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Petrochronological constraints on the origin of the Salt Lake Crater garnet-bearing pyroxenite xenoliths,… Zhang, Zhen 2017

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	 PETROCHRONOLOGICAL CONSTRAINTS ON THE ORIGIN OF THE SALT LAKE CRATER GARNET-BEARING PYROXENITE XENOLITHS, OAHU, HAWAII by Zhen Zhang  A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF  THE REQUIREMENTS FOR THE DEGREE OF  MASTER OF SCIENCE in The College Of Graduate Studies  (Environmental Sciences)   THE UNIVERSITY OF BRITISH COLUMBIA  (Okanagan)   June 2017 © Zhen Zhang, 2017   	 ii	The following individuals certify that they have read, and recommend to the College of   Graduate Studies for acceptance, a thesis entitled:    PETROCHRONOLOGICAL CONSTRAINTS ON THE ORIGIN OF THE SALT LAKE CRATER GARNET-BEARING PYROXENITE XENOLITHS, OAHU, HAWAII         submitted by  Zhen Zhang           in partial fulfillment of the requirements of  the degree of  Master of Science     .   Dr. John Greenough, Irving K. Barber School of Arts and Sciences                         Supervisor   Dr. Kyle Larson, Irving K. Barber School of Arts and Sciences                            Supervisory Committee Member    Dr. Yuan Chen, Irving K. Barber School of Arts and Sciences                             Supervisory Committee Member   Dr. Paul Shipley, Irving K. Barber School of Arts and Sciences                            University Examiner   Dr. John Hopkinson, Irving K. Barber School of Arts and Sciences                          External Examiner  	 iii	Abstract  This thesis reports the results of a comprehensive major and trace element study of seven garnet-bearing pyroxenite xenoliths recovered from Oahu, Hawaii. The pyroxenites are dominated by clinopyroxene, but also contain garnet, olivine, orthopyroxene and spinel (Cpx, Gt, Ol, Opx, Sp). Four zircons extracted from two pyroxenites have been dated and the trace element signatures studied in detail. Petrological and geochemical information from optical microscopy, electron microprobe analysis (EMP; 11 major and minor element oxides) and Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS; 36 trace elements) for major mineral phases indicate that the pyroxenites are cumulates formed through fractional crystallization of magma formed by partial melting of a subcontinental lithospheric mantle fragment entrained in the convecting oceanic lithosphere. Two groups of ages were acquired from zircon core and rim zones, with simultaneous, in situ, determination of trace element concentrations by a cutting-edge Laser Ablation Split Stream-ICP-MS technique. They are the first zircons yielding true ages (non-model ages) for xenoliths recovered from the oceanic lithospheric mantle. The older core (80.8 ± 2 Ma) of Zircon3 yielded clinopyroxene/zircon, garnet/zircon partitioning coefficients for most elements that match literature coefficients for 	 iv	similar magma types. This suggests that clinopyroxene and garnet, the dominant minerals in the xenoliths, formed during a magmatic event ~ 81 Ma, when the zircon cores formed. Younger ages (12.9 ± 0.2 Ma to 14.5 ± 0.2 Ma) given by four zircons (Zircon2 and Zircon4, along with overgrowths on Zircon1 and Zircon3) are inferred to record a event at ~ 13 Ma, possibly due to the presence of an adjacent mantle plume. The result implies that instead of recycled oceanic crust and lithosphere, the removal of mantle lithosphere from below the continents during subduction or asthenosphere upwelling could be an important mechanism that contributes to chemical variability in the mantle.   	 v	Preface  This thesis is my own work. Dr. John Greenough designed the research program and gave research directions. He was also involved in discussion and editing. Dr. John Cottle helped acquire and process geochronology data. He also composed text describing the LASS-ICP-MS operation.    	 vi	Table of Contents Abstract ....................................................................................................................................... iii	Preface .......................................................................................................................................... v	Table of Contents ........................................................................................................................ vi	List of Tables ............................................................................................................................... ix	List of Figures ............................................................................................................................. xi	List of Abbreviations ................................................................................................................ xiii	Acknowledgements ................................................................................................................... xiv	CHAPTER Ⅰ INTRODUCTION ........................................................................................... 1	CHAPTER Ⅱ  BACKGROUND .............................................................................................. 4	2.1 Geological Setting .............................................................................................................. 4	2.2 Sampling and Pervious Work ........................................................................................... 6	2.3 Previous Research .............................................................................................................. 9	CHAPTER Ⅲ  ANALYTICAL TECHNIQUES ................................................................... 12	3.1 Petrographic Analyses ..................................................................................................... 12	3.2 Major Elements from EMPA ......................................................................................... 12	3.3 Trace Element Concentrations from LA-ICP-MS ....................................................... 15	3.4 Zircon Dating and Trace Element Concentration Profiling ........................................ 20	CHAPTER Ⅳ  RESULTS ....................................................................................................... 22	4.1 Petrography ...................................................................................................................... 22	4.2 Elemental Mapping ......................................................................................................... 27	4.3 Major Element Mineral Analyses .................................................................................. 28	4.3.1 Clinopyroxene ............................................................................................................ 29	4.3.2 Orthopyroxene ............................................................................................................ 32		 vii	4.3.3 Garnet ......................................................................................................................... 34	4.3.4 Olivine ........................................................................................................................ 35	4.4 Trace Elements ................................................................................................................ 36	4.4.1 Clinopyroxene ............................................................................................................ 36	4.4.2 Garnets ........................................................................................................................ 39	4.5 Zircon Petrochronological Signatures ........................................................................... 40	4.5.1 Morphology and texture of zircons ............................................................................ 40	4.5.2 Zircon1 Age and Trace Element Data ........................................................................ 41	4.5.3 Zircon2 Age and Trace Element Data ........................................................................ 45	4.5.4 Zircon3 Age and Trace Element Data ........................................................................ 48	4.5.5 Zircon4 Age and Trace Element Data ........................................................................ 50	CHAPTER Ⅴ  DISCUSSION ................................................................................................. 53	5.1 Genetic Relationships ...................................................................................................... 53	5.2 Origin of SLC Xenoliths .................................................................................................. 55	5.2.1 Frozen melt ................................................................................................................. 56	5.2.2 Recycled oceanic crust ............................................................................................... 58	5.2.3 Cumulate origin .......................................................................................................... 58	5.3 Source Melt and Petrognesis of Clinopyroxene and Garnet ....................................... 59	5.3.1 Melt composition ........................................................................................................ 59	5.3.2 Pb enrichment and association with subcontinental lithospheric mantle ................... 62	5.3.3 Local Pb anomaly in Cpx ........................................................................................... 63	5.4 Significance of Zircon Ages ............................................................................................ 64	5.4.1 Zircon Associated Mineral ......................................................................................... 64	5.4.2 Magmatic vs. metamorphic origin of zircon cores and rims ...................................... 70	5.4.3 Interpretation of ages .................................................................................................. 75	5.5 Tectonic Implications ...................................................................................................... 76		 viii	CHAPTER Ⅵ CONCLUSIONS ............................................................................................ 79	REFERENCES .......................................................................................................................... 80	APPENDICES ............................................................................................................................ 93	Appendix A Detailed Sample Processing and Extraction Procedures .............................. 93	Appendix B Mineral Composition Data .............................................................................. 97	   	 ix	List of Tables Table 1 Major Element Compositions of Standards .............................................................. 14	Table 2 Precision and Accuracy of Each Major Element ...................................................... 15	Table 3 LA-ICP-QMS Operating Parameters ........................................................................ 16	Table 4 Order of Measurements .............................................................................................. 17	Table 5 Analyses of BCR-2G .................................................................................................... 19	Table 6 Petrographic Features of Seven SLC Samples .......................................................... 24	Table 7 SEM-EDX Composition of the Unknown Phase ....................................................... 27	Table 8 Summary of Ages of Four Zircons ............................................................................. 41	Table 9 Partition Coefficients from the Literature Used to Construct the Reference Line in Figure 26 .............................................................................................................................. 66	Table 10 Major Element Concentrations and Calculated Stoichiometry for Clinopyroxene .............................................................................................................................................. 97	Table 11 Major Element Concentrations and Calculated Stoichiometry for Orthopyroxene ............................................................................................................................................ 101	Table 12 Major Element Concentrations and Calculated Stoichiometry for Garnet ....... 103	Table 13 Major Element Concentrations and Calculated Stoichiometry for Olivine ....... 107	Table 14 Major and Trace Element Concentrations for Clinopyroxene from LA-ICP-MS ............................................................................................................................................ 109	Table 15 Major and Trace Element Concentrations for Garnet from LA-ICP-MS ......... 115	Table 16 Ages (Ma) of 4 Zircons with Correlated Drilling Depth ...................................... 121	Table 17 Mean Age of Four Zircons ...................................................................................... 131	Table 18 LA-ICP-MS Depth Profiling Trace Element Concentrations for Zircon1 (SLCX 47) ....................................................................................................................................... 132	Table 19 LA-ICP-MS Depth Profiling Trace Element Concentrations for Zircon2 (SLCX 47) ....................................................................................................................................... 134	Table 20 LA-ICP-MS Depth Profiling Trace Element Concentrations for Zircon3 (SLCX 12) ....................................................................................................................................... 136		 x	Table 21 LA-ICP-MS Depth Profiling Trace Element Concentrations for Zircon4 (SLCX 12) ....................................................................................................................................... 138	   	 xi	List of Figures Figure 1 Sketch map showing location of the Salt Lake Crater on the island of Oahu.. ...... 5	Figure 2 Sample photos of the SLCX 45 hand sample. ............................................................ 7	Figure 3 The four zircons involved in this project ................................................................... 9	Figure 4 Plane polarized photomicrographs of representative mineral assemblages and textures ................................................................................................................................ 25	Figure 5 Photograph of the unknown phase ........................................................................... 26	Figure 6 Back Scattered Electron Image and elemental maps of SLCX 26 garnet ............. 28	Figure 7 Compositions of SLCX clinopyroxenes and orthopyroxenes. ................................ 30	Figure 8 Plots of Mg# versus major element oxides for clinopyroxenes .............................. 31	Figure 9 Plots of Mg# versus major element oxides for orthopyroxenes ............................. 33	Figure 10 Ternary diagram of garnet compositions ............................................................... 35	Figure 11 Primitive mantle normalized trace element abundances in SLC clinopyroxenes .............................................................................................................................................. 38	Figure 12 Mg# vs. compatible elements (Sc, Ni) and incompatible elements (Sr, Nb) in clinopyroxenes .................................................................................................................... 39	Figure 13 Primitive mantle normalized trace element abundances in SLC garnets ........... 40	Figure 14 Chondrite-normalized Hf, Y and U concentrations and age profiling data for Zircon1 ................................................................................................................................ 42	Figure 15 Chondrite-normalized REE patterns for Zircon1 ................................................. 44	Figure 16 Chondrite-normalized Hf, Y and U concentrations and age profiling data for Zircon 2 ............................................................................................................................... 46	Figure 17 Chondrite-normalized REE pattern for Zircon2 .................................................. 47	Figure 18 Chondrite-normalized Hf, Y and U concentrations and age profiling data for Zircon3 ................................................................................................................................ 48	Figure 19 Chondrite-normalized REE patterns for Zircon3 ................................................. 50	Figure 20 Chondrite-normalized Hf, Y and U concentrations and age profiling data for Zircon4 ................................................................................................................................ 51	Figure 21 Chondrite-normalized REE pattern for Zircon4 .................................................. 52		 xii	Figure 22 Multi-dimensional scaling comparisons of seven samples based on the overall major, minor and trace element composition of clinopyroxene. .................................... 54	Figure 23 Zr/Hf vs. Nd/Sm ratios of clinopyroxene in peridotite and pyroxenite from the Salt Lake Crater ................................................................................................................. 57	Figure 24 Primitive mantle-normalized trace element composition of melts in equilibrium with clinopyroxene ............................................................................................................. 60	Figure 25 Cpx/Gt partitioning coefficients for REE .............................................................. 62	Figure 26 Diagram showing zircon/clinopyroxene partition coefficients for REE in samples SLCX 47 and SLCX 12 ...................................................................................................... 67	Figure 27 Diagram showing zircon/garnet partition coefficients for REE in samples SLCX 47 and SLCX 12 .................................................................................................................. 69	Figure 28 Th/U vs. depth profile of two zircon cores ............................................................. 72	Figure 29 Th/U vs. depth profile of zircon rims ...................................................................... 74	Figure 30 SLCX processing photos. ......................................................................................... 94	 	 xiii	List of Abbreviations Alm  Almandine Bld.  Below detecting limit BSE  Back-Scattered Electron Cpx  Clinopyroxene EBS  Electron Back Scatter Image EDS  Energy Dispersive Spectroscopy EMP  Electron Microprobe En  Enstatite Fa  Fayalite Fo  Forsterite Fs  Ferrosilite Grs  Grossular Gt  Garnet HREE  Heavy Rare Earth Elements LA-ICP-MS  Laser Ablation Inductively Coupled Plasma Mass Spectroscopy LASS  Laser Ablation Split Stream LREE  Light Rare Earth Elements MREE  Middle Rare Earth Elements Ol  Olivine Opx  Orthopyroxene PPL  Plane-Polarized Light Prp  Pyrope REE  Rare Earth Elements RL  Reflected Light SLC  Salt Lake Crater SCLM  Subcontinental Lithospheric Mantle Sp  Spinel WDS  Wavelength Dispersive Spectroscopy Wo  Wollastonite XPL  Cross-Polarized Light    	 xiv	Acknowledgements  First and foremost, this project was made possible by the support and encouragement from supervisor Dr. John Greenough. His constant effort ensured the lab work was always on schedule and my questions could be quickly answered. He also sets a good example on hard-working and critical thinking. What I have learned from him will benefit me for my whole life. Sincerest thanks to him.  