7.66 7.50 7.67 7.75 7.67 7.67 7.45 7.58 7.79 8.28 8.34 8.33  K2O 0.40 0.35 0.41 0.47 0.45 0.47 0.54 0.54 0.49 0.49 0.52 0.49 0.43 0.45 0.50 0.60 0.65 0.70  MgO 0.03 0.00 0.01 0.01 0.05 0.00 0.00 0.00 0.03 0.00 0.02 0.00 0.00 0.00 0.00 0.02 0.00 0.01  MnO 0.01 0.01 0.00 0.00 0.01 0.02 0.00 0.00 0.04 0.00 0.02 0.00 0.00 0.01 0.00 0.07 0.03 0.00  FeO 0.32 0.17 0.21 0.15 0.16 0.17 0.27 0.16 0.29 0.23 0.26 0.18 0.17 0.06 0.23 0.15 0.20 0.22  Total 99.87 100.65 99.77 100.81 99.68 99.82 100.69 99.33 100.35 99.88 99.44 101.06 100.29 99.41 99.74 100.55 100.31 100.64  mol frac An 0.331 0.322 0.322 0.307 0.304 0.307 0.293 0.293 0.287 0.278 0.274 0.290 0.306 0.296 0.267 0.226 0.213 0.207  mol frac Ab 0.645 0.657 0.654 0.666 0.671 0.666 0.676 0.675 0.684 0.694 0.695 0.681 0.668 0.678 0.703 0.739 0.748 0.751  mol frac Or 0.024 0.020 0.025 0.027 0.026 0.028 0.031 0.032 0.029 0.029 0.031 0.029 0.025 0.027 0.030 0.035 0.038 0.042  7-2-102-2_1 7-2-102-2_2 7-2-102-2_3 7-2-102-2_4 7-2-102-2_5 7-2-102-2_6 7-2-102-2_7 7-2-102-2_8 7-2-102-2_9 7-2-102-2_10 7-2-102-2_11 7-2-102-2_12 7-2-102-2_13 7-2-102-2_14  57.73 58.37 57.90 58.52 59.54 58.93 58.66 59.89 59.48 58.26 59.21 58.30 58.90 59.27  27.19 26.71 26.81 26.86 26.51 26.20 26.56 26.42 26.62 26.32 26.57 26.36 26.42 26.49  8.72 8.77 8.59 8.57 8.46 8.46 8.46 8.36 8.15 8.45 8.45 8.19 8.36 8.40  6.21 6.25 6.29 6.35 6.43 6.30 6.34 6.34 6.55 6.45 6.60 6.62 6.20 6.65  0.27 0.28 0.34 0.27 0.31 0.26 0.25 0.22 0.33 0.24 0.23 0.31 0.26 0.29  0.02 0.04 0.01 0.02 0.06 0.00 0.03 0.00 0.03 0.01 0.01 0.02 0.01 0.00  0.01 0.00 0.01 0.00 0.00 0.07 0.03 0.01 0.00 0.00 0.00 0.00 0.03 0.00  0.44 0.17 0.47 0.29 0.44 0.35 0.28 0.29 0.40 0.31 0.29 0.39 0.29 0.33  100.59 100.59 100.43 100.89 101.74 100.57 100.61 101.53 101.57 100.04 101.35 100.19 100.46 101.42  0.430 0.430 0.422 0.421 0.413 0.419 0.418 0.416 0.400 0.414 0.409 0.399 0.420 0.404  0.554 0.554 0.559 0.564 0.569 0.565 0.567 0.571 0.581 0.572 0.578 0.583 0.564 0.579  0.016 0.016 0.020 0.016 0.018 0.015 0.015 0.013 0.019 0.014 0.013 0.018 0.016 0.017  124  Table A3 continued. Electron microprobe analysis data Label 7-2-102-2_15 7-2-102-2_16 7-2-102-2_17 7-2-102-2_18 7-2-102-2_19 7-2-102-2_20 7-2-102-2_21 7-2-102-2_22 7-2-102-2_23 7-2-102-2_24 7-2-102-2_25 7-2-102-2_26 7-2-102-2_27 7-2-102-2_28 7-2-102-2_29 7-2-102-2_30 7-2-102-2_31 7-2-102-2_32 7-2-102-2_33 7-2-102-2_34 7-2-102-2_35 7-2-102-2_36 7-2-102-2_37 7-2-102-2_38 7-2-102-2_39 7-2-102-2_40 7-2-102-2_41 7-2-102-2_42 7-2-102-2_43 7-2-102-2_44 7-2-102-2_45 7-2-102-2_46 7-2-102-2_47  SiO2 59.34 58.63 59.28 58.27 59.03 58.63 58.02 58.75 57.96 58.65 57.90 57.79 58.12 57.97 58.62 59.13 59.13 59.58 58.57 58.32 58.87 58.41 59.77 59.76 59.89 59.73 59.70 59.26 59.48 59.07 59.12  Al2O3 26.55 26.34 26.45 26.92 26.63 26.45 26.14 26.52 26.18 26.20 26.37 26.42 26.42 26.21 26.18 26.45 26.11 25.77 26.31 26.11 26.13 26.13 25.75 26.00 26.15 25.85 26.11 26.19 26.13 26.18 26.03  CaO 8.60 8.42 8.33 8.11 8.42 8.12 8.55 8.24 7.96 7.68 8.20 7.91 8.07 8.15 8.21 8.06 8.06 8.23 7.86 7.90 7.78 7.73 7.78 7.79 7.66 7.72 7.93 7.84 7.79 7.90 8.20  Na2O 6.32 6.23 6.43 6.32 6.40 6.50 6.36 6.44 6.69 6.51 6.48 6.31 6.58 6.67 6.73 6.69 7.04 6.99 6.58 6.70 6.66 6.56 6.76 6.92 6.73 6.85 6.68 6.45 6.72 6.36 6.68  K2O 0.23 0.30 0.28 0.24 0.30 0.34 0.31 0.30 0.33 0.25 0.27 0.32 0.31 0.33 0.33 0.32 0.32 0.31 0.25 0.29 0.28 0.36 0.28 0.27 0.35 0.29 0.29 0.28 0.30 0.35 0.36  MgO 0.02 0.03 0.05 0.00 0.00 0.00 0.01 0.01 0.00 0.00 0.03 0.02 0.00 0.01 0.00 0.02 0.02 0.00 0.00 0.01 0.06 0.00 0.00 0.00 0.02 0.01 0.00 0.02 0.00 0.01 0.00  MnO 0.00 0.03 0.00 0.00 0.00 0.00 0.00 0.06 0.00 0.01 0.00 0.00 0.03 0.00 0.00 0.00 0.00 0.06 0.00 0.06 0.00 0.00 0.05 0.01 0.00 0.01 0.00 0.00 0.00 0.00 0.02  FeO 0.28 0.31 0.32 0.32 0.37 0.47 0.36 0.21 0.25 0.17 0.20 0.33 0.32 0.35 0.25 0.30 0.29 0.31 0.44 0.29 0.26 0.33 0.28 0.31 0.41 0.31 0.31 0.36 0.32 0.34 0.18  125  Total 101.33 100.28 101.13 100.19 101.15 100.53 99.75 100.52 99.37 99.47 99.44 99.10 99.85 99.68 100.33 100.96 100.96 101.25 100.02 99.68 100.03 99.53 100.67 101.06 101.20 100.78 101.02 100.40 100.74 100.21 100.59  mol frac An 0.423 0.420 0.410 0.409 0.414 0.400 0.419 0.407 0.389 0.389 0.405 0.401 0.397 0.395 0.395 0.392 0.381 0.387 0.392 0.388 0.386 0.386 0.382 0.378 0.378 0.377 0.389 0.395 0.384 0.399 0.396  mol frac Ab 0.563 0.562 0.573 0.577 0.569 0.580 0.563 0.576 0.592 0.596 0.579 0.579 0.585 0.586 0.586 0.589 0.602 0.595 0.593 0.595 0.598 0.593 0.601 0.607 0.601 0.606 0.594 0.588 0.599 0.581 0.584  mol frac Or 0.014 0.018 0.016 0.014 0.018 0.020 0.018 0.018 0.019 0.015 0.016 0.019 0.018 0.019 0.019 0.019 0.018 0.017 0.015 0.017 0.017 0.021 0.016 0.016 0.021 0.017 0.017 0.017 0.018 0.021 0.021  Table A3 continued. Electron microprobe analysis data Label 7-2-102-2_48 7-2-102-2_49 7-2-102-2_50 7-2-102-2_51 7-2-102-2_52 7-2-102-2_53 7-2-102-2_54 7-2-102-2_55 7-2-102-2_56 7-2-102-2_57 7-2-102-2_58 7-2-102-2_59 7-2-102-2_60 7-2-102-2_61 7-2-102-2_62 7-2-102-2_63 7-2-102-2_64 7-2-102-2_65 7-2-102-2_66 7-2-102-2_67 7-2-102-2_68 7-2-102-2_69 7-2-102-2_70 7-2-102-2_71 7-2-102-2_72 7-2-102-2_73 7-2-102-2_74 7-2-102-2_75 7-2-102-2_76 7-2-102-2_77 7-2-102-2_78 7-2-102-2_79 7-2-102-2_80  SiO2 57.50 58.90 58.44 58.91 58.91 58.92 58.66 58.98 58.76 59.31 59.61 60.23 59.43 59.84 59.65 59.40 59.67 59.11 59.62 59.96 60.14 60.34 59.67 59.41 59.85 59.67 60.34 60.16 59.75 60.90 59.56 60.55 60.15  Al2O3 25.95 25.86 25.78 25.95 25.84 25.76 25.83 25.84 25.73 25.69 25.72 25.71 25.43 25.82 25.34 25.48 25.36 25.64 25.60 25.43 25.30 25.25 25.47 25.49 25.34 25.27 25.16 25.02 24.90 25.01 25.45 25.29 25.01  CaO 8.03 7.44 7.75 7.86 7.46 7.59 7.69 7.25 7.43 7.32 7.41 7.34 7.41 7.26 7.11 7.40 7.19 7.22 7.22 7.09 7.02 7.19 7.11 6.92 6.79 6.72 6.82 6.39 6.65 6.56 6.71 6.92 6.82  Na2O 6.66 6.89 6.80 6.75 6.90 6.97 6.77 6.86 6.92 7.04 6.94 6.91 7.09 7.12 7.08 7.05 6.99 6.83 7.27 7.20 7.43 6.92 6.96 7.18 7.17 7.29 7.29 7.59 6.80 7.48 7.45 7.08 7.24  K2O 0.33 0.28 0.28 0.32 0.32 0.32 0.29 0.33 0.39 0.35 0.33 0.37 0.35 0.28 0.35 0.32 0.36 0.35 0.36 0.38 0.38 0.37 0.37 0.41 0.43 0.45 0.39 0.39 0.39 0.41 0.42 0.37 0.34  MgO 0.00 0.02 0.04 0.00 0.00 0.01 0.02 0.03 0.01 0.01 0.03 0.03 0.03 0.00 0.03 0.05 0.00 0.00 0.02 0.02 0.03 0.00 0.00 0.03 0.02 0.02 0.03 0.00 0.02 0.02 0.02 0.02 0.00  MnO 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.06 