@prefix vivo: . @prefix edm: . @prefix ns0: . @prefix dcterms: . @prefix skos: . vivo:departmentOrSchool "Science, Faculty of"@en, "Earth, Ocean and Atmospheric Sciences, Department of"@en ; edm:dataProvider "DSpace"@en ; ns0:degreeCampus "UBCV"@en ; dcterms:creator "Cone, Dylan"@en ; dcterms:issued "2020-12-08T21:28:44Z"@en, "2020"@en ; vivo:relatedDegree "Master of Science - MSc"@en ; ns0:degreeGrantor "University of British Columbia"@en ; dcterms:description "Low-Cr and high-Cr clinopyroxene, garnet, olivine, and ilmenite megacrysts from the Muskox kimberlite (Nunavut, Canada) have been analyzed for major and trace elements, as well as Sr, Nd and Pb isotopes in an attempt to constrain the debated origin of the kimberlitic megacryst suite. Samples display compositional overlap with respective phases in websterite, while clinopyroxene Sr-Nd-Pb isotope systematics reveal similarities with both websteritic clinopyroxene and metasomatic clinopyroxene in peridotites from the same kimberlite, in addition to whole-rock isotope data for the Muskox and neighboring Jericho kimberlites. All studied lithologies may represent the products of mixing between EM1 mantle, locally restricted relic Proterozoic enriched mantle and HIMU carbonatitic fluid. Equilibrium melts calculated using clinopyroxene trace element data reaffirm a carbonatitic affinity of the metasomatic agent. Thermodynamic modeling using the Deep Earth Water model shows that megacryst mineral compositions cannot be produced through metasomatism of mantle peridotite by H₂O-rich kimberlitic, asthenospheric or eclogitic fluids. The Sr-Nd-Pb isotope systematics argue against a strictly cognate relationship between Muskox megacrysts and the host kimberlite. Our findings rather suggest megacrysts and websterites represent products formed through regional metasomatism by carbonatitic HIMU fluids that predate kimberlitic magmatism."@en ; edm:aggregatedCHO "https://circle.library.ubc.ca/rest/handle/2429/76700?expand=metadata"@en ; skos:note "CRYSTALLIZATION OF MEGACRYSTS BY CARBONATITIC METASOMATISM: EVIDENCE FROM THE MUSKOX KIMBERITE, NUNAVUT, CANADA by DYLAN CONE B.S., Montclair State University, 2018A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE in THE FACULTY OF GRADUATE AND POSTDOCTORATE STUDIES (Geological Sciences) THE UNIVERSITY OF BRITISH COLUMBIA (Vancouver) December 2020 Ó Dylan Cone, 2020The following individuals certify that they have read, and recommend to the Faculty of Graduate and Postdoctoral Studies for acceptance, the thesis entitled: Crystallization of megacrysts by carbonatitic metasomatism: Evidence from the Muskox kimberlite, Nunavut, Canada submitted by Dylan Cone in partial fulfillment of the requirements for the degree of Master of Science in Geological Sciences Examining Committee: Maya Kopylova, Geological Sciences, UBC Supervisor James Scoates, Geological Sciences, UBC Supervisory Committee Member Matthijs Smit, Geological Sciences, UBC Supervisory Committee Member Dominique Weis, Geological Sciences, UBC Additional Examiner iiAbstract Low-Cr and high-Cr clinopyroxene, garnet, olivine, and ilmenite megacrysts from the Muskox kimberlite (Nunavut, Canada) have been analyzed for major and trace elements, as well as Sr, Nd and Pb isotopes in an attempt to constrain the debated origin of the kimberlitic megacryst suite. Samples display compositional overlap with respective phases in websterite, while clinopyroxene Sr-Nd-Pb isotope systematics reveal similarities with both websteritic clinopyroxene and metasomatic clinopyroxene in peridotites from the same kimberlite, in addition to whole-rock isotope data for the Muskox and neighboring Jericho kimberlites. All studied lithologies may represent the products of mixing between EM1 mantle, locally restricted relic Proterozoic enriched mantle and HIMU carbonatitic fluid. Equilibrium melts calculated using clinopyroxene trace element data reaffirm a carbonatitic affinity of the metasomatic agent. Thermodynamic modeling using the Deep Earth Water model shows that megacryst mineral compositions cannot be produced through metasomatism of mantle peridotite by H2O-rich kimberlitic, asthenospheric or eclogitic fluids. The Sr-Nd-Pb isotope systematics argue against a strictly cognate relationship between Muskox megacrysts and the host kimberlite. Our findings rather suggest megacrysts and websterites represent products formed through regional metasomatism by carbonatitic HIMU fluids that predate kimberlitic magmatism. iiiLay Summary During eruption, kimberlitic magmas carry a variety of foreign material with them on their journey to the surface, including abnormally large crystals (>1 cm) of mantle origin known as “megacrysts.” While first noted for their unusual size, these crystals also have distinct chemical compositions when compared to the same minerals in mantle peridotite. The origin of these crystals is still debated, and two primary models exist on how they form: megacrysts either crystallize from a distinct magma in the mantle, or they crystallize when fluids react with existing mantle rock (metasomatism). In this thesis I studied the isotopic and chemical compositions of megacrysts from a single kimberlite in Nunavut, Canada. With these data, I used computer code to recreate the chemical reactions taking place in the Earth’s upper mantle to determine whether megacrysts can be formed by fluid-rock reactions, as well as constrain the composition of this fluid. ivPreface This thesis was prepared in manuscript format following acceptance for publication in the Journal of the Geological Society, an international, peer-reviewed scientific journal. The manuscript is entitled “Crystallization of megacrysts by carbonatitic metasomatism: evidence from the Muskox kimberlite, Nunavut, Canada” with myself and my supervisor Maya Kopylova as authors. I am the lead author and responsible for data collection, data interpretation, figure design and manuscript preparation while Maya Kopylova provided the samples, project design, guidance and editing assistance. Dr. Dimitri Sverjensky (Johns Hopkins University) provided the asthenospheric and eclogitic fluid files used in Deep Earth Water modeling and graciously agreed to review the manuscript prior to submission. Dr. Margharelay Amini was responsible for setting up the LA-ICP-MS protocol used for both trace element and Pb isotope measurements at the Pacific Center of Isotopic and Geochemical Research (PCIGR) at UBC. Sr-Nd-Pb isotope measurements of clinopyroxenes were also performed by PCIGR at UBC. vTable of contents Abstract ............................................................................................................................. iii Lay Summary ................................................................................................................... iv Preface .................................................................................................................................v Table of Contents ............................................................................................................. vi List of Tables .................................................................................................................. viii List of Figures ................................................................................................................... ix Acknowledgements ......................................................................................................... xii Dedication ....................................................................................................................... xiv Chapter 1: Introduction ....................................................................................................1 1.1 The Kimberlitic Megacryst Suite ..............................................................................1 1.2 Research Rationale ....................................................................................................2 1.3 Magmatic Models of Megacryst Crystallization .......................................................2 1.4 Metasomatic Models of Megacryst Crystallization ................................................12 Chapter 2: Analytical Techniques ..................................................................................20 2.1 Scanning Electron Microscope ...............................................................................20 2.2 Electron Microprobe ...............................................................................................20 2.3 Trace Element LA-ICP-MS ....................................................................................21 2.4 in situ Pb Isotopes ...................................................................................................21 2.5 Sr-Nd-Pb Isotopes ...................................................................................................22 Chapter 3: Samples & Petrography ...............................................................................24 3.1 The Muskox and Jericho Kimberlites .....................................................................24 3.2 Petrography of Clinopyroxene Megacrysts ............................................................24 3.3 Petrography of Garnet Megacrysts .........................................................................27 3.4 Petrography of Olivine Megacrysts ........................................................................27 3.5 Petrography of Ilmenite Megacrysts .......................................................................27 3.6 Petrography of Polymineralic Megacrysts ..............................................................29 3.7 Petrography of Muskox Xenoliths ..........................................................................31 Chapter 4: Results ............................................................................................................34 4.1 Major & Trace Element Compositions of Clinopyroxene ......................................34 4.2 Major Element Compositions of Garnet .................................................................39 4.3 Major Element Compositions of Olivine ................................................................39 4.4 Major Element Compositions of Ilmenite ...............................................................41 4.5 Clinopyroxene Sr-Nd-Pb Isotopes ..........................................................................42 Chapter 5: DEW Modeling of Mantle Metasomatism .................................................49 5.1 Modeling Methodology ..........................................................................................49 5.2 Kimberlitic Fluid Results ........................................................................................52 5.3 Asthenospheric Fluid Results .................................................................................56 5.4 Eclogitic Fluid Results ............................................................................................57 Chapter 6: Discussion ......................................................................................................58 6.1 Equilibrium Melt Modeling ....................................................................................58 6.2 Isotope Systematics .................................................................................................60 6.3 DEW Modeling .......................................................................................................64 Chapter 7: Conclusions ...................................................................................................66 7.1 Concluding Remarks ...............................................................................................66 vi 7.2 Future Work ............................................................................................................69 References .........................................................................................................................71 Appendix A: Photographs of Megacrysts ......................................................................85 Appendix B: Major Element Analyses of Megacrysts .................................................94 Appendix C: Trace Element Analyses of Clinopyroxenes .........................................105 Appendix D: in situ Pb Isotope Analyses of Clinopyroxenes .....................................112 Appendix E: Pb-Pb Isochrons ......................................................................................114 Appendix F: Supplementary Isotopic Mixing Figures ...............................................115 viiList of TablesTable 4.1: Major element compositions of Muskox megacrysts ......................................36 Table 4.2: Trace element compositions of Muskox clinopyroxene megacrysts ...............37 Table 4.3: Trace element compositions of Muskox xenoliths and whole-rock Muskox and Jericho kimberlite ...............................................................................................................38 Table 4.4: Isotope compositions of clinopyroxene megacrysts and kimberlite ................46 Table 5.1: Compositions of fluids used in DEW modeling .............................................51 Table 5.2: Modal abundances of product phases from DEW modeling ...........................54 Table 5.3: Solid solution endmembers of product phases from DEW modeling .............55 Table 6.1: Parameters used in isotopic mixing models .....................................................63 viiiList of Figures Fig. 1.1: Mg# vs. TiO2 (wt.%) of garnet megacrysts and CaO (wt.%) vs. Al2O3 (wt.%) for orthopyroxene megacrysts from the Jagersfontein kimberlite displaying magmatic fractionation trends (modified after Hops et al. 1992) ........................................4 Fig. 1.2: Mg# (Ca# in CPX) of silicates vs. Nb (ppm) in ilmenites of intergrown Ilmenite-silicate megacrysts from the Monastery kimberlite (modified after Moore et al. 1992) ....................................................................................................................................4 Fig. 1.3: MgO vs. Cr2O3 of ilmenite megacrysts and polymict mantle breccia (modified after Giuliani et al. 2013) .....................................................................................................8 Fig. 1.4: eHf-eNd for Cr-poor megacrysts and whole-rock kimberlites from SouthAfrica (modified after Nowell et al. 2004) ..........................................................................9 Fig. 1.5: eSr vs. eNd for Group 1 kimberlites and Cr-poor clinopyroxene megacrystsfrom Jagersfontein and other southern African kimberlites (modified after Hops et al. 1992) ....................................................................................................................................9 Fig. 1.6: Sr-Nd isotope compositions of Namibian kimberlites and clinopyroxene megacrysts (modified after Davies et al. 2001). ................................................................11 Fig. 1.7: 207Pb/204Pb vs. 206Pb/204Pb for Namibian kimberlites and clinopyroxene megacrysts (modified after Davies 2001) ..........................................................................11 Fig. 1.8: Major element compositions of Jericho megacrysts (modified after Kopylova et al. 2009) .........................................................................................................................13 Fig. 1.9: Bivariate plots for megacrysts and clinopyroxenes from clinopyroxene-phlogopite xenoliths from the Grib kimberlite (modified after Kargin et al. 2017) .............................................................................................................................15 ixFig. 1.10: Major and minor element compositions of Lac de Gras clinopyroxene and garnet megacrysts (modified after Bussweiler et al. 2018) ................................................16 Fig. 1.11: Nd-Hf isotopic compositions for Jericho garnet-clinopyroxene intergrowths and whole rock Jericho kimberlite (modified after Kopylova et al. 2009) ........................18 Fig. 1.12: Sr isotope systematics of high-Cr clinopyroxene and garnet megacrysts (modified after Bussweiler et al. 2018) ..............................................................................18 Fig. 3.1: SEM photograph of clinopyroxene reaction rim .................................................25 Fig. 3.2: SEM photograph of phlogopite and carbonate inclusions in “spongy” zone of clinopyroxene ................................................................................................................25 Fig. 3.3: SEM photograph of secondary barite in clinopyroxene ......................................26 Fig. 3.4: SEM photograph of serpentine and Fe-Ti oxides in olivine ...............................26 Fig. 3.5: SEM photograph of ilmenite reaction rim ..........................................................28 Fig. 3.6: SEM photograph of perovskite and leucoxene alteration in ilmenite .................28 Fig. 3.7: SEM photograph of phlogopite and apatite inclusions .......................................30 Fig. 3.8: SEM photograph of serpentinization with chromite and phlogopite ..................30 Fig. 3.9: SEM photograph of carbonate and phlogopite inclusions with Fe-Ti Oxides in area of serpentinization ......................................................................................................32 Fig. 3.10: Photomicrographs of primary clinopyroxene in peridotite (a-b), metasomatic clinopyroxene in peridotite (c-d), and clinopyroxene in websterite (e-f) ..........................33 Fig. 4.1: Major element compositions of clinopyroxene megacrysts ................................35 Fig. 4.2: Chondrite-normalized REE patterns for Muskox clinopyroxene megacrysts, clinopyroxenes from Muskox peridotite and clinopyroxene from Muskox websterite .....35 Fig. 4.3: Major element compositions of garnet megacrysts .............................................40 xFig. 4.4: Major element compositions of olivine megacrysts ...........................................40 Fig. 4.5: Major element compositions of ilmenite megacrysts .........................................41 Fig. 4.6: Joint in situ 208Pb/206Pb vs. 207Pb/206Pb isotope systematics .................................43 Fig. 4.7: High-resolution 206Pb/204Pb vs. 207Pb/204Pb isotopic compositions and mixing models for Muskox samples and Jericho kimberlite. Inset is 206Pb/204Pb vs. 208Pb/204Pb ..43 Fig. 4.8: 206Pb/204Pb vs. 143Nd/144Nd compositions of Muskox and Jericho samples and isotopic mixing lines ..........................................................................................................44 Fig. 4.9: 87Sr/86Sr vs. 143Nd/144Nd compositions of Muskox and Jericho samples with calculated mixing lines. .....................................................................................................45 Fig. 5.1: Molal fraction of diopside in clinopyroxene and pyrope in garnet for product phases calculated with the Deep Earth Water (DEW) model ............................................53 Fig. 6.1: Calculated megacryst equilibrium melt compositions using D values for silico-carbonate carbonate melts compared with megacrysts, Muskox kimberlite and Jericho megacrysts .............................................................................................................59 Fig. 6.2: Calculated megacryst equilibrium melt compositions using D values for carbonatitic melts compared with Muskox kimberlite and global carbonatite data ..........59 Fig. 7.1: Proposed model of Muskox megacryst crystallization wherein slab-derived HIMU fluids progressively metasomatize SCLM. ............................................................67 xiAcknowledgements I’d first like to acknowledge my supervisor, Maya Kopylova, for providing the opportunity to work in the Diamond Exploration Laboratory over the past two years. Without her knowledge, guidance and encouragement, this project would not have been possible. I’d also like to thank both members of my committee, James Scoates and Matthijs Smit, who provided excellent feedback and suggestions throughout the evolution of this project, specifically regarding isotopes. Thermodynamic modeling would not have been possible without the collaboration of Dimitri Sverjensky, who generously offered the opportunity to visit Johns Hopkins University for an in-person introduction into the Deep Earth Water model. I’d also like to acknowledge the support, both financial and professional, provided to me by the Diamond Exploration and Research Training School (DERTS) from May 2019 through May 2020. They afforded me wonderful opportunities during the year of my membership, including a chance to present at GAC-MAC in Quebec, a summer internship with Rio Tinto Exploration Canada in downtown Vancouver, and a visit to the University of Alberta to present my research and tour their laboratory facilities. I’d like to extend a special thank you to everyone working at PCIGR for their continuous hard work, both under normal circumstances and through the craziness of 2020. Special praise goes to Dave Daquioag whose quick turnaround in the processing and analysis of our samples allowed them to be included in our manuscript to the Journal of the Geological Society. Marghaleray Amini is thanked for her assistance in both the analysis and data reduction of trace element and in situ Pb isotope measurements. Dominique Weis was an exceptional resource with regards to everything isotope-related in this project, from the earliest stages of sample preparation to thoughtful discussions regarding the conclusions made using our data. xiiSome of my most cherished memories over the last two years here in Vancouver were made in the company of all the wonderful friends I’ve come to know. Whether it was playing cover tunes with “The Diamond Dogs,” going on (sometimes excessively) long bike rides all over Vancouver, or grabbing drinks after an afternoon of rock climbing, life would have been a lot bleaker without their company. I also need to shout out my office mates Sofya Niyazova, Marina Karaevangelou, Skylar Massey and Nester Korolev for always dragging me away from my desk for much needed coffee runs. Lastly, though it’s impossible to put into words, I want to express my appreciation for the love and support I’ve received from my family over the years. KT, I enjoyed every single one of our weekend adventures and much needed talks about life, and my wallet thanks you for smuggling cheap American beer across the border with you. And of course, to my parents, who have been my biggest supporters throughout all of my personal and academic endeavors. Though they probably never fully understood their child’s fascination with rocks, their love has remained consistent no matter the circumstances. xiiiDedication To my mother and father, who never doubted my abilities, even when I did. xivChapter 1 Introduction 1.1 The Kimberlitic Megacryst Suite Megacrysts are large (1 to >20 cm), chemically distinct mantle minerals frequently observed within kimberlite and various alkaline mafic volcanic occurrences across the world. Despite over forty years of research into megacryst petrogenesis, their origin remains enigmatic and a single formation model has yet to satisfy petrologists within kimberlite community. Early magmatic models of megacryst formation (Doyle et al. 2004; Moore and Belousova 2005; Golubkova et al. 2013) gave way to the more recent ideas that megacrysts are the products of progressive metasomatism of lithospheric wallrock, ascribed to reactions with proto-kimberlitic fluids. In these models the metasomatic agent is interpreted broadly as a deep phase present beyond the supercritical endpoint of the peridotite-H2O system, calculated at 1000 °C and 3.8 GPa (Mibe et al. 2007). This cogenetic model was supported by authors who reported compositional overlap between megacrysts and some mantle lithologies (Kopylova et al. 2009; Kargin et al. 2017; Bussweiler et al. 2018), equilibrium melts that were close in composition to silico-carbonate melts (Kopylova et al. 2009; Kargin et al. 2017) and strong isotopic equilibrium with either the host kimberlite (Kopylova et al. 2009) or phases in xenoliths recovered from the same kimberlite pipe (Bussweiler et al. 2018). Constraints on the composition of the megacryst-forming metasomatic agent are hindered by the complex compositional nature of proto-kimberlitic fluids, which may continually evolve along a spectrum from purely carbonatitic (Russell et al. 2012) to silico-carbonate (Brey et al. 2008; Giuliani et al. 2013), closer in composition to that of primary kimberlite melts (Stamm and Schmidt, 2017). Both melt compositions, Ca-carbonatitic and silicate-carbonate, have been shown experimentally to react with the peridotitic mantle to 1crystallize a mineral assemblage similar to that of the kimberlitic megacryst suite, i.e., olivine, high-Ca pyroxene, garnet and Fe-Ti oxides (Gervasoni et al. 2017). 1.2 Research Rationale This study expands on the most recent research that views kimberlitic megacrysts within the framework of mantle metasomatism. Our study employs traditional and novel approaches to unravel the genetic relationship between megacrysts and their host kimberlite, explore possible mechanisms of metasomatic megacryst genesis and constrain the composition of the metasomatic agent. We employ underutilized Pb isotope systematics for constraints on the relationships between kimberlite, megacrysts and additional mantle lithologies, and as a powerful tool in fingerprinting their mantle source. The addition of Pb analyses supplements studies of traditional isotope systems such as Sr-Nd-Hf in the wider context within the local mantle (e.g. Nowell et al. 2004; Kopylova et al. 2009). Our study couples traditional constraints on melt compositions equilibrated with megacrysts with novel fluid-rock reactive modeling (Sverjensky 2019). Here, we report major element, trace element and Sr-Nd-Pb isotope data for a suite of megacrysts from the Muskox kimberlite (Slave craton, Canada). Using these data, we model melts in equilibrium with megacrysts and conclude that carbonatitic fluids were likely to have been involved in megacryst genesis. 