University of Nevada, Reno a Study of Pleistocene Volcano Manantial

University of Nevada, Reno

A study of Pleistocene volcano Manantial Pelado, Chile: Unique access to a long history of primitive magmas in the thickened crust of the Southern Andes

A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Geology

Heather Winslow Dr. Philipp Ruprecht, Thesis Advisor May 2018

THE GRADUATE SCHOOL

We recommend that the thesis prepared under our supervision by

HEATHER WINSLOW

Entitled

A Study Of Pleistocene Volcano Manantial Pelado, Chile: Unique Access To A Long History Of Primitive Magmas In The Thickened Crust Of The Southern Andes

be accepted in partial fulfillment of the requirements for the degree of

MASTER OF SCIENCE

Philipp Ruprecht, Ph.D., Advisor

Wenrong Cao, Ph.D., Committee Member

Adam Csank, Ph.D., Graduate School Representative

David W. Zeh, Ph.D., Dean, Graduate School

May, 2018

ABSTRACT Textural and geochemical analysis of lavas and tephra from a poorly studied, glacially dissected, mafic, stratocone, Manantial Pelado, in the Southern Andean

Volcanic Zone was collected to characterize the volcano’s petrogenesis and assess its primitive nature. Manantial Pelado lies within the transitional segment of the Southern

Volcanic Zone (35.5°S) amidst thickened crust (~55 km) while surrounded by extensive silicic volcanism such as the Descabezado Grande-Cerro Azul Volcanic Complex. How mafic magmas reached the surface through thickened continental crust is a larger question at hand, but prior to addressing broader processes at work, initial geochemical characterization is necessary. Understanding the full extent of its primitive nature is crucial for broader insight of proximal vent interactions and relationships as well as insight towards magma genesis. A combination of the whole-rock and mineral-scale data reveals initial primitive characterization may not accurately represent the initial compositions and that their signature is truly primitive. Textural and zonation patterns of olivine, the presence of cr-spinel within olivine cores, and elevated Fo and Ni content within olivine cores provides evidence toward a more primitive signature for these lavas.

This led to further investigation of petrogenetic processes such as diffusive equilibration.

Mineral-melt relationships also provided magmatic reservoir constraints through the use of geothermometers and hygrometers to estimate crystallization temperatures, oxygen fugacity, and initial water content of these lavas. A potential variation in source of melting was identified as well as varying water contents.

ACKNOWLEDGEMENTS There are many people I would like to thank for their unending support through this entire process. Primarily, I am grateful for my advisor, Dr. Philipp Ruprecht, for the continual guidance and support through this project. This has been a massive learning experience and he never failed to challenge me as a scientist and writer while also acting as my biggest fan. I would also like to thank Ellyn Huggins and Max

Gavrilenko for their amazing help and constant patience as I tried to navigate through masses of data (and also hijacking our weekly meetings). A big thanks to Joel

Desormeau who provided an abundance of knowledge on analytical instruments as well as his support and encouragement. A special thanks to my committee members,

Dr. Wenrong Cao and Dr. Adam Csank, for their guidance and revisions, as well as my fellow graduate students (Scott Feehan, Michelle Dunn, Emma McConville,

Kelley Shaw, Sarah Trubovitz, Gabe Aliaga, Elizabeth Hollingsworth, and Curtis

Johson) for keeping me sane throughout the past two years. And finally, I would like to thank my parents and friends back home who have always been my biggest support system and motivators. I could not have done it without all of you!

iii

TABLE OF CONTENTS ABSTRACT…………………………………………………………………….………... i ACKNOWLEDGEMENTS……………………………………………………………... ii LIST OF TABLES………………………………………………………………………. v LIST OF FIGURES……………………………………………………………………... vi INTRODUCTION……………………………………………………………………….. 1 GEOLOGIC SETTING………………………………………………………………….. 7 Southern Volcanic Zone Geologic Setting……………………………………… 8 Geochemical Characterization of SVZ………………………………………….. 9 Silicic Activity near Manantial Pelado………………………………………… 10 Sample Location………………………………………………………………………... 11 Stratigraphic Description………………………………………………………………. 11 ANALYTICAL METHODS…………………………………………………………… 14 Whole-rock analyses…………………………………………………………… 14 Calculations for plotting……………………………………………………….. 14 Mineral Analyses………………………………………………………………. 14 Geochronology………………………………………………………………… 17 RESULTS……………………………………………………………………………… 17 Whole-rock data………………………………………………………………... 17 Petrographic Description………………………………………………………. 24 Mineralogical Data……………………………………………………………... 29 Order of Crystallization………………………………………………………... 29 DISCUSSION…………………………………………………………………………...33 Closed System Dynamics and Long-lived Storage…………………………….. 34 Source Variation………………………………………………………………... 41 Melt Composition Calculation…………………………………………………. 42 Oxygen Fugacity………………………………………………………………...45 iv

Hygrometers……………………………………………………………………. 48 MELTS…………………………………………………………………………. 55 CONCLUSION………………………………………………………………………… 56 REFERENCES…………………………………………………………………………. 60 APPENDIX……………………………………………………………………………...68

LIST OF TABLES

APPENDIX 68

Table A1. XRF+ICPMS Major and Trace Elements 69

Table A2. OSU EMP Olivine 73

Table A3. OSU EMP Pyroxene 77

Table A4. OSU EMP Plagioclase 79

Table A5. WUSTL EMP Olivine 83

Table A6. WUSTL EMP Oxide 91

Table A7. WUSTL EMP Spinel 97

A8. EarthChem References 101

LIST OF FIGURES INTRODUCTION

Figure 1A. Location map for Manantial Pelado study area 5

Figure 1B/C. Map of sample locations 6

GEOLOGIC SETTING

Figure 2. Field photos of the cinder cone, dike, and unconformable flow 12

Figure 3. Field photos of main lithologies 13

RESULTS

Figure 4. Subdivision of Subalkaline rocks 19

Figure 5. Major elements vs SiO2 20

Figure 6a. Spider diagram of Manantial Pelado lavas 21

Figure 6b. Extended REE diagram with Manantial Pelado and global data 22

Figure 6c. Regional extended REE diagram 23

Figure 7. BSE images of olivine textures 26

Figure 8. BSE image of olivine and transect diagram 27

Figure 9. BSE images of plagioclase textures 28

Figure 10. Trace elements vs SiO2 32

DISCUSSION

Figure 11. Fo (olivine) vs. Mg# (whole rock) 38

Figure 12. Fo (olivine) vs Ni (olivine) 39

Figure 13. MgO (wt%, WR) vs Ni (ppm, WR) 40

Figure 14. Oxygen Fugacity diagram 47

Figure 15. Ca-in-olivine hygrometer 54

CONCLUSION

Figure 16. Manantial Pelado magmatic reservoir schematic 59 1

INTRODUCTION Manantial Pelado is a Pleistocene stratocone in the Southern Volcanic Zone

(SVZ) of the Andes (Fig. 1A) and resides among extensive, regional, silicic volcanism as a result of thickened crust. The SVZ is littered with active volcanic centers ranging from smaller monogenetic cones, large stratocones, and large caldera forming eruptions (Stern,

2004). Large volumes of high-silica rhyolites have erupted from Pleistocene to recent years from caldera-forming systems such as Laguna del Maule (Anderson et al. 2017),

Puyehue-Cordon Caulle (Singer et al. 2008), Maipo (Stern et al. 1984a), and Calabozos

(Hildreth et al. 1984; Grunder, 1987). Proximal to Manantial Pelado (15 km S), sits the

Descabezado-Cerro Azul Volcanic Complex (Fig. 1A). Volcán Quizapú lies on the northern flank of Cerro Azul and has had the two largest historical eruptions both emitting >9.5 km3 (Hildreth & Drake, 1992; Ruprecht et al. 2012).

The SVZ is highly active and with extensive valleys and rivers providing channelized pathways for deposits to reach the largest city in Chile, Santiago, ~100 km away, it poses significant natural hazards (Stern, 2004). Mafic and more primitive magmas are the building blocks to highly evolved systems such as the vents densely populating the SVZ (Sigurdsson et al. 2015). Mafic magmas contribute heat and mass to sustain the presence of a long-lived shallow magma systems as well as volatile elements such as H2O, CO2, and SO2 to an emerging gas phase. As a result, the mafic input modulates magma compositions in the volcano’s subsurface, alter the eruptibility and the eruptive behavior of stored magmas, and affects the frequency of eruption. Therefore, it is vital to characterize the mafic magma input into the crust and its evolution as it 2 interacts with magmas already stored in the crust, ultimately aiding the forecasting of volcanic unrest and activity. In areas of highly evolved volcanism, a chance to look back into its history and origin of magma genesis could provide substantial insight into how the system has evolved temporally, what to expect in other locations with similar compositions, and insight on magmas that have fed the upper crustal system.

Volcán Manantial Pelado, is a poorly-studied basaltic andesite to andesite stratocone within the transitional segment of the Southern Andean Volcanic Zone (SVZ,

33-37° S). It is one of the few mafic to intermediate centers in an area otherwise surrounded by voluminous silicic magmatism. The most recent regional silicic activity, including historic eruptions at Quizapú (Hildreth & Drake, 1992; Ruprecht et al. 2012), occurs within the Descabezado Grande-Cerro Azul (DG-CA) Volcanic Cluster (Fig. 1A), but many other silicic centers exist within about a 50 km radius. Especially high-silica rhyolite eruptions in Holocene and Pleistocene times have been studied East and

Southeast of Manantial Pelado. The Calabozos Caldera produced at least three large caldera-forming eruptions (each >100 km3) of high-silica rhyolite (Hildreth et al. 1984;

Grunder, 1987). The Laguna del Maule system to the Southeast is among the most productive regions of high-silica rhyolite in the Holocene (Anderson et al. 2017) and currently is experiencing one of the world’s fastest inflation episodes, likely related to magmatic activity (Le Mével et al. 2015). Smaller silicic centers are distributed throughout the area.

The MASH hypothesis, a major modern paradigm in continental arc petrogenesis, was developed in this part of the Andes (Hildreth &Moorbath, 1988). It postulates the 3 presence of a deep-seated region of magma differentiation near the crust-mantle boundary, where mixing, assimilation, storage, and homogenization (MASH) interfere with primitive mantle derived magmas ascending from the mantle wedge into the crust.

As a result, the mantle melt signature is obscured and more evolved magmas ascend into upper crustal levels, which leads to the extensive amount of silicic volcanism in this area.

These silicic magmas act as density filter that further inhibits primitive magmas from reaching the surface. Thus, constraining the magma input into the crust from primitive basalts has been challenging in this region of the Andes.

The extensive amount of silicic volcanism in this area supports the MASH hypothesis (Mixing, Assimilation, Storage, Homogenization) (Hildreth &Moorbath,

1988) which suggests a MASH zone lies at the crust-mantle boundary and interferes with any primitive or parental magmas ascending from the mantle wedge. This inhibits primitive magmas from reaching the surface and as a result, primitive basalts have yet to be found in this region of the Andes (hildreth & Moorbath, 1988). Manantial Pelado may represent a rare location in this region to explore the characteristics of primitive arc magmas as its eruptive products are dominated by mafic lavas.