I would also like to thank every researcher and technician who has helped me. Thanks go to my committee members, Dr. Kyle Larson and Dr. Yuan Chen for valuable advice and feedback during the project. Dr. Daniel Layton-Matthews at Queen's University crushed the samples. Dr. Don Davis, Dr. Sandra Kamo and Yim Ying (Kim) Kwok at University of Toronto helped with zircon separation and preliminary dating. Thank David Arkinstall at UBC O for help on SEM and EMP analyses. Thanks go to Dr. Brain Fryer, Dr. Joel Gagnon, J.C. Barrette and Janet Hart at University of Windsor for help on LA-ICP-MS and data reduction. Dr. John Cottle at University of California performed the zircon petrochronology data.   I would like to thank the Department of Mineral Sciences of the Smithsonian Institution for providing reference materials USNM 111356, USNM 111356 and USNM 111312. I thank Dr. David Clague for assistance in identifying the sampling locality, and EESC 2004 students for helping collect the xenoliths.   This project was funded by NSERC and UBC O graduate fellowships.  Last but not least, I would like to thank my parents for their mental and financial support on my abroad research and life. Without them, I would not have the chance to come to Canada and 	 xv	investigate the fantastic place in the past four years. I would like to thank my friend and roommate Wayne for showing me Canadian culture and beauty. Finally, I thank my girlfriend Jing for always being with me.       	 1	CHAPTER Ⅰ INTRODUCTION  The famous garnet bearing pyroxenite xenoliths from the Salt Lake Crater (SLC), Oahu, Hawaii, have been widely studied for nearly four decades (Bizimis et al., 2013; 2005; Clague, 1987; Frey, 1980; Keshav and Sen, 2003; Keshav et al., 2007; Lassiter et al., 2000; Peslier et al., 2015; Sen et al., 1993). People are interested in these xenoliths because they represent samples of the mantle below Oahu, but more importantly, they are the deepest-origin rocks yet formed in the ocean basins. These samples carry critical information about the chemical and physical composition of the mantle, or the mantle-crust transition boundary, and have been treated as probes of chemical variability in the mantle. Two groups of nano-diamonds were reported from the SLC pyroxenites (Frezzotti and Peccerillo, 2007; Wirth and Rocholl, 2003). The discovery of diamonds indicates that the samples may be a result of subduction of oceanic lithosphere billions of years ago, or recent removal of ancient subcontinental lithospheric mantle (SLM) from below the continents during Phanerozoic subduction or rifting. 	 2	 Several geologists have examined the petrology and chemical composition of the SLC xenoliths in detail in the past decades. The samples are classified as garnet clinopyroxenites with clinopyroxene dominating the mineral assemblage, along with the presence of garnet, orthopyroxene, olivine and spinel (Keshav and Sen, 2003). Major and trace element systematics and the presence of cumulate textures in some samples suggest that the SLC pyroxenites are cumulates formed as a result of high pressure fractional crystallization (Bizimis et al., 2005). The depth where the samples formed is controversial (Bizimis and Peslier, 2015; Keshav and Sen, 2004; Keshav et al., 2005), but they are generally considered to come from the lower oceanic lithospheric mantle. Geobarometry on a few samples yielded asthenospheric depths (Keshav and Sen, 2003). Based on Lu-Hf and Nd-Sm isotopic systematics, Bizimis suggested that these xenoliths have a near-zero age and formed right before being brought to the surface (Bizimis et al., 2005). However, this estimate is not necessarily robust because secondary alteration or metamorphism can reset the isotope pairs.   In the fall of 2015, seven zircons were extracted from two garnet pyroxenite xenoliths. With recent cutting-edge techniques such as LA-ICP-MS (Laser Ablation Inductively Coupled Plasma 	 3	Mass Spectrometry) and the newly developed LASS-ICP-MS (Laser Ablation Split-Stream Inductively Coupled Plasma Mass Spectrometry) method, we are able to acquire zircon U-Pb ages along with in situ trace element concentrations, which carry information on the conditions where the samples formed. This research investigates the relationships between the ages, the rock-forming phases and associated geological events. The results bring new insights to our understanding of the geodynamic processes occurring within the oceanic lithosphere.    	 4	CHAPTER Ⅱ  BACKGROUND 2.1 Geological Setting     The Hawaiian Island Chain in the North Pacific Ocean is composed of numerous volcanic islands that young toward the South East. The Hawaiian island chain is thought to be the surface expression of an upwelling mantle plume, which heats up the older lithosphere (~ 100 Ma) and leads to extensive intra-plate volcanism (Hart et al., 1992; Ren et al., 2005; Ribe, 1988). The chain was initiated ~ 80 Ma, and north-westward movement of the Pacific oceanic plate has left a trail of islands and seamounts. Oahu, which is the third largest island of the Hawaiian Island chain, occupies a total area of 1545 km2. The Oahu island has an age of ~ 5 Ma, and was built due to the eruption of the Waianae and Koolau volcanoes. The Koolau caldera was formed due to tholeiitic lava eruptions between 1.8 and 2.6 Ma, and this shield building stage was followed by and erosional stage lasting 1.8 Myr (Clague, 1987; Frey, 1980; Lanphere and Dalrymple, 1980; Lassiter et al., 2000; Sen et al., 1993). The crust was thinned during the erosional stage, which ultimately triggered decompression melting during a rejuvenated stage that began at 0.6 Ma, producing the Honolulu Volcanics (HV) at several vents scattered across the caldera 	 5	(Lassiter et al., 2000; Rocholl et al., 1996; Sen and Jones, 1990). One of the vents, the Salt Lake Crater, located on the flank of the caldera, is the place where the SLCX samples were recovered (Figure 1).              Figure 1 Sketch map showing location of the Salt Lake Crater on the island of Oahu. Modified from Google Earth.      Xenoliths of dunite, spinel lherzolite and pyroxenite are common at the vents. Dunites are recovered at or close to the Koolau caldera vents, whereas spinel lherzolites are spread out around the caldera (Bizimis et al., 2004; Clague and Frey, 1982; Keshav et al., 2007; Sen and Jones, 1990; Sen et al., 1993). Garnet-bearing pyroxenites, unlike dunites and lherzolites, only occur at the Salt Lake Crater, where spinel lherzolite and garnet-bearing pyroxenite are the dominant xenolith types (Bizimis et al., 2005; Frey, 1980; Keshav et al., 2007). In most cases the 	 6	pyroxenite is hosted in nephelinitic tuff (Clague and Frey, 1982), and lherzolite usually occurs together with pyroxenite (Keshav and Sen, 2003).  2.2 Sampling and Pervious Work     The seven samples (SLCX 11, SLCX 12, SLCX 21, SLCX 25, SLCX 26, SLCX 45, SLCX 47) (Figure 2) included in this project were selected from a suite of 48 xenoliths (SLCX 1-48) collected by Dr. John Greenough and UBC O students during a 2004 trip to the Salt Lake Crater. The recovery location lies behind the Hoaloha Park, on the slope of a small hill (21°21.174’ N, 157°54.727’ W, 28 m). Samples include lherzolite, pyroxenite, and host basalt. In anticipation of doing Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS), thick sections (200 µm) were cut to permit laser drilling on small grains if necessary. 	 7	            Figure 2 Sample photos of the SLCX 45 hand sample.      In 2013, a major element and trace element focused honours project (Rusk, 2013) studied garnet and pyroxene compositions in five xenoliths from the SLCX suite. The major element results outlined two populations of subtly distinct garnet pyroxenite xenoliths. The low Cr (< 1 %) and high Ca (~ 5 %) concentrations from garnet resemble those found in diamond bearing kimberlitic pipes. REE diagrams from LA-ICP-MS trace element data also show similarities to diamond associated garnets. These observations, together with the previous nano-diamond 	 8	discovery (Wirth and Rocholl, 2003), indicated that the SLCX samples are potentially ancient, and may even have subcontinental lithospheric mantle origin.       Neither petrography, Energy Dispersive Spectroscopy mapping, nor Back-Scatter Scanning Electron Microscopy imaging revealed zircons for in-situ dating; whole-sample separation was required. In August 2015, seven golf-ball to fist-sized samples were disaggregated using the Queen's University selFrag and mineral separation was conducted at the University of Toronto the following month. Seven datable zircons were discovered in two of the seven samples, with four from SLCX 12 and three from SLCX 47. See Appendix A for details in processing procedures. Preliminary dating by LA-ICP-MS returned ages between 12 Ma (from rim), and 70 Ma (from core). Three of the seven zircons were dissolved for isotopic research, and the remaining four (Figure 3), which are involved in this project, were sent to the University of California for further dating and trace element analysis.  	 9	              Figure 3 The four zircons involved in this project. Photo taken by Dr. Sandra Kamo, University of Toronto.  2.3 Previous Research  The SLC garnet-bearing pyroxenite xenoliths have attracted significant research interest during the past four decades. The presence of garnets in the mineral assemblage suggests a deep lithosphere to upper mantle asthenosphere origin (Bizimis et al., 2005; Frey, 1980; Frezzotti et al., 1992; Keshav et al., 2007; Lassiter et al., 2000). In 2003, nanocrystalline diamonds were found in silicate melt inclusions (Wirth and Rocholl, 2003), suggesting that at least some of the pyroxenite samples were derived from great mantle depths (> 150 km), though metastable diamonds can apparently form at lithospheric depths. This great depth proposal was strengthened 	 10	by another pyroxenite nano-diamond discovery in 2007 (Frezzotti and Peccerillo, 2007), but in this case the diamonds were recovered from carbonate melt inclusions.   Based on more recent studies, the garnet-bearing pyroxenites are generally thought to be high pressure cumulates formed by fractional crystallization of melts that chemically resemble HV lavas (Bizimis et al., 2005; Frey, 1980; Keshav et al., 2007; Sen and Jones, 1990). This conclusion is supported by a layered 'cumulate' texture, high Fe/Mg ratios, low abundances of incompatible elements and Hf-Nd-Sr-Pb systematics. Although it is agreed that the xenoliths represent samples of the mantle beneath Oahu, the depth where crystallization happened is controversial (Keshav and Sen, 2003; Keshav et al., 2007; Lassiter et al., 2000; Sen et al., 2005), and estimates vary from the lower lithospheric mantle to asthenosphere.   So far, no U-Pb zircon geochronology data on the SLC xenoliths have been published in the literature because zircons have never been found. Based on the radiogenic Os composition and the positive correlation between 187Os/188Os and 187Re/188Os ratios, it was inferred that the pyroxenite xenoliths formed at 80-100 Ma, with the formation of the oceanic lithosphere beneath Oahu (Lassiter et al., 2000). However, recent work suggests that the high abundance of 	 11	unradiogenic Os was produced by sulphide assimilation (Sen et al., 2010). Bizimis et al. (2005) suggested that, based on Lu-Hf and Sm-Nd isotopic equilibrium between garnet and clinopyroxene and the reconstructed bulk rock composition, the garnet-bearing pyroxenite xenoliths should have a near zero-age, thus they cannot have formed at ~ 100 Ma at the Pacific mid ocean ridge. However, in a study on spinel lherzolite (occurring together with the pyroxenite) conducted by the same research group, it was suggested that the lherzolites represent ancient (> 2 Ga) recycled lithosphere entrained in the mantle plume based on a Hf-Os isotopic study (Bizimis et al., 2007). Considering that the pyroxenites can occur as veins in lherzolite, the great variation in model ages between the two rock types lead to doubt about the validity of these model ages. The ages assumed that there was no alteration after formation of the rock, which might be invalid if HV melts have metasomatized these xenoliths during the transportation process (Ducea et al., 2002). Therefore, the zircon U-Pb ages given by this study and associated zircon, garnet and clinopyroxene geochemistry have the potential to provide new insights into the formation of these xenoliths.    	 12	CHAPTER Ⅲ  ANALYTICAL TECHNIQUES 3.1 Petrographic Analyses  Petrographic analysis was conducted using a Nikon LV100 petrographic microscope, with photos taken using a Nikon D300 digital camera attached to the microscope. Prior to the electron microprobe (EMP) work, a Tescan Mira3 XMU Field Emission Scanning Electron Microscope with an Oxford Aztec X-Max energy-dispersive spectrometer (EDS) system was used to study the thin sections, identify minerals and select grains for EMP analyses. An Oxford Instruments Nordlys electron backscattered detector (EBSD) supplied back-scatter images. 3.2 Major Elements from EMPA  Major element concentrations of clinopyroxene, orthopyroxene, garnet and olivine were acquired using wavelength dispersive spectroscopy on a Cameca SX5 Field Emission Electron Microanalyser (EMP) at the University of British Columbia, Okanagan, Fipke Laboratory for Trace Element Research (FiLTER), in Kelowna, British Columbia, Canada. The EMP analyses were made at 15 keV accelerating voltage, with a 20 nA beam current, and a 10 µm beam size. 	 13	Each oxide was calibrated by a standard with known and relatively abundant major element concentrations. Ti, Na and K were calibrated on hornblende, Ca was calibrated on apatite, Si was calibrated on omphacite, Mn used spessartine garnet, Cr was calibrated on chromite, Fe and Mg were calibrated on olivine, Ni used millerite and Al was calibrated on almandine garnet.   The EMP work was completed in three days. In most cases three analyses were attained on each mineral in each of the seven slides, and an average composition calculated. Duplicates and repeat measurements were made on different days. Smithsonian olivine, anorthite and hornblende with known composition (Table 3.1) served as external standards to determine precision and accuracy, and check performance of the instrument. Eight measurements were performed on each mineral, four at the start and four at the end of the analysis periods. Precision and accuracy are reported in Table 3.2 as percent relative standard deviation (%RSD) and mean percent error (MPE) with calculation equations in the Table 2.2 footnote. Accuracy and precision for major oxides (> 5 wt%) of each day's measurement are better than ± 5 % and 2 %, respectively (Table 3.2). As a check on data quality, all clinopyroxene, garnet, orthopyroxene and olivine analyses from the xenoliths had major element oxide totals between 98.5 wt% and 	 14	101.5 wt%. As a further check, stoichiometry was calculated on the basis of 6 O for Cpx and Opx, 12 O for garnet and 4 O for olivine, and all analyses have total cations within ± 2 % of the ideal number.  Table 1 Major Element Compositions of Standards  Hornblende (wt%) Anorthite (wt%) Olivine (wt%) SiO2 41.46 44.00 40.81 Al2O3 15.47 36.03  Fe2O3 5.60   FeO 6.43 0.62 9.55 MgO 14.24 0.02 49.42 CaO 11.55 19.09 0.05 Na2O 1.91 0.53  K2O 0.21 0.03  TiO2 1.41 0.03  P2O5 0.01  0.00 MnO 0.15  0.14 Cr2O3    NiO   0.37 H2O 1.21   Total 99.64 100.33 100.29 *Reference minerals were provided by the Department of Mineral Sciences of the Smithsonian Institution. 	 15	Table 2 Precision and Accuracy of Each Major Element 	 Day1	 	 	 Day2	 	 	 Day3	 	 	 Standard	Oxide	Mean	(wt%)	MPE	%	 %RSD	Mean	(wt%)	MPE	%	 %RSD	Mean	(wt%)	MPE	%	 %RSD	Recommend	(wt%)	SiO2	 43.92	 -0.19	 0.42	 43.80	 -0.46	 0.30	 43.71	 -0.66	 0.61	 44.00	TiO2	 1.45	 2.48	 1.92	 1.42	 0.80	 2.11	 1.42	 0.98	 1.06	 1.41	Al2O3	 35.61	 -1.16	 0.48	 35.63	 -1.11	 0.36	 35.02	 -2.81	 0.47	 36.03	Cr2O3	 0.01	 	 73.24	 0.01	 	 37.03	 0.02	 	 79.68	 0.00	FeO	 9.84	 3.05	 0.70	 9.90	 3.69	 1.32	 9.83	 2.97	 0.88	 9.55	MnO	 0.12	 -18.33	 35.92	 0.15	 -3.33	 11.66	 0.13	 -10.83	 11.26	 0.15	NiO	 0.35	 -5.41	 9.04	 0.36	 -3.72	 15.15	 0.38	 1.69	 6.80	 0.37	MgO	 49.17	 -0.50	 0.55	 49.28	 -0.29	 0.39	 49.23	 -0.38	 0.32	 49.42	CaO	 19.67	 3.05	 0.58	 19.59	 2.61	 0.43	 19.48	 2.06	 0.39	 19.09	Na2O	 2.27	 18.91	 1.70	 2.27	 18.72	 1.02	 2.27	 19.04	 0.94	 1.91	K2O	 0.22	 5.95	 7.50	 0.22	 3.57	 5.36	 0.22	 3.57	 7.27	 0.21	*Total Fe is given as FeO. MPE% = mean percent error = !""%!  * !"#$%&"' (!)!!"#$%%"&'!"#$%%"&'!!!! , where n = total number of measurements = 8, t = number of measurements, measured values are given in Appendix B. %RSD = relative standard deviation = !"# !"#$%& !"#$%#&% !"#$%&$'(!"#$%& !"#$  *100%.   3.3 Trace Element Concentrations from LA-ICP-MS  The trace element composition of clinopyroxene, orthopyroxene, garnet and olivine was determined using a laser ablation inductively coupled plasma quadrupole mass spectrometry (LA-ICP-QMS) system at the University of Windsor, Great Lakes Institute for Environmental Research (GLIER), Windsor, Ontario, Canada. The system comprises a Photon machines Excite 193 ultra short pulse Argon Floride Excimer laser ablation system coupled to an Agilent 7900 	 16	fast-scanning quadrupole inductivity coupled plasma mass spectrometres (ICP-QMS). A mixed gas flow with argon and helium was used to deliver the aerosol generated in the ablation chamber to the ICP-QMS. The operating parameters are listed in Table 3.3.  Table 3 LA-ICP-QMS Operating Parameters LA-ICP-QMS parameters Unit Value RF power W 1250 Carrier gas flow rate (Ar) L/min 0.8 Cell gas flow rate (He) L/min 0.36 Sampling arm gas flow rate (He) L/min 0.84 Laser fluence (energy) J/cm2 3.46 (50 %) Laser rep rate Hz 20 Spot size µm 25 Scan pattern  line & spot Scan rate µm/s 5  Due to the small size of three target minerals in SLCX 12, measurements on the seven samples were completed in three runs. The measurement sequence (sample and standards) is listed in Table 3.4. Forty one elements, including major elements and trace elements, were quantified. The signal file generated from the LA-ICP-MS was reduced with IOLITE software to yield actual element concentrations. NIST SRM 610 served as an external standard using the concentrations in (Jochum et al., 2011). Si concentrations from EMP analyses of all minerals acted as the internal standard for the 36 reported trace elements.    	 