1.3 Magmatic Models of Megacryst Crystallization The earliest studies of kimberlitic megacrysts favored petrogenetic models wherein megacrysts were of magmatic origin. These conclusions were based on observed long trends of increasing TiO2, Ca# and Al2O3 with decreasing Cr2O3, Mg#, i.e. correlations expected for 2incompatible elements in evolving and fractionating mafic melts (e.g. Fig. 1.1; Eggler et al. 1979; Boyd et al. 1984; Hops et al. 1992; Moore et al. 1992; Nowell et al. 2004). In these early models, megacrysts enriched in Cr were thought to crystallize first at high temperatures (1050-1400 °C), enriching the melt in both Ti and Fe while depleting it in Cr (Gurney et al. 1979). As the temperature of this magma fell, the crystallization of low-Cr silicate megacrysts ceased, followed immediately by the crystallization of Mg-ilmenite. This is evidenced by the most Mg-rich ilmenite megacrysts (i.e. highest temperature ilmenites) being intergrown with silicate phases belonging to the low-Cr suite (Gurney et al. 1979). This consistent change in mineralogy, parallel with the calculated temperatures of crystallization were cited as strong evidence for a magmatic origin. Similarly, trace element concentrations in ilmenite megacrysts from the Monastery kimberlite are consistent with simple fractionation from a single batch of magma over a wide range of temperatures at isobaric conditions (Moore et al. 1992). Nb contents of ilmenite megacrysts are directly correlated with the Ca# of intergrown clinopyroxene megacrysts, indicating crystallization on a down-temperature trend (Fig. 1.2). Despite these findings, the localization of this magma remains unclear. Some authors suggest fractional crystallization in a differentiating magma body (Eggler et al. 1979; Gurney et al. 1979; Schulze 1987), while others favor megacryst crystallization in “pegmatitic aureoles” surrounding a kimberlitic melt body, a mechanism simultaneously used to explain the origin of sheared peridotite (Moore & Belousova 2005). While many early studies agree megacrysts represent the products of a differentiating magma, diverging opinions exist in both the composition and nomenclature of the melt. Several authors use the term megacryst magma to distinguish a melt that is distinct from the host kimberlite yet offer little additional chemical characteristics (Harte 1983; Schulze, 1985; Doyle et al. 2004; Moore & Belousova, 2005). This term is favored in studies that report significant disequilibrium 3 Fig. 1.1 (a) Mg# vs. TiO2 (wt.%) for Jagersfontein Cr-poor garnet megacrysts and (b) CaO (wt.%) vs Al2O3 (wt.%) for Jagersfontein orthopyroxene megacrysts displaying trends typical for a fractionating magma (Modified after Hops et al. 1992). Fig. 1.2 Mg/Mg+Fe of silicate minerals (Ca/Ca+Mg for CPX, arrow indicating Ca# as a function of decreasing temperature) plotted against Nb contents (ppm) for ilmenite from intergrown ilmenite-silicate megacrysts from the Monastery kimberlite, suggesting a simple fractionation history (Modified after Moore et al. 1992). 4between megacrysts and their host kimberlite, either on the basis of experimental studies, trace element equilibrium modeling, or isotopic systematics and argue the parental melt was not kimberlitic in composition at the time of megacryst crystallization (e.g. Hops et al. 1992). The presence of a distinct megacryst magma simultaneously provides an origin for high-temperature (sheared) peridotites: xenoliths defined by deformed textures and significantly higher crystallization temperatures (1200 °C) than typical cratonic peridotite. Early workers observed thermometric and compositional similarities between megacrysts and sheared peridotites, as well as textural characteristics that would require both suites to crystallize immediately prior to kimberlite entrainment (Harte & Hawkesworth 1989). The wide range in Cr2O3 and TiO2 contents of sheared peridotites were suggested to be metasomatic in origin (Boyd 1975; Ehrenberg 1979, 1982), leading several authors to conclude that sheared peridotites represent cratonic lithosphere thermally and chemically modified by the metasomatism of megacryst magmas (Ehrenberg 1979; Gurney and Hart 1980; Harte 1983). Other authors instead use the term proto-kimberlitic melt, derived from the above term (Mitchell 1986) to describe melts that are initially alkaline, carbonate or silico-carbonate in composition and later evolved to more kimberlitic compositions following megacryst crystallization. This is exemplified in studies that favor garnet megacryst crystallization from melts calculated to be picritic in composition by modeling garnet fractionation trends from kimberlitic, basaltic and picritic melts (Shchukina et al. 2017). In this instance, the calculated parent melt for garnet megacrysts are compositionally similar to the mica-poor alkaline picrites observed in the Arkhangelsk diamondiferous province, previously determined to be in equilibrium with additional megacryst phases (Jones 1987; Nowell and Pearson 1998). Others propose a picritic parental melt that later evolved to a more kimberlitic affinity following megacryst 5crystallization, as it is argued that both kimberlitic and carbonatitic melts would be too Al-poor to crystallize significant quantities of garnet (Agashev et al. 2019). Studies that attempt to calculate equilibrium melts using trace element concentrations of megacrysts frequently report compositions that closely resemble those of alkali basalts (Jones, 1987; Nowell & Pearson 1998). However, it has since been suggested that these experimental D values are inappropriate for this application, as they fail to account for the presence of carbonate in proto-kimberlitic melts (Moore & Belousova 2005). Additionally, alkali basalts have never been observed either as melt inclusions in megacrysts, xenoliths in kimberlite or as igneous bodies spatially related to kimberlites in South Africa, garnering further criticism as a possible parental melt (Moore & Belousova 2005). Many attempt to simplify the megacryst formation model by suggesting megacrysts crystallize directly out of a kimberlitic melt (Eggler et al. 1979; Harte and Gurney 1981; Moore and Belousova 2005; Golubkova et al. 2013). The crystallization of picroilmenite, an abundant megacryst phase, requires a Mg- and Cr-rich melt, argued to be consistent with a kimberlitic parent (Moore and Belousova 2005). Additionally, the unique “chemical fingerprints” of ilmenites from a single kimberlite pipe, commonly used in an exploration context to distinguish discrete kimberlite pipes within a cluster, cannot be reconciled unless they crystallize from their respective host kimberlite (Moore and Belousova 2005). Further evidence for a kimberlitic parent melt includes polymineralic inclusions within megacrysts, calculated to have bulk compositions that are broadly similar to their host kimberlites (Schulze 1985; van Achterbergh et al. 2004; Pivin et al. 2009; Bussweiler et al 2016; Kargin et al. 2017). Often these inclusions include both carbonate and hydrous minerals, such as phlogopite, requiring crystallization in the presence of significant volumes of volatiles (van Achterbergh et al. 62004). It was found that the range of Sr isotopes of polymineralic inclusions in garnet and clinopyroxene megacrysts overlap the host kimberlite, despite not overlapping with the individual megacrysts that contained them (Bussweiler et al. 2017). The general consensus is that these inclusions represent primary kimberlite melt trapped at depth prior to ascent, offering additional evidence that megacrysts are genetically related to their host kimberlite. Studies of quenched glass inclusions in olivine megacrysts reach similar conclusions, attributing variations in glass compositions to differing degrees of evolution of the parent melt: a volatile-rich, carbonated silicate melt similar to a kimberlite (Howarth and Büttner 2019). Individual megacrysts are also reported within polymict mantle breccia, a complex xenolith suite comprised of individual grains of a wide paragenesis cemented together by typical kimberlite groundmass phases. More specifically, the compositional similarity between megacrystic ilmenite (Fig. 1.3), clinopyroxene and garnet with that of equivalent phases from polymict mantle breccias were used to suggest these inclusions represent failed, initially carbonate-rich kimberlitic melts that stalled in the mantle and crystallized megacrysts while progressively metasomatizing the surrounding wallrock (Giuliani et al. 2013, 2014). On the basis of radiogenic isotopes, evidence for a kimberlitic parent melt is supported by reported Nd and Hf isotopic similarities for both megacrysts and their host kimberlite (Fig. 1.4), offering a fractional crystallization model wherein megacrysts and the host kimberlite are genetically related (Nowell et al. 2004). The Sr isotope signature is less radiogenic for megacrysts relative to the host kimberlite, suspected to originate from the incorporation of more radiogenic (crustal) Sr into the host kimberlite during ascent. This degree of isotopic equilibrium had not been observed previously, likely due to earlier studies using isotope systems that are more 7 Fig. 1.3 MgO (wt.%) vs. Cr2O3 (wt. %) plot for different areas of ilmenite grains in polymict mantle breccia xenolith DU-1 (core, rim and interstitial) and ilmenite megacrysts (Mcr) sampled by southern Africa kimberlites (Modified after Giuliani et al. 2013). Ilmenite megacryst compositions from western and southern Africa Group I kimberlites (1) and metasomatic and megacrystal ilmenites (2) are from Haggerty (1991). 8 Fig. 1.4 eHf-eNd for Cr-poor megacrysts from Group I kimberlites and Group II kimberlites, together with fields for respective whole-rock kimberlites. Left-hand side shows the range of eHf for zircon megacrysts from the Orapa, Kaalvallie, Monastery, Gansfontein and Mothae Group I kimberlites (Modified after Nowell et al. 2004). Fig. 1.5 eSr vs. eNd for Group 1 kimberlites and Cr-poor clinopyroxene megacrysts from Jagersfontein and other southern African kimberlites (Modified after Hops et al. 1992). Black lines indicate the mantle array, short dashed lines indicate bulk earth. 9susceptible to contamination (e.g. Sr) or failing to make direct comparisons to the host kimberlite itself. The earlier studies that reported the aforementioned disequilibrium therefore suggested the melt that crystallized megacrysts is neither kimberlitic, nor genetically related to megacrysts (Hops et al. 1992; Davies 2001). Others argue the isotopic systematics of megacrysts are not consistent with fractionation from a single batch of magma, however these studies are unable to rule out a genetic relationship between a megacryst suite and their host kimberlite (Fig. 1.5). Instead, it is suggested that both megacryst and kimberlite magmas were sourced from a single plume-induced melting event, with distinct melt bodies undergoing contrasting evolutionary histories Hops et al. (1992). In this framework, a plume initiates the generation of alkaline magmas that pool and fractionally crystallize megacrysts while simultaneously deforming local peridotite. Melt pockets that interact with peridotite to a larger degree will have a differing isotopic signature and eventually evolve to kimberlite. Alternatively, significant Sr and Pb isotopic disequilibrium between megacrysts and their host kimberlite (Davies et al. 2001; Figs. 1.6 & 1.7) provides two possible scenarios to account for these observations: The first considers megacrysts as the products of plume magmatism sourced from the lower mantle which simultaneously generates kimberlitic magmas. In this model, an impinging plume initiates partial melting of SCLM to generate the melts that crystallize megacrysts, while locally volatile-rich areas of SCLM would instead form kimberlitic melts due to their lower solidus temperatures. The second hypothesis proposed, favored by the author, suggests megacrysts crystallize at the base of the SCLM from magmas generated from plume-sourced fluids interacting with lithospheric mantle. The megacrysts, possessing a depleted Nd and Sr signature, crystallize from melts that had undergone greater degrees of fractionation and interaction with the SCLM and subsequently underwent storage for a significant 10 Fig. 1.6 Initial Sr-Nd isotope compositions of Namibian kimberlites (small dots & triangles in shaded fields) and clinopyroxene megacrysts (symbols in the legend based on locality; after Davies et al. 2001). Fig. 1.7 Present-day (gray triangles & circles) and initial (black field) 206Pb/204Pb vs. 207Pb/204Pb for Namibian kimberlites and clinopyroxene megacrysts (gray squares) compared with flood basalt data in gray fields (Modified after Davies 2001). 11period of time (>10 and <100 Ma) to account for the chemical homogeneity observed. These findings, coupled with trace element data, suggest the megacryst magma to be basaltic in composition. 1.4 Metasomatic Models of Megacryst Crystallization While studies suggesting a magmatic origin laid the early foundation for the elucidation of megacryst petrogenesis, recent publications have favored an origin linked to metasomatism by proto-kimberlitic fluids. This shift was initiated by striking compositional overlap between megacrysts and other unique metasomatic mantle lithologies, as well as calculated equilibrium melts that are closer to kimberlitic in composition (Kopylova et al. 2009; Kargin et al 2017; Bussweiler et al. 2018) and lower degrees of isotopic disequilibrium between kimberlites and megacrysts reported in earlier studies (Kopylova et al. 2009). Numerous authors have based their metasomatic models around compositional overlap between megacrysts and phases within metasomatized mantle rocks. Megacrysts from the Jericho kimberlite (Kopylova et al. 2009), show compositional similarities between high-Cr megacrysts and pyroxenites, as well as low-Cr megacrysts and ilmenite peridotites (Fig. 1.8). These same websterites were concluded by previous workers to be metasomatic in origin, despite possessing magmatic textures (Kopylova et al. 1999), and the same proto-kimberlitic metasomatic reactions could be used to explain the similarities observed between the two suites. Similar mechanisms were used to account for websteritic veins in depleted harzburgites, formed shortly before kimberlite eruption by kimberlitic or precursory carbonatitic fluids, but not the host kimberlite itself (Ionov et al. 2018). A metasomatic origin for websterite is also proposed in a study of xenoliths from the Obnazhennaya kimberlite, wherein websterites were produced by the 12 Fig. 1.8 Major element compositions of Jericho megacrysts (Modified after Kopylova et al. 2009). A, C, E: Cr2O3 vs. Mg/Mg+Fe plot for high-Cr and low-Cr suites of Jericho megacrysts (A-clinopyroxene, C-garnet, E-orthopyroxene) compared with corresponding minerals from Jericho xenoliths, including coarse low-T peridotites (solid outline), sheared high-T peridotites (gray field), ilmenite peridotites and pyroxenites (dashed outline). 13metasomatism of depleted mantle by subduction-related carbonatitic (and TTG) fluids (Taylor et al. 2003). Similar to what is seen at Jericho, high-Cr clinopyroxene megacrysts from the Grib kimberlite (Kargin et al. 2017) are petrographically and compositionally indistinguishable from clinopyroxene in clinopyroxene-phlogopite xenoliths (Fig. 1.9). Trace element analyses of these clinopyroxenes reveal strong negative Nb, Ta, Zr, Hf and Ti anomalies, attributed to metasomatism by kimberlitic or alkaline melts, but may also reflect the signature of subduction processes. These findings led to the conclusion that individual clinopyroxene megacrysts represent disaggregated grains from clinopyroxene-phlogopite xenoliths produced by the metasomatic recrystallization of SCLM peridotite. Similarly, Lac de Gras megacrysts have Cr2O3 and TiO2 contents that overlap compositional fields occupied by clinopyroxene and garnet from peridotite xenoliths from the same kimberlite field (Bussweiler et al. 2018; Fig. 1.10), suggesting megacrysts crystallize from kimberlitic melts that stall in the SCLM and percolate outwards, re-fertilizing depleted harzburgites with garnet and clinopyroxene compositionally indistinguishable to megacrysts. While the specific lithologies in which compositional overlap is seen varies between pipes, the common denominator is that these rocks are inferred to be metasomatic in origin rather than magmatic. This overlap suggests either a common metasomatic agent for both megacrysts and certain mantle lithologies (e.g., websterite, phlogopite-clinopyroxene and refertilized peridotite), or that megacrysts are derived from previous metasomatic lithologies that have been subjected to disaggregation during kimberlite ascent. These findings, coupled with experimental data suggesting megacryst crystallization is not feasible from magmas kimberlitic in composition, offer compounding evidence to suggest that megacrysts represent the products of the progressive metasomatic recrystallization of mantle wallrock. 14 Fig. 1.9 Bivariate plots for megacrysts (stars) and clinopyroxenes from clinopyroxene-phlogopite xenoliths (diamonds) from the Grib kimberlite (Modified after Kargin et al. 2017). Green field represents clinopyroxene from garnet peridotite xenoliths from the same kimberlites. Brown field indicates the range of clinopyroxene from sheared peridotite xenoliths, in equilibrium with Fe-Ti and carbonate bearing magmas from the Grib kimberlite. Purple field is the range of clinopyroxene megacrysts from the Grib kimberlite (Kargin et al. 2004). Dotted orange field shows the range of spongey rims from Cr-rich clinopyroxene megacrysts from Bussweiler et al. (2016). Grey field shows clinopyroxene from phlogopite-ilmenite-garnet peridotite xenoliths from the Grib kimberlite. x-axis in all plots is Mg#. 15 Fig. 1.10 Major and minor element compositions of Lac de Gras clinopyroxene (a & b) and garnet (c) megacrysts (Modified after Bussweiler et al. 2018). Megacrysts have been compared with clinopyroxene and garnet from Lac de Gras peridotite xenoliths (dotted field), as well as global megacryst data (orange, yellow, gray and open circles). 16Despite the strong evidence to suggest a metasomatic origin for kimberlitic megacrysts, there remain diverging opinions on the nature and composition of the metasomatic agent. A number of studies agree the fluid is at least Fe- and Ti-rich (Pivin et al. 2009; Kargin et al. 2017), with others further suggesting enrichments in Al, Si and Ca (Kopylova et al. 2009). Enrichment in Fe and Ti would be necessary to crystallize the low-Cr megacryst suite, consisting of ilmenite (FeTiO3), as well as garnet and clinopyroxene that often display elevated concentrations of these elements relative to peridotitic samples. A metasomatic origin is also favored in studies where megacrysts lack the bi-element correlations between MgO, SiO2, TiO2 and Cr2O3 (e.g., Kopylova et al. 2009; Pivin et al. 2009), trends highlighted in early studies that concluded megacrysts are the products of fractional crystallization. Authors that have modeled equilibrium melts using experimental Kd values have found metasomatic agents to be kimberlitic in composition (Kopylova et al. 2009; Kargin et al. 2017; Bussweiler et al. 2018). Isotopic data from studies that opt for a metasomatic origin have reached contrasting conclusions regarding the genetic relationship between megacrysts and fluids related to the host kimberlite. Isotopic overlap between Jericho megacrysts and their host kimberlite was reached only after correcting for the assimilation of radiogenic crust (Fig. 1.11), which simultaneously yield Rb-Sr, Sm-Nd and Lu-Hf isochron ages that overlap or immediately precede the eruption age of the host kimberlite, suggesting an intimate genetic relationship between megacrysts and their host kimberlite (Kopylova et al. 2009). Other studies report higher degrees of isotopic disequilibrium, instead suggesting megacrysts crystallize from kimberlitic fluids not genetically related to their hosts, such as Sr ratios for clinopyroxene and garnet megacrysts that only extend to the least radiogenic measurements of the host kimberlite (Fig. 1.12), despite possible contamination either by meteoric calcite veins or 17 Fig. 1.11 Calculated Nd-Hf isotopic bulk compositions for Jericho garnet-clinopyroxene intergrowths (solid squares) compared with whole rock host kimberlite (open circles; Modified after Kopylova et al. 2009). All initial ratios for the Jericho megacryst suite have been corrected to the Rb-Sr mica kimberlite emplacement age of 173 ± 1.4 Ma. Filled fields outline compositions for low-Cr megacrysts from South African kimberlites Fig. 1.12 Sr isotope systematics of high-Cr clinopyroxene and garnet megacrysts (Modified after Bussweiler et al. 2018). Samples with an * from van Achterbergh et al. 2002. Lac de Gras megacrysts have been compared with clinopyroxene and garnet megacrysts from the Jericho kimberlite, clinopyroxene from Diavik xenoliths, megacrysts, whole-rock kimberlites from the Lac de Gras province, as well as perovskite from Lac de Gras kimberlites. Lac de Grasmegacrysts18through the assimilation of crustal material (Bussweiler et al. 2018). Comparing this megacryst data to existing Sr isotope data from samples within the Slave craton uncovered isotopic overlap with megacrysts from the Jericho kimberlite, as well as peridotitic clinopyroxenes from the Diavik kimberlite. Despite this disequilibrium, megacryst formation was still attributed to proto-kimberlitic metasomatic processes, however the fluids were unrelated to the host kimberlite. Rather, megacrysts must form from earlier batches of kimberlitic fluids that stall in the mantle, making megacrysts antecrysts in the host kimberlite rather than xenocrysts or cognate material. 19Chapter 2 Analytical Techniques 2.1 Scanning Electron Microscope All megacrysts were first observed on a Philips XL-30 Scanning Electron Microscope (SEM) equipped with both a with a backscattered electron (BSE) unit and Brucker Quantra 200 energy-dispersion X-ray microanalysis system at the Department of Earth and Ocean Sciences at the University of British Columbia (UBC). Operating conditions for energy-dispersive spectrometry (EDS) were: 15 kV voltage, 5 μm spot diameter and peak counting times of 30 s. SEM analyses were done prior to microprobe analysis so that any inclusions, localized zoning or textural characteristics present could be documented. 2.2 Electron Microprobe Major element analyses of Muskox megacrysts were carried out on both thin sections and epoxy grain mounts using an automated CAMECA SX-50 electron-microprobe at the Department of Earth and Ocean Sciences at UBC. Spots were analyzed using an accelerating voltage of 15 kV, a 20 nA beam current, a beam diameter of 5 µm, an on-peak counting time of 20 seconds and background-count time of 10 seconds. Individual samples were analyzed on five to ten points within unzoned regions of both cores and rims. Individual measurements have been averaged together for samples that are chemically homogeneous. All measurements and minimum detection limits (MDLs) are listed in Appendix B. Localized zoning along grain fractures was observed within a small number of ilmenite samples, however these areas only displayed a maximum discrepancy of ± 0.2 wt.% FeOT and are therefore included in averages. 202.3 Trace Element LA-ICP-MS Clinopyroxene trace element analyses were carried out using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) utilizing an ArF excimer laser ablation system (193 nm; Resolution M-50LR, ASI Australia) coupled with a Quadrupole ICP-MS at the Pacific Center for Isotopic and Geochemical Research (PCIGR) at UBC. Measurements were performed at a repetition rate of 8 Hz using a laser spot size of 89 μm. Energy density on each sample was 1.8 J/cm2. Helium was used as the carrier gas admixed with argon prior to introduction the IPC-MS, with a small amount of N2 downstream from the ablation cell for signal stabilization. The mass spectrometer was tuned to maximize sensitivity while minimizing oxide production to ThO/Th < 0.3%. The mass bias was 95% < 238U/232Th < 105%. Each sample was ablated for 40 s after a short pre-ablation to remove surface contaminants, followed by a 30 s washout for background correction as described in Ver Hoeve et al. (2018) and Fourny et al. (2020). Calibration was carried out by standard bracketing using the synthetic silicate glass NIST SRM 612 as external standard and Ca (43) as internal standard using values from microprobe analyses (reported in Table 4.1). NIST SRM 610 and USGS basalt reference material BCR2-G were cross-checked for quality control. Data reduction was performed using the Iolite 3.0 software (Paton et al. 2011). Non-averaged measurements and errors for all samples are listed in Appendix C. 2.4 in situ Pb isotopes For isotopic analyses we selected clinopyroxenes from high-Cr and low-Cr megacrysts, websterites, peridotite xenoliths with primary or secondary clinopyroxenes and whole-rock samples of Muskox and Jericho kimberlite. All isotopic sample preparation and measurements were conducted at PCIGR. In situ Pb isotope analyses were carried out on a RESOlution M-50-21LR ArF 193 nm excimer laser connected to a Nu Instruments AttoM single collector high-resolution (HR) sector field ICP-MS using a 120 μm spot size at a repetition rate of 8 Hz and an energy density of 2 J/cm2. Samples were pre-ablated to clean surfaces, followed by a 40 s ablation and 30 s washout time for background correction (Fourny et al. 2020). Helium was used as carrier gas at a flow of 1 L/min admixed with 0.006 L/min N2 and variable Ar (approximately 0.5 L/min) prior to introduction into the ICP-MS. Masses were collected for 204Pb, 206Pb, 207Pb and 208Pb in ‘Deflector Jump’ mode. 202Hg was monitored to correct for isobaric interference of 204Hg on 204Pb measurements, however 204Pb ratios are not reported due to unfavorable signal-to-noise ratio resulting from high (>100) Hg background counts, likely originating from plastic components inside the ICP-MS. Calibration was carried out using standard bracketing with NIST SRM612 (Jochum et al. 2005) as the reference material. Data reduction was performed using Iolite 3.0 (Paton et al. 2011). Reported Pb measurements have not been corrected for radiogenic Pb as trace element analyses revealed U and Th concentrations that were at, or below minimum detection limits for LA-ICP-MS, suggesting negligible radiogenic ingrowth after crystallization (Table 4.4). Individual measurements and 2s errors are listed in Appendix D. 2.5 Sr-Nd-Pb Isotopes Sample preparation for clinopyroxene Sr-Nd-Pb isotope analyses involved crushing samples in a mortar and pestle, followed by picking clear, inclusion-free grains under a binocular microscope to be powdered in an agate mortar. For whole-rock kimberlite, sections of drillcore were crushed and chips free of xenolithic and xenocrystic material were selected and powdered using the same technique. Hotplate digestion of clinopyroxene powders was carried out utilizing the protocol described in Weis et al. (2006) for mafic samples, involving the use of HF and HNO3 22as primary acids, in addition to HCl for the removal of any remaining volatiles and precipitates. Kimberlite powders required high-pressure PTFE bomb digestion using the HF-HNO3-HClO4 digestion method of Pretorius et al. (2006). After digestion, all aliquots underwent ion exchange chromatography to separate Pb, Nd and Sr following the method described in Weis et al. (2006) and Fourny et al. (2016). Pb and Nd isotopic measurements were carried out using a Nu Instruments Nu Plasma II multi-collector ICP-MS, while Sr isotopes were measured on a Nu thermal ionization mass spectrometer (TIMS). AGV-2, BCR-2 and G-3 were used as reference materials for all isotopic analyses, the concentrations and 2s errors for which are reported in Table 4.4. Trace elements were measured on an Element II HR-ICP-MS using AVG-1, AVG-2, G-3 and BCR-2 as reference materials. 