0.00 0.00 0.00 0.01 0.09 0.09 0.00 0.02 0.06 0.00 0.00 0.05 0.02 0.00 0.00 0.01 0.07 0.00 0.00 0.00 0.00 0.05 0.03 0.01 0.00  FeO 0.26 0.24 0.43 0.39 0.22 0.31 0.30 0.23 0.22 0.21 0.27 0.19 0.17 0.17 0.37 0.16 0.44 0.18 0.24 0.21 0.26 0.22 0.11 0.26 0.17 0.27 0.27 0.18 0.31 0.28 0.23 0.17 0.23  126  Total 98.75 99.64 99.52 100.17 99.64 99.86 99.57 99.59 99.47 99.93 100.32 100.78 99.99 100.59 99.92 99.89 100.07 99.33 100.34 100.35 100.58 100.29 99.69 99.72 99.84 99.70 100.29 99.73 98.81 100.72 99.87 100.42 99.79  mol frac An 0.392 0.368 0.380 0.384 0.367 0.369 0.379 0.362 0.364 0.358 0.364 0.362 0.359 0.355 0.350 0.360 0.355 0.361 0.347 0.345 0.336 0.357 0.353 0.339 0.335 0.329 0.333 0.310 0.342 0.319 0.324 0.343 0.336  mol frac Ab 0.589 0.616 0.604 0.597 0.614 0.613 0.604 0.619 0.613 0.622 0.617 0.616 0.621 0.629 0.630 0.621 0.624 0.618 0.632 0.633 0.643 0.621 0.625 0.637 0.640 0.645 0.644 0.667 0.634 0.658 0.652 0.635 0.645  mol frac Or 0.019 0.017 0.016 0.019 0.019 0.019 0.017 0.020 0.023 0.020 0.019 0.022 0.020 0.016 0.021 0.019 0.021 0.021 0.021 0.022 0.022 0.022 0.022 0.024 0.025 0.026 0.023 0.023 0.024 0.024 0.024 0.022 0.020  Table A3 continued. Electron microprobe analysis data Label 7-2-102-2_81 7-2-102-2_82 7-2-102-2_83 7-2-102-2_84 7-2-102-2_85 7-2-102-2_86 7-2-102-2_87 7-2-102-2_88 7-2-102-2_89 7-2-102-2_90  SiO2 61.06 61.36 61.32 60.79 60.76 61.02 60.77 60.78 61.56  Al2O3 25.12 25.41 25.12 25.14 24.89 24.86 24.60 24.57 24.74  CaO 6.87 6.66 6.62 6.60 6.47 6.54 6.07 5.97 5.99  Na2O 7.11 6.97 7.34 7.47 7.34 7.44 7.33 7.52 7.67  K2O 0.44 0.38 0.41 0.41 0.48 0.41 0.48 0.48 0.46  MgO 0.01 0.01 0.02 0.00 0.00 0.02 0.00 0.02 0.00  MnO 0.00 0.03 0.00 0.06 0.00 0.00 0.00 0.00 0.03  FeO 0.15 0.18 0.03 0.24 0.26 0.34 0.12 0.16 0.00  Total 100.77 101.00 100.86 100.70 100.20 100.64 99.37 99.50 100.45  mol frac An 0.339 0.338 0.325 0.320 0.318 0.319 0.305 0.296 0.293  mol frac Ab 0.635 0.639 0.651 0.656 0.654 0.657 0.666 0.675 0.680  mol frac Or 0.026 0.023 0.024 0.024 0.028 0.024 0.029 0.028 0.027  7-1-5902-1_1 7-1-5902-1_2 7-1-5902-1_3 7-1-5902-1_4 7-1-5902-1_5 7-1-5902-1_6 7-1-5902-1_7 7-1-5902-1_8 7-1-5902-1_9 7-1-5902-1_10 7-1-5902-1_11 7-1-5902-1_12 7-1-5902-1_13 7-1-5902-1_14 7-1-5902-1_15 7-1-5902-1_16 7-1-5902-1_17 7-1-5902-1_18 7-1-5902-1_19 7-1-5902-1_20 7-1-5902-1_21 7-1-5902-1_22  61.09 61.31 61.54 61.85 61.57 61.81 61.80 60.87 61.03 59.85 60.42 59.85 59.15 60.01 61.17 60.51 60.43 61.56 60.59 60.75 60.99 61.45  24.70 25.23 24.50 24.36 24.31 24.19 24.27 24.35 24.37 25.15 25.24 25.15 26.20 25.46 24.70 24.86 24.64 24.73 24.52 24.43 24.37 24.77  6.59 6.52 6.10 5.89 5.76 5.61 5.70 5.97 6.02 6.64 6.98 6.78 8.21 6.91 6.27 6.31 6.56 6.45 6.67 6.45 6.53 6.35  7.15 7.28 7.51 7.40 7.90 7.78 7.70 8.00 7.74 7.08 7.11 7.28 6.66 7.06 7.36 7.19 7.81 7.50 7.17 7.28 7.48 7.31  0.47 0.52 0.55 0.57 0.53 0.62 0.62 0.56 0.57 0.46 0.50 0.39 0.41 0.47 0.48 0.54 0.47 0.53 0.48 0.55 0.59 0.55  0.01 0.01 0.00 0.00 0.02 0.00 0.00 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.02 0.00 0.02 0.02 0.00 0.02  0.05 0.00 0.00 0.00 0.00 0.00 0.01 0.06 0.04 0.00 0.03 0.06 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00  0.27 0.16 0.29 0.09 0.10 0.25 0.26 0.20 0.26 0.25 0.31 0.25 0.21 0.34 0.29 0.19 0.33 0.15 0.12 0.22 0.16 0.22  100.33 101.02 100.48 100.16 100.20 100.26 100.36 100.03 100.04 99.42 100.59 99.77 100.84 100.25 100.28 99.61 100.25 100.92 99.57 99.68 100.12 100.67  0.328 0.321 0.300 0.295 0.278 0.275 0.280 0.283 0.291 0.332 0.342 0.332 0.396 0.341 0.311 0.316 0.309 0.312 0.330 0.318 0.314 0.314  0.644 0.649 0.668 0.671 0.691 0.689 0.684 0.686 0.677 0.641 0.629 0.645 0.581 0.631 0.661 0.652 0.665 0.657 0.642 0.650 0.652 0.654  0.028 0.031 0.032 0.034 0.031 0.036 0.036 0.032 0.033 0.027 0.029 0.023 0.024 0.028 0.028 0.032 0.026 0.031 0.028 0.032 0.034 0.032  127  Table A3 continued. Electron microprobe analysis data Label 7-1-5902-1_23 7-1-5902-1_24 7-1-5902-1_25 7-1-5902-1_26 7-1-5902-1_27 7-1-5902-1_28 7-1-5902-1_29 7-1-5902-1_30 7-1-5902-1_31 7-1-5902-1_32 7-1-5902-1_33 7-1-5902-1_34 7-1-5902-1_35 7-1-5902-1_36 7-1-5902-1_37 7-1-5902-1_38 7-1-5902-1_39 7-1-5902-1_40 7-1-5902-1_41 7-1-5902-1_42 7-1-5902-1_43 7-1-5902-1_44 7-1-5902-1_45 7-1-5902-1_46 7-1-5902-1_47 7-1-5902-1_48 7-1-5902-1_49 7-1-5902-1_50  SiO2 61.05 61.67 61.33 61.07 59.97 62.44 61.83 63.60 62.20 63.49 63.05 62.21 61.86 61.46 61.57 61.93 61.93 60.01 60.42 64.91 61.47 62.00 61.02 61.07 60.49 61.39 60.24 60.71  Al2O3 24.48 24.63 24.49 24.62 24.56 24.13 24.53 24.07 24.12 24.23 24.66 24.85 24.51 24.37 24.82 25.09 24.92 25.21 25.15 22.91 25.03 24.69 24.72 25.31 25.33 25.07 25.30 25.07  CaO 6.13 6.20 6.24 6.28 5.95 6.00 5.89 6.18 5.75 5.73 6.05 6.05 6.04 6.15 6.39 6.63 6.49 6.38 7.06 5.66 6.53 6.54 6.36 7.04 7.07 6.82 6.94 6.64  Na2O 7.23 7.32 7.32 7.46 7.20 7.50 7.51 7.67 7.53 7.86 7.62 7.35 7.60 7.34 7.34 7.28 7.23 7.40 6.95 6.76 7.23 7.19 7.47 7.26 7.39 6.93 7.08 7.16  K2O 0.51 0.63 0.57 0.55 0.55 0.52 0.61 0.60 0.59 0.53 0.55 0.56 0.63 0.56 0.50 0.50 0.54 0.51 0.49 1.09 0.46 0.47 0.52 0.47 0.49 0.49 0.41 0.50  MgO 0.00 0.00 0.00 0.02 0.03 0.00 0.00 0.03 0.01 0.00 0.02 0.00 0.00 0.02 0.01 0.00 0.00 0.03 0.01 0.02 0.01 0.00 0.03 0.00 0.02 0.01 0.02 0.00  MnO 0.00 0.00 0.00 0.03 0.00 0.01 0.00 0.00 0.04 0.02 0.00 0.00 0.03 0.00 0.02 0.00 0.00 0.00 0.04 0.04 0.00 0.00 0.00 0.00 0.03 0.03 0.01 0.04  FeO 0.19 0.40 0.22 0.24 0.17 0.27 0.34 0.28 0.23 0.36 0.22 0.11 0.23 0.30 0.20 0.28 0.32 0.32 0.34 0.23 0.18 0.17 0.26 0.33 0.28 0.08 0.37 0.28  Total 99.59 100.85 100.16 100.28 98.43 100.87 100.71 102.43 100.48 102.22 102.16 101.13 100.89 100.20 100.85 101.71 101.43 99.86 100.47 101.62 100.91 101.05 100.38 101.47 101.10 100.82 100.37 100.41  mol frac An 0.309 0.307 0.309 0.307 0.303 0.297 0.292 0.298 0.286 0.278 0.295 0.302 0.294 0.306 0.315 0.325 0.321 0.313 0.349 0.295 0.324 0.325 0.310 0.340 0.336 0.342 0.343 0.329  mol frac Ab 0.660 0.656 0.657 0.661 0.664 0.672 0.673 0.668 0.679 0.691 0.673 0.665 0.670 0.661 0.655 0.646 0.647 0.657 0.622 0.637 0.649 0.647 0.660 0.634 0.636 0.629 0.633 0.642  mol frac Or 0.031 0.037 0.034 0.032 0.033 0.031 0.036 0.034 0.035 0.031 0.032 0.033 0.037 0.033 0.029 0.029 0.032 0.030 0.029 0.068 0.027 0.028 0.030 0.027 0.028 0.029 0.024 0.030  7-1-5904-1_1 7-1-5904-1_2 7-1-5904-1_3 7-1-5904-1_4  62.29 61.91 61.73 62.46  24.41 24.55 24.23 24.59  