17	Table 4 Order of Measurements Run	 Thin	Section/Standard	 Laser	Mode	 Mineral	1	 NIST	610	 Linear	 	1	 NIST	610	 Linear	 	1	 BCR-2G	 Linear	 	1	 BCR-2G	 Linear	 	1	 SLCX	26	 Linear	 2	Cpx,	1	Opx,	1	Gt	1	 SLCX	47	 Linear	 4	Cpx,	3	Gt,	2	Ol	1	 SLCX	25	 Linear	 3	Cpx,	3	Opx,	2	Gt,	1	Ol	1	 SLCX	12	 Linear	 2	Cpx,	2	Opx,	2	Gt	1	 NIST	610	 Linear	 	1	 NIST	610	 Linear	 	1	 BCR-2G	 Linear	 	1	 BCR-2G	 Linear	 	2	 NIST	610	 Spot	 	2	 NIST	610	 Spot	 	2	 BCR-2G	 Spot	 	2	 BCR-2G	 Spot	 	2	 SLCX	12	 Spot	 1	Cpx,	1	Opx,	1	Gt	2	 NIST	610	 Spot	 	2	 NIST	610	 Spot	 	2	 BCR-2G	 Spot	 	2	 BCR-2G	 Spot	 	3	 NIST	610	 Linear	 	3	 NIST	610	 Linear	 	3	 BCR-2G	 Linear	 	3	 BCR-2G	 Linear	 	3	 SLCX	45	 Linear	 2	Cpx,	1	Ol	3	 SLCX	21	 Linear	 1	Cpx,	1	Gt	3	 SLCX	11	 Linear	 2	Cpx,	1	Opx,	2	Gt,	2	Ol	3	 NIST	610	 Linear	 	3	 NIST	610	 Linear	 	3	 BCR-2G	 Linear	 	3	 BCR-2G	 Linear	 	*One clinopyroxene, one orthopyroxene and one garnet from the SLCX 12 were ablated under a spot laser mode due to the small size. 	 18	 Duplicate analyses of USGS glass standard BCR-2G (Table 2.5) were made in order to estimate precision and accuracy. The precision is reported as %RSD and the accuracy is reported as MPE%. Concentration data, except As, were calibrated using values from Jochum et al. (2005). Concentrations in BCR-2G, which was treated as unknown, agree well with the recommended values. Precision for Sc, Ti, V, Mn, Co, Zn, Rb, Sr, Y, Zr, Nb, Ba, La, Ce, Pr, Nd, Eu, Tb, Ho, Hf, Ta, and U is better than 5 %; 5 %-10 % for Cu, Cs, Sm, Gd, Dy, Er, Yb, Pb, and Th; 10 %-20 % for others. Cr has a large variation in precision (> 20 %). Accuracy for the majority of detected elements is better than ± 2.5 %, except for Cr, which has low abundances in BCR-2G. Although NIST SRM 610 (Jochum et al., 2011) is used as an external standard, estimates of precision and accuracy using it produce similar numbers for all elements (except for Cr) compared to BCR-2G.     	 19	Table 5 Analyses of BCR-2G    Section1     Section2     Section3        Mean MPE %RSD Mean MPE %RSD Mean MPE %RSD Recommend Sc 32.9  -0.14 2.99 33.2  0.76 5.42 33.2  0.52 3.04 33 Ti 1.41E+4 -0.20 2.40 1.41E+4 0.11 2.87 1.41E+4 -0.04 2.79 14100 V 425  0.11 2.49 426  0.35 3.26 425  0.12 2.86 425 Cr 18.6  11.76 23.10 16.7  0.59 24.02 19.1  15.74 29.77 17 Mn 1.55E+3 -0.16 2.34 1.55E+3 -0.19 2.50 1.55E+3 0.02 2.42 1550 Co 38.1  0.26 0.57 38.1  0.26 3.14 38.0  -0.07 1.73 38 Ni 13.2  1.54 10.16 13.0  0.00 6.75 13.2  2.12 10.00 13 Cu 21.4  2.02 7.92 21.6  3.10 8.23 21.6  3.12 8.00 21 Zn 126  1.16 4.09 125  0.16 5.23 125  -0.22 1.28 125 As 469    188    543     Rb 47.0  0.11 1.37 46.9  -0.21 2.73 47.1  0.16 2.41 47 Sr 342  -0.02 2.77 337  -1.31 4.00 341  -0.17 2.86 342 Y 35.0  -0.02 3.39 34.4  -1.36 7.78 34.9  -0.29 3.94 35 Zr 183  -0.34 2.82 185  0.50 4.26 184  -0.05 3.20 184 Nb 12.5  -0.36 3.10 12.5  -0.08 2.19 12.7  1.50 4.16 12.5 Sb 0.357  2.43 10.52 0.238  -32.14 200.00 0.374  8.07 17.14 0.35 Cs 1.18  2.26 6.37 1.16  0.00 1.86 1.16  0.32 2.82 1.16 Ba 684  0.22 2.76 687  0.62 3.74 684  0.22 3.48 683 La 24.6  -0.39 3.38 24.8  0.30 2.69 24.7  0.08 3.41 24.7 Ce 52.8  -0.94 4.01 53.5  0.52 4.18 53.2  -0.09 2.91 53.3 Pr 6.73  0.49 4.42 6.74  0.75 7.32 6.71  0.26 3.81 6.7 Nd 28.8  -0.30 4.76 28.9  0.09 5.02 28.9  0.09 4.18 28.9 Sm 6.58  -0.04 5.42 6.58  0.53 12.97 6.59  -0.04 0.23 6.59 Eu 1.98  0.51 2.51 2.00  2.41 14.98 1.98  0.63 4.52 1.97 Gd 6.66  -0.48 7.45 6.76  0.97 8.66 6.71  0.04 4.35 6.71 Tb 1.02  0.15 3.67 1.01  0.00 11.74 1.02  0.29 2.92 1.02 Dy 6.48  0.85 6.89 6.49  1.67 15.42 6.44  0.00 0.63 6.44 Ho 1.27  0.00 4.86 1.29  2.17 13.48 1.29  1.36 4.01 1.27 Er 3.71  0.47 5.71 3.71  0.74 10.46 3.71  0.27 1.80 3.70 Yb 3.39  0.00 5.40 3.39  0.07 5.00 3.38  -0.29 4.13 3.39 Lu 0.508  1.54 11.35 0.515  5.86 29.84 0.51  2.24 9.08 0.50 Hf 4.84  -0.05 1.91 4.83  0.00 8.00 4.89  1.29 8.87 4.84 Ta 0.782  0.35 4.56 0.785  1.28 13.28 0.781  0.16 1.99 0.78 Pb 11.0  0.16 5.08 11.0  0.41 4.89 11.0  0.25 1.48 11 Th 5.87  -0.34 5.95 5.88  -0.08 8.02 5.91  0.17 2.38 5.9 U 1.70  0.74 3.34 1.69  0.15 1.01 1.70  0.89 5.35 1.69  	 20	* MPE% = mean percent error = !"" %!  * !"#$%&"' (!)!!"#$%%"&'!"#$%%"&'!!!! , where n = total number of measurements = 4, t = number of measurement, measured values are given in Appendix. %RSD = relative standard deviation = !"# !"#$%& !"#$%#&% !"#$%&$'(!"#$%& !"#$  *100 %. Recommend BCR-2G values are from Jochum et al., (2005).  3.4 Zircon Dating and Trace Element Concentration Profiling  Zircon U-Th/Pb isotopic and trace element data were acquired simultaneously at the University of California, Santa Barbara using a Photon Machines 193 nm ArF Excimer laser ablation system connected via split stream to a multi-collector Nu Plasma (U-Th-Pb data) and an Agilent 7700S Quadrupole (trace element data) inductively-coupled plasma mass spectrometer. Analytical procedures are outlined in (Cottle et al., 2013; Kylander-Clark et al., 2013) with modifications described in (McKinney et al., 2015). Data were collected over a single analytical session with the laser operated at a spot size of 24 µm, 2 Hz frequency, a laser energy of 100 % of 3 mJ (equating to a fluence of ~ 1.5 J/cm2) and 160 shots per analysis that produced pit depths of ~ 12 um. U-Th/Pb age and trace element concentration data reduction, including corrections for baseline, instrumental drift, mass bias, down-hole fractionation and uncorrected age calculations were carried out using Igor Pro and the plugin Iolite v. 2.5 (see Paton et al. (2010) for details on data reduction methodology).   	 21	 A primary reference zircon '91500' (1065 Ma Pb/U ID-TIMS age, (Wiedenbeck et al., 1995)) was used to monitor and correct for instrument drift, mass bias, and down-hole inter-element fractionation for zircon unknowns. A secondary reference zircon, 'GJ1' (601.86 ± 0.37 Ma, Horstwood et al., (2016) ID-TIMS age) was analyzed concurrently and treated as an unknown to assess accuracy and precision. During the analytical period, repeat analyses of GJ1 gave a weighted mean 206Pb/238U age of 602 ± 2 Ma (MSWD = 1.1, n = 9). Trace element concentrations were normalized to GJ-1 reference zircon using the values of (Liu et al., 2010). Typical uncertainties (2σ) are 5 % for elemental concentrations > 1 ppm. All uncertainties for the age data are quoted at 2σ and include contributions from the reproducibility of the reference materials for 207Pb/206Pb, 206Pb/238U and 207Pb/235U.   	 22	CHAPTER Ⅳ  RESULTS 4.1 Petrography  Seven samples from the Salt Lake Crater Xenolith suite were examined in detail. Among all samples, clinopyroxene (Cpx) was the dominant phase, which gave these ultramafic rocks the name pyroxenite. Orthopyroxene (Opx) was observed in five samples, and is often present as the second dominant phase. Garnet (Gt) was widely present in all samples but could only be identified in SLCX 45 using back scatter images and EDS/EMP analyses. Olivine (Ol), though present in four samples, was not an abundant constituent (< 5% in most of slides). Spinel (Sp) and other accessory minerals only had minor modal percentages.   Due to the large crystal size of clinopyroxenes (up to 25 mm), it was difficult to accurately estimate the modal proportion for each phase because the estimated value from thin section may not reflect the actual phase distribution in coarse grained rock samples. A summary of the mineral mode and assemblages in samples is listed in Table 4.1. In the following sample/mineral descriptions, abbreviations are defined as follows: PPL = plane polarized light, XPL = cross- polarized light, RL = reflected light and EBS = electron back scatter image. Text below provides 	 23	detailed mineralogy and textures in the seven samples examined, with emphasis on the two samples (SLCX 12 and SLCX 47) that yielded zircons. Groups are divided based on petrographic features. Representative images of all samples appear in Figure 4.  Overall, the samples share similar granular texture (Figure 4 a, f), with extensive fluid inclusions in clinopyroxene and olivine (Figure 4 b). Most of mineral grains, especially large ones, are highly fractured. Clinopyroxene and olivine are usually present as primary phases. In contrast, orthopyroxene and garnet have bimodal sizes: euhedral to subhedral larger grains and anhedral smaller grains (Figure 4 d, e). The later are more likely to have formed later because they occur as blebs in primary phases or fill interstitial spaces between clinopyroxenes. Locally Clinopyroxenes show triple-junction grain boundaries (Figure 4 c). Spinel tends to occur in the core of euhedral garnet grains, though it is also present within clinopyroxene grains. Sulphide phases are locally present in all seven samples.  24 Table 6 Petrographic Features of Seven SLC Samples Sample Minerals Size & Shape Texture SLCX 11 75 % Cpx + 1 % Opx + 14 % Gt + 10 % Ol Cpx ≤ 3 mm,subhedral to anhedral Ol included in Gt   Opx ≤ 0.5 mm, anhedral Opx included in Ol   Gt ≤ 2 mm, subhedral Cpx included in Ol   Ol ≤ 2 mm, subhedral  SLCX 12 (yields zircon) 60 % Cpx + 30 % Opx + 10 % Gt Cpx ≤ 5 mm,subhedral Opx have bimodal sizes   Opx ≤ 3 mm, subhedral Opx blebs in Cpx  Gt ≤ 2 mm, anhedral  SLCX 21 67 % Cpx + 5 % Opx + 25 % Gt + 3 % Spl Cpx ≤ 25 mm, euhedral to subhedral Opx blebs in Cpx   Opx ≤ 0.5 mm, anhedral extensive presence of fluid inclusions   Gt ≤ 5 mm, subhedral Sp occuring as core of Gt   Spl ≤ 2 mm, anhedral  SLCX 25 50 % Cpx + 30 % Opx + 10 % Gt + 10 % Ol Cpx ≤ 3 mm,subhedral Ol&Gt form corona around Opx   Opx ≤ 1.5 mm, euhedral triple junction   Gt ≤ 0.5 mm, anbhedral    Ol ≤ 0. 5mm, anbhedral  SLCX 26 60 % Cpx + 10 % Opx + 25 % Gt + 5 % Spl Cpx ≤ 10 mm,subhedral Sp occuring as core of Gt   Opx ≤ 6 mm, euhedral to subhedral   Gt ≤ 5 mm, eubhedral    Spl ≤ 1.5 mm, anhedral  SLCX 45 65 % Cpx + 30 % Gt + 5 % Ol Cpx ≤ 4 mm,subhedral Cpx have bimodal sizes   Gt ≤ 0.3 mm, subhedral    Ol ≤ 0.5 mm, anbhedral  SLCX 47 (yields zircon) 60 % Cpx + 25 % Gt + 15 % Ol Cpx ≤ 3 mm,subhedral Cpx&Gt locally included in Ol   Gt ≤ 6 mm, euhedral to subhedral   Ol ≤ 5.5 mm, euhedral to subhedral 	 25	* Modal percentages are approximate; they were determined by visual estimation. However, since the rock is coarse grained and phases can occur in clusters, the estimated modal percentages from thin sections may not represent the true modal percentages in samples.        Figure 4 Plane polarized photomicrographs of representative mineral assemblages and textures. (a) Granular texture (b) fluid inclusions in Cpx (c) a triple junction (d) an anhedral garnet filling interstitial space (e) orthopyroxene exsolution blebs in a clinopyxene (f) an olivine enclosed by garnet and clinopyroxene    A volatile-rich, nearly opaque, high relief phase is common in SLCX 47. Locally, it occurs in olivine cores, but more commonly, it forms granular crystals in contact with clinopyroxene or 	 26	garnet (Figure 5 a). Under reflected light, the phase seems composed of two components, one is in dark colour and the other in light colour.     Figure 5 Photograph of the unknown phase. (a) under reflected light (b) back scattered electron image (c) under the electron microscope.    	 27	Table 7 SEM-EDX Composition of the Unknown Phase Element wt% SD O 45.79 0.08 Na 1.75 0.22 Al 13.93 0.06 Si 25.55 0.09 Cl 0.34 0.14 K 6.00 0.06 Ca 5.74 0.14 Fe 0.30 0.08 Ba 0.60 0.1 Total 100  *Element concentrations are reported in weight percent (wt%). SD stands for standard deviation for three analyses. Results were normalized to 100 % and are semi quantitative.   4.2 Elemental Mapping     In samples SLCX 26 and SLCX 21, large garnets generally have a spinel core (Figure 6). Back-scatter images and wave-length dispersive maps show that the garnet is homogeneous in terms of Fe, Mg, Ca, Si and Mn. Mg concentrations are the same in garnet and spinel but the latter shows lower Ca, Si, Mn and higher Fe. At the edge of the garnet, high Mg# anhedral olivines form a corona, and are enclosed in clinopyroxenes.  	 28	 Figure 6 Back Scattered Electron Image and elemental maps of SLCX 26 garnet. The map reveals a spinel-garnet-olivine-clinopyroxene complex.  4.3 Major Element Mineral Analyses  Fiftty one grains of clinopyroxene, orthopyroxene, garnet and olivine were selected for analysis from seven samples with three analyses on each grain for major element concentrations. 	 29	The data (Tables B.1-B.4) are average compositions for each individual grain where there was restricted chemical variation.  4.3.1 Clinopyroxene  Clinopyroxene (Cpx) is the dominant phase in all seven samples. Compositions are restricted to the diopside and augite fields (Figure 7). Although clinopyroxene sizes show a bimodal distribution, the small, anhedral grains exhibit little chemical variation from large, subhedral ones. The low Cr2O3 (< 0.5 wt%), high Al2O3 (6.0 wt%-8.3 wt%) and high FeO (5.3 wt%-8.3 wt%) characteristics are consistent with those reported in the literature for other SLC garnet pyroxenite xenoliths (Bizimis et al., 2005; Keshav et al., 2007).   The Mg# of most clinopyroxenes is between 78 and 83, but those in SLCX 21 have values between 72 and 73 (Figure 8). Mg# shows a systematic relationship to FeO, but correlation with other oxides are more scattered. Analyses form four clusters (SLCX 21, SLCX 45, SLCX 12 and SLCX 11 + 25 + 26 + 47), but all samples appear subtly distinct. Sample SLCX 21 clinopyroxenes are most distinct with low Si and high Ti, Al, Fe, Na contents.  	 30	               Figure 7 Compositions of SLCX clinopyroxenes and orthopyroxenes. Samples are plotted on a wollastonite (Wo), enstatite (En) and ferrosilite (Fs) classification diagram. 	 31	     Figure 8 Plots of Mg# versus major element oxides for clinopyroxenes.  	 32	4.3.2 Orthopyroxene  Orthopyroxene (Opx) found in four samples is Enstatitic (Figure 7) and has high Al2O3 (4.0 wt%-5.6 wt%), consistent with analyses reported in the literature (Bizimis et al., 2005; Keshav et al., 2007; Sen, 1988). Mg# varies from 79 to 82, with low values associated with FeO ≤ 13.1 wt%. Based on Mg# (Figure 9), the analyses form two clusters, but the clusters are not sample dependent. For example, the low Mg# cluster contains one SLCX 11 and two SLCX 25 analyses. Analyzed orthopyrxoenes from the same sample are not chemically homogenous, and this heterogeneity has also been reported in the literature (Keshav et al., 2007; Sen, 1988). Considering the major element composition data together with petrography, it turns out that orthopyroxenes with low Mg# are usually enclosed by olivines, but high Mg# Opx is an exsolution phase in clinopyroxene, or forms small, granular, anhedral crystals.  	 33	 Figure 9 Plots of Mg# versus major element oxides for orthopyroxenes. 	 34	4.3.3 Garnet  Both large subhedral, and small anhedral garnets in the samples are chemically unzoned. The Mg# varies from 60.3 to 69.5, which overlies SLC garnet pyroxenite reported in the literature (Bizimis et al., 2005; Keshav et al., 2007; Sen, 1988). Although all garnets are pyropes (Figure 10), analyses form two clusters: one is the SLCX 21 garnets and the other comprises garnets from the rest of the samples.   Garnets with spinel cores in SLCX 21 have higher FeO and lower MgO contents. They resemble garnets exsolved from clinopyrxoene reported by Keshav and Sen, (2003). The authors argued that garnet exsolusion was triggered by the addition of kimberlitic melts to the primary olivine-bearing pyroxenite. The extensive presence of fluid inclusions in SLCX 21 supports that hypothesis. Although garnets from both SLCX 21 and SLCX 26 developed spinel cores, garnets from SLCX 26 have similar compositions to garnets from spinel-absent samples.   	 35	             Figure 10 Ternary diagram of garnet compositions. End-members are pyrope (Prp), almandine (Alm) and grossular (Grs).  4.3.4 Olivine  Olivines from any single xenolith have equivalent fosterite (Fo) contents, but between samples they vary from Fo77 to Fo82, values similar to those reported in the literature (Keshav et al., 2007; Sen and Jones, 1990). The anhedral small olivines from SLCX 45 are distinct and have the highest Fo content (Fo82). The concentrations of Cr2O3 are below 0.02 wt% and NiO varies from 0.27 to 0.37 wt%.  	 36	4.4 Trace Elements  Trace element concentrations were measured on clinopyroxenes, orthopyroxenes, garnets and olivines, but only clinopyroxenes and garnets provide useable REE data, because orthopyroxenes and olivines have concentrations typically below detection limits. Thus, this section only presents clinopyroxene and garnet trace element data. Data appear in Table B.5 and B.6.   4.4.1 Clinopyroxene  Figure 11 shows clinopyroxene compositions on a primitive mantle (McDonough & Sun, 1995) normalized diagram. The data reported here are largely identical to those for Salt Lake Crater pyroxenite xenolith clinopyroxenes reported by Bizimis et al. (2005), suggesting that they are from the same sample group. An exception is that Ba in SLCX 12-Cpx1 and SLCX 25-Cpx3 is much higher, and Lu in SLCX 47-Cpx3 appears much lower than in the primitive mantle. Three samples have clinopyroxene with high Pb abundances, and two of them (SLCX 12 and SLCX 47) yielded zircons. High Ba could be due to sampling Ba-enriched fluid inclusions during laser ablation. High Pb in SLCX 11, 12 and 47 clinopyroxene may be due to dissolution 	 37	of ancient zircons, release of radioactive Pb, and growth of new clinopyroxene (see details in Discussion).   The Light Rare Earth Element (LREE) and Middle Rare Earth Element (MREE) abundances in clinopyroxene can be almost an order of magnitude higher than in primative mantle (Figure 11). The Heavy Rare Earth Elements (HREE) are depleted, and Bizimis et al. (2005) suggested that this is due to the presence of coexisting garnets, which are highly HREE compatible. The High Field Strength Elements (HFSE; e.g. Nb, Zr) and Large Ion Lithophile Elements (LILE; e.g. Ba) are generally depleted compared to the adjacent REE. This HFSE depletion feature has also been reported in pyroxenite xenoliths recovered from Hannuoba, North Chia Craton (Xu, 2002). Note that in Xu's paper, the REE trend is nearly identical to our result. HFSE depletion in pyroxenite clinopyroxene may be a chemical fingerprint for subcontinental lithospheric mantle. 	 38	 Figure 11 Primitive mantle normalized trace element abundances in SLC clinopyroxenes. The grey field data are for similar SLC rocks studied by Bizimis et al. (2005). Primitive mantle normalizing values are from McDonough & Sun (1995).   Figure 12 reveals Mg# vs. compatible/incompatible elements plots. It appears that for clinopyroxenes, the Mg# does not have a linear correlation with either compatible elements (Sc, Ni) or incompatible elements (Sr, Nb). This observation is consistent with the argument given by Bizimis et al. (2005), in which they suggested the change in clinopyroxene composition is not associated with increasing degrees of melting.  	 39	 Figure 12 Mg# vs. compatible elements (Sc, Ni) and incompatible elements (Sr, Nb) in clinopyroxenes. The element concentrations were normalized by primitive mantle values from McDonough & Sun (1995). 4.4.2 Garnets  All garnets except SLCX 26-Gt1 and SLCX 47-Gt3 display negative Hf anomalies on a primitive mantle normalized diagram (Figure 13). Pb abundances in our samples are ~10x higher than the average values reported by Bizimis et al. (2005), though two of his samples (601 and 714) gave similar high Pb abundances. 	 40	 Figure 13 Primitive mantle normalized trace element abundances in SLC garnets. The grey field data are average trace element concentrations for similar SLC rocks studied by Bizimis et al. (2005). Primitive mantle normalizing values are from McDonough & Sun (1995).  4.5 Zircon Petrochronological Signatures 4.5.1 Morphology and texture of zircons  The four dated zircons (Zircon1, Zircon2 from SLCX 47; Zircon3, Zircon4 from SLCX 12) are euhedral, tabular to prismatic and show tetragonal dipyramidal forms (Figure 3), indicating a magmatic or high-grade metamorphic origin (Hoskin & Schaltegger, 2003). The LA-ICP-MS 	 41	depth profiling data (Table B.7-B.12) especially for Zircon1 and Zircon3 indicate the presence of zoned cores, with relatively homogeneous overgrowth rims.   4.5.2 Zircon1 Age and Trace Element Data  Zircon1 is characterized by continuously increasing ages from the rim (~ 13 Ma) to the core (~ 82 Ma) (Figure 14). The average rim gives an age of 13.4 ± 0.2 Ma (2SE), based on data obtained from depths between 0 and 10 µm (Table 4.3). The oldest age, 82.2 Ma, was measured at a depth of 12.05 µm. An average of 76.9 Ma was obtained from analyses between ~ 11.85 µm and 12.15 µm depth. Because the ages given by the core did not form 'plateau' (unlike Zircon3), the 76.9 Ma age represents a minimum date for the core.  Table 8 Summary of Ages of Four Zircons   Age (Ma) Depth (µm) Zircon1 (SLCX 47) 13.4 ± 0.2 (rim) 0-10   76.9 (core) 11.85-12.15   Zircon2 (SLCX 47) 14.5 ± 0.2  0-11.5  Zircon3 (SLCX 12) 12.9 ± 0.2 (rim) 0-6.25  80.8 ± 2 (core) 10-11.25  Zircon4 (SLCX 12) 14.2 ± 0.3   0-12.25 *Plots involving zircon trace element concentrations data from depth ranges that coincide with ages in the table.  	 42	 Figure 14 Chondrite-normalized Hf, Y and U concentrations and age profiling data for Zircon1. Chondrite normalizing values are from McDonough & Sun (1995).  Hf is enriched in the zircon, with an average concentration of 9457 ppm (Figure 14). The highest value, 16582 ppm, occurs in the rim, and the lowest, 106 ppm, occurs in the core (Figure 14). Although the Hf abundance shows great variability between the rim and core, the rim (0-10 µm) shows a relatively homogeneous Hf concentration. The overall enriched pattern resembles zircons extracted from mafic rocks, but the 106 ppm given by the core is lower than zircons derived from any known tectonic setting (Belousova et al., 2002). Similar to Hf, Y is enriched in magmatic zircons (Belousova et al., 2002; Grimes et al., 2015; Hoskin and Ireland, 2000),with 	 43	abundances up to 8500 ppm (Guo et al., 1996). The Y abundance of Zircon1 ranges from 1070 ppm (core) to 3676 ppm (rim), which is typical of magmatic zircons, but distinct from mantle-derived zircons found in kimberlites (Belousova et al., 1998; Hoskin and Ireland, 2000), which usually have Y below 100 ppm.    