23Chapter 3 Samples & Petrography 3.1 The Muskox and Jericho Kimberlites The Muskox kimberlite belongs to a mid-Jurassic (172.1 ± 2.4 Ma; Hayman et al. 2009) kimberlite cluster that also includes the Jericho pipes (15 km northeast) emplaced into granite-granodiorite within the north-central Slave craton in Nunavut, Canada. The petrologic and petrographic characteristics of both the Muskox and Jericho kimberlites have been described previously by Kopylova and Hayman (2008) and Hayman et al. (2009) respectively. 3.2 Petrography of Clinopyroxene Megacrysts Clinopyroxene megacrysts range in size from 10 mm to 22 mm in maximum dimension (Appendix A). Samples are unzoned, monocrystalline, heavily fractured and cylindrical to ellipsoid in shape with larger samples (>20 mm) having more rounded shapes. Rounded morphologies suggest megacrysts likely represent fragments of larger discrete grains that underwent resorption and/or physical abrasion during kimberlite ascent. A majority of samples contain reaction rims where in contact with the host kimberlite, further indicating reaction during ascent (Fig. 3.1). Energy dispersive X-ray spectroscopy (EDS) revealed these rims contain elevated Fe, Ba, Mg and Na contents relative to clinopyroxene. These grain boundaries are often accompanied by fractures and vein networks infilled by kimberlite groundmass. Nearly all samples display “spongy” zones that occur in broadly linear trends (Fig. 3.2), previously ascribed to reactions between mantle minerals and kimberlitic melt (Bussweiler et al. 2016). Clinopyroxene frequently contains inclusions of both strontianite and phlogopite (Fig. 3.2), as well as minor amounts of secondary barite (Fig. 3.3). 24 Fig. 3.1 Clinopyroxene megacryst with serpentine and melt reaction rims where in contact with kimberlite. Fig. 3.2 Clinopyroxene megacryst with inclusion of both phlogopite (dark gray) and carbonate (white) localized within a region of “spongy” texture. 25 Fig. 3.3 Clinopyroxene megacryst with secondary barite (white) localized within a fracture. Fig. 3.4 Polycrystalline olivine megacryst with serpentine (dark gray) between grains with accumulations of Fe-Ti oxides (white). 263.3 Petrography of Garnet Megacrysts Despite garnet being a common megacryst phase at other localities (e.g. Pivin et al. 2009), only two samples were recovered at Muskox. Samples range in size from 10 mm up to 25 mm and are sub-rounded in shape, indicating resorption within the host kimberlite similar to clinopyroxene (Appendix A). Samples are unzoned, free of inclusions, dark red in color and either polycrystalline or monocrystalline. 3.4 Petrography of Olivine Megacrysts Olivine megacrysts range from 10 mm to 18 mm in maximum dimension. Olivine is either polycrystalline or heavily fractured (Appendix A). Polycrystalline samples contain serpentine infilling between individual grain boundaries with accumulations of Fe-Ti oxides (Fig. 3.4). Olivine lacks many of the traits exhibited by other megacryst phases, including spongy zones, reaction rims, and inclusions. 3.5 Petrography of Ilmenite Megacrysts Ilmenite megacrysts range in size from 10 mm to 39 mm in maximum dimension (Appendix A). Samples are cylindrical to round/ameboid in shape are significantly rounded along grain boundaries, again, attributable to kimberlitic resorption. Ilmenite megacrysts contain reaction rims similar to those observed in clinopyroxene where the grain is in contact with kimberlite (Fig. 3.5). EDS show these rims are more magnesian and aluminous than the ilmenite they surround. While ilmenites contain no inclusions, they frequently contain possess perovskite and leucoxene as alteration products in association with serpentine (Fig. 3.6). Secondary barite is 27 Fig. 3.5 Mg and Al-rich reaction rim between ilmenite megacryst and host kimberlite. Fig. 3.6 Ilmenite megacryst displaying alteration to perovskite (white) and leucoxene (dark gray) localized near veins of serpentine (black). 28also present in some samples, though only very minor amounts. No lamella exsolution features were observed in any megacryst samples. 3.6 Petrography of Polymineralic Megacrysts Three samples differed from the majority of the sample suite in that they were not discrete megacrysts. Rather, these samples were megacrysts either intergrown with or surrounded by additional phases. The first polymineralic sample, MOX-24-240.2, is a sub-rounded ilmenite megacryst with intergrown megacrystic clinopyroxene measuring 39 mm by 23 mm in maximum dimension (Appendix A). SEM analysis revealed small inclusions of carbonate, phlogopite, and minor amounts of both barite and apatite within the clinopyroxene intergrowths of the sample (Fig. 3.7), however no inclusions were observed in ilmenite. Ilmenite contains the same vein networks locally altering to perovskite and leucoxene observed in previous ilmenite megacrysts. Very minor localized zoning was present in ilmenite, noted for microprobe analysis. MOX-24-230.7, is a megacrystal intergrowth comprised of equal volumes of garnet and clinopyroxene. The portion of the sample recovered from the drillcore measures 26 mm by 24 mm (Appendix A), however the sample is presumed to originally be significantly larger, as only a small corner of the grain was intercepted at the edge of the drillcore. Kimberlite groundmass infills fractures with groundmass comprised of chromite and phlogopite where in contact with silicate megacryst phases (Fig. 3.8). The final polymineralic sample, MOX-24-42.6, is an olivine megacryst enveloped by a websteritic assemblage comprised of orthopyroxene, clinopyroxene and minor olivine and garnet (Appendix A). The megacryst itself contains no inclusions, however inclusions of carbonate are 29 Fig. 3.7 Clinopyroxene in polymineralic megacryst sample MOX-24-240.2 with inclusions of both phlogopite and apatite localized near areas of serpentinization. Fig 3.8 Area of serpentinization in MOX-24-230.7 with both phlogopite and chromite. 30present within websteritic clinopyroxene, as well as phlogopite in areas of serpentine and associated Fe-Ti oxide alteration (Fig. 3.9). 3.7 Petrography of Muskox Xenoliths Clinopyroxene megacrysts in this study have been chemically and isotopically compared with clinopyroxene from both coarse peridotite and websterite xenoliths from the Muskox kimberlite, previously described by Newton et al. (2015). Clinopyroxene in coarse peridotite is present in minor amounts (<5 vol. %) either as primary or metasomatic grains. Primary clinopyroxene appears texturally equilibrated with surrounding phases (Fig. 3.10a, b), in addition to being present in significantly lower abundances (<1 vol. %) relative to metasomatic clinopyroxene (≥5 vol. %). The latter occurs in wormlike grains along grain boundaries, often enveloping other minerals (Fig. 3.10c), or in olivine-clinopyroxene clusters as small subhedral to euhedral grains (Fig. 3.10d). Websterites have coarse allotriomorphic textures with clinopyroxene forming networks of subhedral to anhedral irregularly shaped grains intergrown with roughly equal volumes of orthopyroxene (Figs. 3.10e, f). 31 Fig. 3.9 MOX-24-42.6 with inclusions of both carbonate and phlogopite in clinopyroxene occurring near serpentine pseudomorphs. Fe-oxide accumulation (white) visible on contacts between serpentine and olivine. 32 Figure 3.10. Photomicrographs of Muskox xenoliths. (a & b) Primary clinopyroxene in peridotite MOX-3-33.0 (PPL), (c) metasomatic clinopyroxene in peridotite MOX-31-224.5 (PPL), (d) metasomatic clinopyroxene in peridotite MOX-7-62.3 (PPL), (e) clinopyroxene in websterite MOX-24-206.7 (XPL) and (f) clinopyroxene in websterite MOX-24-42.6 (XPL). 33Chapter 4 Results 4.1 Major & Trace Element Compositions of Clinopyroxene Clinopyroxene (Di80-85Jd05-08Hd08-10Kos01-04) can be classified into two distinct suites based on Cr2O3 contents: high-Cr (0.68-1.5 wt.%) and low-Cr (0.45-0.63 wt.%; Table 4.1). The threshold between suites is analogous to megacrysts from the Jericho kimberlite (Kopylova et al. 2009), but lower than the threshold for megacrysts outside of the Slave craton (Pivin et al. 2009). High-Cr clinopyroxene is distinguished by higher Ti, Na and Al contents, yet shows Ca depletion relative to the low-Cr suite, contrasting the behavior in megacrysts from other localities (Eggler et al. 1979; Pivin et al. 2009). Cr and Na contents in clinopyroxene show strong positive correlations, while Cr and Ca display a strong negative correlation (Fig. 4.1a, b). High-Cr clinopyroxene overlaps the compositional field of websteritic clinopyroxene and extends to overlapping fields for clinopyroxene from both porphyroclastic and coarse peridotite xenoliths from the Muskox kimberlite (Fig. 4.1a). The Cr-Ca trend defined by the low-Cr and high-Cr megacrystal fields is extrapolated to the trend observed in websterites (grey line in Fig. 4.1a) and is unlike the Cr-Ca relationships in Muskox peridotites. Low-Cr clinopyroxene does not correlate with any previously reported compositions from Muskox xenoliths (Fig. 4.1a). Samples overlap with data for global megacrysts and possess a similar compositional trend with megacrysts from Jericho (Fig. 4.1b), however are more Ca-rich. Measured trace element concentrations for clinopyroxene megacrysts (Table 4.2) are compared with analogous data for xenoliths and kimberlite listed in Table 4.3. Clinopyroxenes show uniform trace element patterns with LREE enrichments of between 12- and 19-times chondrite (McDonough and Sun 1995) and HREE concentrations between 0.4- and 5-times chondrite (Fig. 4.2). Websteritic clinopyroxenes have REE patterns that are parallel to megacrysts, 34 Fig. 4.1 Cr2O3-CaO (wt. %) in high-Cr (black dots) and low-Cr (red dots) clinopyroxene megacrysts. Our data have been compared with clinopyroxene from websterite (green field), coarse peridotite (grey field) and porphyroclastic peridotite (purple field) xenoliths from Muskox (a; Newton et al. 2015). Global megacryst data (b) are from the Jericho kimberlite (Kopylova et al. 2009) and the Lac de Gras kimberlites (Bussweiler et al. 2018). Fig. 4.2 Chondrite-normalized (McDonough and Sun 1995) REE patterns for Muskox clinopyroxene megacrysts (black squares) compared with clinopyroxenes from Muskox peridotite (purple triangles) and websterite (green stars) xenoliths analyzed via LA-ICP-MS prior to isotopic analyses. 0.0010.010.1110100La Ce Pr Nd Sm Eu Gd Tb Dy Ho Er Tm Yb LuSample/chondriteWebsteritePeridotitea.MegacrystMOX-7-62.3MOX-3-33.035Sample Mineral Suite Average of SiO2, wt% TiO2, wt% Al2O3,wt% Cr2O3, wt% FeOT, wt% MnO, wt% MgO, wt% CaO, wt% Na2O, wt% NiO, wt% Nb2O5, wt% TotalMUSK-3-202.4 Clinopyroxene High-Cr 16 54.80 0.24 1.82 1.06 3.47 0.11 17.36 19.80 1.68 bd na 100.35MOX-24-124A Clinopyroxene High-Cr 24 54.70 0.26 1.93 1.28 3.32 0.11 17.21 19.70 1.83 0.10 na 100.44MUSK-3-158.8 Clinopyroxene High-Cr 10 54.41 0.24 1.95 0.77 3.28 0.11 17.01 20.80 1.63 bd na 100.20MUSK-3-198.37 Clinopyroxene High-Cr 10 54.08 0.25 1.95 1.00 3.35 0.10 17.03 20.04 1.74 bd na 99.55MOX-24-34.3 Clinopyroxene High-Cr 10 54.24 0.23 1.88 1.28 3.20 0.11 17.27 19.77 1.77 bd na 99.75MOX-28-320.1 Clinopyroxene High-Cr 10 54.79 0.25 1.89 0.95 3.34 0.10 17.17 20.42 1.66 0.09 na 100.67MOX-25-161.5C Clinopyroxene High-Cr 10 54.28 0.27 2.01 1.31 3.34 0.11 17.08 19.37 1.87 bd na 99.65MOX-24-209.7 Clinopyroxene Low-Cr 10 54.43 0.19 1.57 0.49 3.21 0.11 16.90 21.77 1.40 bd na 100.06MOX-1-43.35 Clinopyroxene Low-Cr 10 54.18 0.19 1.62 0.56 3.25 0.11 16.91 21.75 1.35 bd na 99.93MOX-24-230.7 Garnet High-Cr 10 40.85 0.64 19.60 4.71 9.71 0.49 19.17 5.14 0.09 na na 100.41MOX-25-124.8 Garnet Low-Cr 10 41.82 0.19 22.57 0.84 8.88 0.20 19.42 5.95 bd na na 99.87MOX-24-206.97 Ilmenite Low-Cr 15 bd 52.47 0.11 2.43 31.88 0.29 12.16 0.04 na na 0.18 99.38MOX-24-209.7 Ilmenite Low-Cr 10 0.06 52.64 0.14 2.01 32.21 0.27 11.97 0.04 na na 0.18 99.34MOX-28-308 Ilmenite Low-Cr 15 0.07 52.33 0.12 2.94 31.15 0.27 12.39 0.04 na na 0.16 99.32MOX-3-74.4 Ilmenite Low-Cr 15 0.06 52.51 0.15 2.25 31.89 0.32 12.20 0.07 na na 0.19 99.45MOX-25-65.16 Ilmenite Low-Cr 15 bd 51.60 bd 1.66 34.33 0.33 11.27 0.04 na na 0.23 99.24MOX-24-206.73 Ilmenite Low-Cr 10 bd 51.97 bd 1.60 33.96 0.32 11.53 0.06 na na 0.22 99.43MOX-25-120.6A Ilmenite Low-Cr 15 bd 51.87 bd 1.63 34.16 0.33 11.24 bd na na 0.24 99.22MOX-24-24.2 Ilmenite Low-Cr 10 bd 52.71 bd 3.12 30.51 0.27 12.98 0.02 na na bd 99.61MOX-24-102.8 Olivine Low-Cr 10 40.85 0.06 bd 0.08 9.93 0.12 49.67 0.04 na 0.35 na 101.10MOX-25-161.5G Olivine Low-Cr 10 40.61 0.05 bd 0.06 10.55 0.11 48.91 0.05 na 0.28 na 100.61MOX-24-42.6 Olivine Low-Cr 4 40.66 0.05 bd bd 10.26 0.14 49.46 0.05 na 0.31 na 100.93Oxide data for Muskox megacrysts. Cores and rims of all samples are averaged together. bd indicates measurements that were below minimum detection limits. na indicates oxides not analyzedTable 4.1. Major element compositions of Muskox megacrysts36Sample MOX-24-124A SD MOX-24-209.7 SD MOX-28-320.1 SD MOX-1-43.35 SD MOX-25-161.5C SD MUSK-3-202.4 SD MOX-24-34.3 SD MUSK-3-158.8 SD MUSK-3-198.37 SDRb 0.06 0.02 0.15 0.01 0.01 0.01 - 0.00 0.01 0.01 0.04 0.02 0.01 0.01 - 0.00 0.01 0.01Sr 182 2.23 189 3.40 174 2.12 199 3.10 177 2.66 167 1.90 169 2.44 189 2.20 178 3.28Ba 0.7 0.32 0.6 0.27 0.2 0.15 0.27 0.08 0.4 0.15 0.4 0.29 0.29 0.08 0.25 0.07 0.47 0.10Nb 0.39 0.03 0.33 0.03 0.32 0.03 0.29 0.02 0.36 0.03 0.41 0.03 0.27 0.02 0.30 0.02 0.30 0.03Ta 0.03 0.01 0.03 0.01 0.03 0.01 0.02 0.01 0.03 0.01 0.03 0.01 0.02 0.01 0.03 0.01 0.02 0.01La 3.05 0.08 2.73 0.08 2.71 0.07 2.98 0.08 2.83 0.08 2.89 0.07 2.47 0.07 2.93 0.06 2.77 0.07Ce 10.5 0.19 10.5 0.25 9.6 0.16 11.4 0.24 10.3 0.20 10.0 0.16 8.9 0.17 10.5 0.16 10.9 0.25Pr 1.68 0.05 1.66 0.05 1.54 0.05 1.77 0.05 1.65 0.06 1.63 0.05 1.41 0.05 1.72 0.05 1.69 0.06Nd 8.4 0.28 7.9 0.30 7.6 0.28 8.5 0.27 8.4 0.31 7.9 0.26 6.9 0.26 8.5 0.26 8.2 0.29Sm 1.9 0.14 1.8 0.14 1.7 0.14 1.8 0.12 1.9 0.15 1.8 0.13 1.5 0.12 1.9 0.13 1.8 0.13Eu 0.55 0.04 0.54 0.04 0.49 0.04 0.51 0.03 0.58 0.04 0.50 0.04 0.45 0.04 0.55 0.03 0.52 0.04Gd 1.5 0.12 1.3 0.11 1.3 0.11 1.3 0.10 1.6 0.12 1.3 0.10 1.2 0.10 1.4 0.11 1.3 0.10Tb 0.17 0.02 0.15 0.01 0.15 0.02 0.14 0.01 0.18 0.02 0.16 0.01 0.13 0.01 0.17 0.01 0.16 0.01Dy 0.84 0.07 0.72 0.07 0.69 0.07 0.64 0.06 0.89 0.08 0.81 0.07 0.66 0.06 0.78 0.06 0.73 0.06Ho 0.12 0.01 0.11 0.01 0.10 0.01 0.09 0.01 0.13 0.02 0.12 0.01 0.10 0.01 0.11 0.01 0.11 0.01Er 0.26 0.03 0.20 0.03 0.20 0.03 0.18 0.03 0.26 0.04 0.21 0.03 0.19 0.03 0.21 0.03 0.21 0.03Tm 0.02 0.01 0.016 0.00 0.02 0.01 0.016 0.00 0.03 0.01 0.021 0.00 0.018 0.00 0.022 0.00 0.021 0.00Yb 0.13 0.03 0.10 0.03 0.10 0.02 0.08 0.02 0.12 0.03 0.11 0.02 0.08 0.02 0.10 0.02 0.10 0.02Lu 0.015 0.00 0.010 0.00 0.011 0.00 - 0.00 0.02 0.01 - 0.00 - 0.00 0.012 0.00 0.011 0.00Y 2.79 0.08 2.25 0.07 2.31 0.07 2.07 0.06 2.98 0.09 2.57 0.07 2.14 0.07 2.45 0.07 2.46 0.07Zr 13.7 0.29 15.8 0.35 13.5 0.28 15.0 0.29 14.9 0.34 12.5 0.25 10.4 0.27 14.7 0.28 13.9 0.30Hf 1.02 0.08 1.1 0.10 0.95 0.08 1.01 0.07 1.02 0.09 0.92 0.07 0.72 0.07 1.06 0.07 0.95 0.08Pb 0.45 0.02 0.44 0.02 0.48 0.02 0.49 0.02 0.41 0.02 0.43 0.02 0.42 0.02 0.45 0.02 0.44 0.02Concentrations lower than 0.01 are indicated with a \"-\". Standard deviation (SD) is 2σTable 4.2. Trace element concentrations (ppm) of clinopyroxne megacrysts (LA-ICP-MS)37Sample MOX-25-161.5c-KIM MOX-24-43.35-KIM LGS-010-456' LGS-010-456'-dup LGS-010-456'-rep MOX-3-33.0 MOX-7-30.02 MOX-24-42.6 MOX-24-206.7 MOX-7-62.3 MOX-31-224.5Sample Type Muskox Kimberlite Muskox Kimberlite Jericho KimberliteJericho Kimberlite (duplicate)Jericho Kimberlite (replicate)Primary peridotitic clinopyroxeneWebsteritic clinopyroxeneWebsteritic clinopyroxeneWebsteritic clinopyroxeneSecondary peridotitic clinopyroxeneSecondary peridotitic clinopyroxeneMeasured via: HR-ICP-MS HR-ICP-MS HR-ICP-MS HR-ICP-MS HR-ICP-MS HR-ICP-MS HR-ICP-MS HR-ICP-MS LA-ICP-MS LA-ICP-MS LA-ICP-MSRb 63.6 76.6 16.2 16.9 16.1 2.42 6.80 3.24 0.114 - -Sr 692 1148 704 712 704 1110 186 149 10.3 8.5 9.3Ba 2037 2468 1999 2073 1980 32.1 52.6 49.0 1.69 0.031 0.112Nb 118 113 206 210 202 1.77 3.95 2.42 0.168 0.122 - Ta 9.2 8.4 15.5 16.0 15.9 0.064 0.148 0.132 - - -La 92 86 117 120 115 30.1 7.96 4.02 0.259 0.251 0.182Ce 149 133 204 212 206 83.0 16.8 9.7 0.67 0.58 0.58Pr 14.0 12.8 19.3 19.8 19.1 11.3 2.25 1.42 0.101 0.058 0.087Nd 47.1 43.4 63.6 65.9 63.3 44.3 9.2 6.25 0.48 0.174 0.42Sm 5.50 5.12 7.58 7.72 7.39 3.98 1.67 1.33 0.101 0.020 0.093Eu 1.44 1.34 1.84 1.87 1.76 0.776 0.501 0.409 0.028 - 0.027Gd 3.11 2.72 4.25 4.22 4.18 1.16 1.25 1.03 0.076 0.010 0.070Tb 0.318 0.275 0.440 0.438 0.419 0.084 0.144 0.129 - - -Dy 1.28 1.14 1.78 1.79 1.76 0.243 0.582 0.561 - - 0.040Ho 0.188 0.163 0.246 0.242 0.220 0.033 0.085 0.084 - - -Er 0.475 0.387 0.549 0.540 0.525 0.066 0.170 0.170 - - 0.011Tm 0.063 0.049 0.064 0.063 0.061 - 0.019 0.019 - - -Yb 0.360 0.282 0.354 0.343 0.341 0.034 0.093 0.095 - - -Lu 0.052 0.040 0.047 0.047 0.046 - 0.012 0.011 - - -Y 5.10 4.16 6.26 6.19 6.04 0.703 1.93 1.88 0.141 0.022 0.132Zr 50.8 49.0 81.4 83.2 80.9 5.31 11.4 8.15 0.77 0.061 0.62Hf 1.28 1.19 2.18 2.18 2.13 0.197 0.672 0.550 0.044 - 0.040Pb 7.81 11.2 10.8 10.1 10.6 5.87 0.746 0.490 0.063 0.078 0.040Concentrations below 0.01 are indicated with a \"-\". Average RSD for HR-ICP-MS runs was 1.2%. Average RSD for LA-ICP-MS runs was 2.5%\"replicate\" indicates a replicate measurement of the same sample. \"duplicate\" indicates a procedural duplicate of the same sampleTable 4.3. Trace element concentrations of websteritic clinopyroxene, peridotitic clinopyroxene and whole-rock kimberlite via LA-ICP-MS (ppm) and HR-ICP-MS (µg/g)38often with identical concentrations (Fig. 4.2a). Websterite MOX-24-206.7 has concentrations approximately an order of magnitude lower than the range of other websterites but is indistinguishable from metasomatic clinopyroxene in peridotite sample MOX-31-224.5. The remaining metasomatic clinopyroxene MOX-7-62.3 has LREE concentrations similar to these two samples, but significantly higher degrees of HREE fractionation. Primary clinopyroxene in peridotite has LREE concentrations just below megacrysts and most websterites but becomes extremely fractionated in MREE’s and HREE’s. 4.2 Major Element Compositions of Garnet Garnets (Py67-69Grs13-16Alm17-20) span a narrow range of Mg# (77.1-80.0; mole Mg/(Mg+Fe)x100) with highly variable Cr2O3 contents ranging from 0.47-1.12 wt.% in the low-Cr suite and 4.34-5.50 wt.% in the high-Cr suite (Table 4.1). High-Cr garnets display an enrichment in Fe and Ti with a depletion in Al relative to the low-Cr suite. Neither suite corresponds with existing xenolith data from the Jericho kimberlite (Fig. 4.3a) but have compositions typical of worldwide megacryst occurrences (Fig. 4.3b). 4.3 Major Element Compositions of Olivine Olivine is forsterite with Mg# ranging from 88.9 to 90.2 (Table 4.1). These values are similar to the range of both Muskox websterite and Jericho olivine megacrysts but are slightly lower than olivine from both coarse and porphyroclastic peridotites at Muskox and Jericho (Kopylova et al. 2009; Newton et al. 2015), as well as kimberlitic olivine from the Slave mantle as sampled by Lac de Gras (Fig. 4.4). 39 Fig. 4.3 Cr2O3-TiO2 (wt. %) in high-Cr (black dots) and low-Cr (red dots) garnet megacrysts. (a) Our data have been compared with garnet from websterite (green field), coarse peridotite (grey field) and porphyroclastic peridotite (purple field) xenoliths from Jericho (Kopylova et al. 1999). (b) Global megacryst data are from the Jericho kimberlite (Kopylova et al. 2009) and the Lac de Gras kimberlites (Bussweiler et al. 2018). Fig. 4.4 NiO-Mg# (100xMg/(Mg+Fe) moles) in olivine megacrysts compared with kimberlitic olivine core (dashed fields) and rim (solid fields) data from the Slave craton (Fedortchouk & Canil 2004; Brett et al. 2009; Bussweiler et al. 2015). 404.4 Major Element Compositions of Ilmenite Ilmenite megacrysts (Ilm55-64Gk36-45) have variable concentrations of both Cr2O3 (1.47-4.62 wt.%) and FeOT (29.2-34.8 wt.%; Table 4.1) and belong entirely to the low-Cr suite as suggested by Eggler et al. (1979), as the Cr contents in low-Cr garnet and clinopyroxene are buffered by Cr in ilmenite (Kopylova et al. 2009). Samples from Muskox plot within the field occupied by Jericho megacrysts and display a nearly identical range of both Cr2O3 and MgO contents (Fig. 4.5). Fig. 4.5 Cr2O3-MgO (wt. %) in ilmenite megacrysts. Global megacryst data are from the Jericho kimberlite (Kopylova et al. 2009), Grib kimberlite (Kostrovitsky et al. 2004) and Luxinga kimberlite (Rogers & Grütter 2006). 414.5 Clinopyroxene Sr-Nd-Pb Isotopes In-situ Pb isotope measurements (Table 4.4; Appendix D) for megacrysts range from 207Pb/206Pb = 0.811-0.819 and 208Pb/206Pb = 2.023-2.053. Websterite has 207Pb/206Pb = 0.816-0.823 and 208Pb/206Pb = 2.042-2.053, making it most similar to low-Cr megacrysts (Fig. 4.6). Metasomatic clinopyroxene in peridotite has 207Pb/206Pb and 208Pb/206Pb ranging from 0.821-0.823 and 2.047-2.054 respectively, making it isotopically indistinguishable from websteritic clinopyroxene. Primary clinopyroxene has 207Pb/206Pb = 0.961 and 208Pb/206Pb = 2.272. All Pb isotopic measurements carried out via column chemistry demonstrate excellent agreement with in situ Pb data and are reported in Table 4.4 along with Nd and Sr ratios. Clinopyroxene megacrysts have Pb ratios ranging from 206Pb/204Pb = 18.865-18.986, 207Pb/204Pb = 15.581-15.618 and 208Pb/204Pb = 38.729-38.801. High-Cr megacrysts are marked by a more radiogenic signature in all Pb ratios than the single low-Cr megacryst analyzed, however is most visible in 206Pb/204Pb (Fig. 4.7). 143Nd/144Nd of megacrysts range from 0.51258-0.51261, showing a disparity of approximately 0.5 epsilon units between the high-Cr and low-Cr suites (Figs. 4.8, 4.9). Initial 87Sr/86Sr range from 0.70335-0.70492 and show a similar disparity between suites (Fig. 4.9). 87Sr/86Sr-206Pb/204Pb systematics reveal no discernable correlation (Appendix F). Websteritic clinopyroxenes display the widest range in isotopic ratios between measured samples, with 206Pb/204Pb = 18.100-19.071, 207Pb/204Pb = 15.510-15.611 and 208Pb/204Pb = 38.074-39.863 (Table 4.4). Sample MOX-24-42.6 plots near the field occupied by megacrysts and Jericho kimberlite, however MOX-7-30.02 is significantly less radiogenic and plots closer to the host kimberlite than megacrysts. Similar behavior is seen in 143Nd/144Nd values which vary significantly from 0.51236-0.51261, the largest range of all samples analyzed in this study (Figs. 4.8, 4.9). 87Sr/86Sr is remarkably restricted, ranging from 0.70336-0.70339 (Fig. 4.9). 42 Fig. 4.6 Joint in situ (dashed and dotted lines) and HR-ICP-MS 208Pb/206Pb vs. 207Pb/206Pb for Muskox and Jericho samples compared with literature data for African kimberlites (orange field; Smith 1983; Davies et al. 2001), the Nikos kimberlite (blue field; Schmidberger et al. 2001) and Gibeon megacrysts (yellow field; Davies et al. 2001). Fig. 4.7 206Pb/204Pb vs. 207Pb/204Pb isotopic compositions and mixing models. Samples are compared with data for cratonic peridotite (Schmidberger et al. 2001; Wittig et al. 2007; Liu et al. 2012), clinopyroxene from MARID (Mica-Amphibole-Rutile-Ilmenite-Diopside) and PIC (Phlogopite-Ilmenite-Clinopyroxene) xenoliths (Fitzpayne et al. 2019) and East African carbonatites (Kalt et al. 1997; Bell and Tilton 2001). Solid gray lines are the 4.55 Ga Geochron and 1 Ga model Geochron. Inset is 206Pb/204Pb vs. 208Pb/204Pb. 18.0 19.020.0 21.0206Pb/204Pb15.315.415.515.615.715.8207 Pb/204 Pb East Africancarbonatites- Primary clinopyroxene- Websteritic clinopyroxene- Muskox kimberlite- Jericho kimberlite- Clinopyroxene megacrystsMARID/PICCratonicperidotite16.0 17.01%5%GeochronEM1HIMU206Pb/204Pb18.2 18.6 19.038.238.438.638.8208 Pb/204 Pb1 Ga43 Fig. 4.8 206Pb/204Pb vs. 143Nd/144Nd for Muskox and Jericho samples compared with data for East African carbonatites (Kalt et al. 1997; Bell and Tilton 2001). Arrow points to peridotite sample MOX-3-33.0, which plots outside the boundaries of the figure. CHUR = 0.512638. 44 Fig. 4.9 87Sr/86Sr vs. 143Nd/144Nd for Muskox and Jericho samples compared with (a) existing Jericho megacryst and kimberlite data (Kopylova et al. 2009), megacrysts and kimberlite from South Africa (Nowell et al. 2004) and data for East African carbonatites (Kalt et al. 1997; Bell and Tilton 2001). BSE = 0.70445. (b) Zoomed in 87Sr/86Sr vs. 143Nd/144Nd for the same samples (less primary clinopyroxene). 