While mafic centers play a major role in understanding the regional magma genesis, only few studies have focuses on the primitive magmatism in this region of the

Andes. At Tatara-San Pedro Volcanic Complex (e.g. Dungan et al. 2001) extensive work provided some constraints on the mafic input. More recently, a tephra study was conducted on a selection of small cinder cones (Jacques et al. 2013). However, many of those are too evolved to constrain primitive magmas, further corroborating the presence 4 of a MASH region. Similarly, on the basis of a regional study using whole rock geochemistry Hildreth et al. (2010) found few centers truly erupting primitive magmas in this region. Alternatively, some constraints have been deduced from mafic enclaves in otherwise silicic eruptions (Ruprecht et al. 2012). Thus, the region’s primitive magmas remain elusive and any additional study shedding light on this is essential.

Here, I am using the mafic center, Manantial Pelado, as a case study to shed light on the area’s primitive history and to address how the mafic system influences modern magmatism by studying the compositional diversity of the mafic magmas. It is critical to establish a baseline parental composition of this system to fully understand the center’s evolution, internal plumbing system, and potential contribution to nearby centers. Since

Manantial Pelado is a stratocone, I will also explore how near primitive magmas can reach the surface and minimize the effect of a pervasive MASH region despite prolonged focused activity. In particular, this study focuses on the magmatic characterization of

Manantial Pelado using geochemistry and petrographic analysis to understand its evolution and magmatic diversity. Not only are results from Manantial Pelado important for our understanding of the internal architecture of the crust, but this study also provides new constraints for the silicic systems in the region, such as DG-CA, where only limited knowledge exists about the magmas feeding and driving the upper crustal magma systems. Lastly, Manantial Pelado is an ideal field site due to its accessibility within the

Andes, lack or previous study, and close proximity to nearby volcanic systems (Fig. 1A).

Its glacially dissected valleys also provide access to its long history of mafic magmatism

(Fig. 1B). 5

stratigraphic context.

uption. B) uption. B) locationsSample up Viewthe valley. to areawestern North. showingC) Field progression of lava Figure Figure 1. MapA) view of Manantial Pelado field site as as well surrounding silicic (black) mafic and centers. volcanic (red) JFR stands for Juan Fernandez Ridge and MFZ represents the Mocha Fracture Zone.The white pumice is from cover the er Quizapu 1932 fromflows Pelado. Manantial Its glacially dissected edifice access provides to a long temporal record. Samples were collected up eroded valleys for 6

Figure 1B. View to the North of dissected valley where strategic sampling occurred up the Western Valley.

Figure 1C. View to the East of the sampled Western Valley. Several lithologies were identified: black (basaltic andesite), blue (aphyric andesite), red (plagioclase andesite), green (scoria), yellow (Cerro Redondo Cinder Cone). 7

GEOLOGIC SETTING Andean magmatism is highly variable along-strike in its geochemistry and the regional tectonic control. At large, the Andes are the result of NE-trending (~080° azimuth) oblique subduction of the Nazca plate beneath the South American plate at a rate of ~7-9 cm/yr (Stern, 2004). Such a fast convergence rate results in strong compression leading to crustal shortening and thickening. The Andes range in crustal thickness from ~40-45 km in the Northern Volcanic Zone (NVZ), >70 km throughout the

Central Volcanic Zone (CVZ), thins from ~60-30 km throughout the Southern Volcanic

Zone (SVZ) and into the Austral Volcanic Zone (AVZ) (Stern, 2004). Changes in continental crust thickness are supported through various geochemical proxies. Most notable, multiple studies have shown a southward drop of K2O at a given SiO2 values and systematically lower δ18O, and 87Sr/86Sr ratios towards the South correlated with increasing MgO and 143Nd/144Nd ratios from N-S (Grunder, 1987; Stern and Kilian;

Hildreth and Moorbath, 1988; Rodriguez et al. 2007). Moreover, a gravity survey further supports the change in crustal thickness (Tassara et al. 2006).

Andean morphology varies from a maximum width of ~400 km at 18.5°S in the

Altiplano-Puna Volcanic Complex to less than 200 km width both north and south of the plateau due to a decrease in crustal shortening (Tassara et al. 2012; Ramos et al. 1996).

The geometry of the subducting slab changes throughout the arc creating four segments of volcanism: Northern, Central, Southern, and Austral Volcanic Zones. Each zone is separated by a gap in volcanic activity attributed to the subduction of aseismic ridges causing shallow angle/flat-slab subduction. Aseismic ridges are thickened oceanic ridges typically formed from ancient hot spots that are too buoyant to subduct steeply (>30°) 8 underneath the overlying slab. This results in the removal of the mantle wedge and halts volcanism.

Southern Volcanic Zone Geologic Setting The continental crust progressively thins southward from ~60 km at 33° S to ~30 km at 46° S (Hildreth and Moorbath, 1988). The crustal thickness in the Manantial

Pelado area is ~55 km estimated from a lithospheric structure model with the use of elastic thickness, seismic, and gravity data (Tassara et al. 2006). This gradational crustal thinning to the South together with an equidistant volcanic arc from the trench for the entire SVZ suggests a constant geometry of the lower plate and this simple geometry was utilized by Hildreth and Moorbath (1988) to study in isolation how continental crust thickness and structures of the upper plate influence volcanism. From this study it was found the SVZ acts as a great case study for the MASH hypothesis (Mixing,

Assimilation, Storage, and Homogenization). MASH is a hypothesized zone that lies within the lower crust-mantle boundary and influences the trajectory of parental basaltic magmas ascending from the mantle wedge. Magmas become neutrally buoyant at this boundary and experience mixing, assimilation, and induce partial melting. (Hildreth &

Moorbath, 1988). Simple continental crust contamination does not represent MASH processes, but is the actual generation of new magma (Hildreth & Moorbath, 1988).

The SVZ terminates to the north at 33° S with the subduction of the Juan-

Fernandez Ridge (JFR) and terminates to the south with the subduction of an active spreading center (Chile Rise Triple Junction) at 46° S. The SVZ displays across-arc variations as well as with E-W offsets of volcanic segments. Exact location of volcanic segments has been argued and has multiple grouping schemes (Tassara et al. 2012; Salas 9 et al. 2017; Lopez Escobar et al. 1995; Dungan et al. 2001). Essentially, all are based on chemistry and lateral offset and result in four zones: the Northern (NSVZ), the transitional (TSVZ), the central (CSVZ), and the southern (SSVZ). A major eastward lateral shift in segments occurs at 36° S as well as a dramatic increase in crustal thickness where the Mocha Fracture Zone projects underneath Nevado de Longaví separating the

TSVZ from the CSVZ (Fig. 1A) (Lopez Escobar et al. 1995). Thus, Manantial Pelado is part of the transitional segment and experiences drastic crustal thickness changes.

Geochemical Characterization of SVZ The geochemical changes along-arc evolve northward. The NSVZ is dominated by andesitic compositions and does not contain any mafic magmas. These lavas are characterized by high abundances of incompatible elements and Sr isotopic ratios

(Hildreth and Moorbath, 1988; Ruiz et al. 2001). Volcanic rocks from the TSVZ and

CSVZ are comprised of both andesitic and basaltic andesites with the abundance of basalts increasing southward. Continental crustal contributions are still observed at these latitudes (Grunder, 1987; Jacques et al. 2013). The SSVZ is dominated by mafic lavas with very minimal crustal contribution.

Manantial Pelado lies within the TSVZ where extensive primitive volcanism is scarce. Aside from Manantial Pelado, there are several other mafic-intermediate centers in that area: La Resolana, Cerro Rajaduras, Cerro Colorado, and Los Hornitos; the latter containing the most primitive magmas in the SVZ (Fig. 1A; Salas et al. 2017). Based on surface exposure La Resolana and Los Hornitos are short-lived (potentially monogenetic) cinder cones, as for which some geochemistry has been reported (Ruprecht et al. 2012;

Salas et al. 2017). The presumably longer-lived system (Cerro Rajaduras and Cerro 10

Colorado) that have an extensive eruptive history, like Manantial Pelado, have yet to be studied in detail. Thus, it remains unclear how the primitive and mafic magmas are preserved after ascending through thick and silicic continental crust, especially in the context of prolonged magmatic activity of a single magma system. A possible mechanism that provide pathways for magma transport through thickened crust could be controlled by regional fault systems, which limit the time of crustal storage for magmas to differentiate. A major and active fault zone is the N-S striking, dextral Liquiñe-Ofqui

Fault Zone (LOFZ) (Fig. 1A; Salas et al. 2016), which could potentially provide modern and rapid ascent pathways for mafic magmas to reach the surface (Cembrano and Lara,

2009). Although it is an arc-wide feature extending over >1000 km along the SVZ, its trace vanishes South of Manantial Pelado. Nonetheless, smaller regional faults associated with the LOFZ may extend into the field area (Salas et al. 2016).

Silicic Activity near Manantial Pelado Located approximately 10 km to the SE of Manantial Pelado is the most recent regional silicic activity which occurs within the Descabezado Grande-Cerro Azul (DG-

CA) Volcanic Cluster (Fig. 1A). The DG-CA consists predominantly of stratocones active throughout the Pleistocene and Holocene. Volcán Descabezado Grande and Cerro

Azul are adjacent stratocones whose compositions range from andesite to rhyodacite. A constructive flank cone, Quizapú, residing on the northern flank of Cerro Azul, represents the most recent volcanic activity manifested by intermediate to silicic eruptions in 1846-

47 and 1932 (Ruprecht et al. 2012). The DG-CA Volcanic Cluster is underlain by a 7 Ma granodiorite pluton and ~0.3-1.1 Ma andesitic lavas. 11

Sample Collection This study focuses on the western and southern sectors of the volcanic edifice where the glacial valleys provide excellent access and stratigraphic continuity to large parts of the volcanic activity and history of Manantial Pelado. A total of 53 samples were collected throughout the stratigraphic sections mainly comprised of lava flows with several tephra deposits from an adjacent cone, a prominent dike, and a lava flow that is truncated by an unconformity (MP-17-26, MP-17-29, and MP-17-25 respectively) (Fig.

1C, Fig. 2). Three lithologies were identified: olivine-plagioclase porphyritic basaltic andesite, nearly aphyric andesite, and plagioclase andesite (Fig. 3).

Stratigraphic Description The basal flows as they are exposed in the studied valleys are exclusively Olv-plg porphyritic basaltic andesite. The aphyric and plagioclase-andesite occur later in

Manantial Pelado’s history, yet are intermittently deposited between the basaltic andesite lavas creating drastic changes of composition within close proximity spatially (Fig. 1C).