5.87 5.77 5.71 5.66  7.69 7.73 7.90 7.53  0.53 0.55 0.51 0.44  0.00 0.02 0.04 0.01  0.01 0.03 0.08 0.00  0.14 0.19 0.29 0.15  100.95 100.77 100.50 100.84  0.288 0.283 0.277 0.286  0.682 0.685 0.694 0.688  0.031 0.032 0.030 0.026  128  Table A3 continued. Electron microprobe analysis data Label 7-1-5904-1_5 7-1-5904-1_6 7-1-5904-1_7 7-1-5904-1_8 7-1-5904-1_9 7-1-5904-1_10 7-1-5904-1_11 7-1-5904-1_12 7-1-5904-1_13 7-1-5904-1_14 7-1-5904-1_15 7-1-5904-1_16 7-1-5904-1_17 7-1-5904-1_18 7-1-5904-1_19 7-1-5904-1_20 7-1-5904-1_21 7-1-5904-1_22 7-1-5904-1_23 7-1-5904-1_24 7-1-5904-1_25 7-1-5904-1_26 7-1-5904-1_27 7-1-5904-1_28 7-1-5904-1_29 7-1-5904-1_30 7-1-5904-1_31 7-1-5904-1_32 7-1-5904-1_33 7-1-5904-1_34 7-1-5904-1_35 7-1-5904-1_36 7-1-5904-1_37  SiO2 61.94 61.71 61.69 62.62 62.77 61.77 62.06 61.61 61.98 61.43 61.57 61.05 61.45 61.16 61.94 62.18 62.42 62.45 62.11 62.41 62.81 62.81 62.96 62.72 62.81 63.46 64.03 63.17 64.33 63.06 64.65  Al2O3 24.59 24.29 24.20 24.44 24.29 24.04 24.37 24.17 23.78 23.83 24.24 24.25 24.16 24.12 24.24 24.21 23.82 23.91 24.03 23.98 23.41 23.37 23.13 23.26 23.22 23.39 23.39 23.36 23.18 23.33 22.91  CaO 5.91 5.73 5.65 5.63 5.67 5.61 5.45 5.49 5.39 5.22 5.52 5.74 6.04 5.74 5.94 5.80 5.36 5.33 5.47 5.10 4.89 4.92 4.58 4.63 4.54 4.55 4.76 4.57 4.74 4.58 4.50  Na2O 7.75 7.62 7.47 7.91 7.98 7.69 7.93 7.85 7.57 7.94 7.86 7.61 7.88 7.86 7.56 7.82 7.74 7.87 7.89 8.10 8.30 8.14 8.27 8.35 8.29 8.26 8.37 8.59 8.14 8.16 8.33  K2O 0.55 0.56 0.57 0.60 0.52 0.49 0.48 0.56 0.63 0.62 0.58 0.51 0.50 0.49 0.46 0.52 0.55 0.62 0.52 0.58 0.62 0.61 0.60 0.67 0.68 0.59 0.56 0.62 0.59 0.69 0.62  MgO 0.00 0.03 0.00 0.00 0.00 0.01 0.02 0.00 0.01 0.02 0.02 0.01 0.00 0.02 0.00 0.00 0.00 0.01 0.03 0.02 0.00 0.00 0.01 0.00 0.01 0.00 0.00 0.01 0.01 0.01 0.00  MnO 0.00 0.07 0.06 0.04 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.05 0.00 0.00 0.00 0.00 0.00 0.06 0.04 0.01 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.03  FeO 0.20 0.21 0.16 0.17 0.16 0.19 0.29 0.22 0.11 0.09 0.14 0.15 0.22 0.25 0.32 0.23 0.23 0.28 0.20 0.16 0.12 0.21 0.22 0.25 0.14 0.23 0.18 0.19 0.18 0.12 0.22  129  Total 100.94 100.23 99.81 101.40 101.39 99.81 100.60 99.91 99.48 99.16 99.96 99.32 100.25 99.68 100.46 100.76 100.13 100.48 100.24 100.41 100.19 100.06 99.76 99.88 99.70 100.48 101.30 100.52 101.18 99.96 101.25  mol frac An 0.287 0.284 0.285 0.273 0.274 0.279 0.268 0.270 0.272 0.257 0.270 0.285 0.289 0.279 0.295 0.282 0.268 0.262 0.269 0.249 0.237 0.242 0.226 0.225 0.223 0.225 0.231 0.219 0.235 0.227 0.222  mol frac Ab 0.681 0.683 0.681 0.693 0.697 0.692 0.704 0.698 0.691 0.707 0.696 0.685 0.682 0.692 0.678 0.688 0.700 0.701 0.701 0.717 0.727 0.723 0.739 0.736 0.737 0.740 0.736 0.745 0.730 0.732 0.742  mol frac Or 0.032 0.033 0.034 0.035 0.030 0.029 0.028 0.033 0.038 0.036 0.034 0.030 0.029 0.028 0.027 0.030 0.033 0.036 0.030 0.034 0.036 0.036 0.035 0.039 0.040 0.035 0.032 0.035 0.035 0.041 0.036  Table A3 continued. Electron microprobe analysis data Label 7-1-5904-1_38 7-1-5904-1_39 7-1-5904-1_40 7-1-5904-1_41 7-1-5904-1_42 7-1-5904-1_43 7-1-5904-1_44 7-1-5904-1_45 7-1-5904-1_46 7-1-5904-1_47 7-1-5904-1_48 7-1-5904-1_49 7-1-5904-1_50 7-1-5904-1_51 7-1-5904-1_52 7-1-5904-1_53 7-1-5904-1_54 7-1-5904-1_55 7-1-5904-1_56 7-1-5904-1_57 7-1-5904-1_58 7-1-5904-1_59 7-1-5904-1_60 7-1-5904-1_61 7-1-5904-1_62 7-1-5904-1_63 7-1-5904-1_64 7-1-5904-1_65 7-1-5904-1_66 7-1-5904-1_67 7-1-5904-1_68 7-1-5904-1_69 7-1-5904-1_70  SiO2 63.33 64.34 63.92 63.73 63.83 62.96 64.50 63.63 63.66 63.75 63.40 63.23 63.27 63.41 63.22 63.00 63.06 62.55 62.95 62.98 62.85 63.58 63.51 63.26 63.79 63.20 63.42 63.46 64.23 63.12 63.57 64.08  Al2O3 23.07 22.95 23.39 23.50 23.38 23.67 23.05 23.34 23.35 23.14 23.53 23.32 23.34 23.40 23.29 23.32 23.36 23.40 23.05 22.84 23.06 23.54 23.42 23.31 23.30 22.90 23.26 23.19 23.15 23.11 23.50 22.98  CaO 4.53 4.52 4.71 4.83 4.53 4.78 4.85 4.65 4.50 4.79 4.65 4.81 4.63 4.57 4.68 4.55 4.65 4.76 4.56 4.45 4.64 4.50 4.43 4.57 4.55 4.62 4.30 4.59 4.53 4.30 4.33 4.72  Na2O 8.46 8.42 7.99 8.07 8.42 8.05 8.14 8.28 8.57 8.34 8.21 8.07 8.32 8.68 8.23 7.96 8.23 8.34 8.27 8.36 8.47 8.26 8.54 8.50 8.42 8.50 8.41 8.34 8.06 8.02 8.20 8.16  K2O 0.61 0.62 0.66 0.53 0.70 0.63 0.65 0.74 0.62 0.67 0.76 0.56 0.66 0.63 0.66 0.59 0.62 0.66 0.69 0.70 0.63 0.72 0.70 0.71 0.66 0.63 0.67 0.66 0.75 0.62 0.65 0.62  MgO 0.02 0.02 0.01 0.02 0.00 0.00 0.01 0.00 0.00 0.02 0.00 0.01 0.00 0.00 0.05 0.00 0.02 0.00 0.02 0.01 0.04 0.02 0.01 0.04 0.02 0.00 0.00 0.00 0.01 0.00 0.00 0.00  MnO 0.00 0.01 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.03 0.06 0.00 0.00 0.03 0.00 0.03 0.03 0.00 0.02 0.06 0.00 0.03 0.00 0.00 0.03 0.04 0.00 0.00 0.00  FeO 0.23 0.22 0.22 0.16 0.18 0.14 0.19 0.10 0.14 0.22 0.15 0.17 0.09 0.12 0.10 0.12 0.12 0.11 0.04 0.16 0.09 0.04 0.25 0.15 0.14 0.18 0.06 0.17 0.07 0.10 0.16 0.19  130  Total 100.25 101.08 100.90 100.84 101.05 100.22 101.38 100.75 100.85 100.92 100.69 100.17 100.33 100.88 100.23 99.54 100.08 99.81 99.62 99.54 99.78 100.69 100.92 100.53 100.90 100.03 100.13 100.43 100.84 99.27 100.41 100.74  mol frac An 0.220 0.221 0.236 0.241 0.220 0.238 0.238 0.227 0.217 0.232 0.228 0.240 0.226 0.217 0.230 0.232 0.229 0.231 0.224 0.218 0.224 0.222 0.214 0.220 0.221 0.223 0.212 0.224 0.226 0.220 0.217 0.233  mol frac Ab 0.744 0.743 0.725 0.728 0.740 0.725 0.724 0.730 0.748 0.730 0.728 0.727 0.735 0.747 0.732 0.733 0.734 0.731 0.736 0.741 0.740 0.736 0.746 0.740 0.741 0.741 0.749 0.737 0.729 0.742 0.744 0.730  mol frac Or 0.035 0.036 0.039 0.032 0.041 0.037 0.038 0.043 0.036 0.039 0.044 0.033 0.038 0.036 0.039 0.036 0.036 0.038 0.040 0.041 0.036 0.042 0.040 0.041 0.038 0.036 0.039 0.038 0.045 0.038 0.039 0.037  Table A3 continued. Electron microprobe analysis data Label 7-1-5904-1_71 7-1-5904-1_72 7-1-5904-1_73 7-1-5904-1_74 7-1-5904-1_75 7-1-5904-1_76 7-1-5904-1_77 7-1-5904-1_78 7-1-5904-1_79 7-1-5904-1_80 7-1-5904-1_81 7-1-5904-1_82 7-1-5904-1_83 7-1-5904-1_84 7-1-5904-1_85 7-1-5904-1_86 7-1-5904-1_87 7-1-5904-1_88 7-1-5904-1_89 7-1-5904-1_90 7-1-5904-1_91 7-1-5904-1_92 7-1-5904-1_93 7-1-5904-1_94 7-1-5904-1_95 7-1-5904-1_96 7-1-5904-1_97 7-1-5904-1_98 7-1-5904-1_99 7-1-5904-1_100  SiO2 63.20 63.57 63.26 62.99 64.24 63.38 62.91 62.80 62.82 64.17 63.39 63.82 64.32 63.14 63.26 63.01 63.27 65.11 63.60 64.70 64.82 63.17 65.06 64.02 63.57 63.51 65.02 65.40 