Figure 15 shows average chondrite-normalized REE patterns for the rim and the core of Zircon1, with data collected from 0.28 µm to 9.95 µm representing the rim, and 11.88 µm to 12.16 µm representing the core. Ages indicated on the diagram are average U-Pb dates given by the above depths.  The overall chondrite-normalize REE patterns (Figure 15) show HREE (Tb to Lu) enrichment, with La and Pr below the detection limit. Cerium, which can be both trivalent and tetravalent, tends to be more compatible in zircons than La and Pr (Hoskin & Ireland, 2000). Abundances in Zircon1 vary from 0.7 ppm (rim) to 18.3 ppm (core), which is within the range of zircons from various tectonic settings (Belousova et al., 2002). The MREE (Nd to Gd) show increasing chondrite-normalized abundances with decreasing ionic radii, except there is a negative Eu anomaly. The HREE are more abundant than the LREE and MREE with 	 44	concentrations between 103 and 104× chondrite. Although Lu has a radius more comparable to Zr, the most abundant element is Yb, ranging from 1235 ppm in the rim to 14 ppm in the core.        Figure 15 Chondrite-normalized REE patterns for Zircon1. Chondrite normalizing values are from McDonough & Sun (1995).   Overall, both trends have steep positive LREE to HREE slopes (Figure 15), but the rim is more enriched in HREE and depleted in LREE. The core has a normalized Ce value higher than Nd, indicating a potentially large positive Ce anomaly in the core, and a possible smaller anomaly for the rim. A large positive Ce anomaly is a feature of zircons with a magmatic origin, and it is believed to reflect oxidizing conditions (Grimes et al., 2015; Hoskin and Schaltegger, 2003; Liu et al., 2010). Zircons lacking Ce anomalies have only been found in meteorites, lunar 	 45	rocks and kimberlites (Belousova et al., 1998; Ireland and Wlotzka, 1992), which are expected to have crystallized under reducing conditions.  4.5.3 Zircon2 Age and Trace Element Data  Dates from Zircon2 form one cluster (Figure 16), with an average age of 14.5 ± 0.2 Ma (2SE) measured between 0 and 11.5 µm, which is comparable to the rim zone of Zircon1. An anomalous age (50.4 Ma) at a depth of 10.1 µm was ignored in calculating the average age. An old core was not discovered.  	 46	 Figure 16 Chondrite-normalized Hf, Y and U concentrations and age profiling data for Zircon 2. Chondrite normalizing values are from McDonough & Sun (1995).  The average Hf content is 10564 ppm, with the highest value of 17163 ppm in the rim and the lowest value of 8049 ppm occurring at the depth of 8.29 µm (Figure 16). These values resemble the Hf enriched rim of Zircon1. The Y contents range from 1289 ppm to 3679 ppm, which is comparable to Zircon1. The∑REE ranges from 852 ppm to 2457 ppm, with an average of 1466 ppm, which is comparable to the rim zone for Zircon1.   The average chondrite-normalized REE diagram (data collected from 0.28 µm to 11.6 µm) shows a steep, positive, chondrite-normalized REE pattern with a distinct negative Eu anomaly. 	 47	The pattern resembles the rim of Zircon1 but lacks a positive Ce anomaly. The LREE are extremely depleted (Figure 17), and both La and Pr fall below the detection limit. The abundance of Ce is comparable to the rim of Zircon1. The MREE, similar to Zircon1, show increasing abundances from Nd to Gd, and a negative Eu anomaly. The HREE are enriched, and the most abundant element is Yb, ranging from 322 ppm to 1053 ppm.    Figure 17 Chondrite-normalized REE pattern for Zircon2. Chondrite normalizing values are from McDonough & Sun (1995). 	 48	4.5.4 Zircon3 Age and Trace Element Data  Zircon3 has ages increasing toward the core (Figure 18). The rim (0 to 6.25 µm) gives an average age of 12.9 ± 0.2 Ma (2SE). The core (10 µm to 11.25 µm), unlike Zircon1, shows an 'age plateau' with an average age of 80.8 ± 2 Ma (2SE).   Figure 18 Chondrite-normalized Hf, Y and U concentrations and age profiling data for Zircon3. Chondrite normalizing values are from McDonough & Sun (1995).  Hafnium abundances are similar to Zircon1, with large variability between the young rim and the old core. Concentrations range from 16899 ppm (rim) to 311 ppm (core), with an average of 10702 ppm. Similarities to Zircon1 indicate that although the two zircons occur in 	 49	different samples, they could form from similar melts. The Y abundances in Zircon3 range from 1166 ppm to 3762 ppm, with an average of 1806 ppm. These values are comparable to Zircon1, but are much higher than in kimberlitic zircons. The ∑REE ranges from only 127 ppm in the core to 2182 ppm in the rim, with an average concentration of 1561 ppm, and a peak concentration (1934 ppm-2182 ppm) between 6.91 µm and 8.29 µm. This pattern of relative enrichment/depletion with depth is not identical to that in Zircon1.  Overall, the chondrite- normalized REE pattern and REE concentrations for Zircon3 resemble Zircon1 (Figure 19). Similar to Zircon1 and 2, La and Pr are below the detection limit. Cerium increases with depth, reaching a peak of 105 ppm at 10.77 µm, a concentration much higher than in the Zircon1's core. In the rim, the MREE show a U-shaped chondrite-normalized pattern. The rim trend of Zircon3 is distinguished from Zircon1 by the absence of a negative Eu anomaly,  	 50	      Figure 19 Chondrite-normalized REE patterns for Zircon3. Chondrite normalizing values are from McDonough & Sun (1995).  4.5.5 Zircon4 Age and Trace Element Data  The age given by Zircon4 is 14.2 ± 0.3 (2SE) Ma, which is an average age from U/Pb dates obtained between 0 µm and 12.25 µm (Figure 20). This age is comparable to the age of Zircon2, and is older than the rim of Zircon1 and 3, but between 11.9 µm and 12.25 µm ages are older (~ 20 Ma). Furthermore, ~ 20 Ma ages appear several times through the rim. This may be because the laser had partly sampled a portion of the zircon that is older. 	 51	 Figure 20 Chondrite-normalized Hf, Y and U concentrations and age profiling data for Zircon4. Chondrite normalizing values are from McDonough & Sun (1995).  The Hf abundance varies from 660 ppm in the inner core (12.16 µm) to 14429 ppm for the rim, with an average of 10074 ppm. Overall, Hf increases from the core to the rim. The Hf abundance shown by this zircon is identical to Zircon2, and comparable to the rim of Zircon3. The Y abundances of Zircon4 range from 1099 ppm to 3875 ppm, with an average of 1753 ppm. This value is identical to the other three zircons. The abundance increases from the core towards the rim, and Zircon1, 2 and 4 show a jump in Y at the outer (1-2 µm) edge. The ∑REE averages 	 52	1408 ppm, varying from 123 ppm (core) to 2841 ppm (rim). Variation is more extensive than in Zircon2. Overall, the ∑REE pattern increases in the rim, similar to that seen in Zircon1.   The chondrite-normalized REE plot (Figure 21) is based on average data obtained between 0 and 12.16 µm at depth. Both La and Pr are below the detection limit. The plot shows a steep positive slope. The lack of a positive Ce anomaly and the presence of a negative Eu anomaly resemble Zircon2 and the rim of Zircon1. Note that the Nd content in Zircon4 is higher than in Zircon2.    Figure 21 Chondrite-normalized REE pattern for Zircon4. Chondrite normalizing values are from McDonough & Sun (1995).    	 53	CHAPTER Ⅴ  DISCUSSION 5.1 Genetic Relationships   It is important to investigate whether the seven samples studied here are genetically related (form from a single magma series). Although clinopyroxene and garnet occur in all samples, olivine was not observed in SLCX 12, 21 and 26, and samples SLCX 45 and SLCX 47 lack orthopyroxene. Considering the great variation of grain sizes and mineral assemblages (Table 4.1), it is unlikely that these samples were derived from the exact same location beneath Oahu. The presence of olivine in four samples indicates they may be more primitive than the other three. Possibly the seven samples can be linked by crystal fractionation process.  To assess genetic relationships, one of the most useful tools is variation diagram. Major element variation diagrams for clinopyroxene and orthopyroxene (Figure 8 & 9) reveal that, except for FeO, there is no linear correlation between Mg# and other major element oxides, and most of the plots show considerable scatter. Although patterns for the low-concentration elements (Mn, Cr) could be affected by detection limits, the scattered CaO and Al2O3 plots indicate that the seven samples are not all genetically related. 	 54	              Figure 22 Multi-dimensional scaling comparisons of seven samples based on the overall major, minor and trace element composition of clinopyroxene.   Multi-dimensional scaling (Greenough et al., 2007) is a powerful tool used to uncover relationships within a group of samples. Major, minor and trace element data were used to compare the samples (Figure 22). It appears that there are no clear relationships among the seven samples, though SLCX 21 plots close to SLCX 11, indicating there are no genetic relationships between samples. Each sample has its own distinct geochemical characteristics (Figure 22).   The primitive mantle-normalized trace element patterns for clinopyroxene (Figure 11) reveal that all samples are enriched in LREE, but depleted in HREE. Additionally, similar negative 	 55	anomalies in HFSE (Zr, Nb) and LILE (Ba, Pb) occur in most samples. Such chemical characteristics indicate that the melts parental to the pyroxenites formed in the same petrological and tectonic environment. Neither compatible elements (Ni, Sc) nor incompatible elements (Sr, Nb) are linearly associated with Mg# (Figure 12), indicating that the pyroxenites were not crystallized from a single fractionating melt. 5.2 Origin of SLC Xenoliths  Pyroxenites, which comprise around 5 % of the upper mantle, have been widely discussed in the recent literature (Choi and Kim, 2012; Hirschmann and Stolper, 1996; Hirschmann et al., 2003; Kogiso et al., 2003). Pyroxenites are usually attributed to one of three origins: 1) interaction between mantle peridotite and melt/fluid (Liu et al., 2001; Xu, 2002), 2) segments of recycled oceanic crust (Allègre et al., 1983; Pearson et al., 1993), and 3) cumulates precipitated from melts. Origins of the SLC pyroxenites will be assessed based upon chemical signatures exhibited by analyzed phases.  	 56	5.2.1 Frozen melt   Since the pyroxenite can occur together with peridotite (Bizimis et al., 2004; Sen et al., 1993), the first question to be answered is whether they represent frozen melt derived from partial melting of the peridotite. Incompatible elements (e.g. REE) should be enriched in the melt during partial melting, and if the melt crystallized to form pyroxenite, these trace elements should be concentrated in crystallized phases. In ultramafic rocks, clinopyroxene is the major reservoir for the REE due the comparable ionic radius between Ca2+ and REE3+, and incorporation is enhanced for the HREE (Olin and Wolff, 2010). If the pyroxenites represent frozen peridotite-derived melt, they should hold more ∑REE than the peridotite. The peridotite clinopyroxenes have ∑REE ranging from 21 ppm to 95 ppm, with an average of 42 ppm (Bizimis et al., 2004) , whereas our clinopyroxenes have ∑REE ranging from 25 ppm to 48 ppm, with an average of 35 ppm. It appears that the SLCX pyroxenites are more depleted in incompatible elements than the host peridotite. This observation is in contrast with a frozen melt origin for the pyroxenites. Thus the pyroxenites are unlikely to be partial melts derived from associated peridotite. 	 57	 During partial melting, ratios of elements with similar incompatibility tends to be minimally affected by the degree of melting (Greenough et al., 2007). If the pyroxenites crystallized from a peridotite-derived melt, similarly-incompatible element ratios (E.g. Nd/Sm, Zr/Hf) should be similar for peridotite and pyroxenite. However, it appears that the peridotite ratios are higher and scattered (Figure 23). This, together with the difference in total REE abundances, suggests that the pyroxenites do not represent solidified melt derived from melting of the fertile peridotites, and there is no direct genetic relationship between the two groups of xenoliths.         Figure 23 Zr/Hf vs. Nd/Sm ratios of clinopyroxene in peridotite and pyroxenite from the Salt Lake Crater. Peridotite trace element data were derived from (Bizimis et al., 2004).  	 58	5.2.2 Recycled oceanic crust   The common occurrence of the chlorine-bearing unknown mineral (Figure 5) indicates that the pyroxenite may be related to recycled oceanic crust which absorbed sea water. However, the absence of Al2O3 depletion (< 1 wt%) in orthopyroxene (Figure 9) and the lack of a positive Eu  anomaly in clinopyroxene (Figure 11), are in contrast with a conventional recycled oceanic crust model (Allègre & Turcotte, 1986; Kornprobst et al., 1990; Morishita et al., 2003). This indicates the samples are not recycled/recrystallized fragments of oceanic crust. It is difficult to assess the equilibrium between the chlorine-bearing phase and the other minerals (clinopyroxene, garnet, olivine) because without identifying the mineral, partitioning coefficients cannot be compared to literature data. Detailed research on the origin of this phase is beyond the scope of this study.  5.2.3 Cumulate origin  Previous studies concluded that the pyroxenite xenoliths recovered from the Salt Lake Crater are cumulates crystallized at lower lithosphere or even deeper depths as a result of fractional crystallization (Bizimis et al., 2005; Keshav and Sen, 2003; Keshav et al., 2007). Our trace element data show that these pyroxenites are depleted in incompatible elements, which is a 	 59	feature commonly attributed to cumulate phases from fractional crystallization (Pearson et al., 1993). Thus, our garnet-bearing pyroxenite xenoliths are considered cumulates formed due to fractional crystallization.  5.3 Source Melt and Petrognesis of Clinopyroxene and Garnet 5.3.1 Melt composition  It is widely accepted that the parental melt that crystallized the SLC pyroxenite xenoliths was never erupted at the surface (Bizimis et al., 2005; Keshav and Sen, 2003; Lassiter et al., 2000), though the origin of this melt remains unclear. Sen & Jones (1990) suggested that the parental melt of the xenoliths was similar to Koolau tholeiitic magma. However, recent combined Nd-Sr-Hf isotope data and melt composition modelling indicate that there is no apparent genetic relationship between the Koolau tholeiitic magma and the xenoliths, but the melt was compositionally similar to Honolulu Volcanic series magma (Bizimis et al., 2005).   The trace element composition of melts parental to clinopyroxene have been reconstructed by using the equation Cmelt = Cphase/Dphase/melt, where Cmelt represents the concentration of a trace element in the melt, Cphase represents the element's concentration in a rock forming phase 	 60	(clinopyroxene), and Dphase/melt represents the phase/melt partitioning coefficients for each element. Cpx-Gt D values have been experimentally determined for basalt under high temperature-pressure conditions (Hauri et al., 1994).   Figure 24 Primitive mantle-normalized trace element composition of melts in equilibrium with clinopyroxene. Partitioning coefficients were from (Hauri et al., 1994). Composition of the primitive mantle is from (McDonough and Sun, 1995). HV data are an average of Honolulu Series volcanic rocks derived by Clague & Frey (1982).  Overall, the parental melts of the clinopyroxene are comparable to the Honolulu Series (Clague & Frey, 1982) with a negative slope from Th to Yb, and absence of an Eu anomaly (Figure 24). However, parental clinopyroxene melts distinguish themselves from the HV lava by showing a strong positive Pb anomaly, subtle positive Hf anomaly and depletion in Yb. The 	 61	strong lead anomaly is a signature that can be correlated to Archean age subcontinental lithospheric mantle, and this will be discussed in detail in the next section (Hoffmann 2008).   The equilibrium between clinopyroxene and garnet has been evaluated by comparing calculated Cpx/Gt partitioning coefficients for REE (Figure 25) with values from (Harte & Kirkley, 1997). The calculated partitioning coefficients show considerable similarities to values from the literature, with a negative slope from Ce to Yb, indicating clinopyroxenes are in equilibrium with garnets. This indicates that the inference drawn from the Cpx-equilibrated melt composition could also be applied to garnets.           	 62	Figure 25 Cpx/Gt partitioning coefficients for REE. Data presented are average partitioning coefficients in SLCX 47 and SLCX 12. Values from (Harte & Kirkley, 1997) are used for comparison.  5.3.2 Pb enrichment and association with subcontinental lithospheric mantle  Lead is a key element for understanding the evolution of the mantle and continental crust (Hoffmann 2008) and may provide useful information on the tectonic environment of formation of the SLCX pyroxenite xenoliths. The calculated melt composition is characterized by anomalous enrichment in Pb, which is a signature commonly observed in xenoliths derived from the Archean subcontinental lithospheric mantle (SCLM) (Arndt et al., 2009; Aulbach et al., 2007; Aulbach, 2012). Greenough & Kyser (2003) suggested that the recycling of oceanic crust/lithosphere during ancient continent formation could result in significant Pb accumulation in the SCLM, which could be subsequently sampled by xenoliths or continental flood basalts. Therefore the parent melt of SLCX could have a SCLM origin. If a fragment of ancient SCLM was detached and then entrained in the oceanic lithospheric mantle, melting of this reservoir could produce magma with Pb enrichment as observed in our samples. Therefore, it is inferred that the Pb enrichment reflects derivation from a SCLM-related source.   	 63	5.3.3 Local Pb anomaly in Cpx  Like Bizimis et al. (2005) found, clinopyroxenes reported here generally show negative, Pb, primitive-mantle-normalized trace element patterns (Fig. 4.8). However, in both this study and in Bizimis et al. (2005) a few analyses show positive anomalies, and this study demonstrates that Cpxs can show both positive and negative Pb anomalies in a single sample (SLCX 11, SLCX 12, SLCX 47). This mm-scale variation in Pb is challenging to explain. One possibility is that the Cpxs were formed by different processes (igneous, metamorphic, metasomatic) but this does not explain why they are so similar, except for Pb. Lead variation may be due to randomly-distributed, micron-scale, Pb-hosting sulphide grains in Cpx, randomly sampled by the laser. This explanation appears unlikely because Pb spikes were not observed during processing of the LA-ICP-QMS signals.   Lead concentrations were determined using 208Pb. Nucleosynthetic processes that produced the solar nebula supplied 208Pb to Earth (Hoffmann 2008), but the decay of 232Th, with a long half-life of 1.405×1010 years, has added 208Pb too. Zircons tend to incorporate 232Th into their structure and therefore ancient zircons bear abundant 208Pb (Hoskin & Schaltegger, 2003). If an 	 64	ancient zircon dissolved, it would produce high local Pb concentrations. An explanation for the positive Pb anomalies in a few Cpxs could be that during crystallization, they incorporated Th-derived Pb locally from dissolved zircons. This explanation also supports the hypothesis that the parent melts that formed SLC xenoliths could be derived from an ancient source.  