Aphyric andesite is always found directly overlying basaltic andesite lavas as a single flow (Fig. 2), and the plagioclase andesite lava is typically found up sequence to the aphyric andesite (Fig. 1C). The basaltic andesite lavas gradually decrease in clinopyroxene as they evolve upward to the overlying aphyric andesite based on hand sample observations from MP-17-01, 04, 09, 08 (aphyric). MP17-09 is the final basaltic andesite flow prior to the aphyric andesite (MP-17-08). 12

Figure 2. A) Cinder cone, Cerro Redondo, surrounded by extensive basaltic andesite lava flows. View to the NW. B) Prominent dike cutting through volcanic neck. View to the S. C) Basaltic andesite (MP-17-25) truncated by unconformity. View to the SE. 13

Figure 3. A) Olivine-plagioclase porphyritic basaltic andesite outcrop and hand sample. (MP-17-33). B) Aphyric andesite outcrop and hand sample (MP- 17-08) directly overlying porphyritic basaltic andesite (MP-17-09). 14

ANALYTICAL METHODS Whole-rock analyses X-ray fluorescence (XRF) analyses of 19 whole-rock samples were carried out at the GeoAnalytical Lab at Washington State University following the analytical procedure of Johnson et al. (1999) (Appendix A1, Table 1, Table 2). For major element analysis, rock powders mixed with di-lithium tetraborate flux (2:1 flux:rock) were fused to glass beads at 1000°C in a muffle oven and refused again to produce a flat analysis surface.

Inductively coupled plasma mass spectrometry (ICP-MS) analyses were carried out using their high-resolution single collector Finnigan Element2 ICP-MS.

Calculations for plotting Throughout the work, several calculations will be referenced such as: Mg# or

Fo=(Mg/(Mg+Fe*))*100, An content= Ca/(Ca+Na+K),and Cr#=Cr/(Cr+Al) where atomic% is used for those calculations. FeO* is calculating total Fe all as ferrous.

Mineral Analyses Mineral chemistry was determined via electron microprobe at Oregon State

University and Washington University in St. Louis (WUSTL). At Oregon State

University measurements were performed on a Cameca SX-100 equipped with five wavelength dispersive spectrometers (WDS) and one energy dispersive spectrometer

(EDS). For Oregon State University data, a total of seven samples from Manantial Pelado were analyzed, six were basaltic andesites to examine temporal evolutionary changes

(two of which were the dike (MP-17-29) and an unconformable flow (MP-17-25)), and one sample was an aphyric andesite (MP-17-08). The results of analyzed olivine, pyroxene, and plagioclase phases from Oregon State University are reported in Appendix 15

A1 (Table A2, A3, A4 respectively) with 2-point core-rim analyses to estimate zonation followed by oxide results with 1-point per grain measurements.

Phases analyzed at Oregon State University were conducted at 15 kV accelerating voltage and a focused beam (1 µm) with the exception of plagioclase where a 5 µm beam diameter was used. Olivines were analyzed at 40 nA beam current and calibrated to the olivine FO83 standard. Si, Al, Mn, Fe, Ni, Na, Mg, Cr, Ti, and Ca analyzed. Using the

FO83 check standard, major elements are within <3% (2σ) reproducibility. Pyroxenes were analyzed at 30 nA beam current and calibrated to the augite KAUG standard. Si, Al,

K, Fe, Na, Mg, Ti, Ca, Mn, and Cr analyzed. Using the KAUG check standard, major elements are within <3% (2σ) reproducibility. Plagioclases were analyzed at 30 nA beam current and calibrated to the plagioclase LABR standard. Na, Mg, Si, Al, Fe, Ca, K, and

Sr analyzed. Using the LABR check standard, major elements are within <3% (2σ) reproducibility. Oxides were analyzed at 50 nA beam current and calibrated to the chromite CROM standard. Si, Al, Fe, Mn, Mg, Ca, Ti, Cr, Ni, V, and O were analyzed.

Using the chromite CROM check standard, major elements are within <3% (2σ) reproducibility.

Trace element high-precision analysis was collected at Washington University in

St. Louis using a JEOL JXA-8200 electron microprobe equipped with 5 WDS and a SDD

EDS detector. A total of 8 samples were analyzed – all of which were basaltic andesites.

High-precision data was necessary for analyzing trace elements in olivine as well as for using geothermobarometer methods for the oxides. 2-point core-rim analyses was performed on olivine as well as traverse paths, and 1-point analyses were performed on oxides as well as collecting ilmenite-magnetite oxide pairs. The results of analyzed 16 olivine, groundmass oxides, and spinel phases from WUSTL are reported in Appendix

A1 (Table A5, A6, and A7 respectively).

Olivine and oxides were analyzed with 3 µm beam diameter, 15 kV accelerating voltage, and 150 nA probe current. The following elements were analyzed and their peak counting times follows: Na (45 s), Mg (45 s), Al (90 s), Si (20 s), Ti (70 s), V (30 s), Fe

(30 s), P (60 s), Ca (45 s), Cr (45 s), Mn (30 s), and Ni (30 s). Standards for analysis are in the respective order: Albite Amelia P-103 (S1-1), Forsterite Shankland syn P-658 (S1-

6), Anorthite, Alaska (S1-2) NMNH 137041, Wollastonite Gates (S1-12), TiO2 GRR (S1-

21), Vanadium Taylor 22, Fe2O3 Elba Hematite P-238 (S1-25), Apatite (Fluor) Durango,

(S1-32) NMNH 104021, Wollastonite Gates (S1-12), Cr2O3 P-585 (S1-22), Mn Olivine

RDS P-1087 (S1-8), Ni Olivine syn P-877 (S1-9).

Plagioclase was analyzed using a beam of 20 µm diameter, at 15 kV, and 25 nA probe current. Na (30 s), Mg (200 s), Al (100 s), Si (30 s), Ba (180 s), Ti (30 s), Fe (45 s),

Cl (30 s), K (30 s), Ca (50 s), Sr (90 s), P (140 s), and S (30 s) were analyzed using the following standards in respective order: Albite Amelia P-103 (S1-1), Forsterite

Shankland syn P-658 (S1-6), Spinel MgAl2O4 Taylor 7, Wollastonite Gates (S1-12),

Barite Taylor 46, TiO2 GRR (S1-21), Mn Olivine RDS P-1087 (S1-8), Fe2O3 Elba

Hematite P-238 (S1-25), Tugtupite Na4BeAlSi4O12Cl (S2-34), Orthoclase, Madagascar

GRR78 (S2-1), Wollastonite Gates (S1-12), SrTiO3 Taylor 36, Apatite (Fluor) Durango,

(S1-32) NMNH 104021, Anhydrite Taylor 18. Background corrections for plagioclase were done using the Mean Atomic Number (MAN) methods from Donovan et al. (2016). 17

Geochronology Age dating of eight samples using the Ar40/Ar39 method was carried out at USGS

Menlo Park in order to provide the first constraints on the longevity of magmatism at

Manantial Pelado. Samples cover the entire stratigraphy in the studied valleys.

Groundmass samples were crushed at the University of Nevada, Reno. Final sample preparation including hand-picking, washing, acid rinse, and irradiation was performed by USGS staff members. Results will be available in mid-late May (2018).

RESULTS Whole-rock data Bulk rock compositions of lavas are clustered in SiO2 content ranging from 52-64 wt% SiO2 (Table A1; Fig. 4). Basaltic andesite lavas are restricted to 52-54 wt% SiO2 separating them from the andesitic lavas which sit at 61-64 wt% SiO2. Bulk compositions also range from 1-7.5 wt% MgO with a gap in data from 2-4 wt% MgO and 41-54 in

Mg# (Fig. 5). Basaltic andesite samples are restricted to 5-7.5 wt% MgO (55-70 Mg#),

30-85 ppm Ni (Fig. 10) and show minimal compositional evolution stratigraphically while deposited over the entire eruptive history of the volcano.

Trace element analyses for Manantial Pelado basaltic andesites (Table A2) display typical subduction zone characteristics (Fig. 6a) with enrichment in large ion lithophile elements (LILE), Rb, Ba, Th, U, Pb, Sr, K, depletion in Ti, Y, and the typical

Ta-Nb trough. The more evolved lavas show similar subduction zone trends, but in general are more enriched with the exception of elements affected by crystal fractionation. Sr is depleted relative to other trace elements and Eu displays a negative anomaly both supporting the fractionation of plagioclase. One sample of the aphyric 18 andesite displays P depletion potentially indicating apatite fractionation. Manantial

Pelado plots near other regional primitive centers in the SVZ, especially Los Hornitos which is the most primitive center in this area (Fig. 6c). Los Hornitos and Manantial

Pelado are almost identical in the REE diagram which displays the primitive extent of

Manantial Pelado.

Figure 4. Subdivision of subalkaline rocks. Samples display primarily calc-alkaline characteristics. Olivine-bearing basaltic andesite plots near tholeiitic compositions. Grey data points are regional whole rock compositions taken from USGS, GEOROC, and PETDB of nearby and surrounding centers (See Table A8 in the Appendix for references). Black is basaltic andesite, blue is aphyric andesite, red is plagioclase andesite, green is scoria. 20

Figure 5. Major element vs SiO2 diagrams compiled. Black: basaltic andesite, Blue: aphyric andesite, Red: plagioclase andesite, Green: scoria. Triangle: Unconformable unit (25); Diamond: dike (29); Square: cinder cone. Fx represents fractional crystallization.

Figure 6a. Spider diagram of Manantial Pelado data distinguishing differences in lithologies. Black is basaltic andesite (dominant lithology), blue is aphyric andesite, red is plagioclase andesite, green is scoria composition. INSET: Black is basaltic andesite of MP, dashed lines are regional tholeiites, and dotted lines are regional calk-alkaline basalts (CAB) (Grey dashed = CAS TH BAS (Cascade Tholeiite Basalt), dark grey dashed = Puyehue, purple dashed = VAN BAS, red dotted = SVZ CAB, dark red dotted = MEX CAB, Orange dotted =CAS CAB) (Schmidt & Jagoutz, 2017). 22

Figure 6b. Extended REE diagram. Manantial Pelado basaltic andesite samples are in black, red and orange are other typical calc-alkaline basalt (CAB) compositions from Mexico and the Cascades whereas the blue and light blue are other typical tholeiitic basalt compositions (Tho Bas) from the SVZ and the Cascades (Schmidt & Jagoutz, 2017). 23

Figure 6c. Regional extended REE diagram. Manantial Pelado basaltic andesite samples are in black. This diagram displays how Manantial Pelado compares to other volcanic centers in the SVZ (Schmidt & Jagoutz, 2017; Wehrmann et al. 2014). 24

Petrographic Description Manantial Pelado lava flows are made up of three main lithologies: olivine- plagioclase (olv-plg) porphyritic basaltic andesite, nearly aphyric andesite, and plagioclase-porphyritic andesite (Fig. 3). Olv-plg porphyritic basaltic andesite are by far the most common rock in Manantial Pelado’s eruptive history. These volumetrically extensive lavas are 5-10 m thick, extend more than 4.5 km from the main edifice, and are moderately vesiculated. The phase assemblage, in order of abundance, consists of phenocrysts of calcic-plagioclase, olivine, clinopyroxene, and microcrysts and microlites of orthopyroxene and sodic-plagioclase in the groundmass, respectively. Plagioclase phenocrysts are euhedral (occasionally subhedral) and range from 1-2 mm in size.