63.66 64.53  Al2O3 22.97 22.73 23.23 23.05 23.03 23.53 23.45 23.05 23.20 23.24 23.22 23.44 22.98 23.03 22.75 23.15 23.20 22.81 22.99 23.04 23.08 22.84 22.77 22.90 22.93 22.66 22.67 22.74 22.61 22.54  CaO 4.46 4.32 4.45 4.55 4.40 4.65 4.51 4.55 4.57 4.48 4.62 4.53 4.55 4.72 4.32 4.57 4.53 4.35 4.40 4.00 4.29 4.14 3.97 4.12 4.26 4.08 4.08 4.24 4.02 4.08  Na2O 8.17 8.37 8.35 7.98 8.37 8.24 8.24 8.14 8.48 8.17 8.36 8.28 8.34 8.32 8.17 8.09 8.25 8.57 8.42 8.43 8.69 8.36 8.81 8.42 8.16 8.20 8.16 8.66 8.25 8.45  K2O 0.79 0.71 0.72 0.64 0.64 0.63 0.66 0.60 0.61 0.73 0.69 0.63 0.70 0.69 0.84 0.68 0.73 0.79 0.67 0.85 0.71 0.83 0.81 0.83 0.75 0.68 0.79 0.74 0.79 0.74  MgO 0.01 0.03 0.01 0.00 0.01 0.03 0.00 0.00 0.01 0.01 0.02 0.01 0.02 0.01 0.01 0.01 0.02 0.01 0.00 0.02 0.00 0.00 0.00 0.00 0.03 0.01 0.00 0.00 0.00 0.01  MnO 0.02 0.00 0.00 0.09 0.00 0.05 0.07 0.02 0.07 0.02 0.02 0.01 0.03 0.05 0.00 0.00 0.04 0.00 0.04 0.00 0.00 0.03 0.00 0.00 0.05 0.02 0.00 0.00 0.00 0.00  FeO 0.04 0.02 0.14 0.12 0.11 0.17 0.10 0.19 0.08 0.03 0.11 0.11 0.15 0.04 0.11 0.13 0.14 0.05 0.18 0.05 0.16 0.16 0.11 0.15 0.11 0.12 0.11 0.16 0.04 0.11  131  Total 99.67 99.76 100.15 99.42 100.80 100.68 99.94 99.35 99.84 100.85 100.43 100.83 101.10 99.99 99.46 99.65 100.19 101.67 100.31 101.11 101.76 99.54 101.53 100.44 99.85 99.27 100.83 101.94 99.37 100.45  mol frac An 0.221 0.213 0.218 0.230 0.217 0.229 0.223 0.228 0.221 0.223 0.225 0.224 0.222 0.229 0.215 0.228 0.223 0.209 0.215 0.197 0.206 0.204 0.190 0.203 0.214 0.207 0.206 0.204 0.202 0.202  mol frac Ab 0.732 0.746 0.740 0.731 0.746 0.734 0.738 0.737 0.743 0.734 0.736 0.739 0.737 0.731 0.735 0.731 0.734 0.746 0.746 0.753 0.754 0.747 0.764 0.749 0.741 0.752 0.746 0.754 0.751 0.755  mol frac Or 0.047 0.042 0.042 0.039 0.038 0.037 0.039 0.036 0.035 0.043 0.040 0.037 0.041 0.040 0.050 0.040 0.043 0.045 0.039 0.050 0.041 0.049 0.046 0.049 0.045 0.041 0.048 0.042 0.047 0.044  APPENDIX G: Backscattered electron images Backscattered electron images were collected with a Philips XL-30 scanning electron microscope with a Bruker Quantax 200 Microanalysis System and an XFLASH 4010 detector. These images can be digitally enhanced in Adobe Photoshop™ by shortening the limits of the image histogram (frequency of pixels at each greyscale value), to increase the bandwidth over which information within the image is displayed. Here I display only the original BSE images in figures A2 and A3, but I have included digitally enhanced BSE images in the digital appendices.  132  Figure 20. Backscattered electron images of crystals from HW0604.  133  134  135  136  137  138  139  140  141  Figure 21. Backscattered electron images of crystals from HW0607.  142  143  144  145  146  147  148  149  APPENDIX H: Nomarski differential interference contrast images Etched and carbon coated crystals were viewed using NDIC lenses on a Nikon Optiphot polarizing microscope with reflected light and imaged using a QIMAGING RETIGA EXi digital video camera. Figures A4 and A5 below show original NDIC Images from HW0604 and HW0607, respectively.  150  Figure 22. Nomarski differential interference contrast images from HW0604.  151  152  153  154  155  156  157  158  Figure 23. Nomarski differential interference contrast images from HW0607.  159  160  161  162  163  164  APPENDIX I: Preparation of images for image analysis The BSE and Nomarski DIC images were prepared for spectral analyses in Adobe Photoshop™ by placing white dots on the images. These dots correspond to the beginning and ending points of greyscale profiles to be taken, and they were placed such that several greyscale profiles could be measured on the image parallel to cleavage, or twinning direction (starting and ending on the same zone). Next, ImageJ™ software was used to measure greyscale profiles across the crystal as marked, recording the greyscale intensities. The profiles were collected and saved as .txt files, and aligned using MatLab™ (Appendix K) so that all profiles start at the same relative position to a particular zone. The aligned profiles were then averaged to maximize the signal to noise ratio.  165  APPENDIX J: Greyscale traverses of NDIC images  Figure 24. Graphs of greyscale traverses across NDIC images.  166  167  168  APPENDIX K: MatLab codes Nomarski image analysis clear all close all %% LOAD IN DATA load short743512.txt y1 = short743512; %greyscale values measured parallel to cleavage or twinning %% PREPARE DATA FOR ANALYSES for i=1:5  ;  nonNaN = y1(y1(:,i)==y1(:,i),i); %Finds all values for a column that are not NaN's in column i x = [1:length(nonNaN)]'*5.914e-7; %Measurement spacing of pixels %5.914e-7 for 10x mag %approx 1.46e-7 for 40x mag %CHANGE BELOW AS WELL!!! yy = nonNaN;  %All the number values for column i  %% REMOVING PEAKS CAUSED BY START/END DOTS ON IMAGES %MY METHOD: %Find front peak poly= polyfit(x,yy,1); fitp=polyval(poly,x); peak = find (yy(1:10,1) > (fitp(1:10,1) + 1000)); %Remove front peak p=(length(peak)) + 1; for m = p:length(yy)  169  y4(m-length(peak),1)=yy(m,1); end %Make new yy & x yy = y4; clear y4; x = [1:length(yy)]'*5.914e-7; %Find last peak poly= polyfit(x,yy,1); fitp=polyval(poly,x); peak = find (yy((length(yy)-10):length(yy),1) > (fitp((length(yy)-10):length(yy),1) + 1000)); %Remove last peak q=length(peak); for m = 1:(length(yy)-q) y5(m,1)=yy(m,1); end %Make new yy yy = y5; clear y5; %% AVERAGING THE PROFILES INTO ONE prepped(1:length(yy),i) = yy; for v=1:size(prepped,2) for t=1:length(prepped) if prepped(t,v)==0 prepped(t,v) = NaN; else prepped(t,v) = prepped(t,v); end end end nearlyready = mean(prepped,2); yy = nearlyready(nearlyready(:,1)==nearlyready(:,1),1);  170  end %% LENGTH OF THE SERIES AND DATA SPACING x = [1:length(yy)]'*5.914e-7; %This depends on the number of pixels per metre (SAME AS ABOVE) nx=length(yy); %Number of points in the dataset L = x(length(x))-x(1); %Input this or use length() command dx=L/(nx-1); %Spacing Nyquist = 0.5*(1/dx); %Half of the sample spacing frequency %% DETRENDING %Remove any secular trends from the data (because otherwise %they will appear as very long wavelengths in the spectra). %Difference the data or fit & subtract a polynomial. % DIFF Difference and approximate derivative. % DIFF(X), for a vector X, is [X(2)-X(1) X(3)-X(2) ... %X(n)-X(n-1)]. diffyy = diff(yy); %Differenced data (dataset is one data pt shorter) figure(90) plot(x(1:(nx-1)),diffyy,'g') hold on plot(x,yy) title('differencing') xlabel('distance') ylabel('greyscale intensity') % POLYFIT Fit polynomial to data. % P = POLYFIT(X,Y,N) finds the coefficients of a %polynomial P(X) of degree N that fits the data Y best in a %least-squares sense. P is a row vector of length N+1 %containing the polynomial coefficients in descending %powers, P(1)*X^N + P(2)*X^(N-1) +...