5.4 Significance of Zircon Ages 5.4.1 Zircon Associated Mineral  In order to assess the significance of the zircon ages, it is important to know which minerals formed in equilibrium with zircon cores and outer rims. The zircons were extracted by whole rock processing, and textural relations with other minerals were lost. Similarly, zircons were not observed in thin sections. Zircon/mineral partitioning coefficient can help provide information on the relationship between zircon and other phases.    Since Clinopyroxene is the dominant and 'primary' phase in all SLC pyroxenites (Bizimis et al., 2005; Keshav et al., 2007), there is a good chance that it formed together with the zircons. The partition coefficient D, defined as a ratio D = Cphase1/Cphase2, can be used to evaluate equilibrium. Cphase1 is the concentration of an element in phase 1, and Cphase2 is the concentration 	 65	of in phase 2. If calculated zircon/clinopyroxene D values are the same or similar to experimentally determined values in the literature, it can be assumed that clinopyroxenes formed in equilibrium with the zircons.    Dzircon/Cpx values were calculated from experimentally determined Dzircon/melt (Lesnov, 2013) and DCpx/melt (Sun & Liang) values using the following equation: Dzircon/Cpx = Dzircon/melt/DCpx/melt. The Dzircon/melt and DCpx/melt values are listed in Table 5.1. Temperature, mineral composition and melt composition are the dominant factors affecting partition coefficients (Green et al., 1989; Guay, 2007; Lesnov, 2013; Rubatto and Hermann, 2007; Sun and Liang, 2011; Taylor et al., 2015; Yao et al., 2012). Our samples were crystallized at temperatures of ~ 1300 ℃ (Bizimis et al., 2005; Keshav et al., 2007), similar to the conditions under which partitioning coefficient in the literature were determined. Melts in both experiments (Lesnov, 2013; Sun and Liang, 2011) are basaltic melts with similar compositions. The Al2O3 concentration in clinopyroxene, which is the major factor influencing REE partitioning between clinopyroxene and zircon (Sun & Liang, 2011), shows similar values (~ 7 wt%) in our samples and in the literature.    	 66	Table 9 Partition Coefficients from the Literature Used to Construct the Reference Line in Figure 26 REE Dzircon/melt (Lesnov, 2013) DCpx/melt (Sun &Liang, 2011) Dzircon/Cpx Ce 0.022 0.108 0.20 Nd 0.176 0.277 1.03 Sm 1.06 0.462 2.29 Eu 2.3 0.458 5.02 Gd 5.01 0.446 11.23 Tb 10.9 0.497 21.94 Dy 23.7 0.538 44.04 Ho 48.6 0.566 85.91 Er 94 0.581 161.90 Yb 293 0.582 503.52 Lu 472 0.573 823.30 * Dzircon/melt are from Table 12 in (Lesnov, 2013). DCpx/melt are from Table 3 in (Sun and Liang, 2011).  Compared with literature Dzircon/Cpx values for REE (Figure 26), which represents ideal REE partition coefficients between zircon and clinopyroxene under similar conditions, SLCX Dzircon/Cpx values are similar. For both zircon-bearing samples, Dzircon/cpx values for the zircon core and rim domains are very similar: both show a steep positive slope. This trend is consistent with the fact that, compared to the LREE, the HREE are favoured by zircon due to smaller ionic radii. Core Dzircon/Cpx values for Ce are higher than in the rim, reflecting higher Ce in the core. For all other elements, D values are identical for the cores and rims. This implies that the rim domain is genetically related to the core domain.  	 67	           Figure 26 Diagram showing zircon/clinopyroxene partition coefficients for REE in samples SLCX 47 and SLCX 12. Data from (Lesnov, 2013) and (Sun and Liang, 2011) were used to construct the zircon/clinopyroxene D-value reference line.   The similarity between the core and rim, despite forming ~ 65 million years apart, is consistent with the rim forming from dissolution of core zircons, and then reprecipitated, with composition similar to the dissolved zircon. The primary difference between rim and core is 	 68	reflected by the Dzircon/Cpx values for Ce, which are higher in the cores but lower in the rims and unzoned zircons. Unlike other REEs that form 3+ cations, Ce has two oxidation states (3+ and 4+) and under oxidizing conditions Ce4+ can predominantly substitute for Zr4+ in the zircon structure (Trail et al., 2012). Higher Ce in zircon cores is consistent with formation under more-oxidizing conditions, then transferred to less-oxidizing or reducing conditions during formation of the rims. The clinopyroxene and garnet compositions do not provide any trace element evidence for formation at variable fO2, but the rim Dzircon/Cpx values for Ce are closer to the literature-derived reference line (Figure 26). Thus, the clinopyroxenes more likely crystallized/recrystallized during a thermal/geochemical event that formed the zircon rims.   Zircon/Garnet partitioning coefficients for REE were also calculated for comparison with values determined from natural metamorphic rocks (Figure 27). Zircon/garnet partitioning coefficients used in Figure 27 were from Table 3 in Rubatto (2002). The granulites formed at ~ 800 °C, and the protolith is felsic in composition, thus both the temperature of formation and lithology are distinctly different from those for the SLC xenoliths. Therefore, the following inferences, based on Dzircon/ Gt, may not be as reliable as those made based on the Cpxs.     	 69	          Figure 27 Diagram showing zircon/garnet partition coefficients for REE in samples SLCX 47 and SLCX 12. Data from (Rubatto 2002) were used for comparison purposes.   Both the SLCX zircon/garnet REE partitioning coefficients and experimentally determined values show a U-shaped pattern with higher values for the light REE and heavy REE. Although the calculated partitioning coefficients do not exactly match the literature values, they show 	 70	similar trends, and rims/unzoned zircons match predicted values better than cores do. The calculated partitioning coefficients differ from Rubatto's values by the presence of lower Ce values (Zircon 1 and 3) and a negative Eu anomaly, which implies comparatively more reducing crystallization conditions for SLCX zircons (Trail et al., 2012).   Overall, the Dzircon/Cpx and Dzircon/Gt show considerable similarity to natural or experimentally determined values. Considering the Cpxs are in equilibrium with garnets, it is likely that garnet, zircon and clinopyroxene were in chemical equilibrium when formed. Partitioning coefficients for the redox-sensitive element, Ce, show significant difference between old cores and young rims, suggesting the redox conditions changed to more reducing conditions at the time the ~ 13 Ma zircons formed.  5.4.2 Magmatic vs. metamorphic origin of zircon cores and rims  The geochronology data clearly define two zircon groups with distinct ages: 1) two old zircon cores (Zircon1 and 3) with ~ 80 Ma ages and 2) two unzoned zircons (Zircon2 and 4) and rims (Zircon1 and 3) with younger ages ranging from 12.9 to 14.2 Ma. From the above evidence, it seems that both the cores and rims of the zircons have partitioning coefficients consistent with 	 71	formation in equilibrium with clinopyroxenes and garnet in samples SLCX 12 and SLCX 47. However, it is not clear whether the zircons formed by magmatic crystallization or metamorphic recrystallization or both. The REE plot (Figure 15, 17, 19 and 21) together with Th/U ratios of zircons (Figure 28 and 29) may provide insight into the origin of these zircons.  Both zircon cores show elevated Ce abundances, and a steep positive HREE trend, and the Zircon3 core shows a negative Eu anomaly (Figure 15 and Figure 19), features that distinguish igneous zircons from metamorphic and hydrothermal zircons (Hoskin and Ireland, 2000; Hoskin and Schaltegger, 2003). Th/U ratios for the two old cores (Figure 28) reveal that they have identical, high Th/U ratios (~ 0.8), which is also a feature commonly seen in igneous zircons (Hoskin and Schaltegger, 2003; Poletti et al., 2016). The available evidence suggests that the cores of Zircon1 (76.9 Ma) and Zircon3 (80.8 Ma) formed due to magmatic crystallization. 	 72	          Figure 28 Th/U vs. depth profile of two zircon cores.   The two rim domains and two unzoned zircons have similar REE patterns, but are characterized by lacking a positive Ce anomaly (Figure 15, 17, 19 & 21). Igneous zircons that lack a positive Ce anomaly have been found in kimberlite and lunar basalt samples (Belousova et al., 1998; 2002; Hoskin and Schaltegger, 2003). However, kimberlitic zircons have trace element abundances that are usually two orders of magnitude lower than in our samples (Grimes et al., 2015). Hydrothermal alteration, on the other hand, is able to produce zircons that are depleted in Ce. However, the REE patterns exhibited by the cores and rims are identical, implying that the composition of melts that were in equilibrium with the zircons should be similar. This makes the possibility of a hydrothermal origin of the rim unlikely. Metamorphic solid-state recrystallization, 	 73	on the other hand, could result in depletion in Ce. Similar trends have been documented by other researchers looking at zircons with magmatic cores and metamorphic rims (Belousova et al., 2002; Cates and Mojzsis, 2009; Hoskin and Schaltegger, 2003; Kirkland et al., 2015). Furthermore, lack of a positive Ce anormaly is considered a characteristic of metamorphic rims (Hoskin & Black, 2000). All this evidence points to a metamorphic origin for the rims and unzoned zircons.  The Th/U ratios for three out of four zircons drop from the core to the rim (Figure 29), and this trend is consistent with a metamorphic rim origin (Hoskin and Schaltegger, 2003). The decreasing Th/U ratios can be attributed to either the formation of Th-compatible phases such as monazite, allanite etc. during metamorphism (Möller et al., 2003), or increasing U4+ content in zircon with consumption of external U6+ when the redox condition becomes more reducing (Hoskin and Schaltegger, 2003). Additionally, Hoskin & Black (2000) suggested that during recrystallization, compared to U4+, Th4+ would be preferentially purged from the zircon lattice due to its larger ionic radius, resulting in lower Th/U ratios. Thus, the decreasing Th/U ratios observed in Zircon1, 2 and 3 rims are consistent with a metamorphic recrystallization origin.  	 74	   Figure 29 Th/U vs. depth profile of zircon rims.   The reason for the abrupt Th/U depletion shown by Zircon3's rim from 2.2 µm to 9.2 µm is unknown. The periodic pattern exhibited by Zircon4 is either due to the interaction between crystals and melt during rim growth, or reflect the occurrence of fractures and cracks within the zircon. Zircons from SLCX 12 show more variation in Th/U ratios compared to SLCX 47, which may indicate that they experienced more intense metamorphism or metasomatism, which created local disequilibrium during rim growth. .   In summary, both REE plot and Th/U ratios reveal that the low-age (12.9-14.5 Ma) zircon rims are overgrowths formed due to metamorphism. The ~ 80 Ma old cores are products of 	 75	magmatic crystallization. Decreasing Th/U ratios exhibited by the rims indicates a shift from relatively oxidizing conditions to more reducing conditions during metamorphism.    5.4.3 Interpretation of ages  Zircons from the pyroxenites record two major events. The steep positive REE patterns from La to Lu, elevated Ce abundance, negative Eu anomaly, along with high Th/U ratios all point to an igneous origin for the cores for Zircon1 and Zircon3. Since the cores are in equilibrium with the clinopyroxenes and garnets, the 80.8 ± 2 Ma is best interpreted as the igneous crystallization age of SLCX 12. The 76.9 Ma date, on the other hand, represents the minimum igneous crystallization age of SLCX 47.   Zircon2 and 4 and the rims of Zircon1 and 3 record a second period of zircon growth between 12.9 Ma and 14.5 Ma. The young zircon rims show many of the chemical characteristics of the old zircon cores (positive slope of REE plot, negative Eu anomaly) and even the compositions are similar, consistent with 'equilibrium' with the clinopyroxene and garnet. This suggests that they did not form as a result of new melt infiltrating the rocks. However, they have characteristics such as low Ce and lower Th/U ratios, consistent with 	 76	formation during a metamorphic event. Thus the younger 12.9-14.5 Ma dates are best interpreted as a metamorphic period. 5.5 Tectonic Implications  To my knowledge, before this study, the age of the oceanic lithospheric and asthenospheric mantle has never been quantitatively dated because mantle samples (xenoliths) are difficult to date with most of radiogenic isotopic dating systems (e.g. Rb-Sr, Nd-Sm). Uranium-Thorium-rich minerals permitting U/Th-Pb dating have never been observed in oceanic mantle xenoliths. There have been model Pb-Pb dates suggesting mantle rocks are ancient, but this study is unique in providing actual dates for mantle-derived rocks.   The 80.8 ± 2 Ma yielded by a zircon from SLCX 47 places timing constraints on the formation of the lithospheric mantle beneath Hawaii. This age is roughly coincident with when the ocean floor below Oahu formed at the Pacific mid ocean ridge (Lassiter et al., 2000; Norton, 2007). Therefore, there is the possibility that the formation of the pyroxenites (at least clinopyroxene and garnet) is related to crust formation at the mid ocean ridge. However, based on Hf-Nd-Sr isotope systematics, previous studies found that these xenoliths have near zero ages 	 77	and their isotopic compositions are unlikely linked to mid-ocean ridge basalt (Bizimis et al., 2005). However, if the temperature of the systems has consistently been higher than the closure temperatures, it is possible to produce the zero ages reported. Secondary overprinting is related to heating, metasomatism and magmatism by the Hawaiian plume occurring 12-14 Ma ago. Since then the continued cooling of the ocean floor captured the rocks and incorporated them into the lithosphere for sampling by the Honolulu magma that brought them to the surface 0.6 Ma ago.   Although the ~ 80 Ma ages are coincident with MORB melting to form ocean floor, the composition of SLCX is not MORB-like. Rather they resemble pyroxenite xenoliths from the North China Craton subcontinental lithosphere (Xu et al., 2002). If there is a detached, subcontinental lithosphere fragment entrained in the oceanic lithosphere mantle below Hawaii, the opening of the mid ocean ridge ~ 80 Ma ago may have lead to partial melting of this old, Pb-rich reservoir (Griffin et al., 2009) to form magma that underwent fractional crystallization in several magma chambers but with a similar tectonic setting. Subsequent thermal metamorphism, potentially caused by the Hawaiian mantle plume, could lead to the formation of zircon 	 78	overgrowth rims ~ 13 Ma ago. If this is true, it appears that the chemical heterogeneity existing within Earth's mantle is not only contributed by recycling of subducted oceanic crust and lithosphere, but also involving delaminated subcontinental lithosphere as a critical component.    	 79	CHAPTER Ⅵ CONCLUSIONS  Seven Salt Lake Crater garnet-bearing pyroxenite xenoliths are textually and compositionally distinct from each other, but share common geochemical signatures such as positive Pb anomaly in some clinopyroxenes and all garnets, depletion in HFSE and flat LREE and MREE trends. They are inferred as magmatic cumulates crystallized from melts that were potentially derived from partial melting of an old depleted delaminated subcontinental lithosphere fragment entrained in the mantle.   Ages produced by U-Pb dating are distinct from the estimated near-zero modelling ages reported by previous researchers. 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Because there was volcaniclastic nephelinite/nephelinitic host basalt attached to the xenolith (Figure 30 a), the first step was to remove the attached material using the selFrag at Queen's University. Before loading each sample, the vessel was carefully cleaned with the following steps: 1) rinsed with tap water, 2) hand-washed with mild detergent using a stiff plastic brush, 3) rinsed with tap water, and 4) the vessel loaded with a Grenville age marble and processed through the selFrag. Samples were loaded with RO water (3 L in total) purchased from Collagen Water. New brushes and plastic containers were used during each cleaning.  	 94	             Figure 30 SLCX processing photos. a) sample as received. b) sample after 'gentle' 40 pulses. c) sample after sieving. 'B' fraction was then subjected to a 'harder' additional 120 pulses. Photos were taken by Daniel Layton-Mathews, Queen's University.   After each cleaning procedure, samples and 3 L of reverse osmosis water were placed inside the selFrag instrument and subjected to 40 pulses at 130 kV, which 'gently' separated the volcanic material from the xenoliths. A 1.4 mm wet sieve was used to divide the products into A (volcanic material < 1.4 mm in size, Figure 30 b) and B (material > 1.4 mm in size, Figure 30 c) subgroups. The subgroup B, which largely contains xenolith material, was placed back into the selFrag with reverse osmosis water and subjected to 120 pulses at 150 kV for disaggregation 	 95	along grain boundaries. With the above procedures, the xenoliths were disaggregated and zircon from along grain boundaries separated.   The products derived from the selFrag at Queen's University were then sieved at the Jack Satterly Geochronology Laboratory, University of Toronto (U of T) to remove coarse mineral grains. A Franz magnetic separator was used to concentrate non-magnetic grains. Before and between samples, the separator was cleaned with water, distilled water and methanol. Magnetic grains were removed from the material with the following steps: 1) free-fall removal of magnetic minerals, 2) two passes through the magnetic separator. Next, the 'non-magnetic' fraction went through methylene iodide heavy liquid for additional separation. Glassware used before and between samples was fastidiously cleaned. Seven zircons were recovered from the xenoliths (four from SLCX 12, third sample processed; and three from SLCX 47, last sample processed).  Because there was the possibility that the recovered zircons were contaminants from previously-processed samples in the instruments, records of samples previously processed in the two laboratories were carefully examined. Prior to the selFrag mineral disaggregation, a large three-week project was conducted by Himalayan structural geologist Dr. Laurent Godin. All of 	 96	his samples were Archean granites, roughly 3.2 to 3.0 Ga from the Bundelkhand massif in India. Our zircons yielded ~ 13 Ma and ~ 80 Ma ages, so it is almost impossible that these zircons were from his granites. During the separation at University of Toronto, no samples went through the equipment over the time of our zircon separation, and rocks processed over the year prior to our project did not have similar ages to our zircons.   To summarize, it is practically impossible that our zircons are contaminants from rocks processed prior to our project at Queen's University or University of Toronto. The samples went through the instruments in numerical order, and it is extremely unlikely that after all previous samples went through the selFrag, contaminating zircons could survive from the multi-cleaning process and appear when the last sample (SLCX 47) was processed. The zircons cannot be from the xenolith-host material because the volcaniclastic rocks are < 0.6 Ma old (Clague and Frey, 1982). Therefore, it is clear that the recovered zircons are derived from the Salt Lake Crater xenoliths.     	 