Plagioclase zoning patterns and textures are variable. Some grains contain prominent sieved cores and/or growth zones with abundant melt inclusions, while zoning can range from predominantly normal zonation to occasional reverse zonation (Fig. 9). Olivine is the most abundant mafic phase with large phenocrysts (2-3 mm) and subhedral to euhedral shape. It is characteristic of these lavas in hand samples. Olivine shows weak normal zonation near the rims, and is frequently overgrown by orthopyroxene rims (<0.2

µm wide) (Fig. 7, 8). Spinel inclusions are present within olivine cores. Clinopyroxene is the least abundant phenocryst phase (1-3 mm) and if present commonly forms glomerocrysts with olivine (Fig. 7). The holocrystalline groundmass (crystals <150 µm) consists of plagioclase, orthopyroxene, pigeonite, and Fe-Ti oxides with slight trachytic textures around large phenocrysts. Titanomagnetites are the dominant Fe-Ti oxide and ilmenites are rare. 25

The nearly aphyric andesite contains minor plagioclase phenocrysts (~10%) that are commonly acicular crystals (1-6 mm). Olivine is rare (<<1%), but when present occurs in clusters of anhedral crystals. Apatite occurs as an accessory phase. These lavas are consistently found as individual flows directly overlaying the basaltic andesite lavas with the depositional contact exposed. The third lithology, plg-porphyritic andesite, contains plagioclase (<1 mm), no mafic phenocrysts, and is commonly found above the aphyric andesite with no contact exposed.

Figure 7. BSE images typical olivine textures from basaltic andesite lavas (MP-17-01, 04, 33, 36). Images display glomerocryst textures, spinel inclusions, opx overgrowth, olivine zoning, and cpx-plag interactions.

Figure 8. A BSE image of an olivine from MP-17-04 on the left. The green box represents the transect location. The graph on the right displays the transect as it progresses from the core to rim. This progression displays the extent of the weak normal zoning within the basaltic andesites.

Figure 9. BSE images of typical plagioclase textures from basaltic andesite lavas (MP-17-01, 04, 09, 33). Images display normal and reverse zoning as well as sieved textures. 29

Mineralogical Data Olivine was analyzed for the eight basaltic andesite samples (254 analyses (73

OSU, 181 WUSTL)) with core compositions ranging from Fo~67-87.6 while rim compositions range from Fo~62-79. Most olivine core compositions scatter around Fo80-

84. There is a wide range in Ni content within the cores from ~300-2100 ppm (Fig. 10).

The spinel inclusions present in olivine cores are commonly Cr-spinels with the majority of them having a Cr# of 0.5. The overall range is from 0.3-0.7 (58 high precision analyses). The presence of Cr-spinels suggests these lavas are primitive (Clynne & Borg,

1997). Pyroxene was analyzed for the six basaltic andesite samples (39 analyses) with clinopyroxene phenocrysts (Mg#~68-83) and occasional orthopyroxene and pigeonite within the groundmass.

Plagioclase was analyzed for all samples (234 analyses (143 OSU, 91 WUSTL)) displaying anorthitic cores (An~75-89) with more sodic rims and microlites in the groundmass (An~46). The aphyric andesite contained <10% phenocrysts with plagioclase cores of An~43-54 overlapping with the rim compositions of the more primitive samples.

Thus, these more evolved lavas are similar to the groundmass of the basaltic andesite.

Order of Crystallization All samples from Manantial Pelado follow a trend of fractional crystallization.

The majority of Manantial Pelado lavas are more mafic and therefore observing their trends plotted against MgO can provide more details into their primitive nature. The basaltic andesites display a trend consistent with olivine fractionation (Fig. 5, 10). Ni immediately and consistently depletes until ~ 4 wt% MgO showing initial olivine fractionation along with immediate depletion of Mg# vs SiO2 (Fig. 5, 10). At 2 wt%

MgO, Ni flattens out while MgO continues to deplete (Fig. 10). This suggests other 30 phases that affect MgO but not Ni could start to crystallize. Olivine and Cr-spinel crystallization control MgO, Ni, and Cr behavior, but MgO can be affected by other phases such as pyroxene. While MgO and Ni whole-rock data display evolutionary trends, Cr is not analyzed to the needed precision except for in mineral-scale analyses.

FeO* is enriched until ~ 4-5 wt% MgO followed by depletion due to Fe-oxide crystallization (Fig. 5). TiO2 is enriched until 4 wt% MgO, and begins to deplete at 2 wt% MgO. Initial enrichment within the basaltic andesite suggests Ti-oxide suppression until 2 wt% MgO where ilmenite starts to crystallize (Fig. 5). At ~ 5 wt% MgO, CaO and

Sc contents drastically decrease indicating clinopyroxene crystallization that could co- crystallize with plagioclase (Fig. 5, 10; Gavrilenko et al. 2016). The fact that plagioclase and pyroxene potentially join the liquidus is supportd by Al2O3 and Sr, which show initial enrichment followed by depletion also at ~ 5 wt% MgO (Fig. 5, 10).

Plagioclase is the most common mineral phase, however, there is no evidence that it fractionated significantly from the erupted lavas. The basaltic andesites show no Eu anomaly (Eu/Eu* ~ 1) (Fig. 6a). Sr and Al2O3 trends also lack evidence for significant fractionation (Fig. 5, 10). Because Al2O3 is initially enriched whereas CaO shows a flat trend (from 5-8 wt% MgO) clinopyroxene crystallizes prior to plagioclase crystallization; however, textural patterns of large euhedral plagioclase and high phenocryst abundance of plagioclase suggest plagioclase is crystallizing either prior or synchronously as clinopyroxene.

The most evolved sample from the aphyric andesite is the only unit to display strong depletion in P which suggests apatite fractionation (Fig. 6a). The plagioclase and 31 aphyric andesite samples display a Sr depletion as well as a negative Eu anomaly indicating plagioclase fractionation.

Figure 10. Trace element vs SiO2 diagrams. Key is the same as in Fig. 5.

DISCUSSION This study capitalizes on the use of whole-rock and mineral data to provide a further look into crystal-melt relationships. Using a combination of methods, magma reservoir constraints can be estimated and processes of petrogenesis can be revealed.

Typically, to understand crystal-melt relationships, melt data is required (which is unavailable in the Manantial Pelado dataset at this time), however, whole-rock data can be used as a proxy for melt data in systems where minimal fractionation has occurred.

Smooth trace element patterns (Fig. 6) suggest minimal fractionation which allows whole-rock data to be used in place of melt compositions. The amount of fractionation can be quantified through a mass balance calculation using Ni data from Manantial

Pelado (Fig. 10) and characteristic concentrations for primitive compositions (Schmidt &

Jagoutz, 2017).

Mass Balance Calculation:

Nipm = NiWR f + Nipr. olv (1-f), where NiWR is the measured maximum Ni content in the whole rock of Manantial Pelado lavas (85 ppm, Fig. 13), Nipr. olv is a common Ni content found in primitive olivines (>

3000 ppm, e.g. Straub et al. 2011), and Nipm is the Ni content found in primitive mantle- derived magmas worldwide (150-250 ppm; Fig. 13; Schmidt & Jagoutz, 2017). Using these values to solve for the melt fraction, f, results in ~96% melt and only 4% crystal fractionation from the system. Thus, based on Ni contents in magmas from Manantial

Pelado, small amounts of fractionation have occurred and for most elements, in particular incompatible elements, the whole-rock data is a close approximation of the primitive mantle-derived melts. In addition, the near primary Ni contents in Manantial Pelado lavas 34 bulk rock Mg# range between 0.65 to 0.85 (Fig. 11). Such Mg# are in equilibrium with typical mantle lithologies further corroborating the primitive nature of these magmas

(Schmidt & Jagoutz, 2017).

Closed System Dynamics and Long-lived Storage While bulk rock compositions suggest little fractionation for some of the lavas erupted from Manantial Pelado and therefore are consistent with near primary magmas, olivine phenocryst compositions in these lavas appear at first sight far from such a primitive character. As noted above, most cores do not exceed Fo84. However, texturally these olivines are inconsistent with unmodified growth from a primitive liquid. Aside from a few larger glomerocrysts, olivine crystals are sub-euhedral grains that display relatively flat cores with weak normal zonation limited to the outermost rims of crystals

(Fig. 7 and 8) suggesting that normal zoning that develops during magma crystallization throughout the olivine has been potentially erased. Specifically, prolonged residence in the magma chamber inadvertently leads to diffusive equilibration within olivine grains.

Such diffusion can produce flat-cored olivines that show lower Fo content in the crystal’s center than it originally crystallized at as the entire crystal equilibrates with the remaining liquid (Roeder & Emslie, 1970; Lloyd et al. 2013). Implicit in this I assume that the system evolved under closed system conditions. This also requires that olivine crystallization proceeds significantly so that the remaining liquid is significantly depleted in Mg relative to its initial Mg melt content.

Diffusion equilibration and its reconstruction of initial core Fo contents can be

Ol/liquid explored using the distribution coefficient (KD ), the Fo content in the olivine, and the Mg# in the melt. I argue that on the basis of whole-rock consideration above (only 35

4% olivine has fractionated), the whole-rock is potentially representative melt composition of the initially crystallizing magma. Roeder & Emslie (1970) have provided

Ol/liquid the KD curve for typical crystallization and evolution of a system in equilibrium

Ol/liquid (KD = 0.3). Figure 11 shows the equilibrium curve with olivine and co-existing melt

Ol/liquid distributing Mg and Fe according to a KD = 0.3. Manantial Pelado basaltic andesite lavas fall above and to the left of the curve. One potential explanation for this disequilibrium could be the addition of Mg-rich mineral phases such as olivine. While such crystal accumulation could explain the vertical displacement from the equilibrium curve, there is no further textural or chemical evidence of olivine accumulation. Instead, diffusive equilibration proceeding during crystallization could explain the left-ward shift of Manantial Pelado lavas from the equilibrium curve. Considering a closed system with constant magma composition, the Fo content of the olivines will continue to change as

Fe-Mg interdiffusion continuously strives towards equilibrium as a result creates flat cores. Using the equilibrium curve, I estimate potential olivine core compositions prior to diffusive equilibration. Potential original Fo contents of the olivine may be as high as

Fo~88-90, which is only minimally more evolved than what is typically considered primitive.

Further evidence for re-equilibration of the system is suggested through Ni content within olivine. Basaltic andesite lavas from Manantial Pelado continuously erupted the same composition throughout its long history. If solely olivine fractionation occurred, Ni trends from within olivine phenocrysts should follow a single liquid-line of descent (Fig. 12; Ruprecht & Plank, 2013); however, Ni from Manantial Pelado magmas are elevated for a given Fo content relative to a fractionation trend originating from a 36 peridotite source (Fig. 12). Diffusive equilibration can explain this pattern of elevated Ni and specific Fo contents. During fractionation Mg-Fe and Ni are removed from the liquid. However, Ni fractionates more effectively, which can be seen through the initial rapid decrease in Ni, while Fo contents change slowly. The small, but noticeable different behavior of Mg-Fe and Ni leads to a curved fractionation path. Diffusive equilibrium after this path has emerged will move the average composition to high Ni relative to the fractionation path. Not only does this evidence suggest a long-lived and closed system, but also points towards an originally more primitive system. Currently the Ni in olivine peaks at 2100 ppm, but with re-equilibration and fractionation of olivine, it is clear that the Ni content could have been as high as >2100 ppm and maybe as high as 3000 ppm

(Fig. 12).