+ P(N)*X + P(N+1). order = ceil(0.10*length(x)); fitCoeff = polyfit(x,yy,order);  171  fity=polyval(fitCoeff, x); figure(91) subplot(3,1,1) plot(x,fity,'r') hold on plot(x,yy) premove= yy - fity;  %Data with polynnomial removed  plot(x,premove,'g') title('polynomial fitting') %%%%%%%%%%%%%%%%%%%%%%%%%% %Moving polynomial fit order = ceil(0.05*length(x)); %order = 10; width = ceil(0.1*length(x)); step = 0.1*width; [fity2, xx, order] = polyfitp(x,yy,order,width,step); fity2 = fity2'; premove2 = yy-fity2; figure(91) subplot(3,1,2) plot(x,fity2,'r',x,premove2,'b') hold on plot(x,yy) %%%%%%%%%%%%%%% %Moving Gaussian smooth: %JUST TO SHOW IMPLEMENTATION; TRY VARYING #POINTS IN THE MOVING WINDOW AND ALSO WIDTH OF THE CURVE points = ceil(0.01*length(x)); width = 2; premovegauss = FilterGauss(premove2,points,width); figure(91) subplot(3,1,3),plot(x,premovegauss,'r',x,premove2,'b') hold on xlabel('distance')  172  %% ZERO PADDING (can see what is happening near the %ends...a useful tool, but not required) % % % make actual data start at xx(addon+1) and end at %xx(end-addon-1): % addon = ceil(0.5*length(yy)); % %x = [zeros(addon,1); x ;zeros(addon,1)]; % % diffyy =[zeros(addon,1); diffyy ;zeros(addon,1)]; % x = [1:length(diffyy)]'*5.914e-7; % % %% Length of the series and data spacing (add in again if %zero padding) % % nx=length(diffyy); %Number of points in the dataset % L = x(length(x))-x(1); %Input this or use length() command % dx=L/(nx-1); %Spacing % Nyquist = 0.5*(1/dx); %Half of the sample spacing frequency %% WINDOWING AND DE-MEANING % Remove the mean and window the profile to minimize edge %effects. %Windowing the data: % HANNING Hanning window. % HANNING(N) returns the N-point symmetric Hanning %window in a column vector. Note that the first and last %zero-weighted window samples are not included. % w(n)=0.5*(1-cos((2*pi*n)/(N-1))) % %Window the mean removed data % window2=hanning(nx); % y=(yy-mean(yy)).*window2; % % figure(92) % plot(x,y) % xlabel('x') % ylabel('windowed & mean removed y(x)') %Window the differenced data diffnx=length(diffyy); %Number of points in the dataset window=hanning(diffnx);  173  diffy=(diffyy-mean(diffyy)).*window; %differenced, mean removed, and windowed diffw=(diffyy-mean(diffyy)); %differenced and mean removed only figure(93) plot(x(1:(nx-1)),diffy) % plot(x(1:(nx)),diffy) %use this line when zero padding xlabel('x') ylabel('windowed, differenced & mean removed y(x)')  %Window the polynomial removed data window2=hanning(nx); premy=(premove-mean(premove)).*window2; figure(94) plot(x,premy) hold on title('BLUE=polynomial removed, GREEN=step poly removed, RED=gauss') xlabel('x') ylabel('windowed, polynomial & mean removed y(x)') premy2=(premove2-mean(premove2)).*window2; plot(x,premy2,'g') premgauss=(premovegauss-mean(premovegauss)).*window2; plot(x,premgauss,'r') %% LOW PASS FILTERING (If needed) % % BUTTER Butterworth digital and analog filter design. % % [B,A] = BUTTER(N,Wn) designs an Nth order lowpass %digital Butterworth filter and returns the filter %coefficients in length N+1 vectors B (numerator) and A %(denominator). The coefficients are listed in descending %powers of z. The cutoff frequency Wn must be 0.0 < Wn < %1.0, with 1.0 corresponding to half the sample rate. % % The Butterworth filter rolls off more gradually at the %cutoff frequency than some other common filters (i.e. %Chebyshev, elliptic) and doesn't have any ripples either  174  %before or after the cutoff frequency. % I can use the Butterworth filter to remove frequencies %above Nyquist to avoid aliasing. % %Multiply by transfer function % %H(iw) = |out| / |in| ; numerator and denominator are %polynomials of order 'order'. Sharpness of cutoff %increases with order at expense of information. Cutoff is %frequency below which signals are permitted. % cutoff = 0.7; %low pass frequency cutoff in fractions of Nyquist; %1=NYQUIST maxfreq = cutoff; order = 10; [out in] = butter( order , maxfreq,'low'); diffy = filtfilt( out , in , diffy); % diffy = filter( out , in , diffy); diffw = filtfilt( out , in , diffw); % diffw = filter( out , in , diffw); %% OTHER FILTERS (TRY) % [out2,in2] = butter(order , maxfreq ,'high'); %a highpass filter with cutoff Wn % diffy = filter( out2 , in2 , diffy); % diffw = filter( out2 , in2 , diffw); % [out3,in3] = butter(order, [0.5 maxfreq] ,'stop'); %an order 2*n bandstop digital filter % diffy = filter( out3 , in3 , diffy); %if Wn is a two-element vector, Wn = [w1 w2]. % diffw = filter( out3 , in3 , diffw); %The stopband is w1 < ? < w2. % figure(30) % plot(x(1:(nx-1)),diffy,x(1:(nx-1)),diffw,'g') % hold on %% WAVENUMBERS % Generate the wavenumber or frequency. if these %wavenumbers are wrong the answer will be wrong and the %imaginary part of the result will be large. k = -nx/2:(nx/2-1); k = k'./L;  175  k2 = -diffnx/2:(diffnx/2-1); k2 = k2'./L; %% FFT % Calculate the FFT windowed and mean removed data % z = real(fftshift(fft(y))); % power = abs(z).^2; % Calculate the FFT with differenced, windowed and mean %removed data diffz = real(fftshift(fft(diffy))); diffpower = abs(diffz).^2; % Calculate the FFT with polynomial removed, windowed and %mean removed data prz = real(fftshift(fft(premy))); prpower = abs(prz).^2;  %polynomial removed  prz2 = real(fftshift(fft(premy2))); %step polynomial removed prpower2 = abs(prz2).^2; prz3 = real(fftshift(fft(premgauss))); prpower3 = abs(prz3).