97	Appendix B Mineral Composition Data Table 10 Major Element Concentrations and Calculated Stoichiometry for Clinopyroxene   SLCX 47 Cpx1 SLCX 47 Cpx2 SLCX 47 Cpx3 SLCX 47 Cpx4 SLCX 12 Cpx1 SiO2 50.45 50.24 50.32 50.01 51.40 TiO2 1.16 1.15 1.21 1.27 0.99 Al2O3 6.50 6.43 6.64 7.02 7.45 Cr2O3 0.02 0.04 0.04 0.03 0.39 FeO 6.47 6.51 6.65 6.56 6.04 MnO 0.06 0.05 0.10 0.08 0.09 MgO 13.90 13.95 13.79 13.70 13.77 CaO 19.21 19.17 19.12 18.80 17.71 Na2O 1.90 1.93 1.97 1.96 2.45 K2O 0.02 0.01 0.02 0.01 0.02 NiO 0.04 0.02 0.02 0.04 0.02 Total 99.73 99.52 99.87 99.48 100.33 Number of ions on the basis of 6 O Si 1.859 1.857 1.854 1.848 1.870 Ti 0.032 0.032 0.034 0.035 0.027 Al(IV) 0.141 0.143 0.146 0.152 0.130 Al(VI) 0.142 0.137 0.142 0.153 0.189 Cr 0.001 0.001 0.001 0.001 0.011 Fe++ 0.200 0.201 0.205 0.203 0.184 Mn 0.002 0.002 0.003 0.003 0.003 Mg 0.764 0.769 0.758 0.755 0.747 Ca 0.759 0.759 0.755 0.744 0.690 Na 0.136 0.138 0.141 0.140 0.173 K 0.001 0.001 0.001 0.001 0.001 Total 4.035 4.040 4.039 4.034 4.025 En 44.35 44.46 44.11 44.35 46.09 Fs 11.59 11.64 11.93 11.92 11.33 Wo 44.06 43.91 43.96 43.74 42.58 Mg# 79 79 79 79 80 * En = Enstatite, Fs = Ferrosilite, Wo = Wollastonite, Mg# = [Mg/(Mg + Fe)]*100%. The total Fe is reported as Fe++.   	 98	Table 10 (Continued)  SLCX 12 Cpx2 SLCX 25 Cpx1 SLCX 25 Cpx2 SLCX 25 Cpx3 SLCX 26 Cpx2 SiO2 51.19 51.15 49.98 50.57 49.84 TiO2 1.01 0.84 0.90 0.87 1.07 Al2O3 7.48 6.88 8.10 7.44 6.27 Cr2O3 0.48 0.22 0.23 0.23 0.21 FeO 5.81 6.31 5.96 6.12 5.85 MnO 0.10 0.06 0.05 0.09 0.10 MgO 13.68 14.20 13.54 14.06 13.93 CaO 17.68 18.59 18.87 18.75 19.61 Na2O 2.42 2.04 2.18 2.02 1.76 K2O 0.03 0.01 0.03 0.01 0.04 NiO 0.04 0.03  0.04 0.04 Total 99.92 100.36 99.86 100.20 98.71  Number of ions on the basis of 6 O Si 1.869 1.866 1.834 1.849 1.856 Ti 0.028 0.023 0.025 0.024 0.030 Al(IV) 0.131 0.134 0.159 0.151 0.144 Al(VI) 0.191 0.163 0.188 0.170 0.131 Cr 0.014 0.006 0.007 0.007 0.006 Fe++ 0.177 0.193 0.183 0.187 0.182 Mn 0.003 0.002 0.002 0.003 0.003 Mg 0.745 0.773 0.741 0.766 0.773 Ca 0.691 0.727 0.742 0.735 0.783 Na 0.172 0.145 0.155 0.143 0.127 K 0.001 0.000 0.001 0.000 0.002 Total 4.022 4.032 4.040 4.035 4.037 En 46.16 45.66 44.47 45.40 44.50 Fs 10.99 11.39 10.98 11.08 10.48 Wo 42.85 42.96 44.55 43.52 45.02 Mg# 81 80 80 80 81    	 99	Table 10 (Continued)  SLCX 45 Cpx1 SLCX 45 Cpx2 SLCX 45 Cpx3 SLCX 21 Cpx1 SLCX 21 Cpx2 SiO2 51.35 51.63 51.53 48.58 49.67 TiO2 0.59 0.54 0.56 1.44 1.19 Al2O3 6.19 6.02 6.11 8.26 7.60 Cr2O3 0.34 0.39 0.38 0.03 0.03 FeO 5.32 5.44 5.42 7.82 8.28 MnO 0.08 0.08 0.09 0.08 0.09 MgO 14.37 14.49 14.43 11.77 11.81 CaO 19.37 19.45 19.37 18.33 18.32 Na2O 1.92 1.92 1.92 2.61 2.81 K2O 0.01 0.04 0.01 0.03 0.04 NiO 0.02 0.06 0.06 0.07 0.02 Total 99.58 100.08 99.88 99.02 99.85  Number of ions on the basis of 6 O Si 1.884 1.887 1.887 1.818 1.844 Ti 0.016 0.015 0.015 0.041 0.033 Al(IV) 0.116 0.113 0.113 0.182 0.156 Al(VI) 0.152 0.147 0.150 0.183 0.177 Cr 0.010 0.011 0.011 0.001 0.001 Fe++ 0.163 0.166 0.166 0.245 0.257 Mn 0.002 0.003 0.003 0.002 0.003 Mg 0.786 0.790 0.788 0.657 0.654 Ca 0.762 0.762 0.760 0.735 0.729 Na 0.137 0.136 0.136 0.190 0.202 K 0.001 0.002 0.001 0.002 0.002 Total 4.029 4.032 4.029 4.054 4.057 En 45.94 45.97 45.97 40.12 39.87 Fs 9.54 9.68 9.68 14.96 15.68 Wo 44.52 44.35 44.35 44.92 44.45 Mg# 83 83 83 73 72    	 100	Table 10 (Continued)  SLCX 21 Cpx3 SLCX 11 Cpx1 SLCX 11 Cpx2 SLCX 11 Cpx3 SiO2 49.07 50.11 49.87 49.93 TiO2 1.26 1.22 1.23 1.25 Al2O3 7.76 6.68 6.72 6.83 Cr2O3 0.01 0.04 0.04 0.04 FeO 7.86 6.93 6.77 6.89 MnO 0.09 0.11 0.09 0.12 MgO 12.17 13.52 13.61 13.37 CaO 18.92 18.71 18.77 18.43 Na2O 2.35 2.02 2.01 2.15 K2O 0.02 0.01 0.01 0.10 NiO 0.05 0.04 0.05 0.07 Total 99.56 99.40 99.16 99.18  Number of ions on the basis of 6 O Si 1.827 1.856 1.852 1.854 Ti 0.035 0.034 0.034 0.035 Al(IV) 0.173 0.144 0.148 0.146 Al(VI) 0.168 0.148 0.146 0.153 Cr 0.000 0.001 0.001 0.001 Fe++ 0.245 0.215 0.210 0.214 Mn 0.003 0.003 0.003 0.004 Mg 0.675 0.746 0.753 0.740 Ca 0.755 0.743 0.747 0.734 Na 0.170 0.145 0.145 0.155 K 0.001 0.000 0.000 0.005 Total 4.052 4.036 4.039 4.040 En 40.32 43.81 44.05 43.86 Fs 14.62 12.61 12.29 12.69 Wo 45.06 43.58 43.66 43.46 Mg# 73 78 78 78    	 101	Table 11 Major Element Concentrations and Calculated Stoichiometry for Orthopyroxene  SLCX 12  Opx1 SLCX 12  Opx2 SLCX 12 Opx3 SLCX 25  Opx1 SLCX 25 Opx2 SiO2 53.62 53.19 51.68 53.01 53.12 TiO2 0.28 0.28 0.25 0.26 0.27 Al2O3 4.60 4.84 4.93 4.35 4.18 Cr2O3 0.22 0.20 0.22 0.12 0.11 FeO 11.76 11.76 11.58 13.09 11.64 MnO 0.15 0.15 0.17 0.16 0.15 MgO 28.76 28.40 27.47 28.25 28.83 CaO 0.92 0.97 0.93 0.86 0.86 Na2O 0.23 0.37 0.56 0.20 0.28 K2O 0.01 0.02 0.25 0.02 0.03 NiO 0.05 0.09 0.08 0.06 0.05 Total 100.61 100.27 98.13 100.39 99.53 Number of ions on the basis of 6 O Si 1.891 1.885 1.877 1.887 1.895 Ti 0.007 0.007 0.007 0.007 0.007 Al(IV) 0.109 0.115 0.123 0.113 0.105 Al(VI) 0.083 0.087 0.088 0.069 0.070 Cr 0.006 0.006 0.006 0.003 0.003 Fe++ 0.347 0.349 0.352 0.390 0.347 Mn 0.004 0.005 0.005 0.005 0.005 Mg 1.512 1.500 1.487 1.499 1.533 Ca 0.035 0.037 0.036 0.033 0.033 Na 0.016 0.026 0.039 0.014 0.020 K 0.000 0.001 0.012 0.001 0.001 Total 4.011 4.017 4.033 4.021 4.019 En 79.84 79.56 79.31 78.00 80.13 Fs 18.32 18.49 18.76 20.28 18.15 Wo 1.84 1.95 1.93 1.72 1.72 Mg# 81 81 81 79 82 * En = Enstatite, Fs = Ferrosilite, Wo = Wollastonite, Mg# = [Mg/(Mg + Fe)]*100%. The total Fe is reported as Fe++.    	 102	Table 11 (Continued)  SLCX 25  Opx3 SLCX 26  Opx1 SLCX 26  Opx2 SLCX 11  Opx1 SiO2 53.10 51.88 52.20 53.17 TiO2 0.25 0.31 0.27 0.32 Al2O3 4.04 5.35 5.60 3.96 Cr2O3 0.11 0.10 0.07 0.03 FeO 13.11 11.73 11.85 13.08 MnO 0.17 0.14 0.18 0.15 MgO 28.10 28.07 28.04 28.23 CaO 0.88 0.85 0.89 0.88 Na2O 0.19 0.35 0.17 0.15 K2O 0.02 0.05 0.04 0.01 NiO 0.07 0.03 0.07 0.09 Total 100.05 98.86 99.38 100.07 Number of ions on the basis of 6 O Si 1.896 1.865 1.867 1.898 Ti 0.007 0.008 0.007 0.009 Al(IV) 0.104 0.135 0.133 0.102 Al(VI) 0.067 0.092 0.102 0.064 Cr 0.003 0.003 0.002 0.001 Fe++ 0.392 0.353 0.354 0.390 Mn 0.005 0.004 0.006 0.004 Mg 1.496 1.505 1.495 1.502 Ca 0.034 0.033 0.034 0.034 Na 0.013 0.024 0.012 0.010 K 0.001 0.002 0.002 0.001 Total 4.017 4.025 4.014 4.015 En 77.87 79.62 79.38 77.99 Fs 20.38 18.66 18.82 20.27 Wo 1.75 1.72 1.81 1.74 Mg# 79 81 81 79    	 103	Table 12 Major Element Concentrations and Calculated Stoichiometry for Garnet  SLCX 47  Gt1 SLCX 47  Gt2 SLCX 47  Gt3 SLCX 47  Gt4 SLCX 12  Gt1 SiO2 40.73 41.01 40.25 40.95 41.22 TiO2 0.38 0.41 0.46 0.30 0.28 Al2O3 22.76 23.47 23.10 23.51 23.33 Cr2O3 0.03 0.05 0.03 0.04 0.41 FeO 14.43 14.12 13.58 13.96 13.50 MnO 0.32 0.35 0.32 0.31 0.39 MgO 16.46 16.64 16.37 16.88 17.04 CaO 4.84 5.25 5.22 5.23 4.85 Na2O 0.13 0.06 0.11 0.08 0.11 K2O 0.10 0.01 0.03 0.02 0.04 NiO    0.01 0.03 Total 100.20 101.35 99.46 101.30 101.21 Number of ions on the basis of 12 O Si 2.974 2.952 2.951 2.948 2.965 Ti 0.021 0.022 0.026 0.016 0.015 Al 1.958 1.991 1.996 1.995 1.977 Cr 0.002 0.003 0.002 0.002 0.023 Fe++ 0.881 0.850 0.832 0.841 0.812 Mn 0.020 0.021 0.020 0.019 0.024 Mg 1.791 1.785 1.789 1.812 1.828 Ca 0.379 0.405 0.410 0.404 0.374 Total 8.026 8.029 8.025 8.037 8.019 Alm 28.88 27.96 27.46 27.50 26.94 Prp 58.71 58.72 59.01 59.29 60.64 Grs 12.41 13.32 13.53 13.21 12.41 Mg# 67 68 68 68 69 * Alm = Almandine, Prp = Pyrope, Grs = Grossular, Mg# = [Mg/(Mg + Fe)]*100%. The total Fe is reported as Fe++.     	 104	Table 12 (Continued)  SLCX 12  Gt2 SLCX 12  Gt3 SLCX 25  Gt1 SLCX 25  Gt2 SLCX 25  Gt3 SiO2 40.88 40.82 40.97 40.98 40.67 TiO2 0.26 0.33 0.23 0.22 0.24 Al2O3 23.43 23.24 23.38 23.17 23.19 Cr2O3 0.25 0.26 0.29 0.29 0.29 FeO 13.51 13.33 14.81 13.18 14.53 MnO 0.37 0.37 0.43 0.43 0.40 MgO 16.76 16.88 16.41 16.87 16.14 CaO 4.80 4.87 5.11 5.13 5.11 Na2O 0.37 0.30 0.07 0.15 0.11 K2O 0.03 0.17 0.01 0.04 0.05 NiO 0.02 0.04  0.03 0.03 Total 100.70 100.62 101.70 100.50 100.77 Number of ions on the basis of 12 O Si 2.962 2.962 2.950 2.969 2.956 Ti 0.014 0.018 0.012 0.012 0.013 Al 2.001 1.987 1.984 1.979 1.987 Cr 0.014 0.015 0.017 0.017 0.017 Fe++ 0.818 0.809 0.892 0.799 0.884 Mn 0.023 0.023 0.026 0.027 0.025 Mg 1.810 1.826 1.761 1.822 1.749 Ca 0.373 0.379 0.394 0.398 0.398 Total 8.016 8.019 8.037 8.022 8.029 Alm 27.26 26.84 29.27 26.46 29.15 Prp 60.31 60.59 57.80 60.36 57.72 Grs 12.42 12.57 12.94 13.19 13.13 Mg# 69 69 66 70 66    	 105	Table 12 (Continued)  SLCX 26  Gt1 SLCX 45  Gt1 SLCX 21  Gt1 SLCX 21  Gt2 SLCX 11  Gt1 SiO2 40.66 40.58 40.27 40.39 41.05 TiO2 0.25 0.49 0.32 0.30 0.33 Al2O3 22.98 22.88 22.94 23.00 23.08 Cr2O3 0.28 0.09 0.02 0.02 0.06 FeO 13.32 15.48 16.88 16.79 14.70 MnO 0.41 0.30 0.35 0.38 0.36 MgO 16.42 15.73 14.29 14.30 16.21 CaO 5.43 5.12 5.77 5.67 5.14 Na2O 0.19 0.07 0.10 0.08 0.04 K2O 0.04 0.01 0.03 0.02 0.01 NiO 0.02 0.05 0.03 0.04 0.03 Total 99.99 100.80 100.99 100.99 101.01 Number of ions on the basis of 12 O Si 2.967 2.959 2.956 2.961 2.972 Ti 0.014 0.027 0.017 0.016 0.018 Al 1.976 1.966 1.984 1.988 1.970 Cr 0.016 0.005 0.001 0.001 0.004 Fe++ 0.813 0.944 1.036 1.029 0.890 Mn 0.026 0.018 0.022 0.023 0.022 Mg 1.786 1.710 1.563 1.564 1.750 Ca 0.424 0.400 0.454 0.445 0.399 Total 8.023 8.029 8.034 8.028 8.023 Alm 26.89 30.91 33.93 33.88 29.29 Prp 59.07 55.99 51.21 51.46 57.59 Grs 14.04 13.10 14.86 14.65 13.12 Mg# 69 64 60 60 66    	 106	Table 12 (Continued)  SLCX 11  Gt2 SLCX 11  Gt3  SiO2 40.63 40.82  TiO2 0.33 0.41  Al2O3 23.10 22.97  Cr2O3 0.05 0.04  FeO 14.58 14.58  MnO 0.35 0.35  MgO 15.91 15.94  CaO 5.15 5.18  Na2O 0.06 0.05  K2O 0.01 0.01  NiO 0.04 0.02  Total 100.19 100.38   Number of ions on the basis of 12 O Si 2.967 2.974  Ti 0.018 0.022  Al 1.987 1.972  Cr 0.003 0.003  Fe++ 0.890 0.889  Mn 0.022 0.022  Mg 1.731 1.731  Ca 0.403 0.404  Total 8.020 8.017  Alm 29.44 29.38  Prp 57.25 57.25  Grs 13.21 13.37  Mg# 66 66     	 107	Table 13 Major Element Concentrations and Calculated Stoichiometry for Olivine  SLCX 47  Ol1 SLCX 47  Ol2 SLCX 47  Ol3 SLCX 47  Ol4 SLCX 25  Ol1 SiO2 39.05 38.71 38.73 37.94 39.00 TiO2 0.04 0.03 0.02 0.03 0.03 Al2O3 0.01 0.01 0.01 0.03 0.02 Cr2O3 0.01   0.01 0.01 FeO 19.89 19.65 19.73 19.86 20.19 MnO 0.13 0.12 0.16 0.14 0.13 MgO 41.34 40.90 41.16 40.19 40.78 CaO 0.06 0.07 0.08 0.15 0.07 Na2O 0.07 0.05 0.06 0.28 0.03 K2O 0.01 0.03 0.03 0.13 0.01 NiO 0.31 0.27 0.29 0.28 0.27 Total 100.63 99.57 99.98 98.76 100.26 Number of ions on the basis of 4 O Si 0.996 0.997 0.995 0.993 0.999 Ti 0.001 0.001 0.000 0.001 0.001 Al 0.000 0.000 0.000 0.001 0.000 Cr 0.000 0.000 0.000 0.000 0.000 Fe++ 0.424 0.423 0.424 0.435 0.433 Mn 0.003 0.003 0.004 0.003 0.003 Mg 1.572 1.571 1.576 1.568 1.558 Ni 0.006 0.006 0.006 0.006 0.006 Ca 0.002 0.002 0.002 0.004 0.002 TOTAL 3.005 3.003 3.007 3.010 3.002 Fo 78.75 78.77 78.81 78.30 78.27 Fa 21.25 21.23 21.19 21.70 21.73 Mg# 79 79 79 78 78 * Fo = Forsterite, Fa = Fayalite, Mg# = [Mg/(Mg + Fe)]*100%. The total Fe is reported as Fe++.    	 108	Table 13 (Continued)  SLCX 45  Ol1 SLCX 11  Ol1 SLCX 11  Ol2 SiO2 39.32 38.80 38.78 TiO2 0.02 0.02 0.01 Al2O3 0.01 0.02 0.01 Cr2O3 0.02 0.01  FeO 17.33 20.97 21.07 MnO 0.14 0.18 0.15 MgO 42.96 40.43 40.48 CaO 0.06 0.11 0.07 Na2O 0.02 0.03 0.02 K2O 0.01 0.02 0.02 NiO 0.37 0.29 0.29 Total 99.88 100.58 100.63 Number of ions on the basis of 4 O Si 0.998 0.996 0.995 Ti 0.000 0.000 0.000 Al 0.000 0.001 0.000 Cr 0.000 0.000 0.000 Fe++ 0.368 0.450 0.452 Mn 0.003 0.004 0.003 Mg 1.625 1.547 1.548 Ni 0.008 0.006 0.006 Ca 0.002 0.003 0.002 TOTAL 3.003 3.006 3.007 Fo 81.55 77.47 77.40 Fa 18.45 22.53 22.60 Mg# 82 77 77    	 109	Table 14 Major and Trace Element Concentrations for Clinopyroxene from LA-ICP-MS  SLCX 11 Cpx1 SLCX 11 Cpx3 SLCX 12 Cpx1 SLCX 12 Cpx2 SLCX 21 Cpx3 wt%      SiO2 50.11 49.93 51.40 51.19 49.07 TiO2 1.22 1.25 0.99 1.01 1.26 Al2O3 6.68 6.83 7.45 7.48 7.76 Cr2O3 0.04 0.04 0.39 0.48 0.01 FeO 6.93 6.89 6.04 5.81 7.86 MnO 0.11 0.12 0.09 0.10 0.09 MgO 13.52 13.37 13.77 13.68 12.17 CaO 18.71 18.43 17.71 17.68 18.92 Na2O 2.02 2.15 2.45 2.42 2.35 K2O 0.01 0.10 0.02 0.03 0.02 NiO 0.04 0.07 0.02 0.04 0.05 Total 99.40 99.18 100.33 99.92 99.56 ppm      Rb Bld. Bld. 0.3 0.039 Bld. Sr 162.1 165.4 232.3 211.3 163.1 Y 7.49 6.42 6.14 5.24 4.08 Zr 51.2 44.3 39.5 34.5 66.4 Nb 0.399 0.451 1.021 0.93 0.381 Sb Bld. Bld. Bld. Bld. Bld. Cs Bld. Bld. Bld. Bld. Bld. Ba 0.296 0.162 53 0.58 0.192 La 3.82 3.77 4.08 3.89 3.73 Ce 10.97 11.3 11 11.35 13.76 Pr 2.095 2.105 1.842 1.71 2.57 Nd 13.01 12.28 9.08 8.12 14.79 Sm 4.51 4.24 2.72 2.55 4.86 Eu 1.65 1.63 1.094 0.978 1.746 Gd 4.41 3.92 2.49 2.19 4.23 Tb 0.549 0.532 0.377 0.341 0.474 Dy 2.59 2.28 1.9 1.47 1.74 Ho 0.32 0.256 0.235 0.184 0.168 Er 0.517 0.42 0.514 0.481 0.2 Yb 0.165 0.155 0.197 0.174 0.044 Lu Bld. 0.013 0.0279 0.0216 Bld. Hf 2.77 2.09 1.44 1.4 3.7 *Bld. = Below detecting limit 	 110	Table 14 (Continued) Ta 0.096 0.08 0.112 0.124 0.048 Pb 1.423 0.414 1.48 0.366 0.214 Th 0.253 0.228 0.053 0.072 0.188 U 0.052 0.0503 0.0177 0.0169 0.0362 P 93 86.3 144.7 135.8 92.8 Sc 36.33 33.85 52.5 49.62 21.28 V 460.5 458.2 417 421.1 436.6 Co 51.35 52.47 39.23 38.22 49.75 Cu 1.692 1.526 4.82 4.65 0.594 Zn 95.5 94.4 53.3 53.8 91.9 As Bld. Bld. Bld. 8.1 Bld.    	 111	Table 14 (Continued)  SLCX 25 Cpx1 SLCX 25 Cpx2 SLCX 25 Cpx3 SLCX 26 Cpx2 SLCX 45 Cpx1 wt%      SiO2 51.15 50.16 50.57 49.84 51.35 TiO2 0.84 0.82 0.87 1.07 0.59 Al2O3 6.88 7.87 7.44 6.27 6.19 Cr2O3 0.22 0.23 0.23 0.21 0.34 FeO 6.31 6.54 6.12 5.85 5.32 MnO 0.06 0.07 0.09 0.10 0.08 MgO 14.20 15.11 14.06 13.93 14.37 CaO 18.59 16.38 18.75 19.61 19.37 Na2O 2.04 1.91 2.02 1.76 1.92 K2O 0.01 0.03 0.01 0.04 0.01 NiO 0.03 0.05 0.04 0.04 0.02 Total 100.36 99.16 100.20 98.71 99.58 ppm      Rb Bld. Bld. 0.44 Bld. 0.098 Sr 158.4 158.3 157.8 116.2 150.4 Y 7.52 10.08 8.44 4.46 7.28 Zr 43.8 43 31 24.9 22.54 Nb 0.605 0.829 0.794 0.928 0.835 Sb Bld. Bld. Bld. Bld. Bld. Cs Bld. Bld. Bld. Bld. Bld. Ba 0.179 0.14 14.1 1.42 0.67 La 4.3 4.58 4.55 3.45 3.1 Ce 12.17 12.83 11.65 9.38 6.78 Pr 2.054 2.133 1.995 1.492 1.099 Nd 10.37 11.11 9.8 8.74 5.9 Sm 3.11 3.33 2.99 2.81 1.99 Eu 1.15 1.166 1.149 1.03 0.743 Gd 2.7 3.16 2.64 2 2.32 Tb 0.465 0.529 0.445 0.357 0.346 Dy 2.2 2.51 2.24 1.59 1.81 Ho 0.291 0.387 0.31 0.185 0.291 Er 0.628 0.89 0.726 0.344 0.7 Yb 0.269 0.437 0.356 0.103 0.48 Lu 0.029 0.042 0.0351 0.0192 0.045 Hf 1.53 1.64 1.27 1.32 0.89    	 112	Table 14 (Continued) Ta 0.175 0.234 0.137 0.073 0.065 Pb 0.421 0.443 0.703 0.33 0.39 Th 0.224 0.288 0.25 0.178 0.19 U 0.0351 0.0337 0.0404 0.0489 0.0471 P 153.8 147.4 136.7 187 192.9 Sc 53.43 62.5 56.16 41.9 50 V 402.1 387 398.9 542 358 Co 35.52 34.02 35.98 41.5 43 Cu 2.2 2.32 2.27 2.74 9.9 Zn 56.6 49.1 48.9 45.1 54.4 As 8.8 Bld. Bld. Bld. 3.27    	 113	Table 14 (Continued)  SLCX 45 Cpx3 SLCX 47 Cpx1 SLCX 47 Cpx2 SLCX 47 Cpx3 SLCX 47 Cpx4 wt%      SiO2 51.53 50.45 50.24 50.32 50.01 TiO2 0.56 1.16 1.15 1.21 1.27 Al2O3 6.11 6.50 6.43 6.64 7.02 Cr2O3 0.38 0.02 0.04 0.04 0.03 FeO 5.42 6.47 6.51 6.65 6.56 MnO 0.09 0.06 0.05 0.10 0.08 MgO 14.43 13.90 13.95 13.79 13.70 CaO 19.37 19.21 19.17 19.12 18.80 Na2O 1.92 1.90 1.93 1.97 1.96 K2O 0.01 0.02 0.01 0.02 0.01 NiO 0.06 0.04 0.02 0.02 0.04 Total 99.88 99.73 99.52 99.87 99.48 ppm      Rb 0.064 0.063 0.039 Bld. Bld. Sr 155.6 108.6 103.3 103.5 113.5 Y 4.24 5.79 4.91 5.37 6.34 Zr 19.78 38.3 31.4 35.3 39.5 Nb 0.694 0.406 0.336 0.371 0.521 Sb 0.223 Bld. Bld. Bld. Bld. Cs Bld. Bld. Bld. Bld. Bld. Ba 0.393 0.4 0.289 0.279 0.243 La 3.12 2.76 2.465 2.7 2.873 Ce 8.01 9.01 8.36 8.69 9.22 Pr 1.186 1.677 1.548 1.611 1.705 Nd 6.06 9.48 8.63 8.97 9.86 Sm 1.85 3.17 2.69 3.11 3.07 Eu 0.708 1.193 1.075 1.218 1.278 Gd 2.07 2.54 2.42 2.6 2.95 Tb 0.233 0.446 0.407 0.416 0.45 Dy 1.16 1.84 1.62 1.74 1.95 Ho 0.162 0.232 0.204 0.205 0.258 Er 0.282 0.431 0.33 0.41 0.452 Yb 0.104 0.16 0.142 0.073 0.17 Lu 0.0077 0.0145 Bld. 0.00019 0.0092 Hf 0.798 1.89 1.6 1.55 1.92  	 114	Table 14 (Continued) Ta 0.078 0.0557 0.0313 0.0401 0.0603 Pb 0.814 0.747 2.11 0.621 0.776 Th 0.192 0.129 0.096 0.119 0.122 U 0.0292 0.0368 0.0219 0.0199 0.0276 P 136.8 170 148 184 145.8 Sc 38.46 38.49 36.98 34.96 36 V 409.2 470 460.7 463.9 462.8 Co 40.83 42.43 43.55 42.99 43 Cu 5.3 3.76 3.22 2.91 3.02 Zn 50.9 61.3 61.4 56.9 57.3 As Bld. Bld. Bld. Bld. Bld.    	 115	Table 15 Major and Trace Element Concentrations for Garnet from LA-ICP-MS  SLCX 11 Gt1 SLCX 11 Gt3 SLCX 12 Gt1 SLCX 12 Gt2 SLCX 12 Gt3 wt%      SiO2 40.63 40.82 41.22 40.88 40.82 TiO2 0.33 0.41 0.28 0.26 0.33 Al2O3 23.10 22.97 23.33 23.43 23.24 Cr2O3 0.05 0.04 0.41 0.25 0.26 FeO 14.58 14.58 13.50 13.51 13.33 MnO 0.35 0.35 0.39 0.37 0.37 MgO 15.91 15.94 17.04 16.76 16.88 CaO 5.15 5.18 4.85 4.80 4.87 Na2O 0.06 0.05 0.11 0.37 0.30 K2O 0.01 0.01 0.04 0.03 0.17 NiO 0.04 0.02 0.03 0.02 0.04 Total 100.19 100.38 101.21 100.70 100.62 ppm      Rb Bld. Bld. Bld.  Bld. Sr 0.611 1.39 0.914 0.77 1.425 Y 39.25 48.24 20.94 52.3 27.63 Zr 46.4 45 17.1 33.6 20.9 Nb 0.0182 0.036 0.036 Bld. 0.04 Sb Bld. Bld. Bld. Bld. Bld. Cs Bld. Bld. Bld. Bld. Bld. Ba 0.35 0.92 0.7 Bld. 0.89 La Bld. Bld. 0.0017 Bld. Bld. Ce 0.12 0.1 0.096 0.38 0.081 Pr 0.037 0.063 0.041 0.102 0.047 Nd 0.86 0.78 0.413 4.7 0.63 Sm 1.2 1.37 0.79 3.4 0.9 Eu 0.967 0.982 0.525 2.33 0.63 Gd 3.6 3.85 1.63 4.9 1.91 Tb 0.944 0.998 0.485 1.23 0.561 Dy 7.75 8.38 3.86 11.9 4.35 Ho 1.518 1.84 0.751 1.96 1.02 Er 4.16 5.21 2.22 7.1 3.03 Yb 2.98 4.71 2.01 7.7 3.15 Lu 0.318 0.534 0.245 0.95 0.442 Hf 0.91 0.79 0.162 0.39 0.185  	 116	Table 15 (Continued) Ta Bld. Bld. Bld.   Bld. Pb 0.896 1.002 0.355 Bld. 0.24 Th Bld. Bld. Bld. Bld. Bld. U Bld. Bld. Bld. 0.0038 Bld. P 117.3 126.1 263 402 282 Sc 75.7 72.7 84.3 186.5 83.8 V 164.8 157.6 115.4 121.7 109.6 Co 85.6 89.5 64 85.2 63.4 Cu 0.33 1 0.316 0.18 0.314 Zn 102.6 119.5 71.1 122 59.6 As Bld. Bld. Bld. Bld. Bld.    	 117	Table 15 (Continued)  SLCX 21 Gt1 SLCX 25 Gt1 SLCX 25 Gt2 SLCX 26 Gt1 SLCX 47 Gt1 wt%      SiO2 40.27 40.97 40.98 40.66 40.73 TiO2 0.32 0.23 0.22 0.25 0.38 Al2O3 22.94 23.38 23.17 22.98 22.76 Cr2O3 0.02 0.29 0.29 0.28 0.03 FeO 16.88 14.81 13.18 13.32 14.43 MnO 0.35 0.43 0.43 0.41 0.32 MgO 14.29 16.41 16.87 16.42 16.46 CaO 5.77 5.11 5.13 5.43 4.84 Na2O 0.10 0.07 0.15 0.19 0.13 K2O 0.03 0.01 0.04 0.04 0.10 NiO 0.03  0.03 0.02  Total 100.99 101.70 100.50 99.99 100.20 ppm      Rb Bld. 0.045 0.041 Bld. Bld. Sr 0.743 0.637 0.691 0.396 0.48 Y 23.97 51.52 42.39 25.53 29.65 Zr 37.7 35.3 42.6 17.33 31.6 Nb 0.0048 0.051 0.083 0.049 0.046 Sb Bld. Bld. Bld. Bld. Bld. Cs Bld. Bld. Bld. Bld. Bld. Ba 0.292 0.35 0.262 0.242 0.197 La 0.0076 0.0042 Bld. Bld. Bld. Ce 0.162 0.18 0.15 0.079 0.09 Pr 0.075 0.079 0.086 0.0375 0.0414 Nd 0.73 0.84 0.55 0.476 0.642 Sm 1.46 0.99 0.89 0.82 1.08 Eu 0.966 0.783 0.717 0.493 0.617 Gd 3.68 2.71 2.36 1.6 2.06 Tb 0.804 0.839 0.793 0.565 0.682 Dy 5.8 7.87 6.48 4.55 5.24 Ho 0.967 1.849 1.501 0.989 1.13 Er 2.1 5.91 4.6 2.54 3.04 Yb 0.92 6.19 4.9 2.07 2.33 Lu 0.058 0.844 0.633 0.238 0.254 Hf 0.493 0.282 0.46 0.311 0.495  	 118	Table 15 (Continued) Ta 0.0049 Bld. Bld. Bld. Bld. Pb 0.487 0.209 0.236 0.366 0.718 Th Bld. Bld. Bld. Bld. Bld. U Bld. Bld. Bld. Bld. Bld. P 140.3 236.8 244 261 205 Sc 31.39 119.4 117.1 68.1 54.84 V 129.8 118.7 124.2 155.1 159.3 Co 88 62.36 60.04 64.98 69.4 Cu Bld. 0.249 0.71 0.386 0.543 Zn 113.4 74.5 64.2 49.7 63.5 As 5.41 26 Bld. Bld. Bld.    	 119	Table 15 (Continued)  SLCX 47 Gt2 SLCX 47 Gt3 SLCX 47 Gt4 wt%    SiO2 41.01 40.25 40.95 TiO2 0.41 0.46 0.30 Al2O3 23.47 23.10 23.51 Cr2O3 0.05 0.03 0.04 FeO 14.12 13.58 13.96 MnO 0.35 0.32 0.31 MgO 16.64 16.37 16.88 CaO 5.25 5.22 5.23 Na2O 0.06 0.11 0.08 K2O 0.01 0.03 0.02 NiO   0.01 Total 101.35 99.46 101.30 ppm    Rb 0.052 0.066 Bld. Sr 0.581 0.629 0.707 Y 36.47 37.52 39.36 Zr 43.9 29.8 30.2 Nb 0.042 0.022 0.0259 Sb Bld. Bld. Bld. Cs Bld. Bld. Bld. Ba 0.317 0.417 0.403 La Bld. Bld. Bld. Ce 0.068 0.081 0.075 Pr 0.0414 0.0326 0.0351 Nd 0.54 0.58 0.445 Sm 0.97 0.91 0.94 Eu 0.662 0.605 0.646 Gd 2.54 2.1 2.29 Tb 0.828 0.724 0.753 Dy 6.19 6.19 6.63 Ho 1.386 1.381 1.499 Er 3.87 4.14 4.3 Yb 2.87 3.68 3.65 Lu 0.322 0.406 0.44 Hf 0.706 0.594 0.565  	 120	Table 15 (Continued) Ta Bld. Bld. Bld. Pb 0.746 0.886 1.314 Th Bld. Bld. Bld. U Bld. Bld. Bld. P 197 341 199 Sc 75.4 73.9 79.1 V 174.8 159.3 166 Co 70.64 66.49 70.39 Cu 3.27 3.58 3.4 Zn 65.6 63.2 69.8 As Bld. Bld. 105 	 121	Table 16 Ages (Ma) of 4 Zircons with Correlated Drilling Depth Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 0 14.14 1374.87 6.25 12.27 585.60 3.89 17.38 979.82 6.65 0.00 1513.49  0.05 12.26 1449.09 7.00 13.13 511.61 3.99 14.39 1045.02 6.57 0.00 3159.25  0.1 12.10 1263.55 7.19 13.94 497.81 4.58 11.87 1052.17 6.28 11.67 3569.70 0.52 0.15 14.13 1091.43 6.70 15.56 484.99 3.94 14.12 883.81 6.04 9.90 3819.83 0.64 0.2 12.80 1199.41 6.27 16.30 460.58 3.83 15.47 848.76 6.28 13.05 3345.78 0.58 0.25 13.67 1036.98 5.47 13.84 499.24 4.12 12.66 875.53 6.76 12.89 3447.75 0.59 0.3 13.61 964.39 5.89 15.55 497.36 3.69 11.46 875.62 6.67 12.35 3324.70 0.48 0.35 13.30 932.63 5.42 14.71 488.43 3.92 11.93 847.81 6.67 10.86 3444.83 0.52 0.4 14.08 914.37 5.70 15.54 483.21 3.51 11.34 732.38 5.74 12.46 3176.11 0.61 0.45 12.81 911.95 5.62 14.19 493.67 3.84 13.08 625.58 5.11 12.05 3016.20 0.73 0.5 13.79 868.23 4.90 14.39 487.88 3.37 14.54 592.24 5.94 12.48 2944.37 1.10 0.55 14.84 822.76 5.02 12.50 510.99 3.28 14.45 607.67 5.56 17.21 2451.59 1.33 0.6 13.14 904.13 4.75 14.61 466.98 3.55 13.76 639.07 6.03 13.07 2969.56 1.61 0.65 15.67 853.10 5.10 13.92 437.98 3.33 11.31 671.17 6.64 12.12 2700.41 1.46 0.7 11.50 869.12 4.94 14.61 393.66 3.15 11.18 609.25 6.09 13.46 2053.68 1.47 0.75 14.50 750.48 4.41 16.13 427.28 3.53 12.38 587.85 5.98 15.47 1849.03 1.60 0.8 13.54 799.21 4.94 14.07 421.75 3.44 13.53 565.78 6.54 15.58 1827.00 1.51 0.85 13.10 811.38 4.12 15.83 406.32 3.05 14.13 509.78 6.56 14.23 2010.14 1.47 0.9 13.74 777.24 4.11 15.11 435.63 3.34 12.66 540.46 6.77 15.50 1983.87 1.50 0.95 12.45 727.85 4.34 15.46 439.97 3.12 10.57 492.57 5.73 12.96 1788.60 1.49 1 11.28 636.31 4.26 14.83 472.31 3.14 11.83 488.39 6.46 16.96 1510.06 1.31 1.05 14.95 515.93 3.93 13.44 512.74 3.19 11.94 516.32 6.02 14.54 1510.02 1.36 1.1 12.73 506.74 4.41 13.64 462.76 2.95 11.06 475.09 5.68 12.70 1556.25 1.46 1.15 16.44 490.19 4.22 14.76 453.00 2.96 9.53 431.52 5.59 14.41 1449.45 1.38 1.2 13.91 542.52 4.55 14.50 453.27 3.24 14.43 414.22 5.85 13.82 1348.74 1.30 *Ages are measured isotopic 206Pb/238U dates corrected for common lead, see detailed instruction in Chapter Ⅲ. Data are as reported by the instrument.    	 