In summary, Schmidt & Jagoutz (2017) claim 150-250 ppm Ni is indicative of primitive compositions. Manantial Pelado data plots near the more primitive end-member of regional Ni data in the area (Fig. 13) and only 4% olivine fractionation is needed to explain the difference between truly primitive compositions and most of Manantial

Pelado basaltic andesites. In the TSVZ Manantial Pelado samples are among the most primitive, and the few samples in Figure 13 that show high MgO contents of 11-16 wt% are exclusively from the southernmost segment of the SVZ where the crust is much thinner compared to the TSVZ where primitive magmas can reach the surface easily uninterrupted. Diffusive equilibration within olivine suggests these phenocrysts were once near Fo 90, and Fo ≥ 90 is considered primitive (Straub et al. 2008). To further support a more primitive nature of Manantial Pelado lavas, Cr-spinels are present (Fig.

7). Cr-spinel phenocrysts crystallize exclusively early while Cr contents are high and 37 melts are primitive prior to clinopyroxene crystallization, which takes up Cr later along the liquid line of descent and prevents the continued formation of Cr-spinel (Clynne &

Borg, 1997). Textural and geochemical evidence shows Manantial Pelado basaltic andesite was once more primitive than their already somewhat primitive compositions due to their long-lived storage in the system which allowed for re-equilibration.

Figure 11. Fo (host olivine) vs Mg# (whole rock) plotted with the melt-liquid equilibrium line (KD = 0.3) which is calculated through Mg-Fe partitioning from olivine into the liquid melt (Lloyd et al. 2013; and Roeder & Emslie, 1970). Circle = basaltic andesite lavas; Diamond = basaltic andesite dike; Triangle = basaltic andesite unconformable unit. Dotted lines represent samples path away from equilibrium due to diffusive equilibration, and suggests previously elevated Fo (host olivine) in the core. 39

Figure 12. Fo (olivine) vs Ni (olivine) diagram taken from Ruprecht & Plank (2013). Previously used for Irazu data (grey diamonds) for assessing mixing processes (pyroxenite vs peridotite source). Black squares = Manantial Pelado basaltic andesite lavas.Black lines indicate channel for simple fractionation and each tick mark is 1% crystallization. Manantial Pelado data plots at abnormally elevated Ni content for the corresponding Fo content. Red circles indicate potential previous location for Manantial Pelado data prior to diffusive equilibration (Fo 90) and falls down to Fo 87 where current data sits after 4% olivine fractionation (4 tick marks).

Figure 13. MgO wt% vs Ni ppm whole-rock data. (Color scheme is that of Figure 4). Black bracket indicates primitive composition based on Schmidt & Jagoutz (2017). 41

Source Variation The goal of this study is to use magmas from Manantial Pelado to provide new constraints for the primitive magmas in the TSVZ. Aside from the chemical characterization and establishing a primitive baseline, understanding the petrogenetic processes is important to understand how melts are generated in the mantle. Whether melts are derived solely by flux melting or are also the product of decompression melting is still not fully understood (Grove et al. 2002; Schmidt & Jagoutz, 2017). While all three lithologies from Manantial Pelado are considered calc-alkaline, which is typically interpreted to be the result of flux melting, there is sufficient evidence that points towards potential source variation between and within the lithologies. In regards to the basaltic andesite as it compares to the aphyric and plagioclase andesite (Fig. 4), the latter two plot as high-K trachyandesite in true calc-alkaline compositions while the basaltic andesite plots much lower in K near the low-K tholeiite boundary (Fig. 4). Trace element data for the basaltic andesite displays typical subduction zone characteristics, however, comparable calc-alkaline basalts, both global and regional, display an elevated enrichment in LILE and LREE, MREE, and HREE in comparison to the basaltic andesite which plots closer to tholeiitic compositions (Fig. 6a,b,c). Variation within the different lithologies could be a result of source variation, but the lithologies could also be genetically related. To test this relationship, a comparison of the melt composition of the basaltic andesite to the whole-rock data of the apyhric andesite (essentially all glass) will estimate the possibility of a genetic relationship. 42

Melt Composition Calculation While the whole-rock data displays a large compositional gap and suggests potential source variation, using mineral scale data with whole-rock compositions can be used to calculate their genetic relationship. The aphyric andesite and basaltic andesite could be genetically unrelated as they may have originated from different sources or at least display varying melting methods. The andesites may be more directly related to the typical subduction zone magmatism where dehydration of the slab drives partial melting in the mantle wedge creating basalt that then rises to the surface and differentiates. In contrast, the basaltic andesite may be derived from decompression melting in the mantle wedge related to some upward vector in the convecting mantle. It has been shown for other arcs that both melting mechanisms may co-exist (Grove et al. 2002). However, this does not address how the aphyric andesite is actually formed, and it begs the question if it is realistic to have two different sources reach the same center and alternate eruptions.

In order to test this relationship, the melt composition of the basaltic andesite was calculated using a mass-balance equation based off of the whole-rock and EMP data sets

elem elem (XWR -(Fmin*Xmin )). JMicroVision was used to quantitatively estimate phenocryst phase percentages (Fmin). Anything below 300 µm was not considered a main phenocryst and determined groundmass. Image analysis (using MP-17-33 as basaltic andesite starting composition) resulted in 12% olivine and 15% plagioclase phenocrysts. This is a minimum estimate of the crystals that needs to be removed. In addition, small amounts of clinopyroxene and spinel may also have been removed. If the aphyric andesite and basaltic andesite are genetically related and their compositional gap is from efficient differentiation, then the residual melt composition of the basaltic andesite should be 43 comparable to the aphyric andesite whole-rock XRF composition since it is a glass and therefore melt.

Good agreement between calculated residual melt compositions and the aphyric andesite can be achieved. For example, after removing the main phenocryst phases from the basaltic andesite, the calculated melt Mg# is 28 compared to 34 for the aphyric andesite. Other major elements are matched to within 3%. However, the calculation requires significantly more removal of plagioclase (35%), which is greater than the estimated plagioclase crystallization based on BSE images. Furthermore, I used ~12% olivine crystallization consistent with the results from the BSE images. Minor amounts of clinopyroxene (2%) and spinel (~1%) are also required. The good match suggests that these two lithologies could be genetically related through differentiation and fractionation of ~47% crystals.

Crystal mushes typically reach rheologic lock up at crystal contents >60%

(Marsh, 1988). The reduced mobility may facilitate the extraction of a more evolved melt lens cap (Dufek & Bachmann, 2010). Such a melt lens may be represented by the aphyric andesites. Thus while Manantial Pelado mostly generated homogenous basaltic andesite, intermittently an increase in crystallization (to 47% or higher) may have slowed convection and occasionally allowed the formation of an evolved, crystal-poor, melt lens, and the eruption of the aphyric andesite. Likely, the system resumed to the normal mode of generating homogenous basaltic andesite with lowered crystallization.

Further support for efficient differentiation is through the spider diagram (Fig. 6a) where the evolved andesites are all consistently elevated above the basaltic andesite which is a typical result of fractionation within the system. The enrichment of 44 incompatible trace elements in the aphyric andesites relative to the basaltic andesites requires also approximately crystal fractionation of ~54% (estimated using the relationship of CL /C0 = 1/f for incompatible elements, where CL is the aphyric andesite and C0 is the basaltic andesite).

Aphyric andesites are rare in the glacially carved valleys (Fig. 1C). Manantial

Pelado consistently erupts a homogenous lithology of basaltic andesite that is only interrupted several times by the more evolved, crystal-poor, andesite lavas, and to reach the desired melt Mg# within the basaltic andesite, increased crystallization was required.

This could suggest that a mush system occurred infrequently for Manantial Pelado.

Evidence for source variation within the basaltic andesite lithology itself, is seen through major element plots. The FeO* vs MgO (Fig. 5) displays two trends of evolution: one with initial Fe-enrichment and the other with Fe-depletion towards the pure andesite samples. The Fe-enrichment trend is typical of tholeiitic lavas due to its more reducing environment and dryer conditions related to decompression melting, which suppresses the crystallization of Fe-oxides such as magnetite and facilitates plagioclase crystallization resulting in an Fe-enrichment (Zimmer et al. 2010). The Fe-depletion trend on the other hand, is typical of calc-alkaline environments that are considered to be the result of wet conditions induced by fluid-flux melting and is a signature for magma generation in subduction zones (Zimmer et al. 2010). The result is the early crystallization of Fe-bearing oxides and the suppression of plagioclase crystallization leading to Fe depletion as the system evolves. Thus, the main difference in tholeiitic versus calc-alkaline magmas is the early presence of oxides or plagioclase. If plagioclase is fractionated other elements are likely affected as well that are compatible in 45

plagioclase, such as CaO, Sr, and Al2O3. Samples MP-17-02, 05 both exhibit elevated

CaO, Sr, Al2O3 concentrations at ~5.22 and 5.27 MgO respectively, while also displaying strong Fe depletion (Fig. 5). Enriched CaO, Sr, and Al2O3 suggests plagioclase suppression which occurs with elevated water concentrations (Sisson & Grove, 1993).

Ultimately, a slight variation in magma generation within the basaltic andesite samples has presented itself within the major and trace elements. A further look into this variation can be achieved through understanding the oxidation state of the system.

Oxygen Fugacity Understanding the oxygen fugacity (fO2) constraint within a system contributes to the overall characteristics of the reservoir as being in either oxidizing or reducing environments. Oxygen fugacity represents the partial pressure of oxygen within a system which determines oxidation states of certain elements and thus mineral crystallization.

Oxygen fugacity of the basaltic andesite was calculated using an Fe-Ti two-oxide geothermometer from Ghiorso and Evans (2008). High-precision electron microprobe measurements were made on ilmenite-magnetite pairs within four basaltic andesite lavas

(MP-17-25, 29, 33, 36). “Pairs” refers to ilmenite and magnetite phases within close proximity of each other and some are noted as touching pairs. To ensure quality measurements were made and oxide pairs were in equilibrium, only pairs also in Mg/Mn equilibrium were considered (Bacon & Hirschmann, 1988). After equilibrium calculations were made, eight pairs from three samples (MP-17-29, 33, 36) were adequate. The Fe-Ti two-oxide thermometer provides a minimum temperature for the magma reservoir as the oxides likely represent late-stage crystallization as they only occur in the matrix (Fig. 5, 10), and they are relatively small, which results in fast 46 diffusive equilibration (Freer & Hauptmann, 1978). Manantial Pelado lavas displayed a minimum crystallization temperature range of 723-991°C (Fig. 14). The majority of the pairs display a range in fO2 between NNO -0.5 to NNO +0.5. Compared to Volcán

Quizapú, Manantial Pelado shows more reducing conditions with Quizapú magmas overall falling near NNO+1 (Fig. 14; Ruprecht & Bachmann, 2010; Ruprecht, et al.

2012). Typical subduction zones exhibit more oxidized conditions due to the subduction of sediments, and more reduced environments are typical of MORB settings (Kelley &

Cottrell, 2009). A more reduced fugacity of Manantial Pelado relative to Quizapú suggests a slightly more MORB-like signature. A significant difference between subduction and MORB environments is their water content – this potentially suggests

Manantial Pelado lavas may be dryer than typical arc lavas should be. A lower fugacity and therefore more reduced conditions of Manantial Pelado compared to Quizapú is one further step of evidence towards a potential mixture of sources for these lavas and that melting may not have been fully dominated by fluid-flux melting but also incorporates a significant amount of decompression melting to leave its signature.