45Table 4.4. Sr-Nd-Pb isotopic data for Muskox and Jericho samplesSample name Sample type Pb (ppm) 206Pb/204Pbm 2σ 207Pb/204Pbm 2σ 208Pb/204Pbm 2σ 206Pb/204Pbi 207Pb/204Pbi 208Pb/204Pbi µ Th/U 207Pb/206Pb* 2σ* 208Pb/206Pb* 2σ*AGV-2 Reference material 13.3 18.8728 0.0007 15.6178 0.0006 38.5485 0.0017BCR-2 Reference material 10.1 18.7665 0.0009 15.6256 0.0009 38.7529 0.0022G-3 Reference material 29.7 18.4449 0.0011 15.6372 0.0009 38.8659 0.0026LGS-010-456’ Jericho kimberlite 10.8 20.0040 0.0009 15.6799 0.0007 40.0580 0.0019 19.227 15.641 38.983 28.6 4.38LGS-010-456’ (replicate) Jericho kimberlite 10.1 20.0033 0.0009 15.6799 0.0008 40.0573 0.0022 19.171 15.639 38.898 30.6 4.41LGS-010-456’ (duplicate) Jericho kimberlite 10.6 20.0618 0.0010 15.6824 0.0010 40.1737 0.0025 19.278 15.644 39.062 28.8 4.49MOX-1-43.35-KIM Muskox kimberlite 11.2 18.8806 0.0009 15.5684 0.0008 39.0739 0.0024 18.466 15.548 38.739 15.2 2.56MOX-1-43.35-KIM (replicate) Muskox kimberlite 11.2 18.8786 0.0009 15.5661 0.0007 39.0689 0.0018 18.464 15.546 38.734 15.2 2.56MOX-25-161.5c-KIM Muskox kimberlite 7.81 19.1235 0.0010 15.5845 0.0007 39.3900 0.0021 18.509 15.554 38.692 22.6 3.59MOX-1-43.35 Low-Cr megacryst 0.561 19.0065 0.0006 15.5880 0.0006 39.0327 0.0015 18.865 15.581 38.730 5.19 6.79 0.819 0.016 2.053 0.035MUSK-3-158.8 High-Cr megacryst 0.495 18.9792 0.0012 15.6207 0.0009 38.8299 0.0027 18.932 15.618 38.743 1.73 5.83 0.811 0.017 2.023 0.035MUSK-3-158.8 (replicate) High-Cr megacryst 0.495 18.9771 0.0010 15.6192 0.0009 38.8264 0.0023 18.930 15.617 38.740 1.73 5.83MOX-25-161.5c High-Cr megacryst 0.595 19.2069 0.0007 15.5976 0.0007 39.1899 0.0017 18.985 15.587 38.801 8.15 5.56 0.811 0.017 2.053 0.035MOX-7-30.02 Websteritic clinopyroxene 0.746 18.3501 0.0009 15.5227 0.0009 38.3395 0.0022 18.100 15.510 38.074 9.19 3.36 0.816 0.018 2.042 0.050MOX-24-42.6 Websteritic clinopyroxene 0.490 19.2197 0.0015 15.6090 0.0008 39.1092 0.0023 19.071 15.602 38.863 5.48 5.22 0.822 0.015 2.052 0.033MOX-24-206.7 Websteritic clinopyroxene 0.063 0.823 0.010 2.053 0.020MOX-3-33.0 Peridotitic clinopyroxene 5.87 16.1652 0.0007 15.3207 0.0006 36.4857 0.0016 16.104 15.318 36.378 2.27 5.54 0.961 0.010 2.272 0.022MOX-7-62.3 Metasomatic clinopyroxene 0.078 0.823 0.008 2.054 0.017MOX-31-224.5 Metasomatic clinopyroxene 0.040 0.821 0.013 2.047 0.041Sample name Sample type Sm (ppm) Nd (ppm) 143Nd/144Ndm 2σ 143Nd/144Ndi εNdi 147Sm/144NdAGV-2 Reference material 5.48 30.8 0.512794 0.000004BCR-2 Reference material 6.61 28.9 0.512644 0.000006G-3 Reference material 7.31 54.6 0.512243 0.000005LGS-010-456’ Jericho kimberlite 7.58 63.6 0.512647 0.000004 0.51257 2.94 0.0720LGS-010-456’ (replicate) Jericho kimberlite 7.72 65.9 0.512640 0.000005 0.51256 2.82 0.0708LGS-010-456’ (duplicate) Jericho kimberlite 7.39 63.3 0.512643 0.000006 0.51256 2.89 0.0706MOX-1-43.35-KIM Muskox kimberlite 5.12 43.4 0.512494 0.000006 0.51241 -0.04 0.0713MOX-1-43.35-KIM (replicate) Muskox kimberlite 5.12 43.4 0.512494 0.000005 0.51241 -0.04 0.0713MOX-25-161.5c-KIM Muskox kimberlite 5.50 47.1 0.512493 0.000005 0.51241 -0.04 0.0705MOX-1-43.35 Low-Cr megacryst 1.41 6.95 0.512719 0.000007 0.51258 3.22 0.1227MUSK-3-158.8 High-Cr megacryst 1.37 6.08 0.512762 0.000006 0.51261 3.74 0.1365MUSK-3-158.8 (replicate) High-Cr megacryst 1.37 6.08 0.512762 0.000006 0.51261 3.74 0.1365MOX-25-161.5c High-Cr megacryst 1.54 7.27 0.512754 0.000007 0.51261 3.78 0.1280MOX-7-30.02 Websteritic clinopyroxene 1.67 9.16 0.512489 0.000006 0.51236 -1.00 0.1101MOX-24-42.6 Websteritic clinopyroxene 1.33 6.25 0.512757 0.000007 0.51261 3.84 0.1286MOX-3-33.0 Peridotitic clinopyroxene 3.98 44.3 0.511294 0.000007 0.51123 -23.09 0.0543Sample name Sample type Rb ppm Sr ppm 87Rb/86Sr 87Sr/86Srm 2σ 87Sr/86SriAGV-2 Reference material 66.8 671 0.288436 0.703955 0.000008BCR-2 Reference material 46.3 333 0.402213 0.705001 0.000006G-3 Reference material 167 483 1.004075 0.709980 0.000007LGS-010-456’ Jericho kimberlite 16.2 704 0.066454 0.704522 0.000007 0.70436LGS-010-456’ (duplicate) Jericho kimberlite 16.9 712 0.068658 0.704521 0.000006 0.70435MOX-1-43.35-KIM Muskox kimberlite 76.6 1148 0.193087 0.704367 0.000007 0.70389MOX-25-161.5c-KIM Muskox kimberlite 63.6 692 0.265897 0.705189 0.000007 0.70453MOX-1-43.35 Low-Cr megacryst 3.90 311 0.036327 0.705011 0.000010 0.70492MUSK-3-158.8 High-Cr megacryst 0.296 142 0.006019 0.703368 0.000009 0.70335MOX-25-161.5c High-Cr megacryst 3.59 300 0.034680 0.704316 0.000008 0.70423MOX-7-30.02 Websteritic clinopyroxene 6.80 186 0.105604 0.703915 0.000009 0.70366MOX-24-42.6 Websteritic clinopyroxene 3.24 149 0.062868 0.703550 0.000008 0.70340MOX-3-33.0 Peridotitic clinopyroxene 2.42 1110 0.006317 0.703697 0.000007 0.70368CHUR = 143Nd/144Nd = .512638, 147Sm/144Nd = .1967\"replicate\" indicates a replicate MC-ICPMS or TIMS measurement of the same sample. \"duplicate\" indicates a procedural duplicate of the same sample* = average in-situ measurements via LA-ICP-MS. Only ratios normalzed to 206Pb are reported. These measurements have not been age-corrected for radiogenic Pb46Primary clinopyroxene in peridotite MOX-3-33.0 has a 206Pb/204Pb of 16.104 207Pb/204Pb of 15.317 and 208Pb/204Pb of 36.377 (Table 4.4), straying significantly from the field occupied by all other samples (Fig. 4.7). The same is true with 143Nd/144Nd = 0.51123, which is dramatically lower than all other samples analyzed (Figs. 4.8, 4.9). The 87Sr/86Sr for this xenolith is 0.70368, placing it near websterite MOX-7-30.02 (Fig. 4.9). Trace element systematics for this sample support a highly unradiogenic isotopic signature. Pb ratios for whole-rock Muskox kimberlite are 206Pb/204Pb = 18.464-18.509, 207Pb/204Pb = 15.546-15.554 and 208Pb/204Pb = 38.692-38.739 (Table 4.4). Whole-rock Jericho kimberlite has Pb ratios that are more radiogenic, with ranges of 19.171-19.278 for 206Pb/204Pb, 15.639-15.644 for 207Pb/204Pb and 38.898-38.983 for 208Pb/204Pb. Muskox kimberlite shows the only deviation from a strong linear trend of 208Pb/204Pb vs. 206Pb/204Pb observed for all Muskox lithologies and Jericho kimberlite (Fig. 4.7 inset). The deviation is possibly attributable to the distinctly low Th/U of the Muskox kimberlite (Table 4.4). 143Nd/144Nd for the Muskox and Jericho kimberlites are different from one another (Figs. 4.8, 4.9), ranging from 0.51241 (εNd = -0.04) for Muskox and 0.51256-0.51257 for Jericho (εNd = 2.82-2.94). 87Sr/86Sr for the two kimberlites show much more restricted range of values compared to megacrysts, ranging from 0.70389-0.70454 and 0.70435-0.70436 for Muskox and Jericho, respectively (Fig. 4.9). The widest range in values between megacrysts, websterites and kimberlite is seen in Sr ratios, which is typical of kimberlite and kimberlite-sampled material (Kopylova et al. 2009). High-Cr clinopyroxene megacrysts are most similar isotopically (as well as chemically; Table 4.1) to websteritic clinopyroxene, whereas low-Cr clinopyroxene has isotopic ratios more similar to whole-rock kimberlite (Table 4.4). The host kimberlite has significantly higher Pb, Sr, and Nd concentrations than all analyzed samples with exception of primary peridotitic clinopyroxene, potentially allowing for the reset of 47isotopic ratios in megacrysts and websterites. However, the diverse isotopic compositions recorded in megacrysts and websterites and their dissimilarity to the isotopic signature of the host kimberlite provides us confidence that the isotopic systematics of megacrysts and xenoliths have not been reset. 48Chapter 5 Deep Earth Water Modeling of Mantle Metasomatism 5.1 Modeling Methodology To determine whether megacrysts can be produced by metasomatism of mantle peridotite we employed geochemical modeling utilizing the EQ3/EQ6 aqueous speciation-solubility code of Wolery (1992) in conjunction with an updated database of equilibrium constants obtained from the Deep Earth Water (DEW) model (Sverjensky et al. 2014). This database extends the fluid-rock mass transfer modeling capabilities of EQ3/EQ6 to 6 GPa and 1000 °C making it suitable for modeling metasomatic processes at upper-mantle conditions (for a comprehensive background on DEW and its application to modeling fluid-rock reactions, see Sverjensky 2019). Three mantle-derived fluid compositions were used: kimberlitic, asthenospheric (i.e. in equilibrium with asthenospheric mantle) and eclogitic (i.e. in equilibrium with eclogite). The composition of kimberlitic fluid selected for modeling was calculated from forced multiple saturation experiments of a primary kimberlitic melt by Stamm and Schmidt (2017) under the EMOG/D (enstatite-magnetite-olivine-graphite/diamond) redox buffer. The authors report a broad range of compositions for primary kimberlite at 7 GPa and various temperatures, from which we selected an experimental composition at 1400 °C to best coincide with pressure and temperature limits of DEW. This temperature yields experimental melts with 24 wt.% SiO2 and 1.6 wt.% Al2O3, directly controlled by CO2 and H2O content, which were 16 wt.% and 7.1 wt.% respectively. The chosen contents of 8.2 wt.% FeO, 24 wt.% MgO and 13.5 wt.% CaO were based on a 50% experimental melt fraction, calculated from temperature and H2O content. The fluid was chosen to contain 2.4 wt.% Na2O as this value was an experimental minimum required to achieve 49equilibrium with high-Ca mantle clinopyroxene. Lastly, K2O was added to the fluid in the amount equal to empirically constrained K2O (1.7 wt.%) in parental, close-to-primary kimberlite melts (Becker and Le Roex 2006). The lack of existing theoretical equilibrium constants for Ti in DEW prevented inclusion of TiO2 in the fluid. After establishing these concentrations, the fluid was recalculated on an anhydrous, volatile-free basis as both CO2 and H2O were added separately as additional reactants within DEW. This anhydrous composition was then recalculated on an oxide-free basis and converted from wt.% to elemental molality. Molal concentrations of fluids before and after reactions are listed in Table 5.1. The composition of asthenospheric fluid was based on data from the experiments of Kessel et al. (2015) and was set in equilibrium with solid phases in equilibrium with a synthetic lherzolite at 5 GPa and 1000 °C (Huang and Sverjensky, 2019). The same methodology was used to calculate the composition of eclogitic fluid using data from Kessel et al. (2005) of a synthetic MORB at the same PT conditions. Fluid redox conditions were set at QFM-4 for kimberlitic, QFM-1 for asthenospheric and QFM-3 for eclogitic to ensure equilibration with experimental mineral data and agreement with fO2 estimates for both cratonic lithospheric mantle and kimberlite (Frost and McCammon 2008; Stagno et al. 2013). The composition of mantle peridotite modeled in metasomatism was derived from xenoliths from the Muskox kimberlite (Newton et al. 2015), with reduced orthopyroxene modes (5% rather than the reported 20%) to minimize the clinoenstatite end-member. Reactions utilized one of two reactant rocks: a coarse-grained garnet peridotite (“lherzolite”) comprised of 75% olivine (Fo90), 10% garnet (Py70Alm17Grs13), 10% clinopyroxene (Di84Hd07Jd09) and 5% orthopyroxene (En90), or a more fertile garnet peridotite (“fertile lherzolite”) comprised of 55% olivine, 30% clinopyroxene, 10% garnet and 5% orthopyroxene. 50Wt.% Volatile-free wt.%SiO2 24.00 32.00TiO2 1.60 0.00Al2O3 1.60 2.10FeOT 8.20 11.00MgO 24.00 32.00CaO 13.50 17.90Na2O 2.50 3.10K2O 1.50 1.90H2O 7.10 0.00CO2 16.00 0.00Total 100.00 100.00Element Initial (kg/L) Final (kg/L) Initial (kg/L) Final (kg/L)Carbonate + Lherzolite Final (kg/L)Initial (kg/L) Final (kg/L)Lherzolite Final (kg/L)Si 8.70 0.99 6.46 5.88 2.53 10.60 1.34 1.39Al 0.35 0.06 0.26 0.22 0.19 1.06 0.33 0.30Fe 2.50 0.29 0.41 0.25 0.17 0.23 0.13 0.15Mg 13.10 0.70 5.45 4.48 2.44 0.43 0.58 0.67Ca 5.30 0.61 1.27 0.85 3.25 0.86 0.17 0.20Na 0.85 0.61 1.67 1.83 3.03 1.50 1.84 1.44K 0.35 0.00 0.88 0.94 0.79 0.00 0.00 0.00Total 31.15 3.25 16.39 14.45 12.40 14.68 4.40 4.15\"Carbonate\" indicates the addition of 30 moles of aragonite to the system. All models use a peridotite comprised of 75% olivine, 10% clinopyroxene, 10% garnet and 5% orthopyroxene unless otherwise noted. \"Lherzolite\" indicates the use of a peridotite comprised of 55% olivine, 30% clinopyroxene, 10% garnet and 5% orthopyroxeneTable 5.1. Initial & final elemental concentration of fluid phases used in DEW modelingKimberlitic Fluid (wt. %)Kimberlitic Fluid (molal) Asthenospheric Fluid (molal) Eclogitic Fluid (molal)51Changes in product mineral compositions are output by EQ6 as a function of the reaction progress variable, log zi, equal to the log moles of reactant rock titrated to the system. Reactants are instantaneously consumed with relative reaction rates of unity. Volatiles (CO2 and H2O) were added to the reaction separately to observe their respective and coupled effects on product mineral composition, in addition to magnetite (to substitute for the absence of ilmenite in the DEW database) and aragonite as a source of carbonate. 5.2 Kimberlitic Fluid Results A kimberlitic fluid reacting with “lherzolite” resulted in the crystallization of a typical megacryst assemblage comprised of olivine, garnet, and clinopyroxene, in addition to minor spinel and magnetite, the latter of which likely crystallized due to the inability of DEW to speciate TiO2. In a natural setting, we would expect ilmenite crystallization. No orthopyroxene was produced and increasing degrees of reaction yielded lower volumes of olivine than initially present in the reactant peridotite, suggesting the two were consumed to crystallize clinopyroxene and garnet (Table 5.2). Modeled olivine was compositionally comparable to Muskox megacrysts throughout the reaction, while modeled clinopyroxene and garnet reached identical compositions with Muskox megacrysts prior to the system equilibrating (Table 5.3; Fig. 5.1). The most diopside-rich clinopyroxene was produced in early stages of reaction (Fig. 5.1a), however the clinoenstatite endmember of clinopyroxene increased at the expense of diopside as the reaction progressed. The overabundance of the clinoenstatite component was observed to be a function of both orthopyroxene content in the reactant rock and the oxygen fugacity of the fluid. Therefore, we have only included results obtained with minimal orthopyroxene content under the most reduced conditions. Pyrope in garnet continually increased through the entirety of the reaction at the expense of grossular. Although 52 Fig. 5.1. Molal fraction of (a) diopside in clinopyroxene and (b) pyrope in garnet for product phases as a function of reaction progress (log zi) as calculated with the Deep Earth Water (DEW) model of Sverjensky et al. (2014). Fluid compositions used are kimberlitic (red line), asthenospheric (black line and green line) and eclogitic (blue line and pink line). Solid lines are reactions with “lherzolite”, dotted lines are reactions with “fertile lherzolite” and dashed lines indicate reactions with “fertile lherzolite” and additional carbonate. Shaded fields labeled “Muskox” represent the range of diopside and pyrope components calculated for Muskox megacrysts. 53Table 5.2. Modal abundance of product mineral phases from DEW modeling as a function of reaction progress (log zi)log zi Spinel Magnetite Olivine CPX Garnet-3.0000 2.1 0.8 74.6 22.6-2.5000 2.1 0.8 74.6 22.6-2.0000 2.1 0.8 74.5 22.7-1.5000 2.1 0.7 74.3 22.9-1.0000 2.3 0.6 73.7 23.5-0.5000 0.1 61.2 13.3 25.30.0000 53.0 16.1 31.00.5000 39.3 22.5 38.20.6232 35.7 24.4 39.8log zi Garnet CPX Hematite Olivine OPX Olivine Garnet Hematite CPX Calcite Meionite-3.0000 17.7 68.4 5.6 8.2 8.2 17.7 5.6 68.5-2.5000 18.1 68.1 5.5 8.3 8.2 18.0 5.5 68.2-2.0000 19.1 67.0 5.4 8.5 8.3 19.0 5.4 67.3-1.5000 21.9 64.1 5.1 8.9 4.6 21.7 5.2 66.8 1.7-1.0000 28.2 57.5 4.4 9.9 27.5 4.5 63.8 4.2-0.5000 37.6 48.1 3.3 11.0 34.9 3.5 56.4 5.30.0000 42.7 42.7 2.7 10.8 1.0 40.8 2.7 49.9 6.60.5000 39.8 2.3 47.2 8.8 1.91.0000 21.1 2.5 50.3 14.0 12.11.3979 2.5 62.9 22.1 12.6log zi Diamond CPX Garnet OPX Hematite Diamond CPX Garnet OPX Hematite Olivine-3.0000 0.8 99.2 0.8 99.2-2.5000 0.0 100.0 0.0 100.0-2.0000 100.0 100.0-1.5000 100.0 100.0-1.0000 100.0 100.0-0.5000 100.0 100.00.0000 62.4 37.6 62.4 37.60.5000 47.9 43.1 9.0 47.9 43.1 9.00.6232 47.9 43.1 9.0 47.9 43.1 9.01.0000 52.3 34.0 13.7 41.5 50.3 8.31.3871 52.3 34.0 13.7 33.9 47.1 17.2 1.6 0.11.4687 69.4 22.4 6.2 2.0Log zi is a measure of the log moles of the reactant rock consumed in the reaction. Blank cells indicate no crystallization. The final log zi value indicates the system has reached equilibrium. Meionite = Ca4Al6Si6O24CO3Kimberlitic FluidAsthenospheric Fluid Asthenospheric Fluid + Carbonate + Fertile LherzoliteEclogitic Fluid Eclogitic Fluid + Fertile Lherzolite54Table 5.3. Compositions of product mineral phases from DEW modeling as a function of reaction progress (log zi)log zi Pyrope Almandine Grossular Diopside Hedenbergite Clinoenstatite Jadeite Forsterite Fayalite-3.0000 - - - 91.2 3.0 5.8 0.0 92.2 7.8-2.5000 - - - 91.2 3.0 5.8 0.0 92.2 7.8-2.0000 - - - 91.1 3.0 5.8 0.0 92.2 7.8-1.5000 - - - 90.9 3.0 6.0 0.0 92.1 7.9-1.0000 - - - 90.3 3.2 6.5 0.0 91.8 8.2-0.5000 53.9 7.5 38.6 89.9 3.2 6.9 0.0 91.6 8.40.0000 64.8 9.1 26.0 85.2 3.1 11.7 0.1 91.5 8.50.5000 76.7 11.8 11.5 71.0 2.8 26.0 0.2 90.8 9.20.6232 78.2 12.7 9.0 65.8 2.8 31.2 0.3 90.3 9.7log zi Pyrope Almandine Grossular Diopside Hedenbergite Clinoenstatite Jadeite Forsterite Fayalite-0.5000 88.5 3.9 7.6 61.1 0.8 37.8 0.4 97.0 3.00.0000 88.5 3.9 7.5 60.9 0.8 37.9 0.4 97.0 3.00.5000 88.6 4.0 7.4 60.4 0.8 38.4 0.4 97.0 3.01.0000 88.9 4.1 7.0 58.8 0.8 40.0 0.4 96.9 3.11.1091 89.2 4.3 6.5 57.0 0.8 41.8 0.5 96.7 3.3log zi Pyrope Almandine Grossular Diopside Hedenbergite Clinoenstatite Jadeite Forsterite Fayalite-1.0000 88.3 3.9 7.9 61.9 0.8 36.9 0.4 - --0.5000 87.6 3.9 8.6 64.1 0.8 34.7 0.4 - -0.0000 85.8 3.8 10.4 68.6 0.9 30.1 0.4 - -0.5000 83.5 3.8 12.7 73.2 1.0 25.5 0.4 - -1.0000 82.3 3.6 14.1 75.3 1.0 23.4 0.4 - -1.3979 - - - 84.4 0.9 14.4 0.2 - -log zi Pyrope Almandine Grossular Diopside Hedenbergite Clinoenstatite Jadeite Forsterite Fayalite-2.5000 - - - 41.6 12.7 2.3 43.4 - --2.0000 - - - 42.4 12.5 2.4 42.6 - --1.5000 - - - 44.7 11.9 2.9 40.5 - --1.0000 - - - 48.8 10.5 4.7 36.0 - --0.5000 - - - 50.1 8.5 11.7 29.6 - -0.0000 65.0 28.8 6.2 48.1 6.2 26.7 19.0 - -0.5000 68.6 26.0 5.4 48.8 5.4 33.2 12.6 - -1.0000 68.3 25.8 5.8 53.5 5.9 33.2 7.4 - -1.4437 81.4 12.4 6.2 55.6 2.5 38.7 3.2 - -log zi Pyrope Almandine Grossular Diopside Hedenbergite Clinoenstatite Jadeite Forsterite Fayalite-2.0000 - - - 42.4 12.5 2.4 42.6 - --1.5000 - - - 44.7 11.9 2.9 40.5 - --1.0000 - - - 48.8 10.5 4.7 36.0 - --0.5000 - - - 50.1 8.5 11.7 29.6 - -0.0000 65.0 28.8 6.2 48.1 6.2 26.7 19.0 - -0.5000 68.6 26.0 5.4 48.8 5.4 33.2 12.6 - -1.0000 70.0 24.1 5.9 53.5 5.4 34.0 7.1 - -1.3871 81.9 11.9 6.3 56.4 2.4 39.0 2.3 90.8 9.2Pyrope = 100*(Mg/Mg+Ca+Fe), Almandine = 100*(Fe/Mg+Ca+Fe, Grossular = 100*(Ca/Mg+Ca+Fe), Diopside = 100*(Ca/Al+Mg+Fe), Hedenbergite = 100*(Fe/Al+Mg+Fe), Clinoenstatite = 100*(Mg-Ca/Al+Mg+Fe), Jadeite = 100*(Al/Al+Mg+Fe).Asthenospheric FluidGarnet Clinopyroxene OlivineEclogitic FluidGarnet Clinopyroxene OlivineEclogitic Fluid + LherzoliteGarnet Clinopyroxene OlivineKimberlitic FluidOlivineClinopyroxeneGarnetGarnet Clinopyroxene OlivineAsthenospheric Fluid + Carbonate + Lherzolite55both clinopyroxene and garnet had diopside and pyrope components comparable to those observed in megacrysts at a log zi of ~0 (Fig. 5.1), the modeled phases contained higher proportions of both clinoenstatite and grossular components than natural samples (Table 5.3). Changing the reactant rock to “fertile lherzolite” had minimal effect (≤1 mol.%) on either the composition of product phases or volume proportion of phases. Magnetite, carbonate and volatile addition changed end-member compositions less than 0.25 mol.%. 5.3 Asthenospheric Fluid Results An asthenospherically-derived fluid reacting with lherzolite failed to produce mineral compositions comparable to megacrysts (Fig. 5.1; Table 5.3), as phases were too magnesium-rich. The mineral assemblage produced in these reactions was dominated by clinopyroxene in low-degree reactions, while garnet increased to become volumetrically equal to clinopyroxene, in addition to lesser olivine, hematite and orthopyroxene (Table 5.2). Changing the reactant rock to “fertile lherzolite” with 30 moles of additional carbonate resulted in the crystallization of a significant volume of clinopyroxene that overlapped the composition of Muskox megacrysts at equilibrium, however the resulting garnet was significantly more pyrope-rich than megacrysts. Olivine was not produced, however this reaction crystallized significant quantities of both calcite and meionite (Ca4Al6Si6O24CO3), which were not observed in other reactions. The addition of magnetite, CO2 and H2O influenced mineral compositions on an order of less than 1 mol.%, regardless of the volume added. 565.4 Eclogitic Fluid Results An eclogitic fluid reacting with “lherzolite” yielded mineral compositions that strayed the furthest from megacryst compositions. Garnet produced by this fluid was compositionally comparable to megacrysts only in the initial stages of the ongoing reaction, however rapidly increased in pyrope as the reaction progresses (Fig. 5.1b; Table 5.3). Clinopyroxene produced in this reaction initially contained a significant jadeite component that quickly decreased, while diopside and clinoenstatite increased, but did not reach megacrystic compositions (Fig. 5.1a). Clinopyroxene crystallized through the entire reaction and comprised nearly the entire product assemblage in low degrees of reaction, while garnet only crystallized as the system reached equilibrium (Table 5.2). A significant amount of orthopyroxene was produced, a feature unique to reactions with eclogitic fluids. Changing the rock to a “fertile lherzolite” had only a minor influence on mineral compositions, yet affected modes of product minerals significantly, most notably increasing both garnet and orthopyroxene contents (Tables 5.2 and 5.3). Minor quantities of hematite were produced in both reactions, as well as diamond in the lowest degrees of reaction. Neither magnetite nor aragonite addition affected product phases significantly (≤1 mol.%). 57Chapter 6 Discussion 6.1 Equilibrium Melt Modeling Equilibrium melts for clinopyroxene megacrysts were calculated using experimental partition coefficients for silico-carbonate (Girnis et al. 2013) and carbonatitic (Dasgupta et al. 2009) melts. Equilibrium melt patterns of clinopyroxene megacrysts calculated using D values for alkali basalts from Hart and Dunn (1993) have previously exhibited strong resemblance to those of proto-kimberlitic melts (Burgess and Hart 2004; Kargin et al. 2017). Despite these apparent similarities, this set of D values for purely silicate melts are inappropriate for this modeling application (Moore and Belousova 2005). It is widely acknowledged that kimberlitic and proto-kimberlitic melts are at least partially carbonate-bearing (e.g. Brey et al. 2008; Russell et al. 2012; Girnis et al. 2013) and the appropriate partition coefficients should account for the presence of carbonate. Equilibrium melts computed based on D values for silico-carbonate melts differ substantially from the trace element signature of the Muskox kimberlite (Fig. 6.1). LREE concentrations of the calculated melt differ up to four orders of magnitude, whereas HREE concentrations show a discrepancy of less than one order of magnitude. The HFSE concentrations in calculated melts differ substantially from Muskox, demonstrating the strongest mismatch between the extreme (>6000-9000 times chondrite) enrichment in Hf and Zr in calculated equilibrium melts and the negative anomalies for the Muskox kimberlite. Depletion of Zr and Hf relative to Sm and Nd, according to Girnis et al. (2013), is the most reliable indicator of carbonate-rich melt metasomatism. 58 Fig. 6.1 Equilibrium melt concentrations (blue lines) calculated using D values of Girnis et al. (2013) for silico-carbonate melts. Calculated melts are compared with both the Muskox kimberlite (red line) and Jericho megacrysts (blue field; Kopylova et al. 2009). Fig. 6.2 Equilibrium melt concentrations (green lines) calculated using D values for carbonatitic melts from Dasgupta et al. (2009) and compared with data for both the Muskox kimberlite (red line) as well as global carbonatites (red field) from Ionov and Harmer (2002), Bizimus et al. (2003) and Chandra et al. (2018). 59 Equilibrium melts computed based on D values for carbonatitic melts (Fig. 6.2) show significantly lower overall concentrations of trace elements compared to silico-carbonate melts. Calculated concentrations have been compared with trace element data from various carbonatite occurrences globally (Ionov and Harmer 2002; Bizimus et al. 2003; Chandra et al. 2018). Both the trend and overall concentrations between the two are nearly identical, with the largest discrepancy observed in the HFSE which are more enriched in the calculated melt (>110-150 times chondrite) relative to reported carbonatite concentrations, which correspond to chondritic values. Both LREE and HREE calculated for calculated melts plot either near or within the range of reported values for global carbonatites. Results from equilibrium melt calculations suggest that the melt parental to Muskox megacrysts may have been carbonatitic rather than silico-carbonate in composition. 