^2;  %gauss  %% WELCH METHOD % %Power spectra via Welch method % %[Pxx,F] = PWELCH(X,WINDOW,NOVERLAP,NFFT,Fs,'onesided' OR %'twosided' if complex) need complex part to get phase from %cross-spectra); No window specified equals 8 overlapping %segments. Note default taper is a Hanning window (cosine) window = round(length(yy)/3); %window = []; noverlap = round(window/2); %noverlap = []; %nfft = length(y); nfft = []; [P1,F1] = pwelch(diffw,window,noverlap,nfft,1/dx,'onesided'); figure(999)  176  semilogx(1./F1,P1./(max(P1)),'g') hold on semilogx(1./k2,diffpower./(max(diffpower))) xlabel('Period') ylabel('Normalized Power') %% MULTI TAPER METHOD [PM, FM] = pmtm(diffw,2,[],1/dx,'adapt','onesided'); semilogx(1./FM,PM./(max(PM)),'r-') %% FIGURES scalepower = 1.0; % %Raw data with zero mean % %x=x./(24*3600); % % figure(100) % hold on % % subplot(3,1,1),plot(x,yy./(max(yy)*scalepower)) % xlabel('x') % ylabel('y(x)') % % subplot(3,1,2), plot(x,y./(max(y))*scalepower) % xlabel('x') % ylabel('windowed y(x)') % % subplot(3,1,3), semilogx(1./k,power./(max(power)*scalepower),'b--') % xlabel('Period') % ylabel('normalized power') % % %Differenced data with zero mean % % i=1:1:(L-1); % xx = x(1:(nx-1)); % % kp=k(i); % % figure(110) % hold on % subplot(3,1,1),plot(xx,(diffyy./(max(diffyy)*scalepower))) %  177  % % % % % % % %  xlabel('x') ylabel('diff y(x)') subplot(3,1,2), plot(xx,(diffy./(max(diffy)*scalepower))) xlabel('x') ylabel('windowed diff y(x)') subplot(3,1,3),  % semilogx(1./k2,diffpower./(max(diffpower)*scalepower)) % xlabel('Period') % ylabel('normalized power')  % hold on % % % semilogx(1./k2,diffpower./max(diffpower),'r--') % %Polynomial removed data with zero mean figure(120) hold on % % % % % % % % %  subplot(3,1,1),plot(x,premove./(max(premove)*scalepower)) xlabel('x') ylabel('y(x)') subplot(3,1,2), plot(x,premy./(max(premy))*scalepower) xlabel('x') ylabel('windowed pr y(x)') subplot(3,1,3),  semilogx(1./k,prpower./(max(prpower)*scalepower)) title('BLUE=polynomial removed, GREEN=step poly removed') xlabel('Period') ylabel('normalized power') % semilogx(1./k,prpower2./(max(prpower2)*scalepower),'g') % % semilogx(1./k,prpower3./(max(prpower3)*scalepower),'r') % subplot(3,1,3),  178  semilogx(1./kp,diffpower./(max(diffpower)*scalepower)) % xlabel('Period') % ylabel('normalized power') % hold on % semilogx(1./F1,P1./max(P1),'m') % drivingsucks(1:length(prz),i) = prz; % ihategovt(1:length(prpower),i) = prpower; %clear noverlap F1 FM P1 PM in out L Nyquist diffnx %diffpower diffy diffyy diffw diffz dx fitCoeff clear fity k k2 m maxfreq nonNaN nx p peak points poly power premove premgauss premove2 premovegauss clear premy premy2 prpower prpower2 prpower3 prz prz2 prz3 q scalepower step test test2 width window clear window2 x y yy z %end  179  BSE image analysis clear all close all %% LOAD IN DATA load bpt754202_nc.txt y1 = bpt754202_nc; %greyscale values measured parallel to cleavage or twinning %% PREPARE DATA FOR ANALYSES for i= 1 : 5  ;  nonNaN = y1(y1(:,i)==y1(:,i),i); %Finds all values for a column that are not NaN's in column %i x = [1:length(nonNaN)]'; yy = nonNaN;  %All the number values for column i  %% REMOVING PEAKS CAUSED BY START/END DOTS ON IMAGES %MY METHOD: %Find front peak poly= polyfit(x,yy,1); fitp=polyval(poly,x); peak = find (yy(1:10,1) > (fitp(1:10,1) + 1000)); %Remove front peak p=(length(peak)) + 1; for m = p:length(yy) y4(m-length(peak),1)=yy(m,1); end %Make new yy & x yy = y4;  180  clear y4; x = [1:length(yy)]'; %Find last peak poly= polyfit(x,yy,1); fitp=polyval(poly,x); peak = find (yy((length(yy)-10):length(yy),1) > (fitp((length(yy)-10):length(yy),1) + 1000)); %Remove last peak q=length(peak); for m = 1:(length(yy)-q) y5(m,1)=yy(m,1); end %Make new yy yy = y5; clear y5; %% AVERAGING THE PROFILES INTO ONE prepped(1:length(yy),i) = yy; for v=1:size(prepped,2) for t=1:length(prepped) if prepped(t,v)==0 prepped(t,v) = NaN; else prepped(t,v) = prepped(t,v); end end end nearlyready = mean(prepped,2); yy = nearlyready(nearlyready(:,1)==nearlyready(:,1),1); end %% LENGTH OF THE SERIES AND DATA SPACING x = [1:length(yy)]'*4.0352E-07;  181  %2.0682E-07(743519)  %4.0352E-07(754202) %3.3365E-07(443504) %This depends on the number of pixels/metre *****changes for each image***** nx=length(yy); %Number of points in the dataset L = x(length(x))-x(1); %Input this or use length() command dx=L/(nx-1); %Spacing Nyquist = 0.5*(1/dx); %Half of the sample spacing frequency %% DETRENDING %Remove any secular trends from the data (because otherwise %they will appear as very long wavelengths in the spectra). %Difference the data or fit & subtract a polynomial. % DIFF Difference and approximate derivative. % DIFF(X), for a vector X, is [X(2)-X(1) X(3)-X(2) ... %X(n)-X(n-1)]. diffyy = diff(yy); %Differenced data (dataset is one data pt shorter) figure(90) plot(x(1:(nx-1)),diffyy,'g') hold on plot(x,yy) title('differencing') xlabel('distance') ylabel('greyscale intensity') % POLYFIT Fit polynomial to data. % P = POLYFIT(X,Y,N) finds the coefficients of a %polynomial P(X) of degree N that fits the data Y best in a %least-squares sense. P is a row vector of length N+1 %containing the polynomial coefficients in descending %powers, P(1)*X^N + P(2)*X^(N-1) +...+ P(N)*X + P(N+1). % order = ceil(0.10*length(x)); fitCoeff = polyfit(x,yy,order); fity=polyval(fitCoeff, x); figure(91)  182  subplot(3,1,1) plot(x,fity,'r') hold on plot(x,yy) premove= yy - fity;  %Data with polynnomial removed  plot(x,premove,'g') title('polynomial fitting') %%%%%%%%%%%%%%%%%%%%%%%%%% %Moving polynomial fit order = ceil(0.05*length(x)); %order = 10; width = ceil(0.1*length(x)); step = 0.1*width; [fity2, xx, order] = polyfitp(x,yy,order,width,step); fity2 = fity2'; premove2 = yy-fity2; figure(91) subplot(3,1,2) plot(x,fity2,'r',x,premove2,'b') hold on plot(x,yy) %%%%%%%%%%%%%%% %Moving Gaussian smooth: %JUST TO SHOW IMPLEMENTATION; TRY VARYING #POINTS IN THE %MOVING WINDOW AND ALSO WIDTH OF THE CURVE points = ceil(0.01*length(x)); width = 2; premovegauss = FilterGauss(premove2,points,width); figure(91) subplot(3,1,3),plot(x,premovegauss,'r',x,premove2,'b') hold on xlabel('distance') %% ZERO PADDING (can see what is happening near the ends... %a useful tool,but not required)  183  % % make actual data start at xx(addon+1) and end at %xx(end-addon-1): % addon = ceil(0.5*length(yy)); % %x = [zeros(addon,1); x ;zeros(addon,1)]; % % diffyy =[zeros(addon,1); diffyy ;zeros(addon,1)]; % x = [1:length(diffyy)]'*5.914e-7; % % %% Length of the series and data spacing (add in again if %zero padding) % % nx=length(diffyy); %Number of points in the dataset % L = x(length(x))-x(1); %Input this or use length() command % dx=L/(nx-1); %Spacing % Nyquist = 0.5*(1/dx); %Half of the sample spacing frequency %% WINDOWING AND DE-MEANING % Remove the mean and window the profile to minimize edge %effects. %Windowing the data: % HANNING Hanning window. % HANNING(N) returns the N-point symmetric Hanning %window in a column vector. Note that the first and last %zero-weighted window samples are not included. % w(n)=0.5*(1-cos((2*pi*n)/(N-1))) % %Window the mean removed data % window2=hanning(nx); % y=(yy-mean(yy)).