Figure 14. Temperature vs oxygen fugacity diagram calculated from Fe-Ti two- oxide geothermometer (Ghiorso & Evans, 2008). Quizapu data is from both of the most recent and largest historic eruptions (1846-47, 1932) (Ruprecht et al. 2012). Manantial Pelado data plots lower (and therefore more reduced) relatice to the Quizapu data. 48

Hygrometers As described above, a fundamental parameter that controls magma evolution in arcs is the dissolved water content that strongly affects the crystallization sequence (e.g.,

Zimmer et al. 2010). Estimating the water content in primitive magmas has been pursued with various techniques. The most common uses melt inclusions hosted in mineral phases, commonly olivine (e.g. Wallace, 2005). However, it has been recently shown that volatile estimates from melt inclusions in slowly cooled lavas or even large clast tephra samples underestimates water contents significantly (e.g. Gaetani et al. 2012 , Lloyd et al.

2013 ). Thus, other means to determine pre-eruptive volatile contents are required for

Manantial Pelado lavas.

Zimmer et al. (2010) published a compilation of melt inclusions in Aleutian volcanoes that they linked to major element liquid lines of descent and therefore provide relationships that may be applied to other systems assuming that magma evolution is following a single fractionation path. For the Aleutians they parameterized the Fe enrichment with decreasing MgO as a function of dissolved H2O in what they call the tholeiitic index (THI). In particular, the tholeiitic index compares the FeO* content at 4 wt% MgO to FeO* content at 8 wt% MgO. If the resulting ratio (THI=FeO4.0/FeO8.0) is greater than 1 they consider such magmas tholeiitic and magma series with a THI less than 1 are calc-alkaline. They tested this concept against a global arc database of melt inclusions and showed the Fe enrichment or depletion encapsulated in the tholeiitic index is robust and that water content in the melt controls the Fe enrichment. Thus, one may be able to estimate pre-eruptive water content for magma series that span a range of MgO contents of ~ 4-8 wt%. Manantial Pelado basaltic andesites vary almost of such a range in 49

MgO and they show correlated variations in FeO* that suggest a more variable water content (Fig. 5). While some samples suggest Fe enrichment due to drier conditions, others seem to support wet magma evolution. An upper bound for the most extreme tholeiitic index at Manantial Pelado (THI=1.12, Fig. 5) would suggest a minimum water content of ~1.54 wt% H2O using the parameterization of Zimmer et al. (2010); H2O

(wt%)=exp((1.26-THI)/0.32). This result hinges significantly on the cinder cone samples, which are not the most common magmas in the Manantial Pelado vicinity. They are defining the low MgO end of that trend and excluding them makes estimates significantly more uncertain as the slope becomes less well defined. Nonetheless, given the variability in Manantial Pelado samples and whether the cinder cone data is used, this THI may represent a minimum H2O estimate. This method assumes that magmas are part of a liquid line of descent where all samples are directly related by fractional crystallization and clearly some samples show early Fe depletion and therefore follow a different differentiation pathway. Other independent methods do not require this assumption.

Another method to estimate water contents uses the first order distribution of Ca and Na between melt and co-existing plagioclase. (Lange et al. 2009; Waters and Lange,

2015). Not only does water suppress plagioclase crystallization in general, it also shifts plagioclase An contents in equilibrium with a melt to high An contents (e.g. Sisson &

Grove, 1993). In the case of the plagioclase-liquid hygrometers from Lange et al. (2009) and Waters & Lange (2015) a quantitative approach utilizing thermodynamic equations constraints and has been developed. The models are built upon the crystal-liquid exchange reaction between anorthite and albite. The 2009 model is calibrated using 45 hydrous and 26 anhydrous plagioclase-liquid experiments with three filters applied with 50

respect to crystallinity, H2O fluid saturation, and compositional totals (Lange et al. 2009).

The model is constrained within liquid compositions (46-74 wt% SiO2), plagioclase compositions (An37-An93), temperatures (825-1230°C), pressures (0-300 MPa), and dissolved melt water concentrations (0-7 wt% H2O) with a standard error of ~0.32 wt%

H2O. The 2015 model expands its data set using 214 experiments (107 are hydrous, 107 are anhydrous). This new version added a fourth filter of melt viscosities (≤ 5.2 log10

Pa·s), and slightly altered previous parameters such as liquid compositions (45-80 wt%

SiO2; 1-10 wt% K2O), plagioclase composition (An17-95), temperature (750-1244°C), pressure (0-350 MPa), and H2O content (0-8.3 wt%) with a standard error estimate at

~0.35 wt% H2O.

Therefore, this method may provide potentially more accurate and reliable H2O estimates for Manantial Pelado magmas. Both the 2009 and 2015 models from Lange and

Lange & Waters require the anorthite content of plagioclase co-existing with a melt composition in equilibrium with this plagioclase, and independently determined temperature and pressure estimates. Melt compositions are hard to estimate for Manantial

Pelado (with the exception of the aphyric andesites), in particular for the cores of plagioclase crystals that grew from a more primitive melt than the current matrix.

Since these lavas in this study are mostly crystallized, glass compositions have not been obtained. However, the lack of significant Eu anomaly in most of the basaltic andesites (Fig. 6) indicates that plagioclase fractionation in these samples is minimal.

Assuming a closed system, as argued previously, then allows me to use the whole rock compositions as liquid representatives. Moreover given the slow diffusive re- equilibration of major elements in plagioclase (Grove et al. 1984; coupled Ca-Al and Na- 51

Si diffusion) I assume that original plagioclase core composition during early crystallization are retained. As a result, one can use the whole rock-plagioclase pair to estimate water content via this hygrometer. A representative basaltic andesite composition (MP-17-33) was used for the liquid composition in both models. Anorthite content was taken from electron microprobe data of plagioclase phases within the same sample. Temperature and pressure estimates were acquired through MELTS software, which will be explained below. The first set of parameters tested were the following:

T=1171°C (liquidus temperature from MELTS), P=505 MPa, XAn=0.86. The 2009 model calculated 2.3 wt% H2O while the 2015 model calculated 1.4 wt% H2O. This initial data is reasonable based on the phase assemblage of the basaltic andesite

(plg>ol>cpx>opx). The second set of parameters tested involved only a slight change in the temperature (T=1110°C) which represents the amount cooling and crystallization necessary (~25-30%) to match sample MP-17-33’s crystallinity. This change in temperature raises the estimate to 3.0 wt% H2O for the 2009 model and 2.3 wt% H2O for the 2015 model. While the variance between the models lies outside of both their standard error estimates, they both display an increase in water content as crystallization and cooling occurs. This aligns with fractional crystallization processes as water responds incompatibly and stays in the melt. A change from XAn=0.86 to XAn=0.80 drops the water content by 0.6 wt%; however, a drop in the pressure from 505 MPa to 405 MPa does not affect the water percentage at all. Both temperature and compositional data highly affect water content while pressure has minimal influence.

A third independent hygrometer that may be applied in similar ways to the plagioclase-liquid hygrometer, is the calcium-in-olivine geohygrometer (Gavrilenko et al. 52

2016). This method is based on CaO partitioning into the olivine and co-existing liquid and how that partitioning is influenced by the presence of water (Gavrilenko et al. 2016;

Feig et al. 2006). As water in the melt increases, Ca becomes complex with hydrogen in the melt reducing its partitioning into olivine. This was addressed by comparing subduction zone olivines with MORB setting (dry) olivine as well as experimentally with

Ol/L anhydrous olivine (Gavrilenko et al. 2016). Experimental results displayed how DCaO

Ol/L (partition coefficient of CaO into olivine and liquid; DCaO =CaOolivine/CaOliquid(WR)) should behave in a dry system (Fig. 15a), anything below that curve suggests the addition of water. Gavrilenko et al. (2016) parameterized the effect of water by comparing

Ol/L theoretical dry partition coefficients (DCaO ) with actually observed partition coefficients in the sample. The shift in this partitioning behavior can be estimated to first order with a linear regression (Fig. 15b). Once the observed Ca partitioning for a given melt MgO content is determined, one can calculate a water content estimate. This method requires high-precision electron microprobe analyses of olivine grains to determine Ca in olivine to sufficient precision. Identical to the above discussion true co-existing melt compositions are lacking and we assume that for the olivine cores whole-rock data can approximate the original melt Ca content. Note, that as only 4% olivine fractionation occurred for the most primitive basaltic andesites and therefore the bulk whole-rock composition represents a good estimate for the primitive melt Ca content, especially given that neither calcic plagioclase nor clinopyroxene are likely to crystallize prior to olivine. Applying this concept to samples from Manantial Pelado results in a range of

3.8-5.3 wt% H2O (Fig. 15b). 53

In summary, a range in water content varied from ~1.54-5.3 wt% H2O depending on the hygrometer or method used. This range would suggest that Manantial Pelado covers most of the range in water content for arc magmas (Plank et al. 2013). Either some of the assumptions are not valid resulting in a narrower range in pre-eruptive water contents or this range is a true reflection of melts at Manantial Pelado. In fact, the variability in major and trace elements paired with the estimated oxygen fugacity suggested there might be varying water contents in these lavas as a result of varying magma generation methods (fluid-flux vs decompression melting) under Manantial

Pelado. Using a variation of techniques and methods, multiple results point toward a slight source variation within the basaltic andesite in that partial tholeiitic and drier magmas as a result of decompression melting may have been incorporated into this system. Constraining the water content and magma source generation are fundamental controls in how a system behaves and evolves and are primary parameters to fully understand. To fully answer this question other constraints may be brought to bear such as isotope data.

Ol/L Figure 15. DCaO figure of Manantial Pelado basaltic andesite samples for water estimates from Gavrilenko – CaO-in-olivine geohygrometer (Gavrilenko Ol/L et al. 2016). A) Initial plot required to calculate ∆ DCaO (dry-wet). B) H2O Ol/L estimate from DCaO .

MELTS Several methods have been used to estimate water content, temperature constraints, and oxygen fugacity constraints of Manantial Pelado. While many times a range of constraints were produced, using MELTS software is another technique that can refine these constraints to more realistic estimates and aid in estimating pressure conditions. MELTS software provides thermodynamic modeling for phase equilibria in magmatic systems. The software is applicable to a wide variety of systems both hydrous and anhydrous over a temperature range 500-2000°C and pressure range 0-2 GPa

(Ghiorso et al. 1995). However, it has limitations with intermediate systems that consist of hornblende and biotite, and does not perform as accurately at very shallow depths.

This software assumes equilibrium within the system, yet some versions have the ability to perform fractional crystallization, assimilation, and degassing of volatiles. Bulk whole- rock data is used for compositional input, and several other variables should be specified such as temperature, pressure, and oxygen fugacity in order to model igneous processes and output appropriate phase assemblages. MELTS contains several different models within itself as well, and it is important to select the correct model for the system of interest. pMELTS is a revised calibration that specializes in “mantle-like” bulk compositions and can withstand elevated pressures more easily (Ghiroso et al. 2002).