6.2 Isotope Systematics Studied samples comprise two distinct groups with respect to Sr-Nd-Pb isotope systematics. The majority of megacrysts, websterites, metasomatic clinopyroxene in Muskox peridotite and Muskox and Jericho kimberlites plot as a group close to BSE, while primary clinopyroxene in peridotite MOX-3-33.0 deviates significantly with atypically low 143Nd/144Nd and 206Pb/204Pb and may represent a pocket of ancient lithospheric mantle (Figs. 4.6, 4.7, 4.8, 4.9). The origin of primary clinopyroxene as a relic of enriched ancient subcontinental lithospheric mantle (SCLM) can be explained by its highly unradiogenic isotopic signature in conjunction with LREE enrichment and extremely fractionated middle- and heavy-REE (Fig. 4.2). An age for this lithospheric enrichment can be approximated by taking the present-day Sr and Nd ratios of BSE and CHUR (0.70445 and 0.512638 respectively) and back-calculating to an age that matches the measured ratios of MOX-3-33.0 (Table 4.4). Doing so provides two age estimates, 605 Ma for Sr 60and 1.09 Ga for Nd (Fig. 4.9a), that bracket the minimum and maximum ages of this SCLM enrichment. These constraints correlate well with the Pb-Pb systematics of this sample, which plot to the right of the 1 Ga geochron (Fig. 4.7), however all three are purely model ages and have no statistical significance. The Muskox kimberlite possesses a less radiogenic Nd signature than South African kimberlites (Fig. 4.9), and lower Nd ratios are observed in all sample types from Muskox (Figs. 4.8, 4.9), but not at the adjacent Jericho. The relic pocket of the enriched SCLM must have been tapped very locally by the Muskox kimberlite, but not sampled by Jericho melts 15 km to the NE. Such isotopic heterogeneity is expected from the Slave mantle, which is known to be stratigraphically complex, with differential enrichment and model ages in various spatial and depth domains, as well as with significant depth-dependent metasomatic refertilization (Kopylova and Russell 2000; Heaman and Pearson 2010). The Sr-Nd-Pb isotope systematics for studied samples reveal that all megacrysts, websterites, metasomatic clinopyroxene in peridotite and Muskox and Jericho kimberlites plot intermediate between the EM1 and HIMU mantle endmembers, suggesting mixing between the two. The enriched Nd signature seen in all Muskox samples (Figs. 4.8, 4.9) requires the addition of a third reservoir of locally restricted ancient SCLM beneath Muskox, represented by primary peridotitic clinopyroxene. While the cratonic mantle has been known to possess isotopic enrichment comparable to EM1 (e.g. Menzies 1989; Zhang et al. 2003; Tang et al. 2007), the HIMU reservoir may represent a metasomatizing carbonatitic fluid that acquired its signature through Archean subduction (Weiss et al. 2016) in addition to its traditional association with recycled oceanic crustal material contaminating OIBs (e.g. Zindler and Hart 1986; Weaver 1991; Hofmann 1997). Alternative models also ascribe the HIMU signature of carbonatites to a derivation of plumes from 61the core-mantle boundary and the associated graveyard of subducted slabs (Bell and Tilton 2001), or as melts generated in the periphery of an upwelling plume head that penetrated a weakened slab (Mc-Coy West et al. 2016). To model metasomatism of EM1 mantle peridotite by a HIMU carbonatitic fluid, we investigated the effects of volumetrically small (1-5 %) additions of the fluid in an isotopic mixing model (Table 6.1). Model mixing lines (dashed black lines on Figs. 4.7, 4.8, 4.9) were calculated from elemental concentrations for whole-rock cratonic peridotite (Schmidberger et al. 2001) and carbonatite (Ionov and Harmer 2002) with mantle reservoir values from Hart et al. (1992). Isotopic vs. elemental concentrations for these mixing models can be found in Appendix F. All megacryst, websterite and kimberlite samples in all isotopic coordinates plot within the EM1-HIMU-primary clinopyroxene triangle and can be resolved as a combination of these mantle reservoirs. The 206Pb/204Pb and 207Pb/204Pb measured in all samples plot nearly on top of the mixing line between EM1 and HIMU mantle with minimal deviation (Fig. 4.7). EM1 mantle need only react with very low proportions of fluid (< 1%) to reconcile the isotopic ratios observed in Muskox and Jericho samples. Samples span a similar range of values as PIC and MARID clinopyroxene (Fitzpayne et al. 2019) and are almost entirely restricted to the overlapping fields of East African carbonatites (Kalt et al. 1997; Bell and Tilton 2001) and cratonic peridotite (Schmidberger et al. 2001; Wittig et al. 2007; Liu et al. 2012). Therefore the 206Pb/204Pb and 207Pb/204Pb systematics of Muskox samples are interpreted as a result of reservoir mixing rather than reflecting distinct secondary Pb-Pb isochron ages (Appendix E). On the basis of Sr-Nd-Pb isotope systematics, it would appear that a strict genetic link between a single megacryst suite and its host kimberlite does not exist. Muskox megacrysts contain more radiogenic Pb and Nd than the host kimberlite, and the Muskox proto-kimberlitic melt was unlikely 62Table 6.1. Parameters for isotope mixing modelsEM1 Peridotite HIMU Carbonatite Ancient SCLM§87Sr/86Sr 0.70530* 0.70285* 0.70368Sr (ppm) 37.5† 996‡ 1109143Nd/144Nd 0.51236* 0.51285* 0.51123Nd (ppm) 1.76† 244‡ 44.3206Pb/204Pb 17.4* 21.8* 16.1207Pb/204Pb 15.5* 15.9* 15.3Pb (ppm) 0.42† 22.3‡ 5.87§This study (MOX-3-33.0)‡Ionov and Harmer (2002)†Schmidberger et al. (2001)*Hart et al. (1992)Concentrations used for our HIMU carbonatitic fluid are taken from data for minimally contaminated whole-rock carbonatite reported by Ionov and Harmer (2002). Concentrations used for our HIMU carbonatitic fluid are taken from data for minimally contaminated whole-rock carbonatite reported by Ionov and Harmer (2002)63the agent that metasomatized local peridotitic mantle to crystallize megacrysts. Moreover, Muskox megacrysts plot on a single unifying 206Pb/204Pb-208Pb/204Pb trend together with Jericho kimberlite and other Muskox mantle samples, yet Muskox kimberlite deviates from this trend (inset Fig. 4.7) due to its outlying Th/U. Similar deviation exists in the εNd between Muskox kimberlite (-0.04) and the similar (predominantly within 1 epsilon unit) values of websterite, megacrysts and Jericho kimberlite. Our results imply that megacryst, websterite and metasomatic clinopyroxene crystallize from a carbonatitic fluid that regionally metasomatized enriched lithospheric mantle and may have evolved into distinct, yet temporally and spatially related batches of Muskox and Jericho kimberlite melt. The absence of a strictly cognate relationship of Cr-rich megacrysts and their host kimberlite was also shown for Lac de Gras megacrysts on the basis of polymineralic inclusions, trace element systematics and Sr isotope signatures (Bussweiler et al. 2018). 6.3 DEW Modeling Among three tested fluid compositions, kimberlitic, asthenospheric and eclogitic, kimberlitic fluid produced results that were closer in compositions to Muskox megacrysts, yet even this fluid yielded significant compositional disparities between natural megacrysts and the modeled reaction products. Compositions of clinopyroxene and garnet produced in reaction with kimberlitic fluid were closest to megacrysts at a log zi of 0 but continued to evolve to lower diopside and higher pyrope components, suggesting that megacrystic compositions would be reached while kimberlitic fluids are still in moderate disequilibrium with peridotitic mantle (Fig. 5.1; Table 5.3). The most notable mismatch between the modeled and empirical megacryst mineralogy is the presence of an unrealistically large clinoenstatite component in product 64clinopyroxene (5.8-31.2 mol.% in kimberlitic fluid models). This discrepancy with Muskox megacrysts may be due to a number of modeling constraints. First, the availability of calculated equilibrium constants within the DEW database only extend to pressures and temperatures (6 GPa and 1000 °C) lower than the observed conditions of megacryst crystallization (i.e. 7 GPa, 1100-1250 °C at Jericho; Kopylova et al. 2009). Second, the composition of the low-T, primitive kimberlitic fluid used may not be representative of proto-kimberlitic fluids, as the composition used in modeling was based on the lowest pressure and temperature experiments of Stamm and Schmidt (2017) in an attempt to coincide with the limitations of the DEW database. Finally, the mismatch may emphasize the predominantly carbonatitic nature of the metasomatizing agent responsible for megacryst crystallization. The misfit between megacrysts and modeled reaction products suggests that DEW was not entirely appropriate for modeling the proto-kimberlite or carbonatitic metasomatism, as DEW is designed for purely hydrous fluids (Sverjensky 2019). 65Chapter 7 Conclusions 7.1 Concluding Remarks Megacrysts from Muskox bear similarities to previously reported megacrysts from worldwide kimberlite occurrences: the presence of both the high-Cr and low-Cr suites with a lack of samples intermediate between the two (Eggler et al. 1979), a tight clustering of Mg-numbers within suites (Kargin et al. 2017; Bussweiler et al. 2018) and compositional overlap between high-Cr megacrysts and equivalent phases in websterite (Kopylova et al. 2009). Megacryst suites from both the Muskox and Jericho kimberlites similarly transition to websterites and are isotopically and compositionally analogous, suggesting a common origin for the two. Muskox megacrysts can be portrayed as ordinary samples from a broad swath of the metasomatized, carbonated HIMU-affected mantle that comprises many mantle materials, including individual clinopyroxene grains in peridotites, the entire websterite lithology and kimberlites. The isotopic similarity of clinopyroxene in mantle peridotite to both megacrysts and websterites suggest the distal metasomatic infiltration of the isotopically distinct HIMU-rich component, rather than a distinct megacryst magma body (e.g. Burgess and Harte, 2004; Doyle et al. 2004). Ambiguous relationships may link these rock types in the metasomatized mantle domain. One view may suggest carbonatitic HIMU fluids percolated through the older lithospheric mantle reworking it to differing degrees, with kimberlite possibly representing a final product (Fig. 7.1a). In this framework, the observed geochemical similarities between suites (high-Cr megacrysts and websterites; low-Cr megacrysts and kimberlites) suggest a metasomatic column that evolves progressively with the addition of more carbonatitic fluid. The evolution from high-Cr to low-Cr assemblages due to the increased fluid/rock ratios transforms: 1) EM1 or enriched SCLM (peridotite MOX-3-33.0) to 2) metasomatic peridotitic clinopyroxene to 3) websterite and high-Cr 66 Fig. 7.1 The proposed formation model for Muskox megacrysts, wherein subduction related HIMU (carbonatitic) fluids progressively metasomatize EM1 lithosphere to form megacrysts, websterite and metasomatic clinopyroxene. Kimberlite magmas are generated in one of two ways: (a) through the continuous reaction with SCLM, driving the fluid from a carbonatitic to kimberlitic composition that later entrains megacrysts. (b) Alternatively, kimberlite melts may be generated through the melting of previously HIMU metasomatized SCLM. Locally restrictedancient SCLMCarbonatitic fluidsLow-Cr megacrystsWebsterite & high-Cr megacrystsMetasomatized SCLMEM1 mantle/enrichedSCLMProgressivemetasomatisma.) Evolution of fluid from carbonatitic to kimberlitic compositionthrough reactionwith SCLMEM1 mantleb.) Generation of kimberlitic fluid through melting of previouslymetasomatized SCLMSubduction-relatedHIMU fluidsSubducting slabLithosphereAsthenosphere67megacrysts to 4) low-Cr megacryst and kimberlites. This model portrays carbonatitic HIMU fluids as proto-kimberlitic, in line with multiple previous workers (Moore and Belousova, 2005; Kopylova et al. 2009; Kargin et al. 2017; Bussweiler et al. 2018). An alternative view to connect HIMU-affected mantle materials below Muskox would be through the generation of kimberlite melt in the HIMU-metasomatized mantle (Fig. 7.1b). In this model, kimberlite melts are secondary to the more spatially extensive process of carbonate metasomatism and are not directly related to megacrysts. In this case, the precursory carbonate metasomatism could not have significantly predated the 173 Ma kimberlite extraction, otherwise we would observe the enriched radiogenic signature of the long-evolved SCLM. Of these two models proposed, both would appear equally valid, but neither is favored by the authors. In both models, the temporal evolution proceeds from carbonatitic to more silicate-carbonate compositions of fluids/melts, giving new independent confirmation to the evolution of proto-kimberlite and primary kimberlite melts (Russell et al. 2012; Gervasoni et al. 2017). Our data presented in the framework of a metasomatic origin of megacrysts provide three independent arguments for an initial carbonatitic nature of the agent that may evolve into subsequent silicate-carbonate (kimberlitic) melt. The first is the stronger trace element match between parent megacryst melt and carbonatites (Fig. 6.2). The second is the broad involvement of the HIMU carbonatitic source (Figs. 4.7, 4.8, 4.9). And finally, we argue that the inability of the purely hydrous DEW model to reproduce megacrysts in reactions with the ambient mantle may be a confirmation of the carbonate-rich nature of megacryst metasomatism. 687.2 Future Work The megacryst formation model has seen a dramatic evolution in the last two decades from theories first invoking fractionating magmas towards those citing metasomatism as the primary driver of megacryst crystallization. Despite this shift in thinking, a number of questions remain that offer much opportunity for future studies. First, there exists a clear gap in reported Pb isotope data for kimberlitic megacrysts in the literature. At the time of writing, Davies et al. (2001) provides the only dataset for Pb isotopes for African megacrysts, and we provide the first dataset for Slave megacrysts. As highlighted in this work, the Pb isotope system is a powerful fingerprinting tool that can supplement more frequently used systems like Sr-Nd-Hf, and it would be beneficial to extend the Pb isotope dataset for kimberlitic megacrysts to more heavily studied kimberlite provinces (e.g. Lac de Gras). Doing so would not only allow for additional isotopic comparisons between megacrysts, kimberlites and additional metasomatized mantle lithologies from a single locality, but also with megacrysts globally. Second, our study highlights the application of isotopic mixing models rather than isochrons to interpret the isotopic systematics of megacrysts. In doing so, we reveled the integral role of a HIMU mantle component in the isotopic systematics of megacrysts, interpreted to be the signature of a carbonatitic fluid. Isotopic mixing models have not been utilized in previous studies, leaving us with the question of whether this isotopic mixing is unique to the Muskox mantle, or whether we are simply the first to apply them to megacrysts. In a similar regard, we report the same compositional (and now isotopic) similarities between websteritic and megacrystic clinopyroxene that was reported at the Jericho kimberlite. This similarity has yet to be uncovered 69elsewhere, making it, again, unclear whether Muskox and Jericho are unique in this regard, or whether these similarities have simply been overlooked at other kimberlite occurrences. 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Annual Review of Earth and Planetary Sciences, 14, 517. 84Appendix A: Photographs of Megacrysts 8510mmMOX-24-124.0A10mmMOX-24-34.310mmMOX-24-43.35Clinopyroxene10mmMOX-24-209.710mm 10mmMOX-28-320.1 86MOX-25-161.5c10mmMUSK-3-151.810mmMUSK-3-198.3710mmMUSK-3-202.4Clinopyroxene8710mmMOX-3-74.410mmMOX-24-206.910mmMOX-24-209.710mmMOX-24-209.710mmMOX-25-65.1610mmMOX-24-206.7Ilmenite8810mmMOX-28-308Ilmenite8910mmMOX-25-124.8Garnet9010mmMOX-24-102.810mmMOX-25-161.5G-2Olivine91Polymineralic MegacrystsMOX-24-240.2 MOX-24-42.6Field of View: 50 mm92Polymineralic MegacrystsMOX-24-230.7Field of View: 50 mm93Clinopyroxene Garnet Olivine IlmeniteSiO2, wt.% 0.03 0.03 0.03 0.03TiO2, wt..% 0.03 0.03 0.03 0.04Al2O3,wt.% 0.02 0.04 0.03 0.05Cr2O3, wt.% 0.05 0.05 0.05 0.06FeOT, wt.% 0.05 0.06 0.06 0.07MnO, wt.% 0.05 0.05 0.05 0.06MgO, wt.% 0.03 0.03 0.03 0.03CaO, wt.% 0.03 0.03 0.02 0.03Na2O, wt.% 0.07 0.05K2O, wt.% 0.02NiO, wt.% 0.07Nb2O5, wt.% 0.10Appendix B. Major Element Analyses of Megacrysts Calculated minimum detection limits (MDL) for microprobe analyses. Blank cells indicate elements that werenot measured 94Sample Mineral Suite Point Area SiO2, wt.% TiO2, wt.% Al2O3,wt.% Cr2O3, wt.% FeOT, wt.% MnO, wt.% MgO, wt.% CaO, wt.% Na2O, wt.% NiO, wt.% TotalMUSK-3-202.4 Clinopyroxene High-Cr 1 Core 55.93 0.25 1.94 1.10 3.36 0.12 17.46 19.64 1.71 101.50MUSK-3-202.4 Clinopyroxene High-Cr 2 Core 55.01 0.27 1.77 1.08 3.53 0.13 17.41 19.61 1.73 100.54MUSK-3-202.4 Clinopyroxene High-Cr 3 Core 54.99 0.24 1.76 0.99 3.61 0.09 17.40 19.49 1.72 100.29MUSK-3-202.4 Clinopyroxene High-Cr 4 Core 54.58 0.23 1.82 0.98 3.35 0.10 17.34 19.80 1.56 99.77MUSK-3-202.4 Clinopyroxene High-Cr 5 Core 54.49 0.25 1.77 1.07 3.42 0.11 17.30 19.92 1.68 100.01MUSK-3-202.4 Clinopyroxene High-Cr 6 Core 54.12 0.26 1.79 1.04 3.39 0.15 17.19 19.96 1.63 99.51MUSK-3-202.4 Clinopyroxene High-Cr 7 Core 55.06 0.24 1.82 1.09 3.49 0.09 17.58 19.73 1.65 100.74MUSK-3-202.4 Clinopyroxene High-Cr 8 Rim 55.23 0.23 1.84 1.01 3.43 0.10 17.50 19.87 1.64 100.85MUSK-3-202.4 Clinopyroxene High-Cr 9 Rim 54.73 0.27 1.90 1.16 3.54 0.09 17.22 19.70 1.87 100.49MUSK-3-202.4 Clinopyroxene High-Cr 10 Rim 55.01 0.21 1.83 1.07 3.51 0.16 17.14 19.94 1.71 100.59MUSK-3-202.4 Clinopyroxene High-Cr 11 Rim 55.07 0.26 1.81 1.07 3.31 0.10 17.50 19.73 1.57 100.43MUSK-3-202.4 Clinopyroxene High-Cr 12 Rim 54.48 0.23 1.80 1.09 3.56 0.13 17.17 19.87 1.67 100.00MUSK-3-202.4 Clinopyroxene High-Cr 13 Rim 54.51 0.23 1.74 0.96 3.46 0.07 17.27 19.81 1.72 99.78MUSK-3-202.4 Clinopyroxene High-Cr 14 Rim 53.52 0.25 1.83 1.14 3.47 0.11 17.52 20.07 1.67 99.57MUSK-3-202.4 Clinopyroxene High-Cr 15 Rim 54.77 0.25 1.84 1.09 3.54 0.11 17.59 19.77 1.67 100.63MUSK-3-202.4 Clinopyroxene High-Cr 16 Rim 55.28 0.24 1.84 1.04 3.60 0.12 17.24 19.89 1.63 100.87MOX-24-124A Clinopyroxene High-Cr 1 Core 53.60 0.23 1.93 1.35 3.11 0.10 17.03 19.88 1.69 98.92MOX-24-124A Clinopyroxene High-Cr 2 Core 54.50 0.25 1.88 1.48 3.29 0.11 17.31 19.84 1.79 100.45MOX-24-124A Clinopyroxene High-Cr 3 Core 55.01 0.26 1.99 1.27 3.32 0.16 17.16 19.63 1.87 100.66MOX-24-124A Clinopyroxene High-Cr 4 Core 54.62 0.29 2.03 1.48 3.31 0.13 17.28 19.10 2.03 0.10 100.36MOX-24-124A Clinopyroxene High-Cr 5 Core 55.25 0.28 2.05 1.31 3.43 0.13 17.10 19.38 1.90 100.84MOX-24-124A Clinopyroxene High-Cr 6 Core 54.64 0.27 2.04 1.20 3.41 0.12 17.27 19.46 1.78 100.18MOX-24-124A Clinopyroxene High-Cr 7 Core 54.81 0.25 2.03 1.06 3.37 0.10 17.34 19.48 1.90 100.34MOX-24-124A Clinopyroxene High-Cr 8 Core 54.88 0.27 2.06 1.25 3.36 0.14 17.19 19.27 1.87 100.29MOX-24-124A Clinopyroxene High-Cr 9 Core 54.92 0.27 2.01 1.06 3.44 0.15 17.27 19.38 1.87 100.39MOX-24-124A Clinopyroxene High-Cr 10 Core 54.71 0.27 1.96 1.13 3.35 0.09 17.45 19.31 1.91 100.18MOX-24-124A Clinopyroxene High-Cr 11 Rim 54.76 0.24 1.90 1.33 3.24 0.13 17.18 19.78 1.76 100.32MOX-24-124A Clinopyroxene High-Cr 12 Rim 54.70 0.28 1.92 1.32 3.21 0.07 17.17 19.70 1.82 100.19MOX-24-124A Clinopyroxene High-Cr 13 Rim 54.23 0.26 1.89 1.34 3.37 0.09 17.18 19.93 1.80 100.09MOX-24-124A Clinopyroxene High-Cr 14 Rim 54.01 0.25 1.85 1.24 3.32 17.10 19.93 1.65 99.35MOX-24-124A Clinopyroxene High-Cr 15 Rim 55.03 0.27 1.87 1.28 3.24 0.09 17.24 19.94 1.85 100.80MOX-24-124A Clinopyroxene High-Cr 16 Rim 54.33 0.22 1.92 1.22 3.19 0.14 17.26 19.99 1.80 100.07MOX-24-124A Clinopyroxene High-Cr 17 Rim 54.59 0.23 1.89 1.38 3.23 0.11 17.10 19.94 1.85 100.33MOX-24-124A Clinopyroxene High-Cr 18 Rim 54.72 0.26 2.02 1.26 3.47 0.10 17.23 19.37 1.86 100.29MOX-24-124A Clinopyroxene High-Cr 19 Rim 55.16 0.25 1.95 1.28 3.34 0.12 17.16 19.65 1.90 100.81MOX-24-124A Clinopyroxene High-Cr 20 Rim 54.82 0.25 1.82 1.31 3.33 0.07 17.13 19.87 1.83 100.43MOX-24-124A Clinopyroxene High-Cr 21 Rim 54.53 0.27 1.81 1.34 3.27 0.11 17.07 19.91 1.82 100.14MOX-24-124A Clinopyroxene High-Cr 22 Rim 54.86 0.28 1.84 1.24 3.39 0.09 17.23 19.94 1.83 100.71MOX-24-124A Clinopyroxene High-Cr 23 Rim 54.96 0.27 1.90 1.31 3.32 0.13 17.16 20.02 1.80 100.86MOX-24-124A Clinopyroxene High-Cr 24 Rim 55.24 0.29 1.85 1.31 3.28 0.12 17.36 19.99 1.78 101.22MUSK-3-158.8 Clinopyroxene High-Cr 1 Rim 54.84 0.27 1.94 0.76 3.36 0.09 17.26 20.69 1.67 100.88MUSK-3-158.8 Clinopyroxene High-Cr 2 Rim 54.34 0.25 1.97 0.68 3.33 0.12 17.05 20.96 1.58 100.29MUSK-3-158.8 Clinopyroxene High-Cr 3 Rim 54.79 0.26 2.01 0.75 3.28 0.07 17.32 20.96 1.59 101.03MUSK-3-158.8 Clinopyroxene High-Cr 4 Rim 54.06 0.25 1.99 0.73 3.30 0.16 17.30 20.99 1.55 100.32MUSK-3-158.8 Clinopyroxene High-Cr 5 Rim 54.10 0.18 1.94 0.85 3.22 0.10 17.04 20.89 1.71 100.02MUSK-3-158.8 Clinopyroxene High-Cr 6 Core 54.90 0.29 1.96 0.80 3.26 0.12 17.00 20.69 1.70 100.74MUSK-3-158.8 Clinopyroxene High-Cr 7 Core 53.71 0.20 1.90 0.79 3.28 0.09 16.68 20.60 1.57 98.82MUSK-3-158.8 Clinopyroxene High-Cr 8 Core 54.47 0.25 1.94 0.74 3.23 0.13 16.90 20.79 1.67 100.12MUSK-3-158.8 Clinopyroxene High-Cr 9 Core 54.71 0.20 1.96 0.76 3.25 0.08 16.78 20.62 1.62 99.98MUSK-3-158.8 Clinopyroxene High-Cr 10 Core 54.15 0.27 1.91 0.78 3.31 0.10 16.81 20.80 1.65 99.78MUSK-3-198.37 Clinopyroxene High-Cr 1 Rim 54.40 0.25 2.01 1.00 3.41 0.11 17.00 20.10 1.69 99.97MUSK-3-198.37 Clinopyroxene High-Cr 2 Rim 53.72 0.23 1.95 0.89 3.33 0.11 17.00 19.90 1.87 99.00MUSK-3-198.37 Clinopyroxene High-Cr 3 Rim 54.15 0.27 1.93 1.02 3.35 0.07 17.01 20.07 1.67 99.53MUSK-3-198.37 Clinopyroxene High-Cr 4 Rim 53.93 0.27 1.96 1.04 3.28 0.12 17.05 19.95 1.75 99.36MUSK-3-198.37 Clinopyroxene High-Cr 5 Rim 54.17 0.22 1.94 0.99 3.33 0.11 16.99 19.89 1.87 99.50MUSK-3-198.37 Clinopyroxene High-Cr 6 Core 54.14 0.23 1.88 1.05 3.38 0.12 17.01 20.24 1.64 99.69MUSK-3-198.37 Clinopyroxene High-Cr 7 Core 54.35 0.23 2.01 1.05 3.33 0.08 17.00 20.07 1.86 99.99MUSK-3-198.37 Clinopyroxene High-Cr 8 Core 54.05 0.25 1.98 1.06 3.36 0.12 17.12 20.12 1.56 99.62MUSK-3-198.37 Clinopyroxene High-Cr 9 Core 53.96 0.26 1.90 0.95 3.40 0.08 17.17 20.07 1.77 99.55MUSK-3-198.37 Clinopyroxene High-Cr 10 Core 53.89 0.24 1.98 0.97 3.36 0.13 16.97 20.01 1.71 99.26Appendix B: Major Element Analyses of MegacrystsEmpty cells indicate concentrations that were below minimum detection levels95Sample Mineral Suite Point Area SiO2, wt.% TiO2, wt.% Al2O3,wt.% Cr2O3, wt.% FeOT, wt.% MnO, wt.% MgO, wt.% CaO, wt.% Na2O, wt.% NiO, wt.% TotalMUSK-3-198.37 Clinopyroxene High-Cr 1 Rim 54.40 0.25 2.01 1.00 3.41 0.11 17.00 20.10 1.69 99.97MUSK-3-198.37 Clinopyroxene High-Cr 2 Rim 53.72 0.23 1.95 0.89 3.33 0.11 17.00 19.90 1.87 99.00MUSK-3-198.37 Clinopyroxene High-Cr 3 Rim 54.15 0.27 1.93 1.02 3.35 0.07 17.01 20.07 1.67 99.53MUSK-3-198.37 Clinopyroxene High-Cr 4 Rim 53.93 0.27 1.96 1.04 3.28 0.12 17.05 19.95 1.75 99.36MUSK-3-198.37 Clinopyroxene High-Cr 5 Rim 54.17 0.22 1.94 0.99 3.33 0.11 16.99 19.89 1.87 99.50MUSK-3-198.37 Clinopyroxene High-Cr 6 Core 54.14 0.23 1.88 1.05 3.38 0.12 17.01 20.24 1.64 99.69MUSK-3-198.37 Clinopyroxene High-Cr 7 Core 54.35 0.23 2.01 1.05 3.33 0.08 17.00 20.07 1.86 99.99MUSK-3-198.37 Clinopyroxene High-Cr 8 Core 54.05 0.25 1.98 1.06 3.36 0.12 17.12 20.12 1.56 99.62MUSK-3-198.37 Clinopyroxene High-Cr 9 Core 53.96 0.26 1.90 0.95 3.40 0.08 17.17 20.07 1.77 99.55MUSK-3-198.37 Clinopyroxene High-Cr 10 Core 53.89 0.24 1.98 0.97 3.36 0.13 16.97 20.01 1.71 99.26MOX-24-34.3 Clinopyroxene High-Cr 1 Rim 53.60 0.25 1.87 1.24 3.28 0.11 17.39 19.79 1.90 99.42MOX-24-34.3 Clinopyroxene High-Cr 2 Rim 54.25 0.22 1.89 1.28 3.22 0.13 17.39 19.66 1.74 99.79MOX-24-34.3 Clinopyroxene High-Cr 3 Rim 54.37 0.25 1.94 1.25 3.22 0.13 17.16 19.64 1.71 99.66MOX-24-34.3 Clinopyroxene High-Cr 4 Rim 53.68 0.24 1.93 1.32 3.21 0.10 17.63 19.75 1.73 99.60MOX-24-34.3 Clinopyroxene High-Cr 5 Rim 54.61 0.23 1.80 1.24 3.03 0.08 17.49 19.83 1.67 99.97MOX-24-34.3 Clinopyroxene High-Cr 6 Core 54.13 0.26 1.85 1.25 3.13 0.15 17.17 19.97 1.86 99.78MOX-24-34.3 Clinopyroxene High-Cr 7 Core 55.18 0.24 1.95 1.34 3.34 0.11 17.19 19.74 1.88 100.96MOX-24-34.3 Clinopyroxene High-Cr 8 Core 54.36 0.22 1.83 1.27 3.21 0.12 16.98 19.90 1.66 99.55MOX-24-34.3 Clinopyroxene High-Cr 9 Core 54.40 0.21 1.85 1.35 3.29 0.06 17.21 19.76 1.86 99.99MOX-24-34.3 Clinopyroxene High-Cr 10 Core 53.80 0.21 1.87 1.27 3.10 0.10 17.07 19.64 1.68 98.75MOX-28-320.1 Clinopyroxene High-Cr 1 Rim 54.75 0.23 1.90 0.93 3.41 0.10 16.98 20.53 1.66 100.50MOX-28-320.1 Clinopyroxene High-Cr 2 Rim 54.93 0.28 1.96 0.84 3.28 0.08 17.16 20.22 1.75 100.51MOX-28-320.1 Clinopyroxene High-Cr 3 Rim 54.98 0.24 1.97 0.95 3.26 0.12 17.18 20.43 1.74 100.87MOX-28-320.1 Clinopyroxene High-Cr 4 Rim 55.20 0.20 1.81 0.91 3.41 0.10 17.42 20.70 1.63 0.09 101.45MOX-28-320.1 Clinopyroxene High-Cr 5 Rim 54.23 0.26 1.84 0.99 3.21 0.11 17.47 20.48 1.49 100.08MOX-28-320.1 Clinopyroxene High-Cr 6 Core 54.71 0.25 1.94 1.08 3.41 0.12 17.28 20.34 1.63 100.76MOX-28-320.1 Clinopyroxene High-Cr 7 Core 54.47 0.25 1.91 0.99 3.52 0.09 17.07 20.34 1.62 100.26MOX-28-320.1 Clinopyroxene High-Cr 8 Core 54.89 0.24 1.87 0.95 3.31 0.13 17.24 20.54 1.73 100.90MOX-28-320.1 Clinopyroxene High-Cr 9 Core 54.70 0.25 1.83 0.91 3.34 0.09 17.10 20.39 1.65 100.26MOX-28-320.1 Clinopyroxene High-Cr 10 Core 55.01 0.26 1.89 1.00 3.22 16.82 20.26 1.68 100.13MOX-25-161.5C Clinopyroxene High-Cr 1 Core 54.48 0.30 2.04 1.20 3.49 0.12 17.05 19.06 1.85 99.58MOX-25-161.5C Clinopyroxene High-Cr 2 Core 53.99 0.29 2.02 1.46 3.35 0.10 17.00 19.15 1.86 99.21MOX-25-161.5C Clinopyroxene High-Cr 3 Core 54.74 0.35 2.14 1.34 3.33 0.13 17.28 18.86 1.91 100.07MOX-25-161.5C Clinopyroxene High-Cr 4 Core 54.23 0.30 2.06 1.13 3.54 0.14 17.48 19.38 1.88 100.13MOX-25-161.5C Clinopyroxene High-Cr 5 Core 54.05 0.26 2.03 1.44 3.31 0.10 16.75 19.31 2.02 99.28MOX-25-161.5C Clinopyroxene High-Cr 6 Rim 54.21 0.26 1.89 1.28 3.25 0.08 16.94 19.77 1.82 99.51MOX-25-161.5C Clinopyroxene High-Cr 7 Rim 54.49 0.24 2.12 1.33 3.29 0.10 16.97 19.58 1.96 100.07MOX-25-161.5C Clinopyroxene High-Cr 8 Rim 54.63 0.24 1.93 1.41 3.21 0.15 17.17 19.64 1.85 100.22MOX-25-161.5C Clinopyroxene High-Cr 9 Rim 53.79 0.22 1.95 1.36 3.40 0.11 16.97 19.47 1.80 99.06MOX-25-161.5C Clinopyroxene High-Cr 10 Rim 54.21 0.27 1.91 1.19 3.28 0.11 17.15 19.44 1.77 99.33MOX-24-209.7 Clinopyroxene Low-Cr 1 Rim 53.99 0.19 1.57 0.46 3.27 0.15 16.79 21.85 1.47 99.74MOX-24-209.7 Clinopyroxene Low-Cr 2 Rim 54.39 0.19 1.63 0.47 3.19 0.13 16.80 21.67 1.39 99.87MOX-24-209.7 Clinopyroxene Low-Cr 3 Rim 54.74 0.21 1.54 0.49 3.17 0.08 16.88 21.94 1.44 100.48MOX-24-209.7 Clinopyroxene Low-Cr 4 Rim 54.84 0.17 1.47 0.56 3.31 0.09 16.89 21.66 1.45 100.45MOX-24-209.7 Clinopyroxene Low-Cr 5 Rim 53.97 0.19 1.58 0.46 3.17 0.09 16.78 21.59 1.44 99.26MOX-24-209.7 Clinopyroxene Low-Cr 6 Core 54.73 0.19 1.62 0.54 3.28 16.82 21.84 1.41 100.43MOX-24-209.7 Clinopyroxene Low-Cr 7 Core 54.70 0.18 1.70 0.45 3.23 0.13 17.07 21.95 1.38 100.80MOX-24-209.7 Clinopyroxene Low-Cr 8 Core 54.54 0.20 1.36 0.49 3.09 0.12 17.16 21.75 1.29 100.00MOX-24-209.7 Clinopyroxene Low-Cr 9 Core 54.22 0.15 1.58 0.49 3.17 0.08 16.94 21.81 1.40 99.85MOX-24-209.7 Clinopyroxene Low-Cr 10 Core 54.13 0.20 1.66 0.51 3.20 0.09 16.88 21.62 1.34 99.63MOX-1-43.35 Clinopyroxene Low-Cr 1 Rim 54.28 0.19 1.64 0.54 3.20 16.68 21.58 1.42 99.53MOX-1-43.35 Clinopyroxene Low-Cr 2 Rim 54.06 0.19 1.67 0.52 3.24 0.08 16.79 21.73 1.25 99.52MOX-1-43.35 Clinopyroxene Low-Cr 3 Rim 54.80 0.20 1.59 0.57 3.27 0.13 16.93 21.66 1.30 100.46MOX-1-43.35 Clinopyroxene Low-Cr 4 Rim 53.40 0.17 1.59 0.60 3.26 16.94 21.66 1.24 98.86MOX-1-43.35 Clinopyroxene Low-Cr 5 Rim 54.45 0.19 1.61 0.50 3.29 16.93 21.77 1.32 100.07MOX-1-43.35 Clinopyroxene Low-Cr 6 Core 54.10 0.21 1.66 0.59 3.14 0.14 17.03 21.70 1.39 99.97MOX-1-43.35 Clinopyroxene Low-Cr 7 Core 54.02 0.19 1.64 0.49 3.20 16.83 21.72 1.47 99.56MOX-1-43.35 Clinopyroxene Low-Cr 8 Core 55.10 0.19 1.64 0.57 3.25 0.13 16.93 22.15 1.40 101.36MOX-1-43.35 Clinopyroxene Low-Cr 9 Core 53.93 0.18 1.56 0.54 3.36 0.10 17.14 21.84 1.25 99.90MOX-1-43.35 Clinopyroxene Low-Cr 10 Core 53.66 0.22 1.65 0.63 3.34 0.10 16.90 21.71 1.43 99.64Empty cells indicate concentrations that were below minimum detection levelsAppendix B: Major Element Analyses of Megacrysts96Point Number Point Area O (apfu) Si (apfu) Ti (apfu) Al (apfu) Cr (apfu) Fe (apfu) Mn (apfu) Mg (apfu) Ca (apfu) Na (apfu) TotalMUSK-3-202.4 Clinopyroxene High-Cr 1 Core 6.000 1.990 0.007 0.081 0.031 0.100 0.004 0.926 0.749 0.118 4.004MUSK-3-202.4 Clinopyroxene High-Cr 2 Core 6.000 1.982 0.007 0.075 0.031 0.106 0.004 0.935 0.757 0.121 4.017MUSK-3-202.4 Clinopyroxene High-Cr 3 Core 6.000 1.984 0.007 0.075 0.028 0.109 0.003 0.936 0.754 0.120 4.015MUSK-3-202.4 Clinopyroxene High-Cr 4 Core 6.000 1.980 0.006 0.078 0.028 0.102 0.003 0.938 0.770 0.110 4.014MUSK-3-202.4 Clinopyroxene High-Cr 5 Core 6.000 1.976 0.007 0.076 0.031 0.104 0.004 0.935 0.774 0.118 4.022MUSK-3-202.4 Clinopyroxene High-Cr 6 Core 6.000 1.973 0.007 0.077 0.030 0.103 0.005 0.934 0.780 0.115 4.023MUSK-3-202.4 Clinopyroxene High-Cr 7 Core 6.000 1.979 0.007 0.077 0.031 0.105 0.003 0.942 0.760 0.115 4.017MUSK-3-202.4 Clinopyroxene High-Cr 8 Rim 6.000 1.981 0.006 0.078 0.029 0.103 0.003 0.936 0.764 0.114 4.014MUSK-3-202.4 Clinopyroxene High-Cr 9 Rim 6.000 1.975 0.007 0.081 0.033 0.107 0.003 0.926 0.762 0.131 4.026MUSK-3-202.4 Clinopyroxene High-Cr 10 Rim 6.000 1.982 0.006 0.078 0.031 0.106 0.005 0.921 0.770 0.120 4.017MUSK-3-202.4 Clinopyroxene High-Cr 11 Rim 6.000 1.983 0.007 0.077 0.030 0.100 0.003 0.939 0.761 0.110 4.010MUSK-3-202.4 