122	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 1.25 13.06 528.86 4.93 16.81 430.55 2.90 11.53 435.17 5.62 14.83 1315.24 1.02 1.3 12.40 503.33 4.55 14.20 471.84 2.89 13.44 437.72 5.57 12.68 1363.54 1.16 1.35 13.11 412.26 4.31 13.28 461.96 2.79 12.61 490.24 5.22 12.74 1210.11 1.14 1.4 12.20 409.43 4.02 14.93 428.29 2.83 12.16 478.95 6.01 16.90 1112.34 1.02 1.45 13.69 372.61 4.13 13.77 437.95 2.56 12.02 469.84 5.34 11.80 1208.41 0.84 1.5 13.42 379.21 5.44 13.46 415.42 2.67 13.77 453.11 5.48 12.56 1141.86 0.60 1.55 12.98 365.43 4.53 15.79 377.14 2.65 11.04 451.49 4.83 13.00 1053.62 0.86 1.6 14.33 353.85 4.84 13.64 410.44 2.52 11.61 426.15 4.33 15.89 959.61 0.81 1.65 13.57 352.93 5.06 13.81 394.63 2.66 14.31 415.89 5.38 17.31 924.44 0.84 1.7 13.67 334.91 5.16 13.75 391.94 2.50 11.32 463.56 5.22 15.67 946.22 0.78 1.75 13.73 348.55 6.03 13.91 346.26 2.58 13.48 453.94 5.22 14.63 905.17 0.53 1.8 16.41 352.00 4.65 15.86 350.24 2.74 10.71 507.48 5.02 16.61 865.50 0.62 1.85 13.19 354.67 3.79 16.45 384.66 2.35 11.43 526.80 5.30 14.07 899.87 0.54 1.9 13.33 313.15 6.46 12.37 418.34 2.88 12.12 548.00 4.32 13.12 910.68 0.51 1.95 14.57 304.73 3.82 15.44 373.01 2.46 13.83 567.95 5.82 18.70 909.19 0.48 2 13.55 306.34 5.19 13.44 349.57 2.54 11.40 610.25 5.82 9.87 1059.87 0.48 2.05 14.68 277.71 4.25 15.68 315.73 2.30 12.06 598.78 5.24 14.88 922.58 0.36 2.1 12.63 322.46 3.76 14.79 326.46 2.52 12.33 607.58 5.02 12.94 921.99 0.30 2.15 14.93 321.03 4.18 15.47 332.58 2.42 13.98 659.62 4.95 11.79 924.38 0.40 2.2 16.18 329.31 3.86 13.45 353.05 2.51 11.97 733.99 4.95 12.11 998.10 0.32 2.25 13.38 337.82 3.83 15.54 338.74 2.46 14.64 722.81 4.71 13.23 1016.17 0.27 2.3 14.88 318.47 3.98 14.05 357.64 2.22 12.39 765.02 4.96 10.65 1156.77 0.26 2.35 12.63 319.33 4.11 15.16 361.19 2.26 15.36 801.64 4.96 12.12 1204.96 0.23 2.4 13.69 303.29 3.44 14.61 372.91 2.42 11.14 889.80 4.72 11.15 1099.00 0.24 2.45 15.11 281.58 3.61 14.22 360.27 2.26 12.01 782.25 4.75 12.54 1159.89 0.26    	 123	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 2.5 15.68 294.79 3.83 11.55 329.53 2.29 12.51 795.72 5.99 13.06 1068.57 0.24 2.55 12.69 312.23 3.93 16.65 338.74 2.06 12.54 808.17 6.01 13.06 1089.21 0.28 2.6 12.24 290.59 2.85 14.83 347.81 2.19 15.21 818.93 5.28 6.67 1197.09 0.25 2.65 13.26 266.31 3.50 15.05 342.78 2.17 11.92 874.37 6.00 8.77 1307.90 0.20 2.7 13.92 282.92 3.30 13.73 342.88 2.09 13.13 821.66 6.24 9.60 1302.06 0.21 2.75 14.53 293.74 3.21 14.14 341.21 2.36 14.60 854.48 5.22 10.96 1267.23 0.22 2.8 16.43 282.28 3.34 13.69 358.62 2.22 13.89 933.51 5.75 7.75 1211.69 0.19 2.85 14.00 286.20 3.07 13.98 361.92 2.03 13.13 979.11 5.73 10.03 1074.60 0.21 2.9 12.16 300.39 2.47 15.71 352.23 2.02 12.37 1001.86 5.79 8.96 1113.07 0.15 2.95 13.34 275.08 2.55 13.09 363.29 2.01 13.81 989.39 6.01 10.26 842.64 0.33 3 16.35 293.07 2.80 13.12 342.09 1.96 15.92 982.21 6.22 15.76 783.77 0.46 3.05 11.86 333.50 2.28 12.65 329.09 2.13 11.64 1041.72 6.17 12.31 804.81 0.54 3.1 15.70 287.11 2.32 13.65 298.02 1.89 15.10 933.00 6.51 9.95 782.38 0.47 3.15 14.65 286.01 2.27 13.45 292.04 2.05 13.50 980.38 6.24 12.19 738.84 0.34 3.2 13.45 297.17 2.12 14.38 291.35 2.12 14.64 1008.22 6.69 13.36 781.28 0.41 3.25 12.66 295.59 2.02 13.73 295.83 1.99 13.09 1066.92 6.30 8.95 712.56 0.40 3.3 14.28 303.52 1.63 14.09 266.43 1.98 13.67 1039.05 7.49 12.46 631.11 0.46 3.35 11.55 297.27 1.53 15.48 240.84 1.91 15.69 1000.22 7.69 13.05 633.58 0.59 3.4 11.57 307.19 1.76 19.20 237.33 1.96 11.91 1038.24 8.64 11.35 611.91 0.66 3.45 12.08 315.89 1.58 14.98 274.40 1.85 12.92 1005.48 7.93 8.95 559.62 0.69 3.5 15.51 322.59 1.70 13.88 281.88 1.98 12.91 1000.33 7.80 12.82 512.43 0.78 3.55 13.04 333.44 1.52 14.86 260.14 2.07 13.53 1003.53 9.34 15.61 545.91 0.92 3.6 12.40 347.28 1.47 17.29 265.34 1.78 14.02 1034.18 9.02 14.21 547.59 1.01 3.65 12.09 329.05 1.44 18.00 278.09 2.13 13.96 1042.88 7.91 12.71 530.36 0.89 3.7 12.57 317.40 1.35 14.99 341.24 1.93 12.03 1065.99 8.52 14.20 495.11 1.00    	 124	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 3.75 13.47 323.71 1.39 15.23 361.72 1.96 13.71 1030.17 7.85 16.68 454.87 1.08 3.8 14.27 327.62 1.38 13.81 372.39 1.89 10.34 1052.19 8.84 13.45 440.42 1.04 3.85 13.44 327.40 1.26 14.88 345.44 1.91 13.76 957.55 7.76 13.37 446.54 1.05 3.9 13.29 315.59 1.24 14.32 362.77 1.96 12.08 977.83 9.60 13.47 411.13 1.06 3.95 11.88 318.39 1.37 15.24 380.55 1.94 14.01 943.23 7.80 13.00 417.51 1.08 4 13.85 339.08 1.27 12.45 411.52 1.99 13.10 1029.66 9.51 14.86 444.62 1.10 4.05 13.41 338.75 1.38 12.81 389.89 1.94 14.23 1008.34 8.06 17.94 444.45 1.07 4.1 13.19 337.73 1.42 14.70 370.12 1.84 11.76 1105.48 9.00 15.89 471.34 0.99 4.15 14.32 333.20 1.48 16.38 401.14 1.89 14.91 1048.19 8.24 15.53 451.57 0.92 4.2 12.26 313.00 1.58 13.80 427.34 1.88 15.08 1181.92 9.25 12.90 444.83 1.02 4.25 14.62 295.63 1.60 12.55 429.35 1.68 9.92 1289.82 8.07 14.93 452.86 0.93 4.3 14.03 339.55 1.57 15.07 397.17 1.72 13.14 1104.87 8.74 11.65 437.11 0.84 4.35 15.34 331.05 1.54 14.88 422.89 1.79 12.79 1109.37 7.42 11.54 432.58 0.84 4.4 12.28 349.07 1.70 13.46 443.32 1.80 13.65 1102.59 9.81 10.95 411.25 0.68 4.45 12.65 323.21 1.54 12.61 433.79 1.57 11.54 1166.65 8.58 12.24 378.35 0.77 4.5 11.10 315.77 1.69 13.83 409.08 1.62 12.27 1067.98 9.78 12.81 388.95 0.79 4.55 15.23 305.24 1.56 14.95 417.35 1.69 12.52 1038.21 7.70 12.44 379.06 0.71 4.6 12.89 327.19 1.56 13.55 465.75 1.62 13.24 1049.63 7.66 13.56 378.54 0.69 4.65 12.60 335.23 1.65 15.89 463.90 1.66 14.51 1130.79 7.58 12.24 385.13 0.74 4.7 15.42 305.46 1.59 13.42 501.15 1.66 12.09 1211.75 7.65 13.03 349.34 0.74 4.75 14.07 334.49 1.44 12.96 452.69 1.57 12.07 1182.29 7.54 14.47 353.27 0.61 4.8 13.43 344.27 1.45 15.19 426.96 1.65 11.12 1118.95 8.02 13.57 384.24 0.65 4.85 13.29 341.05 1.35 12.32 454.24 1.67 13.03 1053.91 8.77 10.60 379.10 0.74 4.9 12.42 342.81 1.36 12.50 433.81 1.60 12.31 1094.71 8.33 13.62 340.01 0.72 4.95 13.72 361.21 1.41 11.42 394.41 1.68 15.01 1105.08 7.72 13.64 338.46 0.60    	 125	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 5 12.08 350.88 1.41 13.33 355.92 1.63 11.85 1220.00 8.15 13.22 351.32 0.59 5.05 11.43 332.49 1.47 12.61 347.01 1.74 12.51 1191.20 8.03 12.94 358.82 0.61 5.1 12.63 313.77 1.48 15.79 341.64 1.69 14.91 1202.92 8.30 13.82 343.59 0.59 5.15 13.43 304.11 1.58 16.61 364.28 1.65 11.54 1306.70 8.06 11.87 350.04 0.57 5.2 13.07 309.74 1.79 14.15 399.32 1.67 12.76 1251.95 7.41 12.89 339.25 0.61 5.25 14.70 345.64 1.63 12.11 386.05 1.67 13.43 1205.31 7.31 14.02 330.80 0.64 5.3 13.27 364.37 1.56 13.43 377.12 1.71 13.01 1192.72 6.54 18.58 316.51 0.74 5.35 13.64 362.51 1.51 16.54 345.22 1.67 12.47 1216.36 6.99 11.54 329.67 0.74 5.4 12.93 342.30 1.52 12.80 365.40 1.70 10.30 1216.68 7.01 12.69 313.77 0.81 5.45 13.81 325.23 1.48 14.34 356.64 1.61 14.12 1110.86 7.28 13.86 296.09 0.87 5.5 13.01 350.10 1.61 15.56 349.30 1.79 11.59 1171.99 7.78 11.05 288.90 0.95 5.55 12.12 328.35 1.53 13.82 371.70 1.69 12.33 1075.68 7.51 14.69 294.24 1.00 5.6 13.35 303.11 1.51 15.32 377.50 1.66 15.93 1124.48 6.79 11.37 281.54 1.00 5.65 15.25 294.98 1.61 14.36 412.38 1.63 13.89 1263.28 6.98 13.91 259.25 1.06 5.7 13.82 295.21 1.47 13.13 417.98 1.59 10.70 1322.90 7.20 14.35 276.83 1.11 5.75 13.56 303.71 1.56 15.50 393.99 1.64 12.51 1232.36 7.43 15.13 283.99 1.19 5.8 13.20 320.29 1.62 14.29 412.53 1.67 13.26 1258.52 7.89 12.13 270.84 1.16 5.85 12.83 328.41 1.61 14.36 417.29 1.57 13.24 1282.47 7.05 13.80 251.93 1.17 5.9 14.42 319.68 1.58 15.06 377.96 1.58 14.19 1313.37 7.74 14.10 273.03 1.21 5.95 12.36 291.58 1.46 13.88 407.32 1.54 12.22 1396.93 6.99 12.65 258.10 1.03 6 13.89 301.28 1.52 12.12 388.61 1.64 12.68 1339.81 7.82 15.59 251.96 1.08 6.05 13.88 303.21 1.34 13.43 373.48 1.55 12.88 1302.72 6.90 12.38 252.59 1.03 6.1 12.33 321.60 1.31 15.46 359.62 1.57 10.98 1308.89 7.29 12.17 238.01 1.00 6.15 12.59 376.18 1.37 14.48 393.44 1.55 11.38 1215.33 6.59 15.21 214.38 1.10 6.2 11.15 351.26 1.33 14.65 396.62 1.64 11.41 1132.83 6.97 12.20 203.26 1.14    	 126	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 6.25 14.44 343.10 1.34 12.54 411.47 1.54 15.44 1071.54 6.37 14.78 211.53 1.21 6.3 13.04 348.86 1.29 13.21 402.21 1.58 10.96 1186.82 6.73 13.28 222.41 1.31 6.35 11.90 330.71 1.36 14.65 381.16 1.49 12.56 1061.42 6.24 13.55 224.67 1.43 6.4 12.85 296.19 1.42 13.59 386.00 1.51 14.83 998.70 5.94 14.40 205.78 1.54 6.45 14.27 292.80 1.45 15.24 367.07 1.53 14.33 1004.16 5.57 14.27 207.98 1.62 6.5 12.25 296.10 1.49 11.64 395.77 1.57 13.35 920.30 5.23 13.33 206.01 1.55 6.55 13.37 296.67 1.58 13.94 345.38 1.56 17.29 831.15 5.60 14.66 199.95 1.45 6.6 12.38 287.48 1.59 14.72 315.69 1.55 16.75 841.07 4.71 15.42 190.50 1.57 6.65 13.59 293.49 1.66 15.35 319.00 1.52 18.69 815.36 4.86 14.49 206.04 1.36 6.7 14.10 283.54 1.55 14.21 313.48 1.63 17.06 832.57 4.48 13.04 199.32 1.52 6.75 15.28 266.15 1.64 13.43 316.29 1.46 17.79 882.81 5.01 16.10 195.86 1.34 6.8 12.62 265.91 1.62 15.27 302.48 1.49 15.75 879.63 4.26 12.79 200.67 1.76 6.85 14.05 268.57 1.57 17.38 312.03 1.54 17.54 776.44 3.99 14.15 178.66 1.61 6.9 11.96 266.97 1.67 15.09 338.92 1.58 18.63 740.65 4.14 14.58 176.80 1.51 6.95 14.72 264.87 1.65 13.70 314.67 1.54 18.75 687.44 4.21 15.09 177.25 1.38 7 14.77 269.23 1.74 15.38 286.59 1.55 24.34 633.99 3.73 11.09 178.70 1.62 7.05 14.16 271.86 1.63 13.14 304.36 1.62 23.43 693.01 3.99 16.64 161.15 1.50 7.1 13.36 270.16 1.62 14.67 292.31 1.50 21.60 758.31 3.59 13.49 167.34 1.63 7.15 12.58 264.87 1.66 15.52 268.39 1.58 20.42 794.29 3.72 15.38 171.83 1.83 7.2 12.41 288.53 1.76 16.79 279.88 1.50 20.92 776.77 3.79 14.23 166.96 1.71 7.25 12.77 264.58 1.66 14.06 290.46 1.51 21.13 724.92 3.54 17.13 160.28 1.80 7.3 15.95 260.20 1.66 17.85 293.56 1.50 21.88 720.18 3.48 13.42 173.35 1.72 7.35 11.32 263.60 1.70 14.49 314.15 1.59 20.20 717.36 3.90 12.08 184.48 1.61 7.4 14.04 252.36 1.67 13.67 298.34 1.54 26.15 701.83 3.60 15.14 183.51 1.73 7.45 13.62 271.46 1.57 14.34 291.12 1.49 20.95 767.40 3.61 14.58 177.09 1.54    	 127	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 7.5 13.09 272.72 1.49 13.59 297.12 1.48 24.10 741.22 3.89 13.52 175.62 1.83 7.55 13.82 267.24 1.74 14.72 289.21 1.49 21.82 780.79 3.72 13.27 172.53 1.58 7.6 11.58 257.55 1.52 15.70 290.14 1.53 23.36 840.56 3.70 15.29 159.97 1.85 7.65 15.02 252.42 1.53 15.34 316.45 1.67 18.58 935.14 3.83 14.53 154.81 1.86 7.7 12.29 269.76 1.57 12.83 310.33 1.55 19.05 902.36 3.84 13.27 154.17 1.89 7.75 15.31 260.04 1.60 13.82 296.43 1.46 18.18 907.82 3.78 16.31 163.61 1.69 7.8 11.88 273.54 1.63 15.34 301.17 1.66 22.33 906.74 3.87 13.64 145.63 2.03 7.85 14.96 257.29 1.61 13.54 302.13 1.53 21.13 1050.55 3.73 14.99 135.91 1.90 7.9 14.45 268.35 1.56 14.80 290.11 1.53 18.14 1158.59 3.61 16.02 140.27 1.96 7.95 11.59 290.60 1.50 14.59 290.40 1.54 17.08 1126.30 3.68 14.20 138.45 1.65 8 12.24 293.30 1.53 15.18 283.57 1.52 17.58 1132.44 3.36 20.11 137.98 1.63 8.05 12.14 290.87 1.46 15.36 285.26 1.55 16.25 1161.48 3.42 16.31 137.36 2.04 8.1 14.63 261.02 1.58 14.71 269.25 1.46 16.80 1156.99 3.44 18.99 144.28 1.66 8.15 13.45 265.69 1.47 16.85 254.82 1.50 18.99 1129.81 3.22 16.22 157.05 1.87 8.2 12.74 273.12 1.44 15.30 275.53 1.61 21.46 1168.56 3.26 17.21 166.68 1.76 8.25 13.26 270.48 1.40 15.92 287.67 1.55 19.81 1247.57 3.11 15.32 166.53 1.61 8.3 13.22 292.19 1.49 15.58 296.42 1.56 18.99 1273.41 3.07 18.83 170.61 1.16 8.35 12.91 289.50 1.35 14.10 291.27 1.46 21.34 1292.97 2.96 17.94 165.74 1.41 8.4 12.09 286.13 1.40 15.74 284.51 1.61 20.09 1319.04 2.79 15.86 172.93 1.49 8.45 12.89 268.20 1.43 14.25 286.17 1.64 20.63 1310.50 2.78 18.88 146.24 1.39 8.5 13.62 266.44 1.40 11.70 270.38 1.50 24.24 1169.22 2.68 16.87 160.34 1.35 8.55 13.97 262.72 1.47 14.74 263.40 1.46 24.80 1138.25 2.60 15.11 132.32 1.45 8.6 12.72 272.60 1.44 15.68 254.02 1.49 26.83 1118.10 2.65 21.85 135.03 1.20 8.65 14.86 250.40 1.44 14.12 259.19 1.42 24.11 1114.78 2.49 22.12 144.86 0.96 8.7 11.96 249.15 1.43 15.43 263.45 1.44 25.55 1027.92 2.44 12.01 158.44 1.11    	 128	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 8.75 13.57 243.14 1.47 14.80 261.85 1.50 27.72 950.66 2.31 26.45 148.61 1.06 8.8 13.58 235.29 1.47 17.25 260.35 1.56 32.19 934.84 2.23 18.12 158.52 1.04 8.85 12.09 230.23 1.33 14.91 283.74 1.51 30.34 981.09 2.22 14.55 149.79 1.07 8.9 14.50 215.22 1.43 13.52 270.83 1.59 34.09 946.13 2.14 19.68 145.70 1.05 8.95 12.84 228.89 1.47 14.12 253.27 1.65 29.34 1004.86 2.04 15.57 144.81 1.11 9 12.56 231.89 1.49 14.35 275.04 1.45 34.48 916.73 2.00 19.90 136.93 1.23 9.05 14.03 228.12 1.43 14.21 294.32 1.61 37.29 877.69 1.94 13.40 146.95 1.30 9.1 15.65 228.86 1.45 13.43 276.73 1.52 38.51 806.94 1.82 17.84 155.46 1.25 9.15 14.79 232.76 1.53 15.37 268.63 1.47 36.00 753.93 1.83 16.84 153.49 1.59 9.2 13.45 253.10 1.29 15.00 285.53 1.48 45.59 647.97 1.77 16.62 149.21 1.46 9.25 13.44 247.24 1.45 15.40 282.24 1.49 40.73 683.83 1.87 15.04 159.84 1.69 9.3 11.86 247.77 1.39 12.99 271.07 1.50 47.93 580.63 1.70 11.03 145.69 1.24 9.35 13.44 235.56 1.51 15.55 264.68 1.51 62.43 515.53 1.62 15.02 137.47 1.63 9.4 11.67 233.58 1.49 13.16 261.63 1.48 55.39 544.82 1.68 14.57 142.24 1.42 9.45 13.91 215.04 1.38 14.44 234.86 1.63 62.97 511.95 1.56 14.60 146.87 1.43 9.5 14.61 206.59 1.61 15.34 238.14 1.64 57.47 532.95 1.52 11.59 159.68 1.53 9.55 14.94 209.82 1.47 15.15 237.22 1.61 63.22 497.18 1.57 13.69 146.75 1.45 9.6 11.87 219.01 1.45 16.19 252.82 1.55 66.33 491.79 1.50 13.78 150.67 1.65 9.65 12.44 210.46 1.56 13.73 266.62 1.55 66.20 494.12 1.45 11.72 151.95 1.25 9.7 12.93 198.17 1.40 15.97 256.66 1.63 61.85 522.26 1.47 16.38 145.81 1.29 9.75 13.59 188.80 1.63 12.63 291.80 1.55 65.36 497.48 1.38 15.74 161.04 1.50 9.8 13.39 193.20 1.39 13.92 264.94 1.61 72.79 480.55 1.32 10.97 149.18 1.43 9.85 13.87 197.95 1.58 13.48 233.62 1.79 62.84 479.81 1.32 13.87 163.75 1.37 9.9 14.67 201.59 1.48 17.46 223.03 1.56 69.00 446.01 1.35 18.70 158.59 1.50 9.95 14.18 197.94 1.45 15.13 245.74 1.70 72.74 418.25 1.28 16.26 166.54 1.66    	 129	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 10 12.00 205.35 1.62 13.24 243.79 1.78 79.43 408.71 1.29 14.98 164.70 1.60 10.05 13.66 199.59 1.36 12.20 240.92 1.73 77.36 408.32 1.23 10.28 173.30 1.44 10.1 13.18 184.49 1.68 50.37 238.01 1.76 79.66 418.63 1.26 17.87 162.81 1.86 10.15 15.76 184.75 1.51 14.12 230.39 1.74 75.37 431.69 1.27 15.37 192.27 1.77 10.2 15.46 179.72 1.65 14.56 233.86 1.57 81.72 431.44 1.30 14.57 194.87 1.67 10.25 16.89 183.87 1.55 16.67 224.43 1.86 72.65 467.58 1.30 11.81 190.63 1.84 10.3 14.33 190.01 1.60 14.28 246.95 1.64 72.56 462.34 1.29 15.02 183.35 2.11 10.35 16.90 183.04 1.58 14.13 219.00 1.98 74.71 445.55 1.24 14.04 210.33 2.12 10.4 17.62 192.69 1.82 13.39 210.53 1.58 85.61 428.86 1.33 14.97 210.13 2.26 10.45 20.15 198.64 1.70 14.59 188.17 1.53 81.61 463.40 1.20 12.66 221.67 2.03 10.5 17.34 213.54 1.83 16.82 190.61 1.67 78.57 466.42 1.26 15.70 235.93 2.31 10.55 20.42 215.42 1.72 15.30 198.09 1.67 81.50 439.07 1.14 14.69 251.98 2.28 10.6 20.38 204.03 1.82 16.58 194.60 1.75 82.26 427.70 1.21 15.97 259.74 2.58 10.65 20.67 193.03 1.83 13.65 218.20 1.84 80.03 428.00 1.19 18.42 256.01 2.67 10.7 25.16 187.04 2.39 15.00 210.21 1.73 90.00 406.34 1.22 15.44 281.01 2.54 10.75 25.22 195.30 2.02 14.24 201.69 1.68 84.90 436.96 1.23 19.21 258.14 2.54 10.8 27.21 200.86 1.91 15.58 198.16 1.70 82.60 452.23 1.22 18.90 237.59 2.69 10.85 29.55 216.75 2.33 15.31 200.28 1.93 81.24 455.50 1.20 19.73 247.66 2.59 10.9 28.47 219.27 2.22 14.22 190.66 1.71 83.11 452.50 1.18 13.57 248.56 2.36 10.95 30.86 201.81 2.26 14.98 176.54 1.85 72.87 446.24 1.19 20.77 224.58 2.42 11 35.97 192.39 2.04 17.82 185.64 1.76 90.46 383.31 1.13 17.41 240.48 2.06 11.05 44.89 202.67 2.04 14.79 213.24 1.92 84.31 385.24 1.09 21.65 232.71 2.81 11.1 35.32 230.48 2.12 14.45 228.95 1.90 96.05 394.27 1.18 15.69 229.70 2.29 11.15 40.73 223.67 2.06 16.35 214.98 1.90 76.40 438.59 1.17 15.41 214.78 2.44 11.2 38.41 219.74 2.01 14.36 239.47 1.72 82.84 422.79 1.16 16.90 217.85 2.52    	 130	Table 16 (Continued) Depth Zircon1 Zircon2 Zircon3 Zircon4 (µm) Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th Age U ppm U/Th 11.25 50.30 205.10 1.67 13.21 237.58 1.83 88.24 428.85 1.20 12.04 236.43 2.48 11.3 45.43 216.20 1.99 12.92 232.81 1.78 86.38 452.84 1.16 12.86 242.18 2.52 11.35 51.17 214.11 1.82 15.13 213.91 1.71 80.15 469.44 1.22 15.75 237.02 2.53 11.4 51.70 219.83 1.73 15.94 202.00 1.58 74.72 474.54 1.21 14.69 243.91 2.52 11.45 50.74 215.69 1.82 15.38 219.95 1.72 84.78 446.22 1.17 15.99 260.11 3.11 11.5 58.34 210.41 1.57 13.93 233.35 1.77 82.16 470.57 1.19 15.04 270.10 2.63 11.55 56.65 219.65 1.59 14.86 256.85 1.81 79.25 486.15 1.23 14.17 263.74 2.06 11.6 57.71 236.76 1.47    79.80 514.25 1.28 16.67 240.44 2.15 11.65 62.55 216.09 1.54    72.46 550.63 1.37 23.87 254.64 1.94 11.7 66.53 213.33 1.54    67.47 560.01 1.32 19.31 302.06 1.65 11.75 71.29 225.40 1.53    75.04 516.83 1.31 16.17 315.17 1.48 11.8 69.12 247.36 1.38    67.89 516.28 1.25 15.65 279.82 1.09 11.85 72.40 241.33 1.31    83.54 484.18 1.25 16.02 266.53 1.19 11.9 79.62 250.95 1.33    79.75 514.62 1.23 14.49 270.69 1.15 11.95 76.40 286.33 1.22    71.03 565.87 1.22 21.52 269.33 1.39 12 73.44 292.66 1.27    74.71 550.28 1.28 21.07 275.62 1.09 12.05 82.24 292.93 1.17    69.16 556.98 1.21 19.16 271.53 1.10 12.1 74.48 309.70 1.19    75.90 521.60 1.22 22.39 264.79 0.84 12.15 75.04 315.81 1.16       22.06 270.05 1.21 12.2          20.44 345.17 0.92 12.25 76.87         19.21 370.39 1.27    	 131	Table 17 Mean Age of Four Zircons   Zircon1 Zircon2 Zircon3 rim Zircon3 core Zircon4 Mean (Ma) 13.4 14.5 12.9 80.8 14.2 2SE abs. 0.2 0.2 0.2 2.0 0.3 2SD abs. 2.1 2.6 2.6 10.1 4.7 2SD % 15.7 17.7 19.9 12.4 33.2 2SE % 1.1 1.2 1.8 2.5 2.2 Depth range (µm) 0-10 0-11.5 0-6.25 10-11.25 0-12.25    	 132	Table 18 LA-ICP-MS Depth Profiling Trace Element Concentrations for Zircon1 (SLCX 47) Depth                  (µm) Ti Y Nb La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf 0.00                  0.28 30.49 2854.47 2.11 Bdl. 0.77 3.74 4.78 Bdl. 36.97 13.62 258.61 102.19 537.19 112.37 1193.77 193.28 12080.32 0.55 0.01 3675.81 2.46 Bdl. 0.90 Bdl. 5.59 Bdl. 67.32 17.93 349.87 124.99 562.54 128.60 1234.62 192.70 16582.12 0.83 0.01 2476.66 Bdl. Bdl. Bdl. 3.64 Bdl. Bdl. 35.89 9.91 111.60 69.06 320.09 77.24 898.55 129.36 12668.95 1.11 0.01 2527.25 5.46 Bdl. 4.98 Bdl. Bdl. Bdl. 26.66 6.63 238.75 80.24 562.32 90.16 892.56 164.04 15618.49 1.38 0.01 1612.12 2.19 Bdl. 0.80 Bdl. 14.96 1.30 21.44 5.33 89.99 49.97 289.89 65.91 557.41 104.90 11748.83 1.66 0.01 1069.55 Bdl. Bdl. Bdl. 3.19 Bdl. Bdl. 27.79 1.44 170.18 35.25 163.22 56.62 409.74 71.19 9660.35 1.93 0.01 1332.23 2.53 Bdl. Bdl. Bdl. Bdl. Bdl. 19.78 12.29 131.50 35.28 254.91 85.16 695.98 106.16 14779.37 2.21 56.42 1143.51 Bdl. Bdl. 0.70 Bdl. Bdl. Bdl. 52.54 6.22 99.79 40.84 236.38 48.47 392.57 73.09 10932.00 2.49 0.01 1123.14 1.72 Bdl. 1.89 3.11 23.54 2.05 6.74 15.36 66.05 50.57 135.08 24.88 457.82 72.29 10490.43 2.76 0.01 1391.36 Bdl. Bdl. Bdl. 7.64 Bdl. Bdl. 16.55 24.00 63.70 35.67 227.34 57.27 516.99 99.60 13373.83 3.04 0.01 1482.93 Bdl. Bdl. 1.82 Bdl. Bdl. Bdl. 19.47 14.12 136.26 51.05 222.81 67.38 584.56 102.67 13141.46 3.32 0.01 1295.29 1.87 Bdl. 2.75 Bdl. Bdl. 1.12 58.81 13.71 123.50 39.91 340.69 63.33 401.59 66.60 10046.67 3.59 0.01 1285.03 Bdl. Bdl. 3.37 Bdl. 4.19 Bdl. 28.82 10.45 90.78 55.26 197.81 63.18 345.87 87.77 11112.00 3.87 69.54 1756.36 Bdl. Bdl. 4.28 4.25 5.33 1.39 18.30 9.48 179.32 56.44 224.96 66.16 532.31 111.39 11130.98 4.14 0.01 1789.46 Bdl. Bdl. 3.71 4.62 17.32 1.50 14.87 32.86 145.74 68.53 391.08 71.70 683.59 120.64 11522.73 4.42 61.83 1630.94 Bdl. Bdl. 1.52 15.13 18.88 2.46 24.31 11.75 113.47 66.58 291.81 68.59 534.29 113.22 11064.11 4.70 0.01 2012.88 4.53 Bdl. 1.67 8.34 20.77 2.70 35.67 14.78 199.79 63.24 361.80 67.25 683.89 108.40 11399.24 4.97 0.01 2004.00 10.71 Bdl. 3.16 Bdl. 4.91 Bdl. 33.75 19.23 100.44 64.52 327.82 83.12 560.97 87.28 11495.94 5.25 0.01 1861.66 2.08 Bdl. 2.30 3.84 19.09 Bdl. 45.05 6.79 154.87 79.40 304.14 59.26 593.43 91.41 9923.32 5.53 0.01 1966.05 Bdl. Bdl. 1.65 16.58 10.28 1.34 61.74 12.79 172.93 62.43 241.75 67.89 622.85 98.37 10961.23 5.80 0.01 2026.38 2.27 Bdl. 1.68 12.68 Bdl. 2.72 35.91 22.32 125.75 56.83 276.80 76.03 612.33 108.92 9608.37 6.08 0.01 1726.89 Bdl. Bdl. 3.02 11.44 4.71 Bdl. 8.08 16.74 215.16 79.72 276.88 63.49 444.79 96.70 9584.90 6.35 35.57 1960.13 6.99 Bdl. 1.72 4.35 10.73 Bdl. 9.20 15.25 199.82 59.89 325.63 52.44 594.21 104.00 11032.28 6.63 0.01 2114.45 7.96 Bdl. 4.91 Bdl. 24.46 Bdl. 41.97 26.08 227.84 56.55 341.24 61.41 677.22 111.64 13027.82 *All concentrations in ppm. Bdl. = below detecting limit. Data are as reported by the instrument. 	 