For Manantial Pelado data, pMELTS was used. Although some samples range into intermediate compositions, hornblende and biotite are not present phases. A representative basaltic andesite was selected for the bulk composition and based on phase assemblage an estimate of 500 MPa was used to represent intermediate to shallow depths.

The crustal thickness around Manantial Pelado is ~55 km. Pressures of 500 MPa is ~15- 56

20 km representing the hypothesized intermediate depth of the reservoir. From a combination of hygrometers - plagioclase-liquid (Lange et al. 2009 & 2015); THI figure and calculation (Zimmer et al. 2010); Ca-in-olivine (Gavrilenko et al. 2016) – a range from 1.5-5.3 wt% H2O was reported. The Fe-Ti two-oxide thermometer paired with

Mg/Mn equilibration was used to estimate a minimum temperature range from 723-

991°C, as well as an fO2 ~ NNO +0. These constraints paired with whole-rock data was used to estimate pressure constraints and phase assemblage. The range of constraints will be used to get the most representative phase assemblage of Manantial Pelado basaltic andesite lavas and will further constrain these estimates to provide a better hypothesis of this reservoir’s characteristics.

CONCLUSION A variety of methods and calculations were used to characterize Manantial

Pelado. Whole-rock compositions paired with mineral-scale data provided reservoir constraints and insight into magma chamber processes. Manantial Pelado’s dominant lithology, basaltic andesite, displayed primitive compositions through presence of cr- spinels and elevated Fo and Ni content. Through understanding the amount of fractionation and equilibration of the system, Manantial Pelado proved to be more primitive than initial results suggested. Connecting geohygrometers and thermometers with whole-rock data, we were able to suggest a potential variation in magma source generation between fluid-flux melting and decompression melting. Narrowing down the range of constraints through MELTS will provide a better understanding of this reservoir.

Understanding the source and water content significantly affects magma chamber dynamics and explosivity of eruptions. 57

In an area surrounded by active, silicic, explosive volcanism, further characterization of primitive vents that could contribute to feeding these upper crustal systems is crucial in understanding eruption dynamics and understanding the temporal evolution of volcanic systems. Now that initial characteristics and constraints have been made on Manantial Pelado, we can start to estimate how it fits into the SVZ MASH model. A MASH zone results in new magma generation, homogenization, and evolution of a system that restricts primitive basalts from reaching the surface. Although, Manantial

Pelado does erupt a significant amount of homogenous material throughout its history, the main lithologies are not highly evolved and do not display evident mixing trends.

Phenocrysts do not prove to be foreign, but to fully claim that isotope data would be necessary. Additionally, although Manantial Pelado does not erupt pure primitive basalt, it does generate truly primitive material as basaltic andesite. The MASH model claims primitive basalts have yet to be found in the SVZ, and yet Manantial Pelado produces near primitive material. For that reason, magma generation for Manantial Pelado may have only briefly encountered the MASH zone at the crust-mantle boundary (potentially the MASH body fades out and Manantial Pelado sits on its fringe), or was only briefly stored in this zone prior to ascending to its own magmatic reservoir (Fig. 16). The homogenous character is a result of its short lifetime in the MASH zone and continually feeds well-mixed, but still primitive, material to elevated chambers as a result. From the

MASH zone, magmas became buoyant again and establish their own reservoir where long-term storage and diffusive equilibration within its own closed-system chamber could occur. Within this chamber is where a possible mush-like process would occur to create the evolved, crystal-poor aphyric andesites intermittently throughout its history (Fig. 16). 58

Previously, little to no research had been done on the primitive vents (specifically the longer-lived and larger systems) in this area, but with the use of textural, whole-rock and mineral data, and modeling methods, we were able to provide insight into crystal- melt relationships, petrogenesis processes, and establish a primitive baseline for

Manantial Pelado that proves to be even more primitive than initial data suggests. 59

Figure 16. Manantial Pelado magmatic reservoir schematic. Displays source variation methods between tholeittic (THO), decompression melting (Decomp. melting) and calc-alkaline (CA), fluid-flux melting. As the partial melts become too buoyant and ascend to the crust-mantle boundary, the magmas are briefly stored in the hypothesized MASH zone. The magmas continue to ascend into their own magmatic reservoir where long-term storage and diffusive equilibration can occur. Occasionally, crystallization increases and results in an evolved, crystal-poor melt lens (white-dashed line). Primarily, homogenized basaltic andesite erupts, but intermittent melt lenses of apyhric andesite will erupt. The brief storage in the MASH zone results in homogenized yet still primitive material. Manantial Pelado may sit on the fringe of the MASH zone which is why brief storage can be achieved, as opposed to the DG-CA Volcanic Complex which may sit above the standard MASH zone. (MP: Manantial Pelado; DG: Descabezado Gande; VQ: Quizapu; CA: Cerro Azul)

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APPENDIX

Table A1. Unnormalized whole-rock XRF+ICPMS major and trace data. Major element oxides in weight %, trace elements in parts per million (ppm).

MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- Sample 01 02 03 04 05 08 09 15 22bh 22be XRF

SiO2 52.49 53.44 53.24 52.62 52.96 60.73 52.32 60.40 61.65 53.86

TiO2 0.70 0.79 0.69 0.69 0.79 1.34 0.93 1.36 1.30 0.76

Al2O3 17.78 19.09 17.46 17.81 19.08 16.06 18.64 16.14 16.01 17.35 FeO* 7.51 7.30 7.43 7.48 7.34 6.73 8.25 6.95 6.40 7.29 MnO 0.14 0.14 0.13 0.14 0.14 0.14 0.14 0.15 0.14 0.13 MgO 6.93 5.20 7.03 7.37 5.24 1.99 5.82 2.10 1.75 6.65 CaO 9.41 9.27 9.05 9.43 9.50 4.48 9.04 4.63 4.03 8.35

Na2O 2.92 3.26 3.02 2.94 3.23 5.03 3.48 4.83 5.11 3.36

K2O 0.94 0.91 1.02 0.90 0.90 2.46 0.84 2.41 2.61 1.10

P2O5 0.15 0.16 0.15 0.14 0.16 0.53 0.17 0.56 0.50 0.19 Sum 98.97 99.56 99.23 99.52 99.33 99.49 99.63 99.53 99.51 99.05 Ni 70 31 78 85 33 2 60 2 4 72 Cr 169 70 203 221 73 0 99 0 3 189 Sc 28 29 26 26 28 17 26 19 17 25 V 201 237 200 198 234 97 220 103 65 194 Ba 243 252 254 259 252 540 286 531 578 336 Rb 20 18 24 17 17 71 14 70 76 23 Sr 702 720 682 699 736 400 644 407 387 747 Zr 64 64 66 63 65 205 75 203 217 79 Y 14 17 14 14 17 31 18 32 36 15 Nb 2 2 2 2 2 7 1 7 8 2 Ga 18 19 18 19 20 20 21 20 20 18 Cu 82 96 61 89 92 15 94 17 12 10 Zn 64 73 65 67 69 94 75 98 97 78 Pb 9 12 8 9 9 15 7 15 15 10 La 9 10 13 15 11 25 12 24 27 13 Ce 23 24 23 21 26 60 25 60 61 26 Th 3 4 4 3 3 9 4 9 9 4 Nd 13 13 13 12 13 31 15 31 32 18 U 4 1 2 3 2 2 1 2 3 2 ICP-MS La 10.63 10.73 10.95 10.46 11.22 26.07 10.53 25.85 29.00 13.39

Ce2 22.95 23.25 23.18 22.52 23.75 57.97 22.90 57.73 61.97 28.13 Pr 3.08 3.15 3.13 3.01 3.23 7.71 3.18 7.69 8.23 3.81 Nd 13.18 13.70 13.36 13.05 14.01 32.33 13.98 32.60 34.74 15.98 Sm 3.09 3.28 3.13 3.08 3.40 7.48 3.48 7.51 7.86 3.60 Eu 0.98 1.07 0.97 0.96 1.08 1.91 1.16 1.93 2.00 1.10 Gd 2.82 3.05 2.85 2.79 3.16 6.80 3.39 6.91 7.23 3.17 Tb 0.44 0.50 0.45 0.44 0.51 1.06 0.54 1.08 1.12 0.49 Er 1.53 1.84 1.52 1.52 1.89 3.26 1.84 3.33 3.53 1.65 70

MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- Sample 01 02 03 04 05 08 09 15 22bh 22be Tm 0.22 0.27 0.23 0.22 0.28 0.46 0.27 0.47 0.50 0.24 Yb 1.40 1.75 1.41 1.39 1.77 2.92 1.64 2.92 3.13 1.50 Lu 0.22 0.28 0.22 0.22 0.29 0.45 0.26 0.45 0.50 0.23 Ba 240.29 246.01 250.42 256.92 247.54 540.04 281.11 533.78 583.24 331.74 Th 3.40 2.98 3.76 3.42 3.00 8.26 2.61 8.10 8.80 3.63 Nb 1.74 1.71 1.85 1.73 1.73 7.11 2.21 6.98 7.67 2.59 Y 14.31 16.79 14.43 14.19 17.48 31.98 17.56 32.29 35.40 15.59 Hf 1.84 1.86 1.86 1.82 1.90 5.68 2.18 5.60 6.05 2.21 Ta 0.14 0.13 0.15 0.14 0.13 0.52 0.17 0.51 0.55 0.19 U 0.95 0.82 1.07 0.93 0.81 2.20 0.71 2.15 2.32 1.00 Pb 8.30 11.95 7.85 8.48 8.15 14.44 6.56 14.37 14.63 8.98 Rb 18.17 16.85 23.18 16.44 15.76 71.00 13.08 69.28 74.16 22.30 Cs 1.07 0.37 0.67 0.89 0.97 3.56 0.62 3.48 2.86 1.08 Sr 705.33 723.35 684.08 702.65 737.79 404.64 653.03 417.32 393.50 759.64 Sc 27.13 30.39 26.86 27.04 30.19 17.49 26.28 18.12 16.54 25.06 Zr 62.61 62.78 64.17 61.49 63.11 212.09 75.66 209.33 224.05 79.37 71

MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- Sample 25 26a-S1 26c 29 31 33a/b 36 40 44a XRF

SiO2 53.43 53.99 54.04 53.30 52.18 53.09 52.74 61.26 64.02

TiO2 0.92 1.08 1.08 0.75 0.70 0.77 0.77 1.35 0.97

Al2O3 17.95 17.86 17.82 18.30 17.85 18.34 18.29 16.03 15.83 FeO* 8.10 8.52 8.38 7.75 7.62 7.76 8.00 6.54 5.56 MnO 0.14 0.15 0.14 0.14 0.14 0.14 0.14 0.14 0.14 MgO 5.31 4.20 4.32 6.37 7.40 6.25 6.54 1.79 1.17 CaO 8.93 8.15 8.36 8.39 9.40 8.46 8.46 4.17 3.09