Clinopyroxene High-Cr 12 Rim 6.000 1.976 0.006 0.077 0.031 0.108 0.004 0.928 0.772 0.118 4.021MUSK-3-202.4 Clinopyroxene High-Cr 13 Rim 6.000 1.980 0.006 0.075 0.028 0.105 0.002 0.935 0.771 0.121 4.023MUSK-3-202.4 Clinopyroxene High-Cr 14 Rim 6.000 1.955 0.007 0.079 0.033 0.106 0.003 0.954 0.785 0.118 4.040MUSK-3-202.4 Clinopyroxene High-Cr 15 Rim 6.000 1.973 0.007 0.078 0.031 0.107 0.003 0.944 0.763 0.116 4.023MUSK-3-202.4 Clinopyroxene High-Cr 16 Rim 6.000 1.985 0.007 0.078 0.030 0.108 0.004 0.923 0.765 0.114 4.011MOX-24-124A Clinopyroxene High-Cr 1 Core 6.000 1.965 0.006 0.084 0.039 0.095 0.003 0.931 0.781 0.120 4.025MOX-24-124A Clinopyroxene High-Cr 2 Core 6.000 1.968 0.007 0.080 0.042 0.099 0.003 0.932 0.768 0.125 4.024MOX-24-124A Clinopyroxene High-Cr 3 Core 6.000 1.979 0.007 0.084 0.036 0.100 0.005 0.920 0.757 0.130 4.018MOX-24-124A Clinopyroxene High-Cr 4 Core 6.000 1.972 0.008 0.086 0.042 0.100 0.004 0.930 0.739 0.142 4.023MOX-24-124A Clinopyroxene High-Cr 5 Core 6.000 1.983 0.008 0.087 0.037 0.103 0.004 0.915 0.745 0.133 4.013MOX-24-124A Clinopyroxene High-Cr 6 Core 6.000 1.975 0.007 0.087 0.034 0.103 0.004 0.930 0.754 0.124 4.018MOX-24-124A Clinopyroxene High-Cr 7 Core 6.000 1.977 0.007 0.086 0.030 0.102 0.003 0.932 0.753 0.133 4.023MOX-24-124A Clinopyroxene High-Cr 8 Core 6.000 1.980 0.007 0.087 0.036 0.101 0.004 0.924 0.745 0.131 4.015MOX-24-124A Clinopyroxene High-Cr 9 Core 6.000 1.980 0.007 0.086 0.030 0.104 0.005 0.928 0.748 0.131 4.019MOX-24-124A Clinopyroxene High-Cr 10 Core 6.000 1.977 0.007 0.083 0.032 0.101 0.003 0.939 0.747 0.134 4.024MOX-24-124A Clinopyroxene High-Cr 11 Rim 6.000 1.977 0.007 0.081 0.038 0.098 0.004 0.925 0.765 0.123 4.017MOX-24-124A Clinopyroxene High-Cr 12 Rim 6.000 1.977 0.008 0.082 0.038 0.097 0.002 0.925 0.763 0.127 4.019MOX-24-124A Clinopyroxene High-Cr 13 Rim 6.000 1.967 0.007 0.081 0.038 0.102 0.003 0.929 0.775 0.126 4.027MOX-24-124A Clinopyroxene High-Cr 14 Rim 6.000 1.971 0.007 0.080 0.036 0.101 0.930 0.779 0.117 4.020MOX-24-124A Clinopyroxene High-Cr 15 Rim 6.000 1.978 0.007 0.079 0.036 0.097 0.003 0.923 0.768 0.129 4.020MOX-24-124A Clinopyroxene High-Cr 16 Rim 6.000 1.969 0.006 0.082 0.035 0.097 0.004 0.933 0.776 0.126 4.028MOX-24-124A Clinopyroxene High-Cr 17 Rim 6.000 1.973 0.006 0.081 0.040 0.098 0.004 0.921 0.773 0.130 4.025MOX-24-124A Clinopyroxene High-Cr 18 Rim 6.000 1.976 0.007 0.086 0.036 0.105 0.003 0.927 0.749 0.130 4.020MOX-24-124A Clinopyroxene High-Cr 19 Rim 6.000 1.981 0.007 0.083 0.036 0.100 0.004 0.919 0.756 0.132 4.017MOX-24-124A Clinopyroxene High-Cr 20 Rim 6.000 1.978 0.007 0.078 0.037 0.100 0.002 0.922 0.768 0.128 4.020MOX-24-124A Clinopyroxene High-Cr 21 Rim 6.000 1.975 0.007 0.077 0.038 0.099 0.003 0.922 0.773 0.128 4.023MOX-24-124A Clinopyroxene High-Cr 22 Rim 6.000 1.975 0.008 0.078 0.035 0.102 0.003 0.925 0.769 0.128 4.023MOX-24-124A Clinopyroxene High-Cr 23 Rim 6.000 1.976 0.007 0.080 0.037 0.100 0.004 0.919 0.771 0.125 4.020MOX-24-124A Clinopyroxene High-Cr 24 Rim 6.000 1.977 0.008 0.078 0.037 0.098 0.004 0.926 0.767 0.124 4.018MUSK-3-158.8 Clinopyroxene High-Cr 1 Rim 6.000 1.972 0.007 0.082 0.022 0.101 0.003 0.925 0.797 0.116 4.025MUSK-3-158.8 Clinopyroxene High-Cr 2 Rim 6.000 1.968 0.007 0.084 0.020 0.101 0.004 0.921 0.813 0.111 4.027MUSK-3-158.8 Clinopyroxene High-Cr 3 Rim 6.000 1.968 0.007 0.085 0.021 0.098 0.002 0.927 0.806 0.111 4.026MUSK-3-158.8 Clinopyroxene High-Cr 4 Rim 6.000 1.959 0.007 0.085 0.021 0.100 0.005 0.934 0.815 0.109 4.035MUSK-3-158.8 Clinopyroxene High-Cr 5 Rim 6.000 1.966 0.005 0.083 0.024 0.098 0.003 0.923 0.813 0.121 4.035MUSK-3-158.8 Clinopyroxene High-Cr 6 Core 6.000 1.976 0.008 0.083 0.023 0.098 0.004 0.912 0.798 0.118 4.021MUSK-3-158.8 Clinopyroxene High-Cr 7 Core 6.000 1.973 0.006 0.082 0.023 0.101 0.003 0.913 0.811 0.112 4.023MUSK-3-158.8 Clinopyroxene High-Cr 8 Core 6.000 1.974 0.007 0.083 0.021 0.098 0.004 0.913 0.807 0.117 4.024MUSK-3-158.8 Clinopyroxene High-Cr 9 Core 6.000 1.983 0.006 0.084 0.022 0.099 0.002 0.906 0.801 0.114 4.015MUSK-3-158.8 Clinopyroxene High-Cr 10 Core 6.000 1.971 0.007 0.082 0.023 0.101 0.003 0.912 0.811 0.116 4.027MUSK-3-198.37 Clinopyroxene High-Cr 1 Rim 6.000 1.973 0.007 0.086 0.029 0.104 0.003 0.919 0.781 0.119 4.020MUSK-3-198.37 Clinopyroxene High-Cr 2 Rim 6.000 1.969 0.006 0.084 0.026 0.102 0.003 0.929 0.782 0.133 4.035MUSK-3-198.37 Clinopyroxene High-Cr 3 Rim 6.000 1.973 0.007 0.083 0.029 0.102 0.002 0.924 0.783 0.118 4.022MUSK-3-198.37 Clinopyroxene High-Cr 4 Rim 6.000 1.969 0.008 0.085 0.030 0.100 0.004 0.928 0.780 0.124 4.027MUSK-3-198.37 Clinopyroxene High-Cr 5 Rim 6.000 1.974 0.006 0.084 0.029 0.102 0.003 0.923 0.777 0.132 4.029MUSK-3-198.37 Clinopyroxene High-Cr 6 Core 6.000 1.972 0.006 0.081 0.030 0.103 0.004 0.924 0.790 0.116 4.024MUSK-3-198.37 Clinopyroxene High-Cr 7 Core 6.000 1.971 0.006 0.086 0.030 0.101 0.002 0.919 0.780 0.131 4.027MUSK-3-198.37 Clinopyroxene High-Cr 8 Core 6.000 1.968 0.007 0.085 0.031 0.102 0.004 0.929 0.785 0.110 4.022MUSK-3-198.37 Clinopyroxene High-Cr 9 Core 6.000 1.967 0.007 0.082 0.027 0.104 0.002 0.933 0.784 0.125 4.031MUSK-3-198.37 Clinopyroxene High-Cr 10 Core 6.000 1.970 0.007 0.085 0.028 0.103 0.004 0.925 0.784 0.121 4.026Appendix B: Major Element Analyses of Megacrysts Sample Mineral SuiteCation amounts for respective microprobe measurements. Empty cells indicate concentrations that were below minimum detection levels97Point Area O (apfu) Si (apfu) Ti (apfu) Al (apfu) Cr (apfu) Fe (apfu) Mn (apfu) Mg (apfu) Ca (apfu) Na (apfu) TotalMOX-24-34.3 Clinopyroxene High-Cr 1 Rim 6.000 1.959 0.007 0.081 0.036 0.100 0.003 0.947 0.775 0.134 4.042MOX-24-34.3 Clinopyroxene High-Cr 2 Rim 6.000 1.970 0.006 0.081 0.037 0.098 0.004 0.941 0.765 0.122 4.024MOX-24-34.3 Clinopyroxene High-Cr 3 Rim 6.000 1.975 0.007 0.083 0.036 0.098 0.004 0.929 0.764 0.120 4.016MOX-24-34.3 Clinopyroxene High-Cr 4 Rim 6.000 1.956 0.007 0.083 0.038 0.098 0.003 0.958 0.771 0.122 4.037MOX-24-34.3 Clinopyroxene High-Cr 5 Rim 6.000 1.976 0.006 0.077 0.036 0.092 0.003 0.943 0.769 0.117 4.018MOX-24-34.3 Clinopyroxene High-Cr 6 Core 6.000 1.969 0.007 0.080 0.036 0.095 0.005 0.931 0.778 0.132 4.032MOX-24-34.3 Clinopyroxene High-Cr 7 Core 6.000 1.980 0.006 0.083 0.038 0.100 0.003 0.919 0.759 0.131 4.019MOX-24-34.3 Clinopyroxene High-Cr 8 Core 6.000 1.979 0.006 0.078 0.037 0.098 0.004 0.921 0.776 0.117 4.015MOX-24-34.3 Clinopyroxene High-Cr 9 Core 6.000 1.973 0.006 0.079 0.039 0.100 0.002 0.930 0.768 0.131 4.026MOX-24-34.3 Clinopyroxene High-Cr 10 Core 6.000 1.973 0.006 0.081 0.037 0.095 0.003 0.933 0.772 0.119 4.019MOX-28-320.1 Clinopyroxene High-Cr 1 Rim 6.000 1.976 0.006 0.081 0.027 0.103 0.003 0.914 0.794 0.116 4.020MOX-28-320.1 Clinopyroxene High-Cr 2 Rim 6.000 1.979 0.008 0.083 0.024 0.099 0.002 0.922 0.781 0.122 4.020MOX-28-320.1 Clinopyroxene High-Cr 3 Rim 6.000 1.976 0.007 0.084 0.027 0.098 0.004 0.920 0.786 0.121 4.022MOX-28-320.1 Clinopyroxene High-Cr 4 Rim 6.000 1.975 0.005 0.076 0.026 0.102 0.003 0.929 0.793 0.113 4.022MOX-28-320.1 Clinopyroxene High-Cr 5 Rim 6.000 1.966 0.007 0.078 0.028 0.097 0.004 0.944 0.795 0.105 4.024MOX-28-320.1 Clinopyroxene High-Cr 6 Core 6.000 1.970 0.007 0.082 0.031 0.103 0.004 0.928 0.785 0.114 4.023MOX-28-320.1 Clinopyroxene High-Cr 7 Core 6.000 1.972 0.007 0.082 0.028 0.107 0.003 0.921 0.789 0.114 4.021MOX-28-320.1 Clinopyroxene High-Cr 8 Core 6.000 1.974 0.007 0.079 0.027 0.100 0.004 0.924 0.791 0.121 4.025MOX-28-320.1 Clinopyroxene High-Cr 9 Core 6.000 1.978 0.007 0.078 0.026 0.101 0.003 0.922 0.790 0.115 4.020MOX-28-320.1 Clinopyroxene High-Cr 10 Core 6.000 1.987 0.007 0.080 0.029 0.097 0.906 0.784 0.117 4.008MOX-25-161.5C Clinopyroxene High-Cr 1 Core 6.000 1.980 0.008 0.088 0.034 0.106 0.004 0.923 0.742 0.130 4.016MOX-25-161.5C Clinopyroxene High-Cr 2 Core 6.000 1.972 0.008 0.087 0.042 0.102 0.003 0.925 0.749 0.131 4.020MOX-25-161.5C Clinopyroxene High-Cr 3 Core 6.000 1.977 0.009 0.091 0.038 0.101 0.004 0.930 0.730 0.134 4.014MOX-25-161.5C Clinopyroxene High-Cr 4 Core 6.000 1.964 0.008 0.088 0.032 0.107 0.004 0.944 0.752 0.132 4.032MOX-25-161.5C Clinopyroxene High-Cr 5 Core 6.000 1.974 0.007 0.087 0.042 0.101 0.003 0.912 0.756 0.143 4.025MOX-25-161.5C Clinopyroxene High-Cr 6 Rim 6.000 1.975 0.007 0.081 0.037 0.099 0.003 0.920 0.772 0.129 4.021MOX-25-161.5C Clinopyroxene High-Cr 7 Rim 6.000 1.973 0.007 0.090 0.038 0.100 0.003 0.916 0.760 0.138 4.024MOX-25-161.5C Clinopyroxene High-Cr 8 Rim 6.000 1.975 0.007 0.082 0.040 0.097 0.005 0.925 0.761 0.129 4.021MOX-25-161.5C Clinopyroxene High-Cr 9 Rim 6.000 1.970 0.006 0.084 0.039 0.104 0.003 0.927 0.764 0.128 4.025MOX-25-161.5C Clinopyroxene High-Cr 10 Rim 6.000 1.976 0.007 0.082 0.034 0.100 0.004 0.932 0.759 0.125 4.020MOX-24-209.7 Clinopyroxene Low-Cr 1 Rim 6.000 1.971 0.005 0.068 0.013 0.100 0.005 0.914 0.855 0.104 4.034MOX-24-209.7 Clinopyroxene Low-Cr 2 Rim 6.000 1.979 0.005 0.070 0.014 0.097 0.004 0.911 0.845 0.098 4.023MOX-24-209.7 Clinopyroxene Low-Cr 3 Rim 6.000 1.980 0.006 0.066 0.014 0.096 0.002 0.910 0.850 0.101 4.024MOX-24-209.7 Clinopyroxene Low-Cr 4 Rim 6.000 1.984 0.005 0.063 0.016 0.100 0.003 0.910 0.840 0.102 4.022MOX-24-209.7 Clinopyroxene Low-Cr 5 Rim 6.000 1.976 0.005 0.068 0.013 0.097 0.003 0.916 0.847 0.102 4.027MOX-24-209.7 Clinopyroxene Low-Cr 6 Core 6.000 1.980 0.005 0.069 0.016 0.099 0.907 0.847 0.099 4.021MOX-24-209.7 Clinopyroxene Low-Cr 7 Core 6.000 1.973 0.005 0.072 0.013 0.097 0.004 0.918 0.848 0.097 4.027MOX-24-209.7 Clinopyroxene Low-Cr 8 Core 6.000 1.980 0.005 0.058 0.014 0.094 0.004 0.929 0.846 0.091 4.021MOX-24-209.7 Clinopyroxene Low-Cr 9 Core 6.000 1.974 0.004 0.068 0.014 0.096 0.003 0.919 0.851 0.099 4.028MOX-24-209.7 Clinopyroxene Low-Cr 10 Core 6.000 1.974 0.006 0.072 0.015 0.098 0.003 0.917 0.845 0.095 4.023MOX-1-43.35 Clinopyroxene Low-Cr 1 Rim 6.000 1.980 0.005 0.070 0.016 0.098 0.907 0.843 0.100 4.019MOX-1-43.35 Clinopyroxene Low-Cr 2 Rim 6.000 1.974 0.005 0.072 0.015 0.099 0.002 0.914 0.850 0.088 4.020MOX-1-43.35 Clinopyroxene Low-Cr 3 Rim 6.000 1.981 0.006 0.068 0.016 0.099 0.004 0.912 0.839 0.091 4.015MOX-1-43.35 Clinopyroxene Low-Cr 4 Rim 6.000 1.965 0.005 0.069 0.018 0.100 0.929 0.854 0.089 4.027MOX-1-43.35 Clinopyroxene Low-Cr 5 Rim 6.000 1.976 0.005 0.069 0.014 0.100 0.916 0.846 0.093 4.020MOX-1-43.35 Clinopyroxene Low-Cr 6 Core 6.000 1.969 0.006 0.071 0.017 0.096 0.004 0.924 0.846 0.098 4.030MOX-1-43.35 Clinopyroxene Low-Cr 7 Core 6.000 1.972 0.005 0.071 0.014 0.098 0.916 0.850 0.104 4.030MOX-1-43.35 Clinopyroxene Low-Cr 8 Core 6.000 1.977 0.005 0.069 0.016 0.098 0.004 0.906 0.852 0.098 4.024MOX-1-43.35 Clinopyroxene Low-Cr 9 Core 6.000 1.966 0.005 0.067 0.016 0.103 0.003 0.931 0.853 0.088 4.032MOX-1-43.35 Clinopyroxene Low-Cr 10 Core 6.000 1.963 0.006 0.071 0.018 0.102 0.003 0.922 0.851 0.101 4.037Cation amounts for respective microprobe measurements. Empty cells indicate concentrations that were below minimum detection levelsAppendix B: Major Element Analyses of Megacrysts Sample Mineral Suite Point98Suite Point Area SiO2, wt.% TiO2, wt.% Al2O3,wt.% Cr2O3, wt.% FeO, wt.% MnO, wt.% MgO, wt.% CaO, wt.% Na2O, wt.% TotalMOX-24-230.7 Garnet High-Cr 1 Rim 41.22 0.61 20.05 4.34 9.72 0.45 19.53 5.04 0.09 101.04MOX-24-230.7 Garnet High-Cr 2 Rim 41.31 0.63 20.03 4.36 9.50 0.47 19.48 4.99 100.77MOX-24-230.7 Garnet High-Cr 3 Rim 41.07 0.64 20.07 4.40 9.66 0.52 19.45 4.99 100.81MOX-24-230.7 Garnet High-Cr 4 Rim 41.33 0.55 20.15 4.67 9.61 0.47 19.50 5.12 101.41MOX-24-230.7 Garnet High-Cr 5 Rim 40.77 0.61 20.07 4.32 9.73 0.47 19.23 5.04 100.23MOX-24-230.7 Garnet High-Cr 6 Core 40.32 0.71 18.54 5.50 9.48 0.53 18.53 5.52 99.12MOX-24-230.7 Garnet High-Cr 7 Core 40.60 0.65 19.13 5.42 9.70 0.45 18.92 5.36 100.23MOX-24-230.7 Garnet High-Cr 8 Core 40.64 0.67 19.50 4.44 9.73 0.53 18.98 5.00 99.50MOX-24-230.7 Garnet High-Cr 9 Core 40.70 0.61 19.59 4.41 9.97 0.52 19.21 5.07 100.09MOX-24-230.7 Garnet High-Cr 10 Core 40.57 0.66 18.89 5.24 10.02 0.46 18.88 5.29 100.01MOX-25-124.8 Garnet Low-Cr 1 Rim 41.53 0.20 22.53 0.87 8.74 0.18 19.22 6.13 99.39MOX-25-124.8 Garnet Low-Cr 2 Rim 41.84 0.20 22.29 1.12 8.80 0.19 18.92 6.27 99.64MOX-25-124.8 Garnet Low-Cr 3 Rim 41.61 0.19 22.42 0.75 8.83 0.22 19.34 5.76 99.12MOX-25-124.8 Garnet Low-Cr 4 Rim 41.92 0.23 23.16 0.47 9.00 0.19 20.17 5.47 100.61MOX-25-124.8 Garnet Low-Cr 5 Rim 42.11 0.21 22.88 0.64 8.95 0.19 19.62 5.74 100.34MOX-25-124.8 Garnet Low-Cr 6 Core 41.90 0.22 22.37 1.06 8.96 0.21 19.52 5.92 100.16MOX-25-124.8 Garnet Low-Cr 7 Core 41.72 0.18 22.41 0.91 8.81 0.22 19.31 6.08 99.65MOX-25-124.8 Garnet Low-Cr 8 Core 41.94 0.15 22.67 0.80 8.91 0.22 19.43 6.01 100.13MOX-25-124.8 Garnet Low-Cr 9 Core 41.67 0.17 22.18 1.02 8.91 0.21 19.21 6.22 99.61MOX-25-124.8 Garnet Low-Cr 10 Core 41.99 0.17 22.79 0.75 8.91 0.19 19.45 5.86 100.11Sample Mineral Suite Point Area O (apfu) Si (apfu) Ti (apfu) Al (apfu) Cr (apfu) Fe (apfu) Mn (apfu) Mg (apfu) Ca (apfu) Na (apfu) TotalMOX-24-230.7 Garnet High-Cr 1 Rim 12.000 2.961 0.033 1.697 0.246 0.584 0.027 2.092 0.388 0.013 8.041MOX-24-230.7 Garnet High-Cr 2 Rim 12.000 2.970 0.034 1.698 0.248 0.571 0.029 2.088 0.385 8.021MOX-24-230.7 Garnet High-Cr 3 Rim 12.000 2.956 0.035 1.703 0.250 0.582 0.032 2.086 0.385 8.029MOX-24-230.7 Garnet High-Cr 4 Rim 12.000 2.958 0.030 1.700 0.264 0.575 0.029 2.080 0.393 8.028MOX-24-230.7 Garnet High-Cr 5 Rim 12.000 2.953 0.033 1.713 0.247 0.589 0.029 2.076 0.391 8.032MOX-24-230.7 Garnet High-Cr 6 Core 12.000 2.969 0.040 1.609 0.320 0.584 0.033 2.034 0.435 8.025MOX-24-230.7 Garnet High-Cr 7 Core 12.000 2.954 0.036 1.640 0.312 0.590 0.028 2.052 0.418 8.030MOX-24-230.7 Garnet High-Cr 8 Core 12.000 2.968 0.037 1.678 0.256 0.595 0.033 2.066 0.391 8.024MOX-24-230.7 Garnet High-Cr 9 Core 12.000 2.958 0.034 1.679 0.254 0.606 0.032 2.081 0.395 8.038MOX-24-230.7 Garnet High-Cr 10 Core 12.000 2.963 0.036 1.625 0.303 0.612 0.029 2.054 0.414 8.036MOX-25-124.8 Garnet Low-Cr 1 Rim 12.000 2.986 0.011 1.909 0.050 0.525 0.011 2.060 0.472 8.024MOX-25-124.8 Garnet Low-Cr 2 Rim 12.000 3.004 0.011 1.886 0.064 0.529 0.012 2.025 0.482 8.011MOX-25-124.8 Garnet Low-Cr 3 Rim 12.000 2.997 0.010 1.903 0.042 0.532 0.014 2.076 0.445 8.020MOX-25-124.8 Garnet Low-Cr 4 Rim 12.000 2.971 0.012 1.935 0.026 0.534 0.012 2.131 0.415 8.036MOX-25-124.8 Garnet Low-Cr 5 Rim 12.000 2.994 0.011 1.917 0.036 0.532 0.011 2.080 0.437 8.019MOX-25-124.8 Garnet Low-Cr 6 Core 12.000 2.992 0.012 1.882 0.060 0.535 0.012 2.078 0.453 8.025MOX-25-124.8 Garnet Low-Cr 7 Core 12.000 2.993 0.010 1.895 0.052 0.529 0.013 2.065 0.468 8.024MOX-25-124.8 Garnet Low-Cr 8 Core 12.000 2.993 0.008 1.907 0.045 0.532 0.013 2.067 0.459 8.024MOX-25-124.8 Garnet Low-Cr 9 Core 12.000 2.995 0.010 1.879 0.058 0.536 0.013 2.058 0.479 8.027MOX-25-124.8 Garnet Low-Cr 10 Core 12.000 2.994 0.009 1.915 0.042 0.532 0.012 2.067 0.448 8.018 Sample MineralEmpty cells indicate concentrations that were below minimum detection levelsCation amounts for respective microprobe measurements. Empty cells indicate concentrations that were below minimum detection levelsAppendix B. Major Element Analyses of Megacrysts 99Sample Mineral Suite No Spot SiO2, wt% TiO2, wt% Al2O3,wt% Cr2O3, wt% FeO, wt% MnO, wt% MgO, wt% CaO, wt% NiO, wt% Total MOX-24-102.8 Olivine Low-Cr 1 Rim 40.89 0.09 9.86 0.14 49.92 0.31 101.20MOX-24-102.8 Olivine Low-Cr 2 Rim 41.04 10.07 0.12 49.32 0.35 100.90MOX-24-102.8 Olivine Low-Cr 3 Rim 40.76 9.99 0.11 49.95 0.37 101.17MOX-24-102.8 Olivine Low-Cr 4 Rim 41.43 0.07 9.78 0.11 50.25 0.30 101.93MOX-24-102.8 Olivine Low-Cr 5 Rim 40.63 9.96 0.10 49.20 0.37 100.26MOX-24-102.8 Olivine Low-Cr 6 Core 40.38 0.06 9.90 0.11 49.46 0.40 100.31MOX-24-102.8 Olivine Low-Cr 7 Core 40.67 9.92 0.08 49.64 0.39 100.69MOX-24-102.8 Olivine Low-Cr 8 Core 41.02 9.97 0.17 49.65 0.03 0.31 101.16MOX-24-102.8 Olivine Low-Cr 9 Core 40.99 0.06 10.02 0.15 49.63 0.04 0.35 101.25MOX-24-102.8 Olivine Low-Cr 10 Core 40.71 9.81 0.11 49.69 0.35 100.68MOX-25-161.5G Olivine Low-Cr 1 Rim 40.30 0.06 10.37 0.11 49.06 0.28 100.19MOX-25-161.5G Olivine Low-Cr 2 Rim 40.69 10.78 0.11 48.65 0.20 100.43MOX-25-161.5G Olivine Low-Cr 3 Rim 40.58 0.05 10.52 0.13 48.73 0.33 100.34MOX-25-161.5G Olivine Low-Cr 4 Rim 40.71 10.58 0.10 48.85 0.04 0.37 100.66MOX-25-161.5G Olivine Low-Cr 5 Rim 40.71 10.19 0.14 48.90 0.27 100.21MOX-25-161.5G Olivine Low-Cr 6 Core 40.84 10.46 0.15 48.75 0.05 0.25 100.51MOX-25-161.5G Olivine Low-Cr 7 core 40.25 10.47 0.07 48.83 0.05 0.29 99.96MOX-25-161.5G Olivine Low-Cr 8 Core 40.70 10.63 0.08 49.24 0.04 0.24 100.93MOX-25-161.5G Olivine Low-Cr 9 Core 40.66 10.61 0.06 49.16 0.26 100.75MOX-25-161.5G Olivine Low-Cr 10 Core 40.66 10.85 0.14 48.94 0.28 100.87MOX-24-42.6 Olivine Low-Cr 1 Rim 40.91 0.06 10.09 0.11 49.73 0.33 101.22MOX-24-42.6 Olivine Low-Cr 2 Rim 40.52 0.06 10.33 0.12 49.23 0.06 0.31 100.62MOX-24-42.6 Olivine Low-Cr 3 Rim 40.73 0.05 10.28 0.18 49.49 0.04 0.32 101.09MOX-24-42.6 Olivine Low-Cr 4 Rim 40.51 10.33 0.15 49.38 0.28 100.65Sample Mineral Suite No Spot O Si Ti Al Cr Fe Mn Mg Ca Ni TotalMOX-24-102.8 Olivine Low-Cr 1 Rim 4.000 0.992 0.002 0.200 0.003 1.804 0.006 3.006MOX-24-102.8 Olivine Low-Cr 2 Rim 4.000 0.998 0.205 0.003 1.788 0.007 3.000MOX-24-102.8 Olivine Low-Cr 3 Rim 4.000 0.990 0.203 0.002 1.807 0.007 3.009MOX-24-102.8 Olivine Low-Cr 4 Rim 4.000 0.996 0.001 0.197 0.002 1.800 0.006 3.002MOX-24-102.8 Olivine Low-Cr 5 Rim 4.000 0.994 0.204 0.002 1.795 0.007 3.003MOX-24-102.8 Olivine Low-Cr 6 Core 4.000 0.989 0.001 0.203 0.002 1.805 0.008 3.008MOX-24-102.8 Olivine Low-Cr 7 Core 4.000 0.991 0.202 0.002 1.804 0.008 3.007MOX-24-102.8 Olivine Low-Cr 8 Core 4.000 0.995 0.202 0.004 1.794 0.001 0.006 3.002MOX-24-102.8 Olivine Low-Cr 9 Core 4.000 0.994 0.001 0.203 0.003 1.794 0.001 0.007 3.004MOX-24-102.8 Olivine Low-Cr 10 Core 4.000 0.992 0.200 0.002 1.805 0.007 3.006MOX-25-161.5G Olivine Low-Cr 1 Rim 4.000 0.990 0.001 0.213 0.002 1.795 0.006 3.007MOX-25-161.5G Olivine Low-Cr 2 Rim 4.000 0.997 0.221 0.002 1.776 0.004 3.000MOX-25-161.5G Olivine Low-Cr 3 Rim 4.000 0.995 0.001 0.216 0.003 1.781 0.007 3.003MOX-25-161.5G Olivine Low-Cr 4 Rim 4.000 0.995 0.216 0.002 1.780 0.001 0.007 3.002MOX-25-161.5G Olivine Low-Cr 5 Rim 4.000 0.997 0.209 0.003 1.786 0.005 3.000MOX-25-161.5G Olivine Low-Cr 6 Core 4.000 0.999 0.214 0.003 1.777 0.001 0.005 2.999MOX-25-161.5G Olivine Low-Cr 7 core 4.000 0.991 0.216 0.002 1.792 0.001 0.006 3.007MOX-25-161.5G Olivine Low-Cr 8 Core 4.000 0.992 0.217 0.002 1.789 0.001 0.005 3.005MOX-25-161.5G Olivine Low-Cr 9 Core 4.000 0.992 0.217 0.001 1.789 0.005 3.004MOX-25-161.5G Olivine Low-Cr 10 Core 4.000 0.993 0.221 0.003 1.781 0.006 3.003MOX-24-42.6 Olivine Low-Cr 1 Rim 4.000 1.489 0.002 0.307 0.004 2.697 0.010 3.019MOX-24-42.6 Olivine Low-Cr 2 Rim 4.000 1.486 0.002 0.317 0.004 2.691 0.002 0.009 3.025MOX-24-42.6 Olivine Low-Cr 3 Rim 4.000 1.486 0.001 0.314 0.006 2.692 0.002 0.009 3.023MOX-24-42.6 Olivine Low-Cr 4 Rim 4.000 1.485 0.317 0.005 2.698 0.008 3.028Empty cells indicate concentrations that were below minimum detection levelsCation amounts for respective microprobe measurements. Empty cells indicate concentrations that were below minimum detection levels. Appendix B. Major Element Analyses of Megacrysts 100Sample Mineral Suite Point Area SiO2, wt.% TiO2, wt.% Al2O3,wt.% Cr2O3, wt.% FeOT, wt.% MnO, wt.% MgO, wt.% CaO, wt.% NbO, wt.% TotalMOX-24-206.97 Ilmenite Low-Cr 1 Rim 52.92 2.52 31.65 0.30 12.19 0.04 0.17 99.79MOX-24-206.97 Ilmenite Low-Cr 2 Rim 52.90 2.40 31.81 0.30 12.19 0.24 99.85MOX-24-206.97 Ilmenite Low-Cr 3 Rim 52.31 0.11 2.53 31.82 0.28 12.18 0.19 99.42MOX-24-206.97 Ilmenite Low-Cr 4 Rim 52.50 2.49 31.96 0.30 12.24 99.50MOX-24-206.97 Ilmenite Low-Cr 5 Rim 52.29 0.11 2.52 32.18 0.28 12.14 0.18 99.70MOX-24-206.97 Ilmenite Low-Cr 6 Core 52.39 0.16 2.45 31.83 0.28 12.38 0.15 99.64MOX-24-206.97 Ilmenite Low-Cr 7 Core 52.39 2.34 32.37 0.26 12.20 99.56MOX-24-206.97 Ilmenite Low-Cr 8 Core 52.16 0.11 2.40 31.53 0.34 12.01 98.56MOX-24-206.97 Ilmenite Low-Cr 9 Core 52.36 2.44 32.11 0.30 12.13 99.34MOX-24-206.97 Ilmenite Low-Cr 10 Core 52.57 0.10 2.34 31.57 0.28 12.25 99.11MOX-24-206.97 Ilmenite Low-Cr 11 Spongy 52.53 0.10 2.40 31.79 0.25 11.91 98.98MOX-24-206.97 Ilmenite Low-Cr 12 Spongy 52.43 2.36 31.98 0.29 11.95 0.17 99.17MOX-24-206.97 Ilmenite Low-Cr 13 Spongy 52.31 0.09 2.35 31.73 0.34 12.25 0.21 99.28MOX-24-206.97 Ilmenite Low-Cr 14 Spongy 52.52 0.10 2.45 31.72 0.28 12.19 99.26MOX-24-206.97 Ilmenite Low-Cr 15 Spongy 52.54 2.41 32.17 0.29 12.13 0.16 99.70MOX-24-209.7 Ilmenite Low-Cr 1 Rim 0.0632 52.83 0.10 1.97 32.40 0.27 11.79 99.42MOX-24-209.7 Ilmenite Low-Cr 2 Rim 52.57 0.17 1.86 32.56 0.24 11.70 0.16 99.26MOX-24-209.7 Ilmenite Low-Cr 3 Rim 52.36 1.97 32.11 0.31 11.85 0.20 98.81MOX-24-209.7 Ilmenite Low-Cr 4 Rim 52.60 0.18 2.02 32.19 0.30 11.88 0.04 0.14 99.35MOX-24-209.7 Ilmenite Low-Cr 5 Rim 53.17 0.11 1.99 31.10 0.31 12.73 99.42MOX-24-209.7 Ilmenite Low-Cr 6 Core 52.76 2.01 32.18 0.26 12.10 0.22 99.52MOX-24-209.7 Ilmenite Low-Cr 7 Core 52.70 0.13 2.25 32.19 0.27 12.09 0.19 99.82MOX-24-209.7 Ilmenite Low-Cr 8 Core 52.40 0.11 2.10 32.31 0.27 11.70 0.18 99.07MOX-24-209.7 Ilmenite Low-Cr 9 Core 52.31 0.19 2.00 32.55 0.28 11.97 0.16 99.46MOX-24-209.7 Ilmenite Low-Cr 10 Core 52.67 0.12 1.95 32.51 0.17 11.88 0.16 99.47MOX-28-308 Ilmenite Low-Cr 1 Rim 52.53 0.13 2.86 30.93 0.22 12.44 99.11MOX-28-308 Ilmenite Low-Cr 2 Rim 0.0659 51.99 0.09 2.99 31.32 0.28 12.13 98.88MOX-28-308 Ilmenite Low-Cr 3 Rim 52.47 3.03 31.49 0.21 12.36 0.17 99.72MOX-28-308 Ilmenite Low-Cr 4 Rim 52.32 0.12 2.88 30.80 0.24 12.41 0.04 0.15 98.97MOX-28-308 Ilmenite Low-Cr 5 Rim 0.0666 52.41 0.13 2.90 30.94 0.28 12.43 0.23 99.39MOX-28-308 Ilmenite Low-Cr 6 Core 52.14 0.11 2.94 31.28 0.28 12.43 0.16 99.33MOX-28-308 Ilmenite Low-Cr 7 Core 52.41 0.10 2.85 31.27 0.29 12.45 0.04 0.15 99.56MOX-28-308 Ilmenite Low-Cr 8 Core 52.21 0.11 3.00 31.41 0.30 12.53 99.54MOX-28-308 Ilmenite Low-Cr 9 Core 51.96 0.11 3.12 31.44 0.29 12.37 0.15 99.44MOX-28-308 Ilmenite Low-Cr 10 Core 52.59 0.13 3.02 30.95 0.32 12.45 0.04 0.14 99.63MOX-28-308 Ilmenite Low-Cr 11 Spongy 52.03 0.11 2.91 30.89 0.26 12.40 98.60MOX-28-308 Ilmenite Low-Cr 12 Spongy 52.48 0.15 2.91 31.01 0.25 12.44 99.25MOX-28-308 Ilmenite Low-Cr 13 Spongy 52.59 3.00 31.31 0.26 12.16 99.32MOX-28-308 Ilmenite Low-Cr 14 Spongy 52.23 0.14 2.80 31.40 0.30 12.41 99.27MOX-28-308 Ilmenite Low-Cr 15 Spongy 52.57 0.17 2.88 30.85 0.32 12.48 99.28MOX-3-74.4 Ilmenite Low-Cr 1 Rim 52.61 2.16 32.10 0.28 12.27 99.41MOX-3-74.4 Ilmenite Low-Cr 2 Rim 52.07 2.29 32.08 0.32 12.14 98.91MOX-3-74.4 Ilmenite Low-Cr 3 Rim 52.26 0.09 2.30 32.09 0.34 12.02 0.18 99.28MOX-3-74.4 Ilmenite Low-Cr 4 Rim 52.36 0.12 2.27 31.98 0.33 12.32 99.38MOX-3-74.4 Ilmenite Low-Cr 5 Rim 0.0612 52.47 2.23 32.42 0.26 12.27 99.71MOX-3-74.4 Ilmenite Low-Cr 6 Core 52.72 0.13 2.19 31.67 0.34 12.07 99.12MOX-3-74.4 Ilmenite Low-Cr 7 Core 52.64 2.11 31.71 0.30 12.00 98.77MOX-3-74.4 Ilmenite Low-Cr 8 Core 52.92 0.14 2.30 31.78 0.34 12.06 0.18 99.72MOX-3-74.4 Ilmenite Low-Cr 9 Core 52.56 0.16 2.40 31.73 0.34 12.11 0.16 99.47MOX-3-74.4 Ilmenite Low-Cr 10 Core 52.33 2.32 31.93 0.35 11.97 98.91MOX-3-74.4 Ilmenite Low-Cr 11 Spongy 52.32 2.16 32.00 0.32 12.21 0.16 99.16MOX-3-74.4 Ilmenite Low-Cr 12 Spongy 53.06 0.13 2.19 31.84 0.26 12.04 0.22 99.72MOX-3-74.4 Ilmenite Low-Cr 13 Spongy 52.21 0.24 2.23 31.76 0.32 12.35 0.22 99.33MOX-3-74.4 Ilmenite Low-Cr 14 Spongy 52.73 2.39 31.18 0.31 12.98 0.07 0.22 99.88MOX-3-74.4 Ilmenite Low-Cr 15 Spongy 52.43 0.18 2.18 32.03 0.34 12.22 0.21 99.58Empty cells indicate concentrations that were below minimum detection levelsAppendix B. Major Element Analyses of Megacrysts 101Sample Mineral Suite Point Area SiO2, wt.% TiO2, wt.% Al2O3,wt.% Cr2O3, wt.% FeOT, wt.% MnO, wt.% MgO, wt.% CaO, wt.% NbO, wt.