133	Table 18 (Continued) Depth                  (µm) Ti Y Nb La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf 6.91 0.01 2073.79 17.34 Bdl. 5.35 10.84 26.66 1.73 34.30 33.15 240.27 87.06 371.76 58.11 737.68 123.46 12908.30 7.18 0.01 2099.83 2.58 Bdl. 2.87 4.86 17.90 1.55 66.51 10.60 265.21 64.57 501.86 50.44 696.58 107.08 11773.82 7.46 0.01 1856.98 Bdl. Bdl. 1.66 4.23 Bdl. 2.69 53.33 12.89 149.44 98.93 319.27 64.35 445.67 103.14 10120.42 7.74 0.01 1924.67 Bdl. Bdl. 3.76 Bdl. 23.47 Bdl. 50.32 33.35 169.20 93.28 298.28 63.56 684.55 129.86 10761.96 8.01 0.01 1777.74 Bdl. Bdl. 2.51 4.26 5.21 Bdl. 67.00 27.75 269.14 87.72 417.48 60.56 570.18 105.02 10319.41 8.29 0.01 1948.13 4.43 Bdl. 0.82 4.20 15.38 Bdl. 87.91 18.21 283.35 68.37 315.56 75.86 555.65 94.68 10652.33 8.56 0.01 1955.49 2.45 Bdl. 1.82 4.66 11.36 Bdl. 43.81 20.16 150.09 61.26 310.59 51.01 562.94 100.05 8860.77 8.84 0.01 2333.38 6.66 Bdl. 3.71 6.35 Bdl. Bdl. 46.31 24.66 268.85 70.95 361.65 101.95 756.76 131.56 13270.99 9.12 0.01 2100.74 Bdl. Bdl. 2.88 4.93 Bdl. Bdl. 41.02 23.36 122.17 53.07 344.49 77.45 531.40 93.57 10977.73 9.39 0.01 1728.94 Bdl. Bdl. 4.35 Bdl. 10.85 Bdl. 41.84 17.33 123.80 54.96 232.87 45.86 409.65 65.11 9379.11 9.67 0.01 1530.26 5.22 Bdl. 1.94 Bdl. Bdl. 3.13 46.67 21.48 123.55 82.32 360.01 62.35 518.47 96.21 9312.24 9.95 41.81 1374.22 Bdl. Bdl. 3.95 Bdl. Bdl. 3.18 42.21 10.93 155.32 52.57 264.18 48.81 489.72 89.27 9198.68 10.22 0.01 2381.81 3.65 Bdl. Bdl. 7.03 8.48 Bdl. 21.79 36.10 244.38 75.00 404.92 89.59 570.24 96.85 14371.42 10.50 0.01 1315.16 Bdl. Bdl. 1.80 Bdl. 16.81 Bdl. 9.60 5.96 94.19 37.14 191.04 48.84 410.86 78.00 9631.90 10.77 0.01 1588.38 2.96 Bdl. 1.10 Bdl. 6.89 3.56 41.32 9.78 82.76 45.66 295.35 36.41 470.10 103.56 9872.63 11.05 0.01 1220.28 4.71 Bdl. 3.51 Bdl. Bdl. 1.42 18.79 15.56 52.68 32.85 299.05 34.77 301.38 91.52 7941.58 11.33 0.01 1452.35 5.53 Bdl. 4.12 Bdl. Bdl. Bdl. 55.12 18.26 85.01 66.92 306.98 44.21 399.36 100.18 10142.98 11.60 0.01 1680.98 9.46 Bdl. 7.06 6.14 7.35 1.90 88.08 10.42 176.43 69.39 228.77 64.05 500.49 104.08 9939.79 11.88 0.01 1379.12 4.95 Bdl. 7.40 4.84 Bdl. Bdl. 39.55 14.33 159.46 47.23 196.59 48.81 346.24 80.15 6536.77 12.16 0.01 2090.86 9.20 Bdl. 18.33 Bdl. Bdl. Bdl. 12.25 10.14 25.76 26.99 55.64 9.45 79.92 13.89 1421.04 12.43 0.01 1148.23 Bdl. Bdl. 17.37 Bdl. Bdl. Bdl. Bdl. Bdl. Bdl. Bdl. Bdl. Bdl. Bdl. 30.08 105.61    	 134	Table 19 LA-ICP-MS Depth Profiling Trace Element Concentrations for Zircon2 (SLCX 47) Depth                  (µm) Ti Y Nb La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf 0.00                  0.28 6979.80 2878.90 11.95 Bdl. Bdl. Bdl. 10.65 Bdl. 43.55 19.70 181.01 76.87 490.59 102.46 710.28 113.99 11786.43 0.55 256.85 1885.38 2.08 Bdl. 1.71 Bdl. Bdl. Bdl. 18.18 29.91 182.45 95.72 301.49 85.28 929.56 110.97 15184.24 0.83 443.83 2656.97 Bdl. Bdl. Bdl. Bdl. 25.50 Bdl. 31.27 19.29 246.54 109.79 384.01 87.83 898.11 130.29 13520.00 1.11 137.62 2269.19 Bdl. Bdl. 0.91 Bdl. 5.90 Bdl. 43.44 21.83 110.70 49.22 350.50 96.69 820.69 120.65 12714.33 1.38 0.03 1607.57 6.65 Bdl. 0.69 Bdl. Bdl. Bdl. 36.51 16.51 130.86 45.95 242.08 51.09 604.13 102.01 10080.45 1.66 147.54 2583.92 Bdl. Bdl. 0.96 Bdl. Bdl. Bdl. 51.24 14.75 227.74 76.72 382.84 58.66 659.47 134.12 17163.28 1.93 109.91 1369.15 Bdl. Bdl. 2.14 Bdl. 4.65 Bdl. 15.19 6.25 206.97 53.03 171.86 47.11 493.30 77.08 9864.85 2.21 0.03 1293.06 Bdl. Bdl. 4.02 Bdl. 17.45 Bdl. 42.76 4.40 178.84 35.20 281.19 55.53 483.29 68.12 9828.81 2.49 0.04 1378.27 3.48 Bdl. 2.88 8.25 4.70 Bdl. 19.19 9.47 143.06 91.55 234.13 32.95 321.96 56.42 9731.68 2.76 0.05 1971.80 6.30 Bdl. 3.48 19.95 5.67 Bdl. 23.17 17.14 106.30 67.93 321.66 67.79 559.23 76.30 11755.08 3.04 219.80 1448.10 Bdl. Bdl. 0.70 8.03 4.56 Bdl. 37.23 18.37 128.12 49.53 270.16 45.00 539.24 78.82 8668.72 3.32 110.90 1581.90 Bdl. Bdl. 0.70 Bdl. Bdl. Bdl. 18.69 16.91 101.88 61.26 251.65 42.81 447.05 73.66 8538.52 3.59 0.04 1425.52 1.88 Bdl. 2.34 8.98 15.26 2.26 53.98 10.24 101.25 42.54 292.57 39.63 377.19 51.28 9757.02 3.87 0.05 1296.36 Bdl. Bdl. Bdl. Bdl. 5.80 1.29 23.67 21.41 196.90 43.67 204.07 55.72 522.56 76.56 11461.10 4.14 267.07 1754.23 Bdl. Bdl. 0.83 Bdl. Bdl. Bdl. 35.47 10.94 228.96 72.76 265.71 86.05 571.11 121.26 9449.41 4.42 0.05 2243.85 3.87 Bdl. 2.41 9.32 10.50 2.33 25.71 17.62 233.62 49.84 419.03 102.27 680.26 127.29 10735.19 4.70 0.05 2774.72 2.11 Bdl. Bdl. 10.22 Bdl. Bdl. 84.48 21.22 181.79 101.20 458.85 85.12 755.86 133.88 10085.52 4.97 0.06 2961.12 Bdl. Bdl. Bdl. Bdl. 39.13 Bdl. 58.54 28.44 366.47 102.05 520.22 93.13 1053.05 190.92 11893.19 5.25 0.05 2601.51 Bdl. Bdl. 4.16 9.67 Bdl. Bdl. 53.14 36.41 152.48 63.72 353.71 80.32 652.13 85.94 8890.39 5.53 0.06 2437.47 4.75 Bdl. 2.98 11.56 6.48 Bdl. 52.83 26.06 303.22 97.80 444.19 77.34 693.02 104.09 12249.66 5.80 0.05 2053.38 6.02 Bdl. 0.84 Bdl. 32.91 Bdl. 58.17 29.43 211.88 87.48 319.73 51.26 695.15 107.90 8642.43 6.08 0.06 2595.08 7.27 Bdl. 1.02 11.86 13.25 Bdl. 124.30 15.55 387.75 87.16 516.74 91.16 945.39 155.74 11283.21 6.35 449.01 2627.89 4.27 Bdl. 0.90 10.49 Bdl. Bdl. 47.71 17.65 130.07 76.99 375.92 75.92 658.91 123.45 8994.53 6.63 0.07 3679.00 14.27 Bdl. 3.59 28.08 7.82 Bdl. 31.88 26.21 247.05 120.48 596.14 135.97 1020.16 149.99 12732.96 *All concentrations in ppm. Bdl. = below detecting limit. Data are as reported by the instrument. 	 135	Table 19 (Continued) Depth                  (µm) Ti Y Nb La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf 6.91 0.06 2491.43 Bdl. Bdl. 0.95 Bdl. 18.55 Bdl. 50.42 8.29 173.66 67.59 317.77 75.43 562.99 124.54 9927.40 7.18 0.06 2203.44 Bdl. Bdl. Bdl. Bdl. 29.93 Bdl. 43.92 14.04 224.15 62.10 363.95 63.69 606.81 96.15 9014.17 7.46 0.07 2350.94 8.06 Bdl. 5.65 13.32 22.15 Bdl. 60.19 9.90 345.57 49.71 372.96 90.05 644.50 134.51 12980.26 7.74 0.06 1903.82 Bdl. Bdl. 2.99 11.78 19.56 1.44 106.27 17.47 213.55 76.84 273.40 101.49 611.83 137.49 9925.62 8.01 0.07 2100.10 Bdl. Bdl. 2.29 Bdl. 22.45 Bdl. 54.90 22.56 192.63 96.67 326.65 102.92 737.58 93.26 11836.95 8.29 0.05 1782.00 5.64 Bdl. 1.59 18.77 20.72 Bdl. 67.53 8.67 169.66 36.37 239.30 48.37 500.70 94.32 8048.79 8.56 0.08 2439.04 Bdl. Bdl. 1.24 Bdl. Bdl. Bdl. 39.57 21.68 246.17 88.71 353.11 86.09 592.51 104.72 11684.16 8.84 0.07 1954.71 Bdl. Bdl. 2.16 Bdl. 14.11 Bdl. 57.49 30.72 173.34 59.52 295.73 82.37 456.96 77.76 9151.46 9.12 0.06 1853.89 9.40 Bdl. 0.99 11.82 12.99 Bdl. 84.67 6.52 121.57 62.13 405.50 84.25 475.53 84.02 9126.13 9.39 0.07 2160.95 2.60 Bdl. 1.10 Bdl. 7.21 Bdl. 29.36 21.72 379.47 83.19 351.34 61.71 521.01 110.52 10238.78 9.67 0.06 1844.71 Bdl. Bdl. 1.93 23.01 12.60 Bdl. 25.66 21.09 147.39 35.48 269.32 45.76 484.94 86.02 8861.46 9.95 0.07 1604.90 Bdl. Bdl. 4.10 12.24 Bdl. Bdl. 49.08 22.41 164.45 41.50 223.18 45.15 578.16 97.81 10821.66 10.22 365.10 2011.49 Bdl. Bdl. 3.05 12.15 Bdl. Bdl. 5.40 11.11 225.09 56.11 306.24 67.12 485.86 74.69 10163.38 10.50 0.07 1783.66 4.81 Bdl. 1.02 24.51 13.37 Bdl. 27.21 17.89 234.48 45.23 274.08 55.46 539.47 80.01 11564.77 10.77 327.68 1289.42 Bdl. Bdl. 0.90 Bdl. Bdl. Bdl. 23.99 19.72 144.72 44.89 176.19 36.68 337.40 73.37 8780.99 11.05 0.08 1399.58 2.54 Bdl. Bdl. Bdl. Bdl. Bdl. 34.53 11.83 214.94 65.85 235.47 53.16 471.11 77.85 10667.15 11.33 0.08 1914.97 Bdl. Bdl. 2.39 14.40 7.82 Bdl. 38.18 28.76 118.82 94.92 393.82 54.72 469.55 89.81 11480.21 11.60 0.08 1828.98 Bdl. Bdl. 1.11 Bdl. 14.47 Bdl. 23.55 14.52 169.14 44.96 308.75 69.38 590.63 69.25 10272.69    	 136	Table 20 LA-ICP-MS Depth Profiling Trace Element Concentrations for Zircon3 (SLCX 12) Depth                  (µm) Ti Y Nb La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf 0.00                  0.28 3.32 1773.53 3.82 Bdl. 1.02 Bdl. 6.95 Bdl. 24.23 12.08 150.32 49.08 260.09 53.15 483.48 91.80 8226.62 0.55 4.42 2423.98 9.59 Bdl. Bdl. Bdl. Bdl. Bdl. 22.49 14.68 218.13 83.93 364.50 120.32 872.92 142.38 12765.25 0.83 5.53 1155.41 2.12 Bdl. 1.12 Bdl. 3.84 Bdl. 8.94 6.08 65.66 53.05 185.68 63.55 527.80 87.91 6900.22 1.11 6.63 1618.64 3.16 Bdl. Bdl. Bdl. Bdl. Bdl. 4.43 12.64 149.61 75.08 275.90 50.73 693.54 136.11 11284.69 1.38 7.73 1677.43 6.23 Bdl. Bdl. Bdl. Bdl. Bdl. 21.76 8.88 115.13 59.05 307.44 49.88 776.34 87.01 10118.97 1.66 8.84 2089.23 Bdl. Bdl. 2.25 Bdl. 7.69 2.95 29.78 34.03 227.66 78.31 365.16 92.94 969.37 100.82 16899.11 1.93 9.95 1718.08 Bdl. Bdl. 3.09 Bdl. Bdl. Bdl. 28.62 11.68 78.14 64.16 318.63 74.20 808.34 120.83 11010.04 2.21 11.05 1773.19 9.38 Bdl. 2.45 Bdl. Bdl. Bdl. 21.66 14.14 178.28 90.01 270.02 92.39 908.50 201.40 14686.65 2.49 12.16 1961.49 2.92 Bdl. 3.81 50.02 Bdl. Bdl. 16.16 4.95 172.27 63.40 285.49 83.61 774.44 131.93 10670.98 2.76 13.26 1715.97 3.01 Bdl. 7.82 Bdl. 10.71 Bdl. 20.72 21.98 207.12 72.05 309.98 61.99 874.07 155.76 10573.15 3.04 14.37 1718.81 7.13 Bdl. 4.93 Bdl. 8.44 Bdl. 26.13 4.00 139.29 47.11 183.30 67.59 767.92 135.93 10108.72 3.32 15.47 1534.42 20.08 Bdl. 12.61 Bdl. Bdl. Bdl. 7.87 1.60 98.30 53.37 216.58 53.83 602.05 134.59 9650.62 3.59 16.58 1335.03 17.36 Bdl. 4.48 Bdl. Bdl. Bdl. 9.50 3.87 118.69 50.34 296.01 55.91 612.35 159.61 11405.27 3.87 17.68 1599.78 8.05 Bdl. 18.64 Bdl. 7.10 Bdl. 16.47 17.92 153.42 37.26 285.28 55.92 999.46 140.60 15159.34 4.14 18.79 1630.79 11.09 Bdl. 20.87 Bdl. 6.50 Bdl. 5.03 10.26 199.70 81.05 256.07 73.63 909.35 142.79 13585.84 4.42 19.89 3761.86 7.40 Bdl. 17.06 Bdl. Bdl. Bdl. 5.02 2.05 73.87 59.64 276.62 76.73 690.17 141.10 11176.23 4.70 21.00 1206.78 12.24 Bdl. 18.76 Bdl. Bdl. Bdl. 12.43 11.83 54.83 63.24 232.46 34.27 559.23 127.93 10994.25 4.97 22.10 1715.40 18.90 Bdl. 15.40 Bdl. 6.60 Bdl. 25.51 8.33 127.58 73.57 270.42 76.31 947.15 233.29 16732.40 5.25 23.21 1671.98 Bdl. Bdl. 9.29 Bdl. 5.79 4.42 17.92 10.96 98.82 66.48 256.00 84.09 772.02 193.78 10828.02 5.53 24.31 1166.04 30.31 Bdl. 25.60 Bdl. Bdl. Bdl. 18.09 16.61 119.78 53.71 258.55 90.68 839.68 166.40 10353.74 5.80 25.42 1337.60 11.96 Bdl. 15.88 12.40 Bdl. 1.98 16.03 11.44 147.39 62.88 245.73 73.96 758.41 151.19 11315.31 6.08 26.52 1625.23 39.87 Bdl. 27.41 14.98 Bdl. Bdl. 48.44 7.90 142.52 47.24 412.77 53.93 1103.44 169.30 12130.00 6.35 27.63 1560.93 7.75 Bdl. 19.48 Bdl. Bdl. 2.55 36.14 16.85 121.54 56.92 203.90 95.27 1126.45 215.68 12845.26 6.63 28.73 1390.56 15.75 Bdl. 25.29 Bdl. 10.84 Bdl. 8.38 8.54 67.80 42.63 248.17 83.96 929.12 245.09 12017.20 *All concentrations in ppm. Bdl. = below detecting limit. Data are as reported by the instrument. 	 137	Table 20 (Continued) Depth                  (µm) Ti Y Nb La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf 6.91 29.84 1826.64 8.24 Bdl. 37.11 Bdl. Bdl. Bdl. 5.46 6.69 184.92 71.81 227.14 102.55 1165.66 309.61 14230.35 7.18 30.94 1445.50 29.20 Bdl. 31.59 Bdl. 11.11 Bdl. 17.17 5.25 107.40 45.50 245.41 81.94 1174.69 214.09 10440.07 7.46 32.05 1542.56 15.09 Bdl. 43.22 Bdl. Bdl. Bdl. 14.94 12.19 146.57 73.89 258.79 112.47 1242.48 254.59 12542.60 7.74 33.15 1768.61 12.80 Bdl. 36.56 Bdl. 10.91 Bdl. 21.06 12.03 161.19 67.85 359.03 87.09 1081.45 259.83 11059.11 8.01 34.26 2303.67 15.46 Bdl. 57.45 15.69 Bdl. 1.25 20.30 8.28 156.85 53.77 374.50 100.07 1137.60 256.46 10293.21 8.29 35.36 2065.12 44.49 Bdl. 56.81 15.02 Bdl. Bdl. 34.00 17.83 193.01 86.46 398.81 84.95 1065.30 218.41 9867.13 8.56 36.47 2073.10 32.70 Bdl. 54.03 Bdl. 5.54 2.10 55.56 19.17 150.99 41.66 262.11 59.80 813.83 136.57 8706.78 8.84 37.57 1994.13 3.71 Bdl. 68.39 44.83 6.26 Bdl. 43.50 11.83 135.17 65.54 291.37 63.01 815.39 167.98 10742.98 9.12 38.68 2526.52 14.11 Bdl. 86.53 37.81 7.92 Bdl. 18.34 7.48 171.03 36.28 355.93 64.16 788.41 121.48 12301.78 9.39 39.78 1879.41 12.18 Bdl. 66.57 Bdl. 13.64 5.18 31.59 23.62 93.02 66.93 284.61 73.67 577.37 96.46 9904.91 9.67 40.89 1831.58 8.52 Bdl. 88.38 Bdl. 7.14 Bdl. 88.17 15.73 235.27 86.38 355.14 64.82 630.76 94.14 9911.63 9.95 41.99 1798.41 12.59 Bdl. 65.46 Bdl. Bdl. Bdl. 48.78 17.68 175.58 50.52 197.21 65.49 489.82 124.63 9041.75 10.22 43.10 1694.38 4.41 Bdl. 90.04 17.56 29.45 Bdl. 85.21 23.17 359.68 84.22 295.26 77.66 527.00 111.23 10617.19 10.50 44.20 1740.19 11.10 Bdl. 72.70 29.40 12.33 1.17 19.03 15.52 98.06 50.37 217.56 54.44 521.50 91.69 8435.67 10.77 45.31 2108.28 Bdl. Bdl. 104.68 54.13 15.14 4.31 75.91 9.52 206.38 64.30 406.72 79.82 640.18 121.68 10708.49 11.05 46.41 1591.27 8.93 Bdl. 74.39 Bdl. Bdl. Bdl. 51.42 4.66 143.04 58.07 243.53 67.20 605.73 115.54 9593.30 11.33 47.52 1640.41 Bdl. Bdl. 70.27 15.76 13.23 1.25 40.81 33.28 165.30 75.61 307.61 47.02 467.07 68.27 9165.10 11.60 48.62 2304.36 Bdl. Bdl. 109.07 Bdl. 17.04 1.61 52.54 18.75 241.85 86.21 211.67 81.41 775.41 124.73 11287.67 11.88 49.73 2536.55 25.86 Bdl. 53.30 Bdl. 17.04 Bdl. 39.42 21.43 241.91 66.75 273.19 66.81 672.65 104.34 8607.78 12.16 50.83 1606.57 4.63 Bdl. 56.49 Bdl. Bdl. 1.44 29.35 2.39 77.82 19.88 152.57 26.12 141.41 31.09 2390.13 12.43 51.94 1819.95 Bdl. Bdl. 61.33 Bdl. Bdl. Bdl. Bdl. 16.56 Bdl. Bdl. Bdl. Bdl. 48.93 Bdl. 311.15    	 138	Table 21 LA-ICP-MS Depth Profiling Trace Element Concentrations for Zircon4 (SLCX 12) Depth                  (µm) Ti Y Nb La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf 0.00                  0.28 0.23 3874.69 Bdl. Bdl. 22.14 13.50 19.16 3.18 46.75 9.47 479.34 113.51 558.65 112.01 1188.81 274.55 14429.24 0.55 100.16 2927.82 Bdl. Bdl. 23.12 26.11 12.35 1.02 63.28 25.62 313.53 114.73 423.68 102.73 1053.09 186.90 10900.49 0.83 0.25 2775.50 4.55 Bdl. 11.44 116.28 27.50 Bdl. 40.25 20.37 220.03 99.94 549.31 83.44 1042.46 200.04 10588.19 1.11 0.27 2862.03 2.52 Bdl. 33.84 48.38 15.26 5.05 22.33 6.78 185.19 114.98 534.62 131.98 987.62 179.61 13264.26 1.38 0.22 1828.62 2.02 Bdl. 23.82 51.89 12.28 6.10 17.96 18.18 338.59 61.10 277.41 63.41 784.29 134.52 10605.16 1.66 0.20 1627.82 7.55 Bdl. 26.21 193.77 22.92 6.64 20.96 8.48 170.67 75.53 375.44 81.06 595.90 181.03 9550.67 1.93 0.24 1894.11 Bdl. Bdl. 79.18 158.15 61.22 6.75 99.50 8.06 270.14 56.72 404.64 73.30 1008.09 174.05 13695.22 2.21 52.56 1943.05 6.29 Bdl. 49.49 229.14 31.89 11.60 60.63 13.22 189.94 60.03 360.08 58.69 683.86 144.01 11886.04 2.49 67.32 2439.29 5.35 Bdl. 66.58 223.81 73.31 6.73 35.74 14.47 215.63 56.95 306.53 111.50 846.60 138.83 11077.31 2.76 0.22 1815.82 8.23 Bdl. 22.62 53.10 18.84 1.04 64.29 3.72 117.77 57.42 288.32 66.23 544.76 120.03 11358.38 3.04 0.22 1585.81 6.15 Bdl. 11.27 52.92 Bdl. 2.07 22.88 1.85 110.46 45.44 188.39 39.31 573.55 96.53 10090.41 3.32 234.34 1713.56 Bdl. Bdl. 14.60 Bdl. 14.06 1.16 10.27 14.56 85.26 68.00 174.45 64.62 574.80 111.56 10273.26 3.59 67.05 1655.33 Bdl. Bdl. 8.89 16.95 Bdl. 1.32 29.31 18.99 106.15 88.39 295.60 70.14 655.93 136.50 12264.60 3.87 0.29 2006.59 Bdl. Bdl. 11.46 52.47 16.55 Bdl. 24.19 22.04 200.77 57.82 286.24 59.36 622.47 87.51 12827.19 4.14 0.30 1587.85 5.52 Bdl. 5.87 17.91 8.48 Bdl. 30.96 20.05 186.88 63.75 235.70 72.16 609.53 87.62 11478.04 4.42 0.31 1785.13 Bdl. Bdl. 12.11 36.97 8.75 2.89 12.78 2.59 154.28 63.43 295.79 39.19 636.08 114.50 11278.26 4.70 75.22 1750.63 5.78 Bdl. 9.85 56.41 Bdl. Bdl. 64.99 26.31 235.41 54.96 320.88 99.64 552.42 93.96 13244.94 4.97 0.34 1806.80 Bdl. Bdl. 2.68 20.44 Bdl. Bdl. 42.38 8.58 245.18 77.90 355.94 77.95 616.08 104.29 11833.05 5.25 0.36 1843.27 Bdl. Bdl. 4.17 42.49 10.05 3.31 36.70 26.74 132.96 64.77 354.81 78.76 656.68 156.79 12290.95 5.53 0.35 1616.77 Bdl. Bdl. 6.80 41.56 Bdl. Bdl. 64.61 8.72 162.55 47.51 295.28 48.41 489.64 96.93 10397.49 5.80 0.35 1677.72 Bdl. Bdl. 11.03 Bdl. Bdl. Bdl. 50.95 5.89 164.81 40.14 246.97 93.70 585.93 121.10 12753.13 6.08 89.94 1566.03 Bdl. Bdl. 2.90 Bdl. 20.97 Bdl. 38.27 3.10 115.55 64.72 251.81 60.98 513.39 62.45 11629.03 6.35 0.31 1389.52 2.85 Bdl. 3.67 37.40 8.85 Bdl. 32.29 13.07 165.73 42.73 258.89 69.25 411.43 68.88 7858.10 6.63 0.35 1464.73 Bdl. Bdl. 1.36 20.79 Bdl. 3.24 64.62 23.25 151.76 47.51 214.03 41.80 457.44 117.10 10328.88 *All concentrations in ppm. Bdl. = below detecting limit. Data are as reported by the instrument. 	 139	Table 21 (Continued) Depth                  (µm) Ti Y Nb La Ce Nd Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Hf 6.91 0.35 1415.65 Bdl. Bdl. Bdl. 21.07 Bdl. Bdl. 58.20 8.83 186.74 32.09 284.15 64.63 496.00 82.12 9345.79 7.18 0.29 1132.27 2.60 Bdl. 3.36 34.23 8.10 1.33 11.82 9.57 80.29 52.13 182.16 48.87 415.99 55.56 7701.48 7.46 0.36 1300.76 Bdl. Bdl. 2.84 65.20 20.57 Bdl. 30.01 6.07 101.95 33.09 215.83 62.03 528.11 75.22 9329.52 7.74 162.39 1164.12 2.98 Bdl. 2.57 19.66 9.30 1.53 47.48 30.20 153.64 22.44 306.65 45.70 477.47 87.12 9698.73 8.01 0.39 1751.48 10.72 Bdl. 7.71 47.19 Bdl. Bdl. 89.56 13.18 110.66 41.90 267.66 62.32 409.33 81.59 11163.58 8.29 88.97 1315.51 Bdl. Bdl. 1.40 Bdl. 20.26 Bdl. 36.94 32.89 156.19 67.88 189.71 54.28 478.67 74.01 10448.95 8.56 0.40 1402.03 Bdl. Bdl. 4.66 Bdl. 11.24 1.85 49.19 9.95 123.82 69.31 294.72 65.25 430.43 115.48 10896.78 8.84 0.41 1913.64 Bdl. Bdl. Bdl. Bdl. 69.43 Bdl. 33.74 13.65 114.67 31.00 285.89 82.62 433.42 142.54 10081.30 9.12 83.25 1098.50 Bdl. Bdl. 5.19 Bdl. 18.79 Bdl. 27.39 5.54 82.75 47.82 161.73 56.59 367.11 59.98 8608.88 9.39 0.35 1646.97 Bdl. Bdl. 2.73 20.90 Bdl. Bdl. 43.23 14.58 141.48 42.37 288.51 48.50 442.54 92.38 10886.65 9.67 0.37 1630.57 Bdl. Bdl. 5.76 66.16 Bdl. Bdl. 30.41 24.61 126.33 92.21 382.47 97.70 424.48 123.60 10611.56 9.95 0.34 1599.14 Bdl. Bdl. 2.65 Bdl. Bdl. Bdl. 13.99 11.32 137.40 51.42 301.64 40.67 679.66 96.21 12457.56 10.22 0.32 1334.24 Bdl. Bdl. 9.95 Bdl. 9.01 Bdl. 19.69 2.66 138.82 28.95 181.89 66.25 498.31 73.82 9299.71 10.50 0.34 1209.65 6.09 Bdl. 5.31 Bdl. Bdl. Bdl. 21.01 5.67 137.56 54.05 194.07 57.84 414.41 129.07 10653.82 10.77 0.39 1643.46 Bdl. Bdl. Bdl. 70.42 Bdl. Bdl. 56.59 13.08 183.24 50.51 315.29 71.71 604.74 136.34 11411.92 11.05 0.35 1663.91 6.36 Bdl. Bdl. Bdl. 30.15 Bdl. 29.27 11.84 187.99 80.69 240.30 55.95 457.49 70.82 9543.19 11.33 0.36 1729.81 Bdl. Bdl. 2.85 174.97 Bdl. Bdl. 37.65 18.28 159.31 71.96 270.43 52.96 563.20 138.67 10780.49 11.60 0.33 1416.24 2.82 Bdl. 1.23 Bdl. 8.92 Bdl. 45.48 5.26 108.02 52.54 200.00 41.72 522.23 60.82 9079.55 11.88 0.35 1719.37 5.72 Bdl. 3.76 38.39 Bdl. Bdl. 52.85 10.69 129.80 70.41 203.31 56.55 501.41 96.86 8235.31 12.16 0.36 1604.78 20.82 Bdl. Bdl. Bdl. Bdl. Bdl. 9.62 3.89 Bdl. 14.14 9.87 11.76 64.42 9.00 659.55  

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