*window2; % % figure(92) % plot(x,y) % xlabel('x') % ylabel('windowed & mean removed y(x)') %Window the differenced data diffnx=length(diffyy); %Number of points in the dataset window=hanning(diffnx); diffy=(diffyy-mean(diffyy)).*window; %differenced, mean removed, and windowed diffw=(diffyy-mean(diffyy));  184  %differenced and mean removed only figure(93) plot(x(1:(nx-1)),diffy) % plot(x(1:(nx)),diffy) %use this line when zero padding xlabel('x') ylabel('windowed, differenced & mean removed y(x)')  %Window the polynomial removed data window2=hanning(nx); premy=(premove-mean(premove)).*window2; figure(94) plot(x,premy) hold on title('BLUE=polynomial removed, GREEN=step poly removed, RED=gauss') xlabel('x') ylabel('windowed, polynomial & mean removed y(x)') premy2=(premove2-mean(premove2)).*window2; plot(x,premy2,'g') premgauss=(premovegauss-mean(premovegauss)).*window2; plot(x,premgauss,'r') %% LOW PASS FILTERING (If needed) % % BUTTER Butterworth digital and analog filter design. % % [B,A] = BUTTER(N,Wn) designs an Nth order lowpass %digital Butterworth filter and returns the filter %coefficients in length N+1 vectors B (numerator) and A %(denominator). The coefficients are listed in descending %powers of z. The cutoff frequency Wn must be 0.0 < Wn < %1.0, with 1.0 corresponding to half the sample rate. % % The Butterworth filter rolls off more gradually at the %cutoff frequency than some other common filters (i.e. %Chebyshev, elliptic) and doesn't have any ripples either %before or after the cutoff frequency. I can use the %Butterworth filter to remove frequencies above Nyquist to %avoid aliasing.  185  % %Multiply by transfer function % %H(iw) = |out| / |in| ; numerator and denominator are %polynomials of order 'order'. Sharpness of cutoff %increases with order at expense of information. Cutoff is %frequency below which signals are permitted. % cutoff = 0.7; %low pass frequency cutoff in fractions of Nyquist; %1=NYQUIST maxfreq = cutoff; order = 10; [out in] = butter( order , maxfreq,'low'); diffy = filtfilt( out , in , diffy); % diffy = filter( out , in , diffy); diffw = filtfilt( out , in , diffw); % diffw = filter( out , in , diffw); %% OTHER FILTERS (TRY) % [out2,in2] = butter(order , maxfreq ,'high'); %a highpass filter with cutoff Wn % diffy = filter( out2 , in2 , diffy); % diffw = filter( out2 , in2 , diffw); % [out3,in3] = butter(order, [0.5 maxfreq] ,'stop'); %an order 2*n bandstop digital filter % diffy = filter( out3 , in3 , diffy); %if Wn is a two-element vector, Wn = [w1 w2]. % diffw = filter( out3 , in3 , diffw); %The stopband is w1 < ? < w2. % figure(30) % plot(x(1:(nx-1)),diffy,x(1:(nx-1)),diffw,'g') % hold on %% WAVENUMBERS % Generate the wavenumber or frequency. if these %wavenumbers are wrong the answer will be wrong and the %imaginary part of the result will be large. k = -nx/2:(nx/2-1); k = k'./L; k2 = -diffnx/2:(diffnx/2-1); k2 = k2'./L;  186  %% FFT % Calculate the FFT windowed and mean removed data % z = real(fftshift(fft(y))); % power = abs(z).^2; % Calculate the FFT with differenced, windowed and mean %removed data diffz = real(fftshift(fft(diffy))); diffpower = abs(diffz).^2; % Calculate the FFT with polynomial removed, windowed and %mean removed data prz = real(fftshift(fft(premy))); prpower = abs(prz).^2;  %polynomial removed  prz2 = real(fftshift(fft(premy2))); %step polynomial removed prpower2 = abs(prz2).^2; prz3 = real(fftshift(fft(premgauss))); prpower3 = abs(prz3).^2;  %gauss  %% WELCH METHOD % %Power spectra via Welch method % %[Pxx,F] = PWELCH(X,WINDOW,NOVERLAP,NFFT,Fs,'onesided' OR %'twosided' if complex) need complex part to get phase from %cross-spectra); No window specified equals 8 overlapping %segments. Note default taper is a Hanning window (cosine) window = round(length(yy)/3); %window = []; noverlap = round(window/2); %noverlap = []; %nfft = length(y); nfft = []; [P1,F1] = pwelch(diffw,window,noverlap,nfft,1/dx,'onesided'); figure(999) semilogx(1./F1,P1./(max(P1)),'g') hold on semilogx(1./k2,diffpower./(max(diffpower)))  187  xlabel('Period') ylabel('Normalized Power') %% MULTI TAPER METHOD [PM, FM] = pmtm(diffw,2,[],1/dx,'adapt','onesided'); semilogx(1./FM,PM./(max(PM)),'r-') %% FIGURES scalepower = 1.0; % %Raw data with zero mean % %x=x./(24*3600); % % figure(100) % hold on % % subplot(3,1,1),plot(x,yy./(max(yy)*scalepower)) % xlabel('x') % ylabel('y(x)') % % subplot(3,1,2), plot(x,y./(max(y))*scalepower) % xlabel('x') % ylabel('windowed y(x)') % % subplot(3,1,3), %semilogx(1./k,power./(max(power)*scalepower),'b--') % xlabel('Period') % ylabel('normalized power') % % %Differenced data with zero mean % % i=1:1:(L-1); % xx = x(1:(nx-1)); % % kp=k(i); % % figure(110) % hold on % %subplot(3,1,1),plot(xx,(diffyy./(max(diffyy)*scalepower))) % % xlabel('x') % ylabel('diff y(x)') %  188  % % % % %  subplot(3,1,2), plot(xx,(diffy./(max(diffy)*scalepower))) xlabel('x') ylabel('windowed diff y(x)') subplot(3,1,3),  % semilogx(1./k2,diffpower./(max(diffpower)*scalepower)) % xlabel('Period') % ylabel('normalized power')  % hold on % % % semilogx(1./k2,diffpower./max(diffpower),'r--') % %Polynomial removed data with zero mean figure(120) hold on % % % % % % % % %  subplot(3,1,1),plot(x,premove./(max(premove)*scalepower)) xlabel('x') ylabel('y(x)') subplot(3,1,2), plot(x,premy./(max(premy))*scalepower) xlabel('x') ylabel('windowed pr y(x)') subplot(3,1,3),  semilogx(1./k,prpower./(max(prpower)*scalepower)) title('BLUE=polynomial removed, GREEN=step poly removed') xlabel('Period') ylabel('normalized power') % semilogx(1./k,prpower2./(max(prpower2)*scalepower),'g') % % semilogx(1./k,prpower3./(max(prpower3)*scalepower),'r') % subplot(3,1,3), %semilogx(1./kp,diffpower./(max(diffpower)*scalepower)) % xlabel('Period') % ylabel('normalized power')  189  % hold on % semilogx(1./F1,P1./max(P1),'m') % drivingsucks(1:length(prz),i) = prz; % ihategovt(1:length(prpower),i) = prpower; % clear noverlap F1 FM P1 PM in out L Nyquist diffnx %diffpower diffy diffyy diffw diffz dx fitCoeff % clear fity k k2 m maxfreq nonNaN nx p peak points poly %power premove premgauss premove2 premovegauss % clear premy premy2 prpower prpower2 prpower3 prz prz2 %prz3 q scalepower step test test2 width window % clear window2 x y yy z %end  190  EMPA analysis clear all close all %Load in data load h75402w.txt x = h75402w(:,1)*5e-6; %Gives measurement spacing of %probe points (5e-6 because measurements are every 5um) yy = h75402w(:,2);  %The measurements  %Length of the series and data spacing nx=length(yy); %Number of points in the dataset L = x(length(x))-x(1); %Input this or use length() command dx=L/(nx-1); %Spacing Nyquist = 0.5*(1/dx); %Half of the sample spacing frequency %% % %LOW PASS FILTER IF NEEDED %% %Remove any secular trends from the data (because otherwise %they will appear as very long wavelengths in the spectra). %Difference the data or fit & subtract a polynomial. % DIFF Difference and approximate derivative. % DIFF(X), for a vector X, is [X(2)-X(1) X(3)-X(2) ... %X(n)-X(n-1)]. diffyy = diff(yy); %Differenced data (dataset is one data pt shorter) figure(90) plot(x(1:(nx-1)),diffyy,'g') hold on plot(x,yy)  191  % POLYFIT Fit polynomial to data. % P = POLYFIT(X,Y,N) finds the coefficients of a %polynomial P(X) of degree N that fits the data Y best in a %least-squares sense. P is a row vector of length N+1 %containing the polynomial coefficients in descending %powers, P(1)*X^N + P(2)*X^(N-1) +...+ P(N)*X + P(N+1). % fitCoeff = polyfit(x,yy,8); fity=polyval(fitCoeff, x); figure(91) plot(x,fity,'r') hold on plot(x,yy) premove= yy - fity;  %Data with polynnomial removed  plot(x,premove,'g') %% % Remove the mean and window the profile to minimize edge %effects. %Windowing the data: % HANNING Hanning window. % HANNING(N) returns the N-point symmetric Hanning %window in a column vector. Note that the first and last %zero-weighted window samples are not included. % w(n)=0.5*(1-cos((2*pi*n)/(N-1))) %Window the mean removed data window2=hanning(nx); y=(yy-mean(yy)).*window2; %Window the differenced data diffnx=length(diffyy); %Number of points in the dataset window=hanning(diffnx); diffy=(diffyy-mean(diffyy)).*window; %Window the polynomial removed data window2=hanning(nx); premy=(premove-mean(premove)).*window2; %% %  Generate the wavenumber or frequency.  192  If these  %wavenumbers are wrong the answer will be wrong and the %imaginary part of the result will be large. k = -nx/2:(nx/2-1); k = k'./L; k2 = -diffnx/2:(diffnx/2-1); k2 = k2'./L; % % Calculate the FFT windowed and mean removed data z = real(fftshift(fft(y))); power = abs(z).^2; % Calculate the FFT with differenced, windowed and mean %removed data diffz = real(fftshift(fft(diffy))); diffpower = abs(diffz).^2; % Calculate the FFT with polynomial removed, windowed and %mean removed data prz = real(fftshift(fft(premy))); prpower = abs(prz).^2; %%Figures scalepower = 1.0; xx = x(1:(nx-1)); figure(120) hold on semilogx(1./k2,diffpower./(max(diffpower)*scalepower),'g') xlabel('Period') ylabel('normalized power') hold on %Polynomial removed data with zero mean figure(120) semilogx(1./k,prpower./(max(prpower)*scalepower)) xlabel('Period') ylabel('normalized power')  193  Confidence intervals %I run my nomarskim.m file, then use this to make figs with %confidence intervals using alex sanchez's specwelch code [psdf, conf, f]=specwelch(diffw, dx, 'hamming', 8, 50); %diffw is the demeaned and detrended data from nomarskim.m %dx is the data spacing %can choose hamming, hanning or boxcar windows %8 is the number of segments (but can be modified) %50 is the amount of overlap between segments figure(878) semilogx(1./f,psdf./(max(psdf)),'c') hold on semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,1)),'c') semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,2)),'c') clear psdf conf f [psdf, conf, f]=specwelch(diffw, dx, 'hamming', 1, 50); semilogx(1./f,psdf./(max(psdf)),'b') semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,1)),'b') semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,2)),'b') clear psdf conf f [psdf, conf, f]=specwelch(diffw, dx, 'hamming', 2, 50); semilogx(1./f,psdf./(max(psdf)),'r') semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,1)),'r') semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,2)),'r') clear psdf conf f [psdf, conf, f]=specwelch(diffw, dx, 'hamming', 4, 50); semilogx(1./f,psdf./(max(psdf)),'g') semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,1)),'g') semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,2)),'g') clear psdf conf f [psdf, conf, f]=specwelch(diffw, dx, 'hamming', 12, 50); semilogx(1./f,psdf./(max(psdf)),'m') semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,1)),'m')  194  semilogx(1./f,(psdf./(max(psdf))).*(0.95*conf(1,2)),'m')  195  APPENDIX L: Spectra  Figure 25. Graphs of spectra computed from NDIC greyscale profiles.  196  197  198  APPENDIX M: Confidence intervals for the Welch spectral estimation method Shown in Figure A8 are spectra computed using the Welch spectral estimation method showing 95% confidence intervals. These spectra are calculated for crystal 743512 using 1, 2, 4, 8, and 12 segments, respectively, that are each windowed with Hamming windows and have 50% overlap between the windows/segments. Using only one segment/window recovers the spectrum obtained using a simple fast Fourier transform with a Hamming window. In general, the number of peaks in the spectra decreases with an increasing number of segments/windows and the width of the confidence interval becomes narrower with an increasing number of segments/windows used. Spectral estimations in this thesis are computed using the Welch method with eight segments.  199  Figure 26. Plots of confidence intervals using Welch spectral methods.  200  APPENDIX N: Trace element data A suite of trace element data was collected for the crystals in the HW0604 and HW0607 samples using the laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) facility at Rice University, Houston, Texas under the supervision of Dr. Cin-Ty Lee. The locations of analyses (spots and/or traverses) are indicated in Appendix E. These data were not analysed in this thesis, and are thus presented as unprocessed Microsoft Excel™ files in the digital files that accompany this thesis.  201  

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