% TotalMOX-25-65.16 Ilmenite Low-Cr 1 Rim 51.63 1.64 34.09 0.32 11.31 0.25 99.24MOX-25-65.16 Ilmenite Low-Cr 2 Rim 52.54 1.71 32.83 0.34 12.18 0.31 99.92MOX-25-65.16 Ilmenite Low-Cr 3 Rim 52.14 1.69 34.02 0.32 11.57 0.34 100.10MOX-25-65.16 Ilmenite Low-Cr 4 Rim 51.62 1.67 34.40 0.33 11.17 0.18 99.37MOX-25-65.16 Ilmenite Low-Cr 5 Rim 51.44 1.82 34.44 0.37 10.98 0.28 99.33MOX-25-65.16 Ilmenite Low-Cr 6 Core 51.52 1.75 34.68 0.29 11.13 0.21 99.59MOX-25-65.16 Ilmenite Low-Cr 7 Core 51.51 1.70 34.66 0.34 11.13 0.20 99.54MOX-25-65.16 Ilmenite Low-Cr 8 Core 51.59 1.60 34.60 0.30 11.23 0.04 0.22 99.58MOX-25-65.16 Ilmenite Low-Cr 9 Core 51.66 1.57 34.11 0.35 11.24 0.16 99.10MOX-25-65.16 Ilmenite Low-Cr 10 Core 51.62 1.63 34.74 0.34 11.08 0.28 99.69MOX-25-65.16 Ilmenite Low-Cr 11 Zoning 51.29 1.62 34.61 0.30 11.19 0.19 99.20MOX-25-65.16 Ilmenite Low-Cr 12 Zoning 51.55 1.68 34.29 0.31 11.23 0.21 99.27MOX-25-65.16 Ilmenite Low-Cr 13 Zoning 51.26 1.67 34.68 0.31 11.14 0.18 99.24MOX-25-65.16 Ilmenite Low-Cr 14 Zoning 51.34 1.64 34.17 0.36 11.20 0.20 98.90MOX-25-65.16 Ilmenite Low-Cr 15 Zoning 51.35 1.58 34.67 0.38 11.23 0.23 99.45MOX-24-206.73 Ilmenite Low-Cr 1 Rim 51.85 1.62 34.13 0.36 11.62 99.57MOX-24-206.73 Ilmenite Low-Cr 2 Rim 52.13 1.64 32.88 0.31 12.48 0.24 99.68MOX-24-206.73 Ilmenite Low-Cr 3 Rim 52.64 1.47 32.58 0.31 12.48 0.16 99.64MOX-24-206.73 Ilmenite Low-Cr 4 Rim 52.15 1.48 34.31 0.29 11.25 0.06 0.22 99.76MOX-24-206.73 Ilmenite Low-Cr 5 Rim 52.10 1.57 34.17 0.25 11.27 99.37MOX-24-206.73 Ilmenite Low-Cr 6 Core 51.69 1.64 34.77 0.32 11.21 0.26 99.90MOX-24-206.73 Ilmenite Low-Cr 7 Core 51.90 1.67 33.93 0.37 11.28 0.22 99.38MOX-24-206.73 Ilmenite Low-Cr 8 Core 51.64 1.56 34.09 0.31 11.22 0.17 98.99MOX-24-206.73 Ilmenite Low-Cr 9 Core 51.67 1.66 34.26 0.30 11.33 99.23MOX-24-206.73 Ilmenite Low-Cr 10 Core 51.93 1.63 34.50 0.35 11.11 0.25 99.78MOX-25-120.6A Ilmenite Low-Cr 1 Rim 51.76 1.67 34.19 0.37 11.46 0.21 99.64MOX-25-120.6A Ilmenite Low-Cr 2 Rim 51.64 1.73 34.25 0.35 11.46 0.28 99.71MOX-25-120.6A Ilmenite Low-Cr 3 Rim 52.22 1.65 33.35 0.31 11.06 0.18 98.77MOX-25-120.6A Ilmenite Low-Cr 4 Rim 52.22 1.63 33.94 0.37 10.96 0.23 99.35MOX-25-120.6A Ilmenite Low-Cr 5 Rim 51.70 1.65 34.24 0.28 11.18 0.23 99.29MOX-25-120.6A Ilmenite Low-Cr 6 Zoning 51.85 1.68 34.03 0.34 11.33 0.25 99.48MOX-25-120.6A Ilmenite Low-Cr 7 Core 51.69 1.53 34.34 0.29 11.06 0.26 99.18MOX-25-120.6A Ilmenite Low-Cr 8 Core 51.77 1.54 34.21 0.30 11.27 0.29 99.37MOX-25-120.6A Ilmenite Low-Cr 9 Core 52.08 1.72 34.14 0.32 11.21 0.28 99.75MOX-25-120.6A Ilmenite Low-Cr 10 Core 51.93 1.48 34.62 0.33 10.84 0.18 99.37MOX-25-120.6A Ilmenite Low-Cr 11 Spongy 51.79 1.69 34.50 0.39 11.41 0.23 100.00MOX-25-120.6A Ilmenite Low-Cr 12 Spongy 51.87 1.57 34.24 0.32 11.40 0.20 99.60MOX-25-120.6A Ilmenite Low-Cr 13 Spongy 51.87 1.65 33.93 0.38 11.28 0.28 99.39MOX-25-120.6A Ilmenite Low-Cr 14 Spongy 51.86 1.64 33.90 0.33 11.29 0.28 99.31MOX-25-120.6A Ilmenite Low-Cr 15 Spongy 51.79 1.55 34.49 0.35 11.36 0.24 99.78MOX-24-24.2 Ilmenite Low-Cr 1 Rim 53.52 3.26 29.15 0.32 13.44 0.02 99.72MOX-24-24.2 Ilmenite Low-Cr 2 Rim 52.95 3.15 29.37 0.23 13.39 0.02 99.11MOX-24-24.2 Ilmenite Low-Cr 3 Rim 53.39 3.00 30.49 0.24 13.23 0.02 100.37MOX-24-24.2 Ilmenite Low-Cr 4 Rim 52.49 2.87 31.43 0.27 12.92 0.02 99.99MOX-24-24.2 Ilmenite Low-Cr 5 Rim 51.99 4.62 29.28 0.27 13.28 0.03 99.47MOX-24-24.2 Ilmenite Low-Cr 6 Core 52.62 2.77 30.93 0.29 12.74 0.01 99.36MOX-24-24.2 Ilmenite Low-Cr 7 Core 52.69 2.93 31.25 0.27 12.81 0.00 99.96MOX-24-24.2 Ilmenite Low-Cr 8 Core 52.43 2.84 31.06 0.24 12.61 0.04 99.22MOX-24-24.2 Ilmenite Low-Cr 9 Core 52.63 2.93 30.92 0.32 12.85 0.01 99.66MOX-24-24.2 Ilmenite Low-Cr 10 Core 52.42 2.80 31.23 0.22 12.55 0.02 99.25Empty cells indicate concentrations that were below minimum detection levelsAppendix B. Major Element Analyses of Megacrysts 102Sample Mineral Suite Point Point Area O (apfu) Si (apfu) Ti (apfu) Al (apfu) Cr (apfu) Fe (apfu) Mn (apfu) Mg (apfu) Ca (apfu) Nb (apfu) TotalMOX-24-206.97 Ilmenite Low-Cr 1 Rim 3.000 0.933 0.047 0.621 0.006 0.426 0.001 0.002 5.035MOX-24-206.97 Ilmenite Low-Cr 2 Rim 3.000 0.933 0.045 0.624 0.006 0.426 0.003 5.036MOX-24-206.97 Ilmenite Low-Cr 3 Rim 3.000 0.928 0.003 0.047 0.628 0.006 0.428 0.002 5.042MOX-24-206.97 Ilmenite Low-Cr 4 Rim 3.000 0.929 0.046 0.629 0.006 0.430 5.040MOX-24-206.97 Ilmenite Low-Cr 5 Rim 3.000 0.926 0.003 0.047 0.634 0.006 0.426 0.002 5.044MOX-24-206.97 Ilmenite Low-Cr 6 Core 3.000 0.927 0.004 0.046 0.626 0.006 0.434 0.002 5.045MOX-24-206.97 Ilmenite Low-Cr 7 Core 3.000 0.928 0.044 0.638 0.005 0.429 5.043MOX-24-206.97 Ilmenite Low-Cr 8 Core 3.000 0.932 0.003 0.045 0.627 0.007 0.426 5.039MOX-24-206.97 Ilmenite Low-Cr 9 Core 3.000 0.930 0.046 0.634 0.006 0.427 5.042MOX-24-206.97 Ilmenite Low-Cr 10 Core 3.000 0.933 0.003 0.044 0.623 0.006 0.431 5.039MOX-24-206.97 Ilmenite Low-Cr 11 Spongy 3.000 0.935 0.003 0.045 0.629 0.005 0.420 5.037MOX-24-206.97 Ilmenite Low-Cr 12 Spongy 3.000 0.933 0.044 0.633 0.006 0.421 0.002 5.038MOX-24-206.97 Ilmenite Low-Cr 13 Spongy 3.000 0.929 0.003 0.044 0.627 0.007 0.431 0.002 5.043MOX-24-206.97 Ilmenite Low-Cr 14 Spongy 3.000 0.932 0.003 0.046 0.626 0.006 0.429 5.040MOX-24-206.97 Ilmenite Low-Cr 15 Spongy 3.000 0.930 0.045 0.633 0.006 0.425 0.002 5.041MOX-24-209.7 Ilmenite Low-Cr 1 Rim 3.000 0.002 0.937 0.003 0.037 0.639 0.005 0.415 5.038MOX-24-209.7 Ilmenite Low-Cr 2 Rim 3.000 0.936 0.005 0.035 0.645 0.005 0.413 0.002 5.040MOX-24-209.7 Ilmenite Low-Cr 3 Rim 3.000 0.935 0.037 0.638 0.006 0.420 0.002 5.039MOX-24-209.7 Ilmenite Low-Cr 4 Rim 3.000 0.935 0.005 0.038 0.636 0.006 0.419 0.001 0.002 5.040MOX-24-209.7 Ilmenite Low-Cr 5 Rim 3.000 0.938 0.003 0.037 0.610 0.006 0.445 0.001 5.040MOX-24-209.7 Ilmenite Low-Cr 6 Core 3.000 0.936 0.037 0.635 0.005 0.425 0.002 5.041MOX-24-209.7 Ilmenite Low-Cr 7 Core 3.000 0.932 0.004 0.042 0.633 0.005 0.424 0.002 5.042MOX-24-209.7 Ilmenite Low-Cr 8 Core 3.000 0.935 0.003 0.039 0.641 0.006 0.414 0.002 5.040MOX-24-209.7 Ilmenite Low-Cr 9 Core 3.000 0.929 0.005 0.037 0.643 0.006 0.422 0.002 5.044MOX-24-209.7 Ilmenite Low-Cr 10 Core 3.000 0.935 0.003 0.036 0.642 0.003 0.418 0.002 5.040MOX-28-308 Ilmenite Low-Cr 1 Rim 3.000 0.930 0.004 0.053 0.609 0.005 0.436 5.036MOX-28-308 Ilmenite Low-Cr 2 Rim 3.000 0.002 0.926 0.003 0.056 0.621 0.006 0.428 5.041MOX-28-308 Ilmenite Low-Cr 3 Rim 3.000 0.926 0.056 0.618 0.004 0.432 0.002 5.039MOX-28-308 Ilmenite Low-Cr 4 Rim 3.000 0.929 0.003 0.054 0.608 0.005 0.437 0.001 0.002 5.039MOX-28-308 Ilmenite Low-Cr 5 Rim 3.000 0.002 0.927 0.004 0.054 0.609 0.006 0.436 0.003 5.039MOX-28-308 Ilmenite Low-Cr 6 Core 3.000 0.924 0.003 0.055 0.617 0.006 0.437 0.002 5.043MOX-28-308 Ilmenite Low-Cr 7 Core 3.000 0.927 0.003 0.053 0.615 0.006 0.436 0.001 0.002 5.043MOX-28-308 Ilmenite Low-Cr 8 Core 3.000 0.923 0.003 0.056 0.618 0.006 0.439 5.044MOX-28-308 Ilmenite Low-Cr 9 Core 3.000 0.921 0.003 0.058 0.620 0.006 0.435 0.002 5.044MOX-28-308 Ilmenite Low-Cr 10 Core 3.000 0.928 0.004 0.056 0.607 0.006 0.435 0.001 0.002 5.039MOX-28-308 Ilmenite Low-Cr 11 Spongy 3.000 0.927 0.003 0.055 0.612 0.005 0.438 5.040MOX-28-308 Ilmenite Low-Cr 12 Spongy 3.000 0.928 0.004 0.054 0.610 0.005 0.436 5.038MOX-28-308 Ilmenite Low-Cr 13 Spongy 3.000 0.931 0.056 0.616 0.005 0.427 5.035MOX-28-308 Ilmenite Low-Cr 14 Spongy 3.000 0.925 0.004 0.052 0.619 0.006 0.436 5.042MOX-28-308 Ilmenite Low-Cr 15 Spongy 3.000 0.929 0.005 0.054 0.606 0.006 0.437 5.037MOX-3-74.4 Ilmenite Low-Cr 1 Rim 3.000 0.932 0.040 0.632 0.006 0.431 5.040MOX-3-74.4 Ilmenite Low-Cr 2 Rim 3.000 0.928 0.002 0.043 0.636 0.007 0.429 5.045MOX-3-74.4 Ilmenite Low-Cr 3 Rim 3.000 0.930 0.003 0.043 0.635 0.007 0.424 0.001 0.002 5.044MOX-3-74.4 Ilmenite Low-Cr 4 Rim 3.000 0.928 0.003 0.042 0.630 0.007 0.433 5.042MOX-3-74.4 Ilmenite Low-Cr 5 Rim 3.000 0.001 0.928 0.042 0.638 0.005 0.430 5.043MOX-3-74.4 Ilmenite Low-Cr 6 Core 3.000 0.936 0.004 0.041 0.626 0.007 0.425 5.038MOX-3-74.4 Ilmenite Low-Cr 7 Core 3.000 0.938 0.040 0.628 0.006 0.424 5.035MOX-3-74.4 Ilmenite Low-Cr 8 Core 3.000 0.935 0.004 0.043 0.624 0.007 0.422 0.000 0.002 5.037MOX-3-74.4 Ilmenite Low-Cr 9 Core 3.000 0.931 0.005 0.045 0.625 0.007 0.425 0.000 0.002 5.040MOX-3-74.4 Ilmenite Low-Cr 10 Core 3.000 0.932 0.044 0.632 0.007 0.423 5.038MOX-3-74.4 Ilmenite Low-Cr 11 Spongy 3.000 0.931 0.040 0.633 0.006 0.431 0.002 5.043MOX-3-74.4 Ilmenite Low-Cr 12 Spongy 3.000 0.937 0.004 0.041 0.625 0.005 0.421 0.002 5.034MOX-3-74.4 Ilmenite Low-Cr 13 Spongy 3.000 0.927 0.007 0.042 0.627 0.006 0.434 0.002 5.045MOX-3-74.4 Ilmenite Low-Cr 14 Spongy 3.000 0.927 0.044 0.610 0.006 0.452 0.002 0.002 5.043MOX-3-74.4 Ilmenite Low-Cr 15 Spongy 3.000 0.928 0.005 0.041 0.631 0.007 0.429 0.002 5.043Cation amounts for respective microprobe measurements. Empty cells indicate concentrations that were below minimum detection levelsAppendix B. Major Element Analyses of Megacrysts 103Sample Mineral Suite Point Point Area O (apfu) Si (apfu) Ti (apfu) Al (apfu) Cr (apfu) Fe (apfu) Mn (apfu) Mg (apfu) Ca (apfu) Nb (apfu) TotalMOX-25-65.16 Ilmenite Low-Cr 1 Rim 3.000 0.927 0.031 0.681 0.006 0.403 0.003 5.051MOX-25-65.16 Ilmenite Low-Cr 2 Rim 3.000 0.931 0.032 0.647 0.007 0.428 0.003 5.048MOX-25-65.16 Ilmenite Low-Cr 3 Rim 3.000 0.928 0.032 0.673 0.007 0.408 0.004 5.051MOX-25-65.16 Ilmenite Low-Cr 4 Rim 3.000 0.928 0.032 0.688 0.007 0.398 0.002 5.053MOX-25-65.16 Ilmenite Low-Cr 5 Rim 3.000 0.925 0.034 0.689 0.008 0.391 0.003 5.050MOX-25-65.16 Ilmenite Low-Cr 6 Core 3.000 0.925 0.033 0.692 0.006 0.396 0.002 5.054MOX-25-65.16 Ilmenite Low-Cr 7 Core 3.000 0.925 0.032 0.692 0.007 0.396 0.002 5.054MOX-25-65.16 Ilmenite Low-Cr 8 Core 3.000 0.926 0.030 0.691 0.006 0.399 0.001 0.002 5.056MOX-25-65.16 Ilmenite Low-Cr 9 Core 3.000 0.930 0.030 0.683 0.007 0.401 0.002 5.052MOX-25-65.16 Ilmenite Low-Cr 10 Core 3.000 0.926 0.031 0.693 0.007 0.394 0.003 5.053MOX-25-65.16 Ilmenite Low-Cr 11 Zoning 3.000 0.924 0.031 0.693 0.006 0.399 0.002 5.056MOX-25-65.16 Ilmenite Low-Cr 12 Zoning 3.000 0.927 0.032 0.686 0.006 0.400 0.002 5.053MOX-25-65.16 Ilmenite Low-Cr 13 Zoning 3.000 0.924 0.032 0.695 0.006 0.398 0.002 5.056MOX-25-65.16 Ilmenite Low-Cr 14 Zoning 3.000 0.927 0.031 0.686 0.007 0.401 0.002 5.053MOX-25-65.16 Ilmenite Low-Cr 15 Zoning 3.000 0.923 0.030 0.693 0.008 0.400 0.003 5.057MOX-24-206.73 Ilmenite Low-Cr 1 Rim 3.000 0.926 0.030 0.678 0.007 0.411 5.053MOX-24-206.73 Ilmenite Low-Cr 2 Rim 3.000 0.926 0.031 0.649 0.006 0.440 0.003 5.054MOX-24-206.73 Ilmenite Low-Cr 3 Rim 3.000 0.933 0.027 0.642 0.006 0.438 0.002 5.049MOX-24-206.73 Ilmenite Low-Cr 4 Rim 3.000 0.932 0.028 0.682 0.006 0.399 0.002 0.002 5.050MOX-24-206.73 Ilmenite Low-Cr 5 Rim 3.000 0.933 0.030 0.680 0.005 0.400 5.047MOX-24-206.73 Ilmenite Low-Cr 6 Core 3.000 0.925 0.031 0.692 0.007 0.398 0.003 5.054MOX-24-206.73 Ilmenite Low-Cr 7 Core 3.000 0.931 0.032 0.677 0.008 0.401 0.002 5.050MOX-24-206.73 Ilmenite Low-Cr 8 Core 3.000 0.930 0.030 0.683 0.006 0.401 0.002 5.052MOX-24-206.73 Ilmenite Low-Cr 9 Core 3.000 0.927 0.031 0.684 0.006 0.403 5.052MOX-24-206.73 Ilmenite Low-Cr 10 Core 3.000 0.929 0.031 0.686 0.007 0.394 0.003 5.049MOX-25-120.6A Ilmenite Low-Cr 1 Rim 3.000 0.926 0.031 0.680 0.007 0.406 0.002 5.054MOX-25-120.6A Ilmenite Low-Cr 2 Rim 3.000 0.924 0.033 0.682 0.007 0.407 0.003 5.055MOX-25-120.6A Ilmenite Low-Cr 3 Rim 3.000 0.940 0.031 0.668 0.006 0.395 0.002 5.042MOX-25-120.6A Ilmenite Low-Cr 4 Rim 3.000 0.937 0.031 0.677 0.008 0.390 0.003 5.044MOX-25-120.6A Ilmenite Low-Cr 5 Rim 3.000 0.929 0.031 0.684 0.006 0.398 0.003 5.050MOX-25-120.6A Ilmenite Low-Cr 6 Zoning 3.000 0.929 0.032 0.678 0.007 0.402 0.003 5.051MOX-25-120.6A Ilmenite Low-Cr 7 Core 3.000 0.930 0.029 0.688 0.006 0.395 0.003 5.050MOX-25-120.6A Ilmenite Low-Cr 8 Core 3.000 0.929 0.029 0.682 0.006 0.401 0.003 5.050MOX-25-120.6A Ilmenite Low-Cr 9 Core 3.000 0.931 0.032 0.679 0.006 0.397 0.003 5.048MOX-25-120.6A Ilmenite Low-Cr 10 Core 3.000 0.933 0.028 0.692 0.007 0.386 0.002 5.048MOX-25-120.6A Ilmenite Low-Cr 11 Spongy 3.000 0.925 0.032 0.685 0.008 0.404 0.003 5.056MOX-25-120.6A Ilmenite Low-Cr 12 Spongy 3.000 0.928 0.030 0.681 0.006 0.405 0.002 5.052MOX-25-120.6A Ilmenite Low-Cr 13 Spongy 3.000 0.930 0.031 0.676 0.008 0.401 0.003 5.048MOX-25-120.6A Ilmenite Low-Cr 14 Spongy 3.000 0.930 0.031 0.676 0.007 0.401 0.003 5.048MOX-25-120.6A Ilmenite Low-Cr 15 Spongy 3.000 0.927 0.029 0.686 0.007 0.403 0.003 5.055MOX-24-24.2 Ilmenite Low-Cr 1 Rim 3.000 0.933 0.060 0.565 0.006 0.465 2.029MOX-24-24.2 Ilmenite Low-Cr 2 Rim 3.000 0.929 0.058 0.573 0.005 0.466 2.030MOX-24-24.2 Ilmenite Low-Cr 3 Rim 3.000 0.929 0.055 0.590 0.005 0.456 2.036MOX-24-24.2 Ilmenite Low-Cr 4 Rim 3.000 0.921 0.053 0.614 0.005 0.449 2.042MOX-24-24.2 Ilmenite Low-Cr 5 Rim 3.000 0.913 0.085 0.572 0.005 0.462 2.037MOX-24-24.2 Ilmenite Low-Cr 6 Core 3.000 0.928 0.051 0.607 0.006 0.446 2.038MOX-24-24.2 Ilmenite Low-Cr 7 Core 3.000 0.924 0.054 0.609 0.005 0.445 2.038MOX-24-24.2 Ilmenite Low-Cr 8 Core 3.000 0.928 0.053 0.611 0.005 0.442 2.039MOX-24-24.2 Ilmenite Low-Cr 9 Core 3.000 0.926 0.054 0.605 0.006 0.448 2.039MOX-24-24.2 Ilmenite Low-Cr 10 Core 3.000 0.927 0.052 0.614 0.004 0.440 2.037Cation amounts for respective microprobe measurements. Empty cells indicate concentrations that were below minimum detection levelsAppendix B. Major Element Analyses of Megacrysts 104Sample MOX-24-124.0A MOX-24-124.0A MOX-24-124.0A MOX-24-124.0A MOX-24-209.7 MOX-24-209.7 MOX-24-209.7 MOX-24-209.7 MOX-28-320.1 MOX-28-320.1 MOX-28-320.1 MOX-28-320.1 MOX-28-320.1Suite High-Cr High-Cr High-Cr High-Cr Low-Cr Low-Cr Low-Cr Low-Cr High-Cr High-Cr High-Cr High-Cr High-CrSpot 1 2 3 4 1 2 3 4 1 2 3 4 5Li (ppm) 0.71 0.59 0.71 0.58 0.46 0.33 0.48 0.52 0.81 1.11 0.36 0.88 0.57Li 2SE 0.066 0.067 0.082 0.068 0.048 0.071 0.062 0.068 0.073 0.071 0.074 0.072 0.069Na (ppm) 18920 19630 22240 18620 15410 15330 15060 15160 18660 18500 18640 18590 18560Na 2SE 260 330 300 210 360 500 280 350 220 270 220 220 230Al (ppm) 15650 16040 17380 14740 12710 12710 12780 12660 15580 15670 15720 15420 15400Al 2SE 220 270 200 160 210 220 160 210 180 190 200 190 140Si (ppm) 355700 361900 370800 350000 371200 366200 359200 368700 358600 356500 354600 358000 357100Si 2SE 6200 6400 4500 3300 7800 9400 7900 9600 4600 4600 3600 5000 4500K (ppm) 375 377 397 384 249 238 253 244 342 345 348 340 339K 2SE 5.8 7.7 6.6 9.3 5.9 5.1 4.7 7.0 4.3 5.4 3.9 4.5 4.8Sc (ppm) 41.2 42.2 43.5 40.1 54.1 54.4 52.9 53.3 46.5 47.3 46.9 46.6 46.8Sc 2SE 0.69 0.93 0.64 0.63 1.0 1.1 0.95 0.98 0.75 0.78 0.71 0.61 0.69Ti (ppm) 2107 2257 2472 2155 1561 1566 1563 1552 2161 2177 2170 2165 2150Ti 2SE 27 38 26 18 23 22 21 23 22 26 23 27 25V (ppm) 509 504 506 497 499 498 492 502 523 524 523 520 525V 2SE 8.3 9.1 5.5 6.1 10 12 9.7 13 7 7.2 6.6 6.7 7.7Ni (ppm) 361 381 412 333 229 227 233 221 275 273 274 275 273Ni 2SE 5 6.2 5.3 5 7.2 6.5 6 6.4 3.8 4.7 3.9 4.1 4.3Rb (ppm) 0.00 0.02 0.10 0.07 0.01 0.05 0.04 0.01 0.01 0.00Rb 2SE 0.00 0.01 0.03 0.03 0.01 0.02 0.02 0.01 0.01 0.01Sr (ppm) 184 176 188 178 187 187 188 189 173 175 174 173 175Sr 2SE 2.20 2.50 2.10 2.10 3.80 3.20 3.40 3.20 1.90 2.60 2.10 2.00 2.00Y (ppm) 2.48 2.62 3.53 2.19 2.23 2.29 2.22 2.27 2.31 2.29 2.29 2.34 2.29Y 2SE 0.07 0.10 0.08 0.06 0.08 0.09 0.06 0.07 0.07 0.07 0.07 0.07 0.08Zr (ppm) 11.9 13.2 16.3 12.4 15.7 15.4 15.7 15.4 13.4 13.4 13.3 13.3 13.2Zr 2SE 0.21 0.35 0.34 0.26 0.31 0.39 0.36 0.34 0.24 0.31 0.29 0.30 0.27Nb (ppm) 0.33 0.38 0.50 0.34 0.27 0.28 0.43 0.33 0.30 0.37 0.31 0.31 0.31Nb 2SE 0.02 0.04 0.04 0.03 0.03 0.03 0.04 0.02 0.03 0.03 0.03 0.02 0.03Ba (ppm) 0.24 1.08 2.69 0.73 0.61 0.24 3.12 0.88 0.28 2.27 0.32 0.19 0.20Ba 2SE 0.08 0.22 0.83 0.14 0.15 0.11 0.56 0.26 0.09 0.42 0.11 0.06 0.08La (ppm) 2.96 2.84 3.21 2.69 2.68 2.61 2.78 2.68 2.67 2.86 2.73 2.66 2.66La 2SE 0.08 0.09 0.08 0.07 0.08 0.09 0.07 0.07 0.06 0.08 0.06 0.06 0.07Ce (ppm) 10.4 9.7 11.1 9.4 10.4 10.3 10.3 10.5 9.6 9.7 9.7 9.5 9.8Ce 2SE 0.17 0.19 0.22 0.16 0.21 0.28 0.22 0.27 0.15 0.18 0.18 0.14 0.17Pr (ppm) 1.71 1.53 1.82 1.53 1.68 1.63 1.61 1.64 1.51 1.56 1.55 1.52 1.55Pr 2SE 0.043 0.067 0.053 0.044 0.054 0.064 0.035 0.063 0.055 0.057 0.052 0.047 0.051Nd (ppm) 8.30 7.98 9.31 7.57 7.97 8.02 7.98 7.85 7.50 7.50 7.64 7.64 7.65Nd 2SE 0.28 0.32 0.29 0.24 0.26 0.35 0.31 0.29 0.26 0.30 0.30 0.27 0.27Sm (ppm) 1.82 1.70 2.25 1.60 1.74 1.89 1.86 1.85 1.58 1.62 1.68 1.72 1.73Sm 2SE 0.13 0.16 0.14 0.13 0.14 0.14 0.13 0.14 0.14 0.17 0.12 0.15 0.13Eu (ppm) 0.53 0.56 0.64 0.47 0.57 0.56 0.50 0.52 0.46 0.53 0.49 0.51 0.45Eu 2SE 0.037 0.045 0.042 0.027 0.049 0.052 0.041 0.030 0.034 0.050 0.033 0.040 0.030Gd (ppm) 1.35 1.41 1.83 1.18 1.38 1.29 1.30 1.27 1.26 1.28 1.33 1.33 1.29Gd 2SE 0.11 0.16 0.12 0.10 0.14 0.11 0.11 0.10 0.11 0.13 0.11 0.10 0.10Tb (ppm) 0.157 0.162 0.208 0.145 0.156 0.152 0.159 0.158 0.151 0.151 0.150 0.153 0.148Tb 2SE 0.01 0.02 0.01 0.02 0.01 0.02 0.02 0.01 0.02 0.02 0.02 0.01 0.02Dy (ppm) 0.79 0.66 1.10 0.67 0.76 0.72 0.67 0.75 0.65 0.71 0.70 0.67 0.72Dy 2SE 0.07 0.09 0.08 0.05 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07 0.07Ho (ppm) 0.11 0.12 0.15 0.10 0.10 0.10 0.11 0.11 0.10 0.10 0.10 0.10 0.10Ho 2SE 0.01 0.02 0.01 0.01 0.01 0.02 0.02 0.01 0.01 0.01 0.01 0.01 0.01Er (ppm) 0.21 0.26 0.33 0.20 0.21 0.20 0.19 0.21 0.20 0.19 0.20 0.19 0.22Er 2SE 0.03 0.04 0.04 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03Tm (ppm) 0.026 0.025 0.029 0.020 0.019 0.012 0.020 0.015 0.021 0.020 0.017 0.019 0.017Tm 2SE 0.005 0.007 0.007 0.005 0.005 0.005 0.005 0.004 0.006 0.005 0.006 0.005 0.005Yb (ppm) 0.11 0.15 0.13 0.10 0.09 0.07 0.09 0.11 0.09 0.09 0.11 0.10 0.10Yb 2SE 0.03 0.03 0.03 0.02 0.03 0.02 0.02 0.03 0.03 0.03 0.02 0.02 0.02Lu (ppm) 0.015 0.015 0.018 0.010 0.009 0.006 0.016 0.008 0.013 0.007 0.011 0.012 0.012Lu 2SE 0.004 0.005 0.005 0.003 0.004 0.004 0.005 0.003 0.005 0.003 0.003 0.003 0.004Hf (ppm) 0.92 0.92 1.30 0.91 1.09 1.13 1.11 1.02 0.96 1.00 1.00 0.93 0.86Hf 2SE 0.079 0.100 0.083 0.065 0.120 0.094 0.091 0.076 0.110 0.085 0.068 0.070 0.073Ta (ppm) 0.025 0.028 0.038 0.025 0.027 0.025 0.033 0.029 0.027 0.029 0.032 0.022 0.028Ta 2SE 0.006 0.008 0.006 0.005 0.005 0.006 0.008 0.006 0.006 0.006 0.007 0.005 0.007Pb (ppm) 0.44 0.44 0.45 0.43 0.44 0.43 0.43 0.43 0.47 0.49 0.51 0.47 0.46Pb 2SE 0.017 0.037 0.019 0.022 0.023 0.023 0.020 0.020 0.022 0.031 0.021 0.021 0.025Appendix C: Trace Element Analyses of ClinopyroxenesValues below 0.01 are reported as 0.00. Blank cells indicate measurements where the error exceeded the measured concentration105Sample MUSK-3-202.4 MUSK-3-202.4 MUSK-3-202.4 MUSK-3-202.4 MOX-24-34.3 MOX-24-34.3 MOX-24-34.3 MOX-24-34.3 MOX-24-34.3 MOX-1-43.35 MOX-1-43.35 MOX-1-43.35 MOX-1-43.35 MOX-1-43.35Suite High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr Low-Cr Low-Cr Low-Cr Low-Cr Low-CrSpot 1 2 3 4 1 2 3 4 5 1 2 3 4 5Li (ppm) 0.49 0.62 0.7 0.49 0.82 0.85 0.55 1.14 0.78 0.47 0.33 0.46 0.7 0.32Li 2SE 0.066 0.069 0.063 0.069 0.068 0.068 0.092 0.078 0.06 0.062 0.056 0.051 0.066Na (ppm) 18110 18030 18930 17810 18410 18590 18480 18590 18390 16120 15540 15490 16000 15630Na 2SE 270 250 210 370 340 350 330 260 310 390 370 330 280 410Al (ppm) 14330 14420 15230 14350 14250 14540 14160 14600 14170 12750 12540 12470 12850 12650Al 2SE 180 180 150 180 190 210 210 170 180 150 150 140 150 180Si (ppm) 358400 352400 353500 354500 352500 349100 354500 352400 352300 369900 361200 359500 361400 367000Si 2SE 4500 4900 3600 4900 4000 4400 6600 4100 4300 6000 5600 6200 5800 10000K (ppm) 314 336 385 387 365 357 352 360 364 275 260 266 269 267K 2SE 4.7 5.8 9.0 7.6 5.8 5.8 7.0 7.0 5.6 8.2 4.5 6.1 6.5 9.3Sc (ppm) 42.9 42.3 43.3 41.8 38.3 38.2 38.1 39.0 37.5 55.9 55.5 55.3 56.2 55.8Sc 2SE 0.67 0.59 0.59 0.59 0.66 0.68 0.76 0.67 0.59 0.91 0.6 0.79 0.8 0.94Ti (ppm) 2241 2219 2323 2106 1935 2072 1999 2074 1920 1666 1611 1593 1633 1589Ti 2SE 24 25 20 25 22 25 31 24 21 19 19 19 20 27V (ppm) 495 493 518 467 475 478 469 480 465 557 538 535 540 519V 2SE 6.1 8.1 5.4 6.8 5.1 6.3 8.4 7.5 7.3 14 10 9.2 9.6 14Ni (ppm) 323 321 325 317 363 367 367 367 369 200 198 194 201 199Ni 2SE 5.4 5.2 4.2 6.6 6.1 7 7.9 7.4 6.1 4.7 4.5 4.1 4.4 5.6Rb (ppm) 0.00 0.03 0.11 0.02 0.02 0.00 0.00 0.00 0.01 0.00Rb 2SE 0.01 0.01 0.04 0.01 0.01 0.01 0.01 0.01 0.01 0.00Sr (ppm) 161 165 166 176 170 168 166 170 171 202 199 199 199 195Sr 2SE 1.70 2.00 1.40 2.50 2.40 2.30 2.70 2.30 2.50 3.00 2.80 2.90 2.90 3.90Y (ppm) 2.66 2.55 2.58 2.49 2.05 2.24 2.17 2.21 2.03 2.10 2.02 2.03 2.12 2.09Y 2SE 0.07 0.07 0.06 0.07 0.07 0.07 0.07 0.07 0.06 0.07 0.05 0.06 0.06 0.07Zr (ppm) 12.5 12.2 12.8 11.6 9.5 11.3 10.7 11.3 9.8 15.3 15.0 15.0 15.5 15.1Zr 2SE 0.25 0.27 0.23 0.26 0.25 0.32 0.30 0.24 0.25 0.28 0.28 0.22 0.29 0.37Nb (ppm) 0.29 0.30 0.56 0.48 0.28 0.27 0.26 0.26 0.29 0.29 0.31 0.28 0.27 0.29Nb 2SE 0.02 0.02 0.04 0.04 0.03 0.02 0.03 0.03 0.02 0.02 0.02 0.02 0.02 0.03Ba (ppm) 0.26 0.50 3.34 5.37 0.27 0.28 0.29 0.27 0.32 0.27 0.23 0.30 0.30 0.26Ba 2SE 0.07 0.11 0.48 0.51 0.08 0.08 0.10 0.08 0.08 0.06 0.07 0.08 0.07 0.11La (ppm) 2.61 2.67 2.96 3.32 2.47 2.46 2.43 2.46 2.53 3.04 2.93 2.95 3.01 2.99La 2SE 0.05 0.05 0.07 0.09 0.07 0.07 0.07 0.07 0.07 0.06 0.07 0.07 0.07 0.10Ce (ppm) 9.5 9.6 10.0 10.9 8.9 8.8 9.0 8.8 9.0 11.6 11.2 11.2 11.5 11.3Ce 2SE 0.15 0.16 0.15 0.16 0.16 0.17 0.21 0.13 0.18 0.20 0.22 0.19 0.25 0.32Pr (ppm) 1.62 1.59 1.59 1.70 1.40 1.41 1.45 1.42 1.36 1.78 1.76 1.77 1.81 1.75Pr 2SE 0.046 0.048 0.049 0.051 0.052 0.044 0.053 0.044 0.039 0.052 0.044 0.049 0.048 0.066Nd (ppm) 7.9 7.7 7.9 7.9 7.0 7.1 6.9 6.8 6.8 8.7 8.4 8.5 8.8 8.5Nd 2SE 0.27 0.23 0.28 0.24 0.29 0.29 0.24 0.28 0.22 0.28 0.28 0.24 0.24 0.32Sm (ppm) 1.80 1.81 1.67 1.82 1.56 1.66 1.53 1.49 1.39 1.80 1.80 1.72 1.73 1.77Sm 2SE 0.11 0.14 0.14 0.12 0.11 0.13 0.13 0.12 0.11 0.12 0.11 0.12 0.10 0.15Eu (ppm) 0.50 0.50 0.52 0.49 0.42 0.47 0.46 0.47 0.43 0.52 0.49 0.52 0.52 0.52Eu 2SE 0.034 0.035 0.034 0.037 0.035 0.031 0.039 0.040 0.034 0.028 0.032 0.031 0.033 0.038Gd (ppm) 1.28 1.34 1.33 1.30 1.04 1.25 1.20 1.28 1.15 1.20 1.21 1.30 1.41 1.29Gd 2SE 0.10 0.10 0.10 0.09 0.10 0.09 0.11 0.12 0.10 0.09 0.08 0.11 0.11 0.13Tb (ppm) 0.174 0.154 0.160 0.150 0.118 0.139 0.131 0.135 0.133 0.148 0.149 0.142 0.151 0.129Tb 2SE 0.01 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.01Dy (ppm) 0.80 0.83 0.75 0.84 0.63 0.65 0.69 0.68 0.65 0.60 0.58 0.66 0.69 0.64Dy 2SE 0.07 0.07 0.07 0.07 0.06 0.07 0.06 0.06 0.06 0.06 0.05 0.05 0.06 0.07Ho (ppm) 0.13 0.11 0.11 0.12 0.10 0.10 0.10 0.11 0.09 0.10 0.09 0.09 0.09 0.09Ho 2SE 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Er (ppm) 0.21 0.22 0.20 0.21 0.19 0.19 0.20 0.19 0.16 0.16 0.18 0.19 0.17 0.20Er 2SE 0.02 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.03 0.02 0.03 0.02 0.03 0.03Tm (ppm) 0.022 0.019 0.021 0.023 0.015 0.020 0.019 0.018 0.017 0.016 0.015 0.019 0.014 0.014Tm 2SE 0.005 0.005 0.005 0.006 0.005 0.005 0.005 0.005 0.004 0.004 0.004 0.004 0.005 0.005Yb (ppm) 0.14 0.11 0.10 0.08 0.09 0.07 0.07 0.08 0.09 0.10 0.09 0.07 0.09 0.06Yb 2SE 0.03 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02Lu (ppm) 0.008 0.015 0.016 0.015 0.008 0.008 0.009 0.012 0.008 0.008 0.008 0.011 0.007 0.011Lu 2SE 0.003 0.004 0.005 0.006 0.003 0.003 0.003 0.004 0.003 0.003 0.003 0.003 0.003 0.005Hf (ppm) 0.92 0.93 1.00 0.84 0.73 0.74 0.73 0.76 0.65 1.05 0.99 1.04 1.03 0.95Hf 2SE 0.068 0.072 0.085 0.072 0.078 0.064 0.070 0.069 0.061 0.056 0.069 0.066 0.074 0.100Ta (ppm) 0.02 0.03 0.03 0.03 0.02 0.02 0.02 0.02 0.02 0.03 0.02 0.03 0.03 0.02Ta 2SE 0.004 0.006 0.007 0.006 0.005 0.005 0.005 0.006 0.006 0.005 0.005 0.004 0.006 0.007Pb (ppm) 0.38 0.41 0.43 0.49 0.43 0.42 0.42 0.42 0.42 0.50 0.48 0.50 0.50 0.49Pb 2SE 0.020 0.018 0.022 0.028 0.020 0.021 0.025 0.023 0.024 0.024 0.023 0.022 0.023 0.027Values below 0.01 are reported as 0.00. Blank cells indicate measurements where the error exceeded the measured concentrationAppendix C: Trace Element Analyses of Clinopyroxenes106Sample MUSK-3-158.8 MUSK-3-158.8 MUSK-3-158.8 MUSK-3-158.8 MUSK-3-158.8 MUSK-3-198.37 MUSK-3-198.37 MUSK-3-198.37 MUSK-3-198.37 MUSK-3-198.37 MOX-25-161.5C MOX-25-161.5C MOX-25-161.5C MOX-25-161.5C MOX-25-161.5CSuite High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-Cr High-CrSpot 1 2 3 4 5 1 2 3 4 5 1 2 3 4 5Li (ppm) 0.64 0.59 0.67 0.46 0.74 0.58 0.59 0.90 0.68 1.00 0.96 1.04 0.62 1.38 0.79Li 2SE 0.051 0.047 0.064 0.07 0.058 0.064 0.076 0.051 0.061 0.096 0.082 0.087 0.064 0.082 0.08Na (ppm) 17270 17510 17940 17110 18110 19470 19960 19460 19710 19900 20960 20490 18520 20170 21770Na 2SE 260 260 290 340 280 460 530 520 530 1100 290 370 370 380 380Al (ppm) 15340 15430 15910 15330 15940 14860 14810 14940 14760 14310 16940 16500 14410 16270 17220Al 2SE 160 180 160 200 190 200 200 190 190 360 210 200 220 240 240Si (ppm) 351300 358500 360800 354700 363000 373600 379300 366800 373300 383000 365000 361100 342500 353400 371600Si 2SE 4200 4200 4500 5500 4400 8700 8600 5700 7300 14000 4500 5300 6400 5500 6600K (ppm) 301 300 311 300 312 348 359 339 341 344 334 331 374 393 340K 2SE 4.8 4.6 4.8 5.4 5.5 8.2 11 6.6 8.1 13 5.5 6.1 7.1 5.4 6.4Sc (ppm) 47.2 46.7 48.0 47.5 47.3 42.9 43.2 43.1 42.2 42.6 41.8 41.1 38.4 40.1 40.9Sc 2SE 0.69 0.63 0.66 0.71 0.7 0.57 0.65 0.58 0.65 1.2 0.73 0.77 0.86 0.7 0.81Ti (ppm) 1982 1982 2033 1999 2011 2097 2113 2122 2103 2091 2495 2512 2060 2306 2625Ti 2SE 17 18 21 25 20 26 27 25 25 53 28 35 38 32 33V (ppm) 485 493 504 468 508 525 526 523 511 507 484 473 464 477 480V 2SE 6 7.3 5.5 5.2 5.7 13 11 10 13 21 6.4 7.4 7.6 7 6.9Ni (ppm) 246 251 252 244 252 321 315 313 312 317 411 413 334 373 430Ni 2SE 4.4 4.5 3.8 5.4 4.1 8.3 7.4 6.7 8.7 14 7.6 7.6 7.6 5.9 7.7Rb (ppm) 0.00 0.00 0.00 0.00 0.00 0.01 0.01 0.02 0.00 0.02 0.01 0.01 0.02 0.01 0.00Rb 2SE 0.00 0.00 0.01 0.00 0.00 0.01 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.00Sr (ppm) 188 186 191 191 189 179 181 179 178 176 181 181 169 174 178Sr 2SE 2.00 1.90 2.20 3.00 1.90 2.80 2.90 3.00 2.40 5.30 2.70 2.60 3.00 2.90 2.10Y (ppm) 2.49 2.52 2.47 2.39 2.37 2.43 2.47 2.48 2.49 2.43 3.54 3.41 2.05 2.43 3.44Y 2SE 0.07 0.08 0.06 0.06 0.07 0.06 0.07 0.06 0.07 0.10 0.09 0.08 0.08 0.08 0.10Zr (ppm) 14.8 14.6 15.2 14.5 14.9 13.9 14.3 14.2 14.1 13.6 16.8 16.8 11.5 12.7 16.9Zr 2SE 0.25 0.35 0.25 0.31 0.26 0.24 0.26 0.27 0.28 0.43 0.33 0.39 0.29 0.33 0.36Nb (ppm) 0.290 0.278 0.305 0.312 0.294 0.297 0.283 0.309 0.302 0.328 0.343 0.328 0.337 0.457 0.350Nb 2SE 0.02 0.02 0.03 0.03 0.02 0.02 0.02 0.02 0.03 0.05 0.03 0.03 0.03 0.04 0.03Ba (ppm) 0.37 0.28 0.20 0.22 0.20 0.30 0.34 0.36 0.52 0.82 0.19 0.28 1.01 2.07 0.27Ba 2SE 0.09 0.08 0.06 0.08 0.06 0.06 0.06 0.08 0.12 0.19 0.07 0.09 0.21 0.29 0.09La (ppm) 2.90 2.93 2.94 2.97 2.89 2.74 2.75 2.80 2.76 2.77 2.92 2.89 2.70 2.80 2.86La 2SE 0.07 0.05 0.06 0.08 0.06 0.06 0.06 0.06 0.07 0.10 0.09 0.07 0.09 0.08 0.07Ce (ppm) 10.4 10.6 10.4 10.7 10.4 10.9 10.8 10.5 10.6 11.5 10.8 10.7 9.5 9.6 10.8Ce 2SE 0.16 0.16 0.15 0.17 0.16 0.22 0.23 0.19 0.22 0.39 0.20 0.18 0.21 0.21 0.20Pr (ppm) 1.71 1.75 1.73 1.76 1.66 1.66 1.71 1.69 1.65 1.74 1.78 1.78 1.47 1.49 1.73Pr 2SE 0.05 0.06 0.05 0.06 0.05 0.06 0.05 0.05 0.05 0.09 0.07 0.06 0.06 0.05 0.06Nd (ppm) 8.6 8.7 8.5 8.4 8.4 8.3 8.2 8.0 8.0 8.4 9.5 9.1 7.2 7.4 9.0Nd 2SE 0.25 0.25 0.25 0.33 0.23 0.28 0.27 0.23 0.25 0.43 0.33 0.32 0.34 0.28 0.30Sm (ppm) 1.9 1.9 2.0 2.0 2.0 1.8 1.9 1.8 1.8 1.8 2.2 2.2 1.5 1.6 2.2Sm 2SE 0.11 0.12 0.13 0.17 0.12 0.11 0.13 0.10 0.11 0.20 0.18 0.14 0.13 0.15 0.17Eu (ppm) 0.56 0.56 0.55 0.55 0.54 0.58 0.50 0.52 0.50 0.53 0.66 0.63 0.44 0.48 0.67Eu 2SE 0.04 0.03 0.03 0.04 0.03 0.03 0.03 0.04 0.03 0.05 0.05 0.05 0.05 0.04 0.04Gd (ppm) 1.4 1.4 1.4 1.4 1.4 1.3 1.3 1.4 1.3 1.3 1.8 1.7 1.2 1.4 1.8Gd 2SE 0.11 0.11 0.10 0.12 0.10 0.12 0.10 0.09 0.09 0.12 0.11 0.13 0.11 0.12 0.12Tb (ppm) 0.172 0.167 0.166 0.173 0.161 0.156 0.154 0.168 0.157 0.154 0.204 0.194 0.133 0.143 0.216Tb 2SE 0.01 0.01 0.01 0.02 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.02 0.01 0.02 0.02Dy (ppm) 0.80 0.82 0.77 0.76 0.74 0.71 0.76 0.73 0.71 0.74 1.07 0.96 0.61 0.78 1.02Dy 2SE 0.05 0.07 0.07 0.06 0.06 0.06 0.06 0.05 0.05 0.08 0.09 0.07 0.07 0.09 0.08Ho (ppm) 0.11 0.12 0.11 0.11 0.11 0.10 0.11 0.11 0.11 0.10 0.17 0.14 0.08 0.10 0.16Ho 2SE 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.01 0.01 0.02Er (ppm) 0.21 0.21 0.23 0.22 0.19 0.20 0.22 0.21 0.22 0.19 0.28 0.31 0.17 0.21 0.31Er 2SE 0.03 0.03 0.02 0.03 0.03 0.03 0.03 0.03 0.03 0.04 0.04 0.04 0.03 0.04 0.04Tm (ppm) 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.04 0.03 0.02 0.02 0.04Tm 2SE 0.005 0.005 0.005 0.006 0.004 0.005 0.005 0.004 0.005 0.006 0.007 0.006 0.005 0.006 0.008Yb (ppm) 0.08 0.09 0.12 0.13 0.08 0.10 0.11 0.10 0.09 0.12 0.15 0.11 0.08 0.13 0.14Yb 2SE 0.02 0.02 0.02 0.03 0.02 0.02 0.02 0.02 0.02 0.04 0.03 0.03 0.02 0.03 0.03Lu (ppm) 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.01 0.01 0.02Lu 2SE 0.004 0.004 0.003 0.004 0.004 0.003 0.004 0.003 0.003 0.004 0.005 0.006 0.004 0.005 0.005Hf (ppm) 1.04 1.04 1.04 1.10 1.08 0.97 0.94 0.96 0.95 0.93 1.18 1.10 0.72 0.94 1.15Hf 2SE 0.069 0.068 0.067 0.089 0.067 0.075 0.076 0.073 0.065 0.120 0.097 0.087 0.071 0.110 0.100Ta (ppm) 0.03 0.03 0.03 0.02 0.03 0.03 0.02 0.02 0.02 0.02 0.03 0.02 0.03 0.04 0.02Ta 2SE 0.006 0.005 0.005 0.005 0.005 0.005 0.004 0.004 0.005 0.007 0.006 0.006 0.006 0.009 0.005Pb (ppm) 0.43 0.44 0.45 0.46 0.47 0.43 0.42 0.44 0.43 0.47 0.40 0.40 0.41 0.44 0.40Pb 2SE 0.021 0.019 0.021 0.022 0.022 0.018 0.021 0.021 0.020 0.037 0.021 0.021 0.021 0.021 0.022Values below 0.01 are reported as 0.00. Blank cells indicate measurements where the error exceeded the measured concentrationAppendix C: Trace Element Analyses of Clinopyroxenes107Sample Type Primary Primary Primary Primary Primary Primary Primary Primary Primary Primary Primary Metasomatic Metasomatic MetasomaticSample MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-3-33.0 MOX-7-62.3 MOX-7-62.3 MOX-7-62.3Spot 1 2 3 4 5 6 7 8 9 10 11 1 2 3Li (ppm) 0.03 0.03 0.03 0.03 0.03 0.03 0.04 0.03 0.03 0.03 0.04 0.04 0.04 0.04Li 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.00Na (ppm) 747 661 588 782 635 627 739 693 670 764 680 510 542 500Na 2SE 29 25 21 41 15 18 43 31 29 33 25 11 18 10Al (ppm) 541 465 474 516 505 490 497 470 512 574 499 553 601 576Al 2SE 16 15 14 17 14 13 20 16 20 28 17 16 20 11Si (ppm) 15950 15990 15140 17820 15870 15540 16280 16050 15170 16900 15190 15300 15820 14410Si 2SE 570 660 500 980 380 400 820 930 770 590 570 400 370 240K (ppm) 1.9 5.8 0.4 0.9 0.5 0.6 4.3 3.0 2.7 0.5 10.2 12.4 19.1 7.2K 2SE 0.1 0.3 0.0 0.1 0.0 0.0 0.7 0.2 0.2 0.1 2.0 1.2 2.2 0.5Sc (ppm) 1.70 1.52 1.75 1.67 1.80 1.75 1.63 1.52 1.67 1.79 1.49 2.24 2.31 2.31Sc 2SE 0.05 0.05 0.05 0.06 0.05 0.05 0.08 0.06 0.06 0.08 0.05 0.05 0.06 0.03Ti (ppm) 9.8 9.3 9.4 9.7 9.9 9.5 9.4 9.2 9.3 10.0 9.5 5.2 5.4 6.0Ti 2SE 0.3 0.3 0.2 0.4 0.3 0.3 0.4 0.3 0.4 0.4 0.4 0.2 0.2 0.1V (ppm) 22.4 19.5 20.0 23.0 20.6 20.5 20.9 20.6 19.8 24.2 19.8 20.8 20.9 22.1V 2SE 0.83 0.69 0.52 1.10 0.53 0.64 0.91 0.88 1.20 1.20 0.65 0.54 0.45 0.35Ni (ppm) 19.4 19.0 17.3 20.8 18.3 18.4 19.9 19.3 18.1 19.7 18.3 17.3 18.0 16.6Ni 2SE 0.70 0.65 0.50 1.20 0.45 0.58 1.10 0.93 1.00 1.10 0.77 0.47 0.57 0.35Rb (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.03 0.01 0.01 0.00Rb 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00Sr (ppm) 74 74 72 87 77 75 78 78 79 82 74 9 10 7Sr 2SE 2.5 2.6 1.8 5.0 2.2 2.2 4.3 3.4 4.8 3.3 2.9 0.3 0.3 0.1Y (ppm) 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.03 0.02 0.02 0.03 0.02Y 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Zr (ppm) 0.29 0.14 0.14 0.28 0.15 0.16 0.25 0.20 0.23 0.33 0.18 0.06 0.06 0.07Zr 2SE 0.02 0.01 0.01 0.02 0.01 0.01 0.02 0.02 0.02 0.03 0.01 0.01 0.01 0.01Nb (ppm) 0.01 0.01 0.00 0.01 0.00 0.00 0.01 0.01 0.02 0.01 0.01 0.12 0.17 0.08Nb 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.01 0.02 0.01Ba (ppm) 0.02 0.09 0.02 0.03 0.02 0.02 2.55 0.16 0.28 0.02 0.03 0.20 0.29 0.12Ba 2SE 0.01 0.03 0.00 0.01 0.01 0.01 0.67 0.03 0.13 0.01 0.01 0.03 0.05 0.02La (ppm) 1.72 1.48 0.93 1.58 1.01 0.97 1.54 1.35 1.49 1.81 1.36 0.28 0.33 0.14La 2SE 0.05 0.04 0.03 0.05 0.03 0.03 0.06 0.05 0.05 0.07 0.04 0.01 0.01 0.00Ce (ppm) 5.3 5.0 3.3 5.4 3.5 3.4 5.1 4.5 4.7 5.4 4.5 0.7 0.8 0.3Ce 2SE 0.16 0.15 0.07 0.24 0.10 0.08 0.23 0.23 0.20 0.23 0.14 0.03 0.03 0.01Pr (ppm) 0.72 0.68 0.48 0.71 0.51 0.49 0.68 0.62 0.64 0.71 0.63 0.07 0.07 0.03Pr 2SE 0.02 0.02 0.02 0.03 0.01 0.01 0.03 0.02 0.03 0.03 0.02 0.00 0.00 0.00Nd (ppm) 2.69 2.50 1.99 2.66 2.10 2.03 2.53 2.37 2.43 2.73 2.41 0.19 0.23 0.11Nd 2SE 0.08 0.08 0.06 0.09 0.05 0.06 0.12 0.09 0.08 0.12 0.09 0.01 0.01 0.01Sm (ppm) 0.23 0.18 0.17 0.23 0.18 0.18 0.21 0.18 0.21 0.26 0.18 0.02 0.03 0.02Sm 2SE 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.01 0.00 0.00 0.00Eu (ppm) 0.04 0.03 0.03 0.04 0.03 0.03 0.04 0.04 0.04 0.05 0.03 0.01 0.01 0.01Eu 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Gd (ppm) 0.07 0.04 0.04 0.05 0.04 0.04 0.05 0.05 0.04 0.07 0.04 0.01 0.01 0.01Gd 2SE 0.01 0.00 0.00 0.01 0.01 0.01 0.01 0.00 0.01 0.01 0.01 0.00 0.00 0.00Tb (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Tb 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Dy (ppm) 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.00 0.00 0.00Dy 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Ho (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Ho 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Er (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Er 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Tm (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Tm 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Yb (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Yb 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Lu (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Lu 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Hf (ppm) 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.00 0.00 0.00Hf 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Ta (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Ta 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Pb (ppm) 0.37 0.49 0.35 0.39 0.37 0.37 0.39 0.42 0.40 0.40 0.41 0.09 0.10 0.06Pb 2SE 0.02 0.02 0.01 0.01 0.01 0.01 0.02 0.02 0.02 0.02 0.02 0.00 0.01 0.00Th (ppm) 0.05 0.02 0.01 0.05 0.02 0.01 0.05 0.04 0.04 0.06 0.03 0.01 0.01 0.00Th 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00U (ppm) 0.01 0.00 0.00 0.01 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.00U 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Values below 0.01 are reported as 0.00. Blank cells indicate measurements where the error exceeded the measured concentrationAppendix C: Trace Element Analyses of Clinopyroxenes108Sample Type Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite WebsteriteSample MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6 MOX-24-42.6Spot 1 2 3 4 5 6 7 8 9 10 11 12Li (ppm) 1.55 1.23 1.23 1.20 1.51 1.45 1.17 1.34 1.94 1.59 1.52 1.28Li 2SE 0.09 0.10 0.09 0.09 0.12 0.10 0.09 0.11 0.12 0.11 0.11 0.09Na (ppm) 19020 20660 22390 21010 19170 22180 22680 22810 18980 19390 20920 21140Na 2SE 260 410 350 350 460 340 380 330 330 290 390 420Al (ppm) 15980 15480 16860 15950 15180 17000 16980 17120 15970 16590 15660 15610Al 2SE 210 320 180 210 280 170 130 190 240 270 210 220Si (ppm) 355700 366900 363000 359300 349500 368500 360800 366300 346800 348000 360000 364800Si 2SE 5200 8300 5100 4700 5600 4400 5600 4500 5400 4700 5700 6000K (ppm) 931 585 488 897 967 1522 382 481 1953 1703 799 644K 2SE 40.0 20.0 9.2 34.0 36.0 92.0 7.8 12.0 59.0 64.0 40.0 14.0Sc (ppm) 42.4 35.4 40.6 38.3 38.0 40.8 40.3 40.6 42.0 41.7 37.6 37.1Sc 2SE 0.49 0.79 0.59 0.69 0.80 0.57 0.58 0.55 0.73 0.59 0.62 0.63Ti (ppm) 2016 2102 2365 2138 1923 2513 2470 2480 2157 2124 2157 2135Ti 2SE 25 42 23 27 31 31 22 29 27 33 26 31V (ppm) 512 462 459 506 482 465 465 465 511 521 461 459V 2SE 7.3 11.0 5.9 9.1 8.6 5.1 5.9 5.1 8.3 7.5 6.9 7.3Ni (ppm) 443 475 471 490 450 481 477 476 409 450 502 496Ni 2SE 6.7 11.0 8.2 8.1 11.0 7.6 8.9 7.3 6.5 7.4 8.5 9.9Rb (ppm) 1.58 0.71 0.24 1.37 2.38 3.91 0.03 0.48 6.09 5.77 2.33 1.29Rb 2SE 0.13 0.09 0.04 0.15 0.24 0.45 0.02 0.10 0.34 0.35 0.26 0.12Sr (ppm) 171 193 199 191 203 221 199 200 225 192 194 205Sr 2SE 2.2 4.8 2.1 2.8 5.6 2.7 2.4 2.2 4.8 3.0 3.4 4.0Y (ppm) 2.60 2.83 3.41 2.75 2.47 3.67 3.50 3.48 2.82 2.65 2.98 2.97Y 2SE 0.06 0.07 0.08 0.07 0.07 0.08 0.06 0.08 0.07 0.07 0.08 0.11Zr (ppm) 13.6 11.7 16.7 15.3 12.4 18.6 17.2 16.7 14.7 14.5 12.6 12.5Zr 2SE 0.60 0.50 0.64 0.63 0.69 0.55 0.46 0.57 0.71 0.62 0.51 0.45Nb (ppm) 1.31 1.41 0.74 2.14 1.10 4.62 0.34 0.35 6.43 3.47 0.61 0.77Nb 2SE 0.04 0.05 0.04 0.17 0.05 0.14 0.03 0.03 0.16 0.18 0.06 0.06Ba (ppm) 19.0 17.8 5.9 19.7 165.0 51.4 0.4 2.3 285.0 74.0 34.6 109.0Ba 2SE 1.7 1.4 0.5 1.8 65.0 1.9 0.2 0.7 72.0 5.7 7.0 33.0La (ppm) 3.59 4.04 3.48 4.36 4.00 6.42 3.27 3.35 8.33 5.42 3.59 3.78La 2SE 0.09 0.11 0.08 0.14 0.13 0.10 0.08 0.13 0.24 0.16 0.08 0.10Ce (ppm) 10.5 12.5 11.3 12.5 10.8 16.5 11.5 11.4 17.8 13.6 11.3 11.5Ce 2SE 0.21 0.34 0.19 0.24 0.24 0.25 0.19 0.20 0.41 0.31 0.23 0.21Pr (ppm) 1.65 1.89 1.88 1.87 1.65 2.43 1.89 1.85 2.38 1.94 1.80 1.84Pr 2SE 0.05 0.08 0.06 0.08 0.07 0.07 0.05 0.06 0.07 0.07 0.06 0.06Nd (ppm) 8.31 9.42 9.83 9.31 8.09 11.76 9.97 9.79 10.63 9.43 9.26 9.47Nd 2SE 0.32 0.34 0.31 0.28 0.30 0.38 0.35 0.38 0.41 0.34 0.36 0.41Sm (ppm) 1.80 1.98 2.10 2.02 1.83 2.38 2.37 2.36 2.13 1.95 1.98 2.11Sm 2SE 0.16 0.15 0.16 0.20 0.15 0.20 0.17 0.13 0.16 0.16 0.18 0.17Eu (ppm) 0.51 0.57 0.66 0.54 0.50 0.70 0.64 0.61 0.63 0.54 0.57 0.63Eu 2SE 0.05 0.06 0.05 0.05 0.04 0.05 0.05 0.05 0.05 0.05 0.05 0.06Gd (ppm) 1.29 1.44 1.80 1.50 1.23 1.84 1.81 1.70 1.58 1.50 1.60 1.60Gd 2SE 0.10 0.13 0.16 0.14 0.10 0.18 0.13 0.14 0.12 0.13 0.14 0.12Tb (ppm) 0.16 0.18 0.21 0.18 0.17 0.24 0.22 0.20 0.17 0.16 0.18 0.18Tb 2SE 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02 0.02Dy (ppm) 0.84 0.82 0.96 0.81 0.65 1.01 1.13 1.04 0.78 0.82 0.87 0.95Dy 2SE 0.09 0.08 0.08 0.09 0.07 0.10 0.09 0.08 0.06 0.08 0.09 0.09Ho (ppm) 0.11 0.13 0.15 0.10 0.11 0.16 0.16 0.16 0.13 0.11 0.13 0.13Ho 2SE 0.02 0.02 0.02 0.01 0.01 0.02 0.02 0.02 0.02 0.01 0.02 0.02Er (ppm) 0.18 0.25 0.31 0.22 0.22 0.34 0.34 0.31 0.23 0.22 0.26 0.29Er 2SE 0.03 0.05 0.04 0.03 0.04 0.05 0.04 0.04 0.04 0.04 0.05 0.04Tm (ppm) 0.02 0.03 0.02 0.03 0.02 0.04 0.03 0.04 0.03 0.02 0.02 0.03Tm 2SE 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Yb (ppm) 0.09 0.13 0.15 0.12 0.08 0.16 0.16 0.15 0.10 0.09 0.10 0.09Yb 2SE 0.02 0.04 0.03 0.04 0.03 0.04 0.04 0.03 0.03 0.03 0.03 0.03Lu (ppm) 0.02 0.02 0.02 0.02 0.01 0.01 0.02 0.02 0.01 0.01 0.01 0.01Lu 2SE 0.01 0.01 0.01 0.01 0.00 0.01 0.01 0.01 0.01 0.00 0.01 0.01Hf (ppm) 0.85 0.80 0.99 0.94 0.78 1.11 1.17 1.06 0.86 0.90 0.89 0.90Hf 2SE 0.09 0.09 0.12 0.11 0.10 0.09 0.11 0.10 0.09 0.11 0.09 0.10Ta (ppm) 0.07 0.06 0.04 0.11 0.04 0.27 0.03 0.03 0.32 0.21 0.03 0.05Ta 2SE 0.01 0.01 0.01 0.01 0.01 0.02 0.01 0.01 0.02 0.03 0.01 0.01Pb (ppm) 1.95 0.64 0.52 1.00 3.43 0.74 0.45 0.54 3.23 2.07 0.62 0.56Pb 2SE 0.30 0.05 0.04 0.08 0.64 0.05 0.04 0.05 0.43 0.24 0.05 0.05Th (ppm) 0.14 0.14 0.08 0.21 0.12 0.46 0.04 0.04 0.71 0.33 0.05 0.07Th 2SE 0.01 0.01 0.01 0.02 0.01 0.02 0.01 0.01 0.03 0.03 0.01 0.01U (ppm) 0.03 0.03 0.01 0.04 0.04 0.08 0.01 0.01 0.10 0.05 0.02 0.02U 2SE 0.01 0.00 0.00 0.01 0.02 0.01 0.00 0.00 0.01 0.01 0.00 0.00Values below 0.01 are reported as 0.00. Blank cells indicate measurements where the error exceeded the measured concentrationAppendix C: Trace Element Analyses of Clinopyroxenes109Sample Type Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite Websterite WebsteriteSample MOX-7-30.02 MOX-7-30.02 MOX-7-30.02 MOX-7-30.02 MOX-7-30.02 MOX-7-30.02 MOX-7-30.02 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7 MOX-24-206.7Spot 1 2 3 4 5 6 7 1 2 3 4 5 6 7 8 9 10 11Li (ppm) 0.82 1.16 1.11 1.09 0.99 0.99 1.11 0.07 0.07 0.09 0.07 0.06 0.11 0.05 0.07 0.06 0.09 0.06Li 2SE 0.06 0.08 0.06 0.08 0.06 0.08 0.08 0.01 0.00 0.01 0.00 0.00 0.01 0.00 0.00 0.00 0.01 0.00Na (ppm) 19580 22380 24420 21610 23030 20740 24980 1016 994 939 960 997 1095 974 1129 1112 1014 1115Na 2SE 200 370 260 290 290 320 260 18 15 16 12 12 15 8 12 15 19 14Al (ppm) 13020 13190 15970 15410 15670 15590 17090 718 718 639 693 655 780 706 825 727 713 765Al 2SE 100 210 140 140 160 180 170 9 9 11 6 4 13 3 7 8 9 7Si (ppm) 316600 337000 330000 334500 325500 332800 352200 17090 16420 16710 16610 16190 17380 16690 18110 17750 16670 18040Si 2SE 2900 5800 3800 4600 3900 4200 3700 240 220 260 160 130 250 150 160 190 200 160K (ppm) 623 680 573 513 490 1316 958 48 37 56 52 43 86 27 50 40 65 39K 2SE 21.0 19.0 13.0 8.5 5.7 91.0 26.0 1.9 2.0 3.3 2.2 1.6 14.0 1.0 1.3 1.4 8.7 0.9Sc (ppm) 33.1 31.8 38.3 38.7 38.3 37.4 40.9 1.6 1.7 1.6 1.6 1.6 1.9 1.6 2.0 1.8 1.8 1.8Sc 2SE 0.39 0.53 0.32 0.65 0.56 0.54 0.53 0.03 0.02 0.03 0.02 0.02 0.03 0.02 0.03 0.02 0.03 0.03Ti (ppm) 2243 2221 2417 2249 2303 2570 2641 91 110 108 94 98 118 109 123 116 111 118Ti 2SE 18.0 35.0 22.0 22.0 23.0 28.0 27.0 1.1 1.3 1.8 0.8 0.7 3.1 0.7 1.4 1.0 1.3 1.2V (ppm) 429 468 466 460 455 442 477 21 21 21 22 22 22 21 22 23 22 23V 2SE 3.1 9.7 4.4 5.5 5.1 4.5 6.0 0.3 0.3 0.3 0.2 0.2 0.3 0.1 0.3 0.3 0.3 0.3Ni (ppm) 362 383 391 381 375 390 392 27 24 24 24 24 25 24 26 25 24 26Ni 2SE 5.1 8.2 6.0 6.4 5.6 5.8 6.1 0.5 0.3 0.5 0.4 0.3 0.5 0.2 0.3 0.4 0.3 0.4Rb (ppm) 0.57 0.91 0.36 0.25 0.16 4.69 2.10 0.10 0.08 0.16 0.12 0.07 0.29 0.03 0.11 0.06 0.17 0.07Rb 2SE 0.07 0.06 0.06 0.08 0.03 0.55 0.17 0.01 0.01 0.01 0.01 0.00 0.08 0.00 0.01 0.01 0.03 0.01Sr (ppm) 178 223 265 239 248 220 340 9 10 10 9 10 11 9 11 11 14 10Sr 2SE 1.4 4.6 2.0 2.8 3.3 3.1 7.0 0.1 0.2 0.3 0.1 0.1 0.2 0.1 0.1 0.1 1.1 0.1Y (ppm) 2.81 2.59 3.42 3.00 3.37 3.68 3.61 0.11 0.14 0.13 0.11 0.12 0.15 0.14 0.17 0.15 0.15 0.16Y 2SE 0.05 0.04 0.06 0.07 0.07 0.09 0.08 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Zr (ppm) 20.1 18.3 23.5 18.4 21.8 27.3 26.2 0.6 0.8 0.8 0.6 0.7 0.9 0.7 0.9 0.8 0.9 0.8Zr 2SE 0.51 0.49 0.56 0.42 0.47 0.59 0.71 0.02 0.03 0.02 0.02 0.02 0.04 0.02 0.03 0.03 0.03 0.03Nb (ppm) 2.42 1.04 0.76 1.01 0.63 3.73 2.14 0.13 0.16 0.27 0.16 0.18 0.22 0.05 0.15 0.17 0.23 0.13Nb 2SE 0.10 0.04 0.05 0.06 0.03 0.13 0.09 0.01 0.01 0.01 0.01 0.01 0.02 0.00 0.01 0.01 0.02 0.01Ba (ppm) 22.1 18.3 9.0 4.9 12.4 37.2 31.6 1.3 1.3 2.5 1.6 1.8 2.1 0.4 1.3 1.6 3.3 1.3Ba 2SE 1.30 1.20 1.30 0.51 0.77 1.90 1.40 0.11 0.07 0.15 0.07 0.08 0.26 0.04 0.08 0.11 0.67 0.09La (ppm) 4.51 4.87 4.65 4.51 4.29 6.97 8.15 0.22 0.26 0.33 0.23 0.26 0.29 0.17 0.25 0.28 0.31 0.24La 2SE 0.08 0.11 0.09 0.09 0.10 0.14 0.20 0.01 0.01 0.01 0.01 0.01 0.01 0.00 0.01 0.01 0.01 0.01Ce (ppm) 14.1 16.5 15.5 13.7 14.2 19.2 21.0 0.6 0.7 0.8 0.6 0.7 0.7 0.5 0.7 0.7 0.8 0.7Ce 2SE 0.19 0.31 0.18 0.17 0.19 0.37 0.34 0.01 0.01 0.02 0.01 0.01 0.02 0.01 0.01 0.01 0.02 0.01Pr (ppm) 2.17 2.42 2.54 2.31 2.43 3.02 3.11 0.09 0.10 0.11 0.09 0.10 0.11 0.08 0.11 0.11 0.11 0.10Pr 2SE 0.05 0.07 0.05 0.06 0.05 0.07 0.06 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Nd (ppm) 10.6 11.1 12.9 11.8 12.5 14.8 14.8 0.4 0.5 0.5 0.4 0.5 0.5 0.4 0.5 0.5 0.5 0.5Nd 2SE 0.23 0.29 0.33 0.31 0.30 0.36 0.44 0.01 0.02 0.02 0.01 0.01 0.02 0.01 0.01 0.01 0.02 0.02Sm (ppm) 2.35 2.21 2.89 2.56 2.74 3.19 2.87 0.09 0.10 0.10 0.08 0.09 0.11 0.09 0.12 0.11 0.11 0.11Sm 2SE 0.13 0.12 0.15 0.14 0.13 0.19 0.14 0.01 0.01 0.01 0.01 0.00 0.01 0.01 0.01 0.01 0.01 0.01Eu (ppm) 0.59 0.65 0.77 0.73 0.76 0.81 0.87 0.02 0.03 0.03 0.02 0.03 0.03 0.03 0.03 0.03 0.03 0.03Eu 2SE 0.04 0.04 0.03 0.03 0.04 0.04 0.04 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Gd (ppm) 1.56 1.56 2.03 1.85 1.87 2.20 2.25 0.06 0.07 0.08 0.06 0.07 0.08 0.07 0.08 0.08 0.08 0.08Gd 2SE 0.11 0.10 0.10 0.10 0.11 0.17 0.12 0.00 0.01 0.01 0.01 0.00 0.01 0.00 0.01 0.01 0.00 0.01Tb (ppm) 0.18 0.18 0.24 0.20 0.22 0.23 0.25 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Tb 2SE 0.01 0.01 0.02 0.02 0.02 0.02 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Dy (ppm) 0.88 0.81 1.12 0.84 1.10 1.19 1.12 0.03 0.04 0.04 0.03 0.04 0.05 0.04 0.05 0.05 0.04 0.04Dy 2SE 0.06 0.07 0.06 0.06 0.07 0.08 0.07 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Ho (ppm) 0.12 0.12 0.14 0.14 0.14 0.17 0.16 0.00 0.01 0.01 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.01Ho 2SE 0.01 0.01 0.01 0.01 0.01 0.01 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Er (ppm) 0.23 0.22 0.27 0.29 0.29 0.33 0.32 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Er 2SE 0.02 0.02 0.02 0.04 0.03 0.03 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Tm (ppm) 0.02 0.02 0.03 0.02 0.03 0.03 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Tm 2SE 0.01 0.00 0.01 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Yb (ppm) 0.11 0.09 0.13 0.11 0.12 0.14 0.13 0.01 0.01 0.01 0.00 0.01 0.01 0.01 0.01 0.01 0.01 0.01Yb 2SE 0.02 0.02 0.03 0.03 0.02 0.03 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Lu (ppm) 0.02 0.01 0.02 0.01 0.01 0.02 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Lu 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Hf (ppm) 0.90 0.90 1.44 1.19 1.31 1.31 1.48 0.03 0.04 0.04 0.04 0.04 0.05 0.04 0.06 0.05 0.05 0.05Hf 2SE 0.07 0.07 0.08 0.07 0.07 0.08 0.10 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01Ta (ppm) 0.14 0.07 0.06 0.06 0.04 0.22 0.14 0.01 0.01 0.02 0.01 0.01 0.01 0.00 0.01 0.01 0.01 0.01Ta 2SE 0.01 0.01 0.01 0.01 0.01 0.02 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Pb (ppm) 0.53 0.65 0.54 0.56 0.56 0.88 0.89 0.06 0.19 0.10 0.06 0.06 0.06 0.04 0.05 0.04 0.05 0.05Pb 2SE 0.03 0.04 0.03 0.04 0.04 0.06 0.09 0.01 0.02 0.01 0.01 0.01 0.01 0.00 0.01 0.00 0.00 0.00Th (ppm) 0.24 0.12 0.10 0.11 0.06 0.42 0.21 0.01 0.02 0.03 0.02 0.02 0.02 0.00 0.02 0.02 0.02 0.01Th 2SE 0.01 0.01 0.01 0.01 0.01 0.02 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00U (ppm) 0.03 0.02 0.02 0.02 0.02 0.05 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00U 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Values below 0.01 are reported as 0.00. Blank cells indicate measurements where the error exceeded the measured concentrationAppendix C: Trace Element Analyses of Clinopyroxenes110Sample Type Metasomatic Metasomatic Metasomatic Metasomatic Metasomatic Metasomatic Metasomatic Metasomatic Metasomatic MetasomaticSample MOX-31-224.5 MOX-31-224.5 MOX-31-224.5 MOX-31-224.5 MOX-31-224.5 MOX-31-224.5 MOX-31-224.5 MOX-31-224.5 MOX-31-224.5 MOX-31-224.5Spot 1 2 3 4 5 6 7 8 9 10Li (ppm) 0.05 0.08 0.05 0.07 0.09 0.06 0.06 0.05 0.06 0.08Li 2SE 0.00 0.01 0.00 0.00 0.01 0.01 0.01 0.01 0.01 0.00Na (ppm) 1079 1299 1082 1041 1145 1188 1293 1120 1168 1165Na 2SE 25 52 40 20 24 41 40 60 30 22Al (ppm) 762 752 736 731 823 721 728 770 752 732Al 2SE 9.8 20.0 15.0 12.0 12.0 14.0 17.0 18.0 16.0 10.0Si (ppm) 18340 22740 19590 19390 23510 19990 19710 21600 20390 19560Si 2SE 340 980 700 470 420 670 610 1000 540 450K (ppm) 26 75 53 55 91 44 42 28 57 63K 2SE 0.57 4.10 3.30 3.10 5.50 4.70 5.80 1.40 16.00 5.50Sc (ppm) 1.74 1.69 1.73 1.74 1.88 1.67 1.58 1.83 1.75 1.59Sc 2SE 0.02 0.06 0.05 0.04 0.03 0.04 0.04 0.05 0.04 0.03Ti (ppm) 103 110 98 103 120 107 100 102 102 103Ti 2SE 1.3 3.3 2.3 1.7 1.6 2.2 2.3 2.1 2.4 1.5V (ppm) 23.6 27.3 25.6 25.9 24.8 25.9 23.9 24.7 22.2 22.8V 2SE 0.37 1.30 1.20 0.49 0.45 1.50 0.77 1.20 0.74 0.43Ni (ppm) 25.0 36.7 27.6 29.2 44.4 31.2 30.9 29.7 29.2 28.5Ni 2SE 0.60 1.50 0.84 0.73 1.20 1.20 0.87 1.50 0.86 0.57Rb (ppm) 0.02 0.16 0.09 0.10 0.22 0.04 0.01 0.02 0.03 0.07Rb 2SE 0.00 0.01 0.01 0.01 0.02 0.01 0.00 0.00 0.01 0.01Sr (ppm) 9.1 10.5 9.2 9.5 9.1 9.1 8.8 9.1 8.9 9.5Sr 2SE 0.12 0.33 0.25 0.17 0.14 0.20 0.23 0.29 0.22 0.17Y (ppm) 0.13 0.12 0.12 0.13 0.16 0.14 0.12 0.14 0.13 0.12Y 2SE 0.00 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.00 0.00Zr (ppm) 0.58 0.63 0.58 0.59 0.69 0.64 0.61 0.60 0.66 0.65Zr 2SE 0.02 0.04 0.04 0.03 0.03 0.03 0.04 0.03 0.05 0.03Nb (ppm) 0.05 0.12 0.06 0.08 0.04 0.05 0.01 0.07 0.03 0.08Nb 2SE 0.00 0.01 0.01 0.00 0.00 0.00 0.00 0.01 0.00 0.00Ba (ppm) 1.06 2.54 1.16 1.92 2.84 0.60 0.03 1.19 0.30 1.81Ba 2SE 0.10 0.19 0.19 0.08 0.20 0.06 0.01 0.15 0.03 0.11La (ppm) 0.18 0.21 0.20 0.20 0.17 0.18 0.13 0.20 0.15 0.20La 2SE 0.00 0.01 0.01 0.01 0.00 0.01 0.00 0.01 0.00 0.01Ce (ppm) 0.52 0.68 0.64 0.62 0.52 0.58 0.51 0.62 0.53 0.59Ce 2SE 0.01 0.03 0.02 0.02 0.01 0.02 0.02 0.03 0.02 0.01Pr (ppm) 0.08 0.09 0.09 0.09 0.09 0.09 0.08 0.09 0.08 0.09Pr 2SE 0.00 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00Nd (ppm) 0.40 0.42 0.44 0.43 0.44 0.44 0.39 0.45 0.41 0.42Nd 2SE 0.02 0.01 0.02 0.01 0.01 0.02 0.02 0.03 0.02 0.01Sm (ppm) 0.09 0.09 0.09 0.10 0.10 0.10 0.09 0.11 0.09 0.09Sm 2SE 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Eu (ppm) 0.03 0.03 0.03 0.02 0.03 0.03 0.03 0.03 0.03 0.03Eu 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Gd (ppm) 0.07 0.07 0.07 0.07 0.07 0.07 0.06 0.07 0.07 0.07Gd 2SE 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Tb (ppm) 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Tb 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Dy (ppm) 0.04 0.04 0.04 0.04 0.05 0.04 0.03 0.04 0.04 0.04Dy 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.00Ho (ppm) 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Ho 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Er (ppm) 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01 0.01Er 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Tm (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Tm 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Yb (ppm) 0.00 0.01 0.01 0.01 0.01 0.01 0.00 0.01 0.01 0.00Yb 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Lu (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Lu 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Hf (ppm) 0.04 0.04 0.04 0.04 0.05 0.04 0.04 0.04 0.04 0.04Hf 2SE 0.00 0.00 0.00 0.00 0.01 0.00 0.00 0.01 0.01 0.00Ta (ppm) 0.00 0.01 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Ta 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Pb (ppm) 0.03 0.04 0.04 0.04 0.04 0.04 0.04 0.03 0.06 0.05Pb 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.01 0.01Th (ppm) 0.01 0.01 0.01 0.01 0.01 0.01 0.00 0.01 0.00 0.01Th 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00U (ppm) 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00U 2SE 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00Values below 0.01 are reported as 0.00. Blank cells indicate measurements where the error exceeded the measured concentrationAppendix C: Trace Element Analyses of Clinopyroxenes111Sample Type Sample Point Area 208Pb/206Pb 208Pb/206Pb 2SE 207Pb/206Pb 207Pb/206Pb 2SEMegacryst MOX-25-161.5C 1 Core 1.975 0.049 0.792 0.021Megacryst MOX-25-161.5C 2 Core 2.044 0.031 0.799 0.016Megacryst MOX-25-161.5C 3 Core 2.023 0.035 0.799 0.015Megacryst MOX-25-161.5C 4 Core 2.032 0.031 0.808 0.016Megacryst MOX-25-161.5C 5 Core 2.026 0.039 0.817 0.020Megacryst MOX-25-161.5C 6 Core 2.005 0.033 0.818 0.017Megacryst MOX-25-161.5C 7 Rim 2.046 0.034 0.818 0.016Megacryst MOX-25-161.5C 8 Rim 2.092 0.034 0.832 0.016Megacryst MOX-25-161.5C 9 Rim 2.050 0.031 0.819 0.014Megacryst MUSK-3-158.8 1 Core 2.013 0.029 0.820 0.015Megacryst MUSK-3-158.8 2 Core 2.068 0.044 0.813 0.016Megacryst MUSK-3-158.8 3 Core 2.006 0.035 0.790 0.016Megacryst MUSK-3-158.8 4 Core 2.026 0.034 0.820 0.019Megacryst MUSK-3-158.8 5 Core 2.019 0.035 0.813 0.018Megacryst MUSK-3-158.8 6 Core 2.022 0.035 0.809 0.015Megacryst MUSK-3-158.8 7 Core 2.025 0.039 0.811 0.019Megacryst MUSK-3-158.8 8 Core 2.011 0.036 0.812 0.016Megacryst MUSK-3-158.8 9 Core 2.021 0.032 0.808 0.015Megacryst MOX-1-43.35 1 Rim 2.049 0.034 0.819 0.016Megacryst MOX-1-43.35 2 Rim 2.071 0.030 0.827 0.014Megacryst MOX-1-43.35 3 Rim 2.074 0.032 0.821 0.016Megacryst MOX-1-43.35 4 Core 2.037 0.034 0.807 0.015Megacryst MOX-1-43.35 5 Core 2.092 0.037 0.836 0.017Megacryst MOX-1-43.35 6 Core 2.057 0.039 0.811 0.017Megacryst MOX-1-43.35 7 Core 2.039 0.039 0.817 0.016Megacryst MOX-1-43.35 8 Core 2.039 0.037 0.826 0.021Megacryst MOX-1-43.35 9 Core 2.022 0.030 0.810 0.015Appendix D: in situ Pb Isotope Analyses of Clinopyroxenes112Sample Type Sample Point 208Pb/206Pb 208Pb/206Pb 2SE 207Pb/206Pb 207Pb/206Pb 2SEPrimary Clinopyroxene MOX-3-33.0 1 2.293 0.018 0.968 0.008Primary Clinopyroxene MOX-3-33.0 2 2.330 0.016 0.996 0.008Primary Clinopyroxene MOX-3-33.0 3 2.297 0.014 0.977 0.007Primary Clinopyroxene MOX-3-33.0 4 2.248 0.032 0.957 0.015Primary Clinopyroxene MOX-3-33.0 5 2.293 0.012 0.970 0.006Primary Clinopyroxene MOX-3-33.0 6 2.305 0.018 0.980 0.007Primary Clinopyroxene MOX-3-33.0 7 2.287 0.027 0.961 0.012Primary Clinopyroxene MOX-3-33.0 8 2.294 0.028 0.973 0.012Primary Clinopyroxene MOX-3-33.0 9 2.281 0.037 0.961 0.017Primary Clinopyroxene MOX-3-33.0 10 2.217 0.022 0.927 0.008Primary Clinopyroxene MOX-3-33.0 11 2.305 0.017 0.982 0.009Metasomatic Clinopyroxene MOX-7-62.3 1 2.052 0.020 0.820 0.010Metasomatic Clinopyroxene MOX-7-62.3 2 2.059 0.021 0.824 0.008Metasomatic Clinopyroxene MOX-7-62.3 3 2.030 0.013 0.811 0.005Metasomatic Clinopyroxene MOX-7-62.3 4 2.078 0.017 0.837 0.009Metasomatic Clinopyroxene MOX-7-62.3 5 2.053 0.014 0.824 0.007Metasomatic Clinopyroxene MOX-31-224.5 1 2.062 0.021 0.825 0.009Metasomatic Clinopyroxene MOX-31-224.5 2 2.035 0.020 0.819 0.013Metasomatic Clinopyroxene MOX-31-224.5 3 2.037 0.039 0.820 0.013Metasomatic Clinopyroxene MOX-31-224.5 4 2.041 0.021 0.812 0.010Metasomatic Clinopyroxene MOX-31-224.5 5 2.077 0.039 0.830 0.013Metasomatic Clinopyroxene MOX-31-224.5 7 2.060 0.036 0.821 0.015Metasomatic Clinopyroxene MOX-31-224.5 8 2.023 0.033 0.819 0.014Metasomatic Clinopyroxene MOX-31-224.5 9 2.020 0.043 0.817 0.019Metasomatic Clinopyroxene MOX-31-224.5 10 2.065 0.022 0.830 0.010Websteritic Clinopyroxene MOX-24-42.6 1 2.010 0.023 0.804 0.011Websteritic Clinopyroxene MOX-24-42.6 2 2.085 0.032 0.835 0.012Websteritic Clinopyroxene MOX-24-42.6 3 2.063 0.050 0.845 0.019Websteritic Clinopyroxene MOX-24-42.6 4 2.029 0.029 0.806 0.015Websteritic Clinopyroxene MOX-24-42.6 5 2.008 0.033 0.796 0.018Websteritic Clinopyroxene MOX-24-42.6 6 2.037 0.031 0.805 0.016Websteritic Clinopyroxene MOX-24-42.6 7 2.090 0.018 0.844 0.007Websteritic Clinopyroxene MOX-24-42.6 8 2.071 0.017 0.840 0.008Websteritic Clinopyroxene MOX-24-42.6 9 2.061 0.034 0.823 0.014Websteritic Clinopyroxene MOX-24-42.6 10 2.061 0.031 0.817 0.014Websteritic Clinopyroxene MOX-7-30.02 1 2.043 0.019 0.807 0.010Websteritic Clinopyroxene MOX-7-30.02 2 2.064 0.026 0.820 0.013Websteritic Clinopyroxene MOX-7-30.02 3 2.026 0.042 0.812 0.018Websteritic Clinopyroxene MOX-7-30.02 4 2.016 0.040 0.817 0.014Websteritic Clinopyroxene MOX-7-30.02 5 2.030 0.029 0.842 0.021Websteritic Clinopyroxene MOX-24-206.7 1 2.069 0.017 0.841 0.007Websteritic Clinopyroxene MOX-24-206.7 2 2.056 0.014 0.825 0.008Websteritic Clinopyroxene MOX-24-206.7 3 2.068 0.011 0.840 0.004Websteritic Clinopyroxene MOX-24-206.7 4 2.063 0.027 0.837 0.012Websteritic Clinopyroxene MOX-24-206.7 5 2.064 0.027 0.824 0.011Websteritic Clinopyroxene MOX-24-206.7 6 2.036 0.024 0.820 0.010Websteritic Clinopyroxene MOX-24-206.7 7 2.057 0.017 0.822 0.014Websteritic Clinopyroxene MOX-24-206.7 8 2.059 0.021 0.823 0.011Websteritic Clinopyroxene MOX-24-206.7 9 2.046 0.020 0.813 0.011Websteritic Clinopyroxene MOX-24-206.7 10 2.039 0.024 0.811 0.012Websteritic Clinopyroxene MOX-24-206.7 11 2.015 0.018 0.798 0.009Websteritic Clinopyroxene MOX-24-206.7 12 2.066 0.024 0.818 0.015Appendix D: in situ Pb Isotope Analyses of Clinopyroxenes113Appendix E: Pb-Pb model ages for Muskox samples calculated using IsoplotR (Vermeesch 2018) plotted with the Stacey-Kramers two stage Pb evolution curve (Stacey and Kramers 1975). (a) Model age for Muskox kimberlite, clinopyroxene megacrysts and websteritic clinopyroxene compared with (b) the model age calculated for Muskox clinopyroxene megacrysts and websteritic clinopyroxene. MSWD = Mean square weighted deviation. Appendix E: Pb-Pb Isochrons114Appendix F: (a) 87Sr/86Sr vs. 206Pb204Pb for Muskox samples displaying no discernable correlations. (b-d) elemental concentration (ppm) vs isotopic ratios of Muskox samples calculated for isotopic mixing models (dashed lines). 0 50 100 150 200Nd (ppm)0.51120.51140.51160.51180.51200.51220.51240.51260.5128143 Nd/144 NdHIMU1% 5% 10%20% 30% 40% 50% 60% 70%0.7034 0.7038 0.7042 0.704687Sr/86Sr16.016.517.017.518.018.519.0206 Pb/204 Pb0 5 10 15 20 25Pb (ppm)16.017.018.019.020.021.0206 Pb/204 Pb5% 10%EM1HIMU30% 40% 50%20% 60% 70%- Primary clinopyroxene- Websteritic clinopyroxene- Muskox kimberlite- Jericho kimberlite- Clinopyroxene megacrysts1%0 200 400 600 800 1000Sr (ppm)0.70250.70300.70350.70400.70450.705087Sr/86SrHIMUEM11%5%10%20% 30% 40% 50% 60% 70%EM1a. b.c. d.Appendix F: Supplementary Isotopic Mixing Figures115"@en ; edm:hasType "Thesis/Dissertation"@en ; vivo:dateIssued "2021-05"@en ; edm:isShownAt "10.14288/1.0395184"@en ; dcterms:language "eng"@en ; ns0:degreeDiscipline "Geological Sciences"@en ; edm:provider "Vancouver : University of British Columbia Library"@en ; dcterms:publisher "University of British Columbia"@en ; dcterms:rights "Attribution-NonCommercial-NoDerivatives 4.0 International"@* ; ns0:rightsURI "http://creativecommons.org/licenses/by-nc-nd/4.0/"@* ; ns0:scholarLevel "Graduate"@en ; dcterms:title "Crystallization of megacrysts by carbonatitic metasomatism : evidence from the Muskox kimberlite, Nunavut, Canada"@en ; dcterms:type "Text"@en ; ns0:identifierURI "http://hdl.handle.net/2429/76700"@en .