Na2O 3.40 3.72 3.94 3.33 2.93 3.29 3.28 5.07 5.37

K2O 1.00 1.09 1.10 0.98 0.87 0.99 0.89 2.56 3.00

P2O5 0.18 0.22 0.23 0.14 0.14 0.15 0.16 0.54 0.31 Sum 99.34 98.98 99.42 99.46 99.23 99.23 99.27 99.44 99.46 Ni 41 21 22 74 86 72 77 1 2 Cr 81 45 47 106 218 104 106 0 1 Sc 27 25 25 26 26 26 26 16 14 V 217 217 231 207 198 213 217 73 27 Ba 268 319 312 245 252 252 238 562 645 Rb 21 25 25 22 18 21 18 72 89 Sr 515 603 605 691 710 695 695 393 324 Zr 93 100 99 66 64 67 64 216 249 Y 17 19 19 15 14 16 16 32 33 Nb 3 2 3 2 1 2 2 7 8 Ga 18 20 20 19 19 20 19 19 21 Cu 102 91 85 71 82 93 105 10 11 Zn 76 84 82 70 67 70 72 90 93 Pb 7 10 10 6 8 7 6 14 18 La 11 12 12 10 11 9 9 25 28 Ce 27 33 30 23 23 27 23 59 65 Th 4 3 4 3 3 3 3 9 10 Nd 13 18 18 13 12 11 13 34 35 U 1 3 2 0 3 1 1 1 3 ICP-MS La 11.13 13.61 13.41 10.18 10.70 10.66 10.38 27.17 29.44

Ce2 24.83 30.29 29.77 21.79 22.72 22.95 22.19 60.92 63.82 Pr 3.34 4.08 4.02 2.93 3.07 3.10 3.05 8.04 8.23 Nd 14.46 17.44 17.21 12.86 13.18 13.56 13.25 33.94 33.98 Sm 3.60 4.18 4.16 3.04 3.10 3.25 3.23 7.98 7.92 Eu 1.10 1.32 1.29 0.98 0.96 1.04 1.06 2.00 1.92 Gd 3.41 3.86 3.82 2.87 2.77 2.97 3.05 7.01 6.82 Tb 0.56 0.61 0.61 0.46 0.43 0.48 0.48 1.11 1.09 Er 1.86 1.94 1.90 1.74 1.58 1.78 1.74 3.39 3.54 72

MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- MP-17- Sample 25 26a-S1 26c 29 31 33a/b 36 40 44a Tm 0.26 0.27 0.27 0.24 0.22 0.26 0.26 0.49 0.51 Yb 1.64 1.69 1.66 1.58 1.42 1.62 1.63 2.94 3.25 Lu 0.26 0.27 0.26 0.26 0.23 0.27 0.27 0.46 0.52 Ba 267.64 312.52 308.94 245.68 251.74 257.37 240.07 570.37 657.46 Th 3.08 3.72 3.68 3.20 3.42 3.32 2.68 8.62 10.15 Nb 2.67 3.31 3.31 1.81 1.78 1.89 1.76 7.43 8.34 Y 17.45 18.72 18.33 15.37 14.42 16.38 16.13 32.55 34.02 Hf 2.60 2.78 2.76 1.83 1.88 1.91 1.81 5.94 6.89 Ta 0.19 0.23 0.22 0.14 0.14 0.15 0.13 0.53 0.59 U 0.76 1.03 1.05 0.87 0.91 0.88 0.73 2.26 2.68 Pb 7.87 9.85 9.58 6.19 9.23 6.87 5.87 14.83 17.65 Rb 20.42 25.24 24.14 22.46 16.62 19.79 16.57 71.87 88.22 Cs 0.82 1.49 1.43 0.73 1.04 0.98 0.60 2.91 4.64 Sr 528.96 616.18 614.51 686.12 711.60 699.59 704.44 385.95 324.02 Sc 28.07 27.04 26.57 24.87 26.96 25.30 25.82 16.41 14.09 Zr 93.60 101.17 100.28 63.38 61.73 65.61 62.41 218.54 256.13 73

Table A2. Oregon State University electron microprobe olivine data in oxide weight% from samples: MP-17-01, 02, 25, 29, 33, 36.

Sample SiO2 Al2O3 MnO FeO NiO Na2O MgO Cr2O3 TiO2 Mp-17-01 oliv1 39.33 0.029 0.202 15.25 0.208 0.000 44.71 0.022 0.003 Mp-17-01 oliv1 39.07 0.031 0.241 16.16 0.189 0.008 44.15 0.099 0.000 Mp-17-01 oliv1 37.65 0.021 0.376 22.21 0.106 0.008 39.00 0.013 0.007 Mp-17-01 oliv2 37.00 0.040 0.457 24.60 0.074 0.006 36.77 0.004 0.005 Mp-17-01 oliv2 55.81 24.570 0.041 2.42 0.019 5.788 2.31 0.001 0.117 Mp-17-01 oliv3 38.75 0.017 0.281 18.69 0.098 0.005 41.68 0.009 0.003 Mp-17-01 oliv3 36.56 0.232 0.518 28.32 0.075 0.000 36.33 0.002 0.117 Mp-17-01 oliv3 36.49 0.027 0.486 26.72 0.045 0.001 35.08 0.010 0.022 Mp-17-01 oliv4 38.49 0.026 0.234 15.79 0.128 0.001 44.10 0.007 0.009 Mp-17-01 oliv4 38.62 0.024 0.276 17.37 0.069 0.001 42.88 0.011 0.006 Mp-17-01 oliv4 37.49 0.022 0.407 23.43 0.055 0.011 37.86 0.006 0.013 MP-17-02_oliv1 38.96 0.034 0.262 16.57 0.155 0.000 43.54 0.012 0.009 MP-17-02_oliv1 39.02 0.017 0.231 15.96 0.175 0.000 44.00 0.007 0.000 MP-17-02_oliv1 37.82 0.031 0.394 22.46 0.058 0.002 38.50 0.005 0.002 MP-17-02_oliv1 37.06 0.018 0.484 24.96 0.067 0.000 36.38 0.006 0.001 MP-17-02_oliv2 38.46 0.018 0.270 17.22 0.147 0.002 42.79 0.010 0.006 MP-17-02_oliv2 38.38 0.030 0.283 16.60 0.133 0.004 43.06 0.013 0.001 MP-17-02_oliv2 35.88 0.016 0.628 30.46 0.019 0.004 32.23 0.001 0.030 MP-17-02_oliv2 36.77 0.016 0.401 24.01 0.118 0.004 36.95 0.100 0.050 MP-17-02_oliv3 37.84 0.031 0.283 18.27 0.121 0.005 42.07 0.013 0.005 MP-17-02_oliv3 38.64 0.026 0.249 16.91 0.098 0.002 43.18 0.011 0.008 MP-17-02_oliv3 36.61 0.024 0.527 27.80 0.054 0.006 33.97 0.005 0.012 MP-17-02_oliv3 51.15 0.983 0.622 18.14 0.028 0.155 20.34 0.015 0.531 MP-17-02_oliv3 37.59 0.023 0.410 22.92 0.096 0.005 38.25 0.202 0.026 MP-17-02_oliv4 38.82 0.030 0.273 17.24 0.110 0.000 42.80 0.013 0.007 MP-17-02_oliv4 37.11 0.026 0.443 24.11 0.064 0.000 37.11 0.005 0.009 MP-17-02_oliv4 36.34 0.015 0.531 26.80 0.063 0.000 34.92 0.010 0.010 MP-17-02_oliv6 52.60 0.942 0.498 15.10 0.027 0.032 26.91 0.017 0.375 MP-17-02_oliv6 51.96 2.150 0.352 13.81 0.015 0.053 27.05 0.047 0.365 MP-17-02_oliv6 50.34 1.670 0.370 11.03 0.007 0.358 16.31 0.002 0.613 Mp-17-25 oliv1 35.57 0.023 0.560 32.96 0.020 0.006 29.69 0.000 0.018 Mp-17-25 oliv2 35.33 0.019 0.549 32.92 0.041 0.000 29.78 0.010 0.029 Mp-17-25 oliv3 37.29 0.037 0.407 26.29 0.059 0.005 35.57 0.000 0.016 Mp-17-25 oliv3 36.32 0.026 0.535 31.27 0.067 0.000 31.41 0.000 0.016 Mp-17-25 oliv4 36.17 0.023 0.489 28.86 0.067 0.009 33.44 0.010 0.022 Mp-17-25 oliv4 35.61 0.022 0.552 32.91 0.049 0.000 30.34 0.000 0.023 MP-17-29_oliv1 36.32 0.024 0.540 28.90 0.066 0.000 33.36 0.003 0.016 MP-17-29_oliv1 36.66 0.025 0.507 27.84 0.069 0.007 34.25 0.012 0.014 MP-17-29_oliv3 37.38 0.017 0.411 22.79 0.106 0.006 38.00 0.008 0.001 MP-17-29_oliv3 36.85 0.047 0.486 27.02 0.098 0.006 33.20 0.002 0.010 MP-17-29_oliv4 35.97 0.051 0.517 28.32 0.067 0.004 33.62 0.000 0.015 MP-17-29_oliv4 36.66 0.019 0.503 28.36 0.060 0.002 33.89 0.015 0.015 MP-17-29_oliv4 36.53 0.019 0.502 28.16 0.077 0.007 34.12 0.039 0.113 MP-17-29_oliv4 35.89 0.006 0.556 29.48 0.086 0.002 33.20 0.001 0.024 74

Sample SiO2 Al2O3 MnO FeO NiO Na2O MgO Cr2O3 TiO2 Mp-17-33 oliv1 38.17 0.033 0.296 19.18 0.120 0.006 41.11 0.013 0.012 Mp-17-33 oliv1 37.99 0.024 0.306 19.18 0.127 0.008 41.09 0.002 0.007 Mp-17-33 oliv1 37.28 0.016 0.381 22.97 0.096 0.006 38.01 0.009 0.011 Mp-17-33 oliv1 37.04 0.025 0.465 25.44 0.081 0.000 36.08 0.000 0.010 Mp-17-33 oliv11 37.84 0.029 0.319 20.08 0.106 0.000 40.40 0.004 0.014 Mp-17-33 oliv11 37.55 0.014 0.402 22.82 0.107 0.008 38.49 0.006 0.013 Mp-17-33 oliv12 38.10 0.026 0.294 19.42 0.110 0.008 40.87 0.007 0.009 Mp-17-33 oliv12 37.83 0.029 0.329 19.21 0.097 0.012 40.89 0.045 0.004 Mp-17-33 oliv12 36.83 0.034 0.438 25.28 0.067 0.008 35.97 0.005 0.011 Mp-17-33 oliv5 37.28 0.034 0.388 24.44 0.105 0.000 36.95 0.005 0.009 Mp-17-33 oliv7 37.88 0.024 0.413 22.73 0.112 0.009 38.18 0.009 0.005 Mp-17-33 oliv7 37.42 0.028 0.377 21.53 0.109 0.005 39.13 0.000 0.006 Mp-17-33 oliv7 36.57 0.020 0.402 24.28 0.081 0.000 36.98 0.007 0.012 Mp-17-33 oliv7 37.06 0.023 0.433 24.51 0.063 0.000 36.72 0.027 0.018 Mp-17-36 oliv11 38.01 0.038 0.373 20.67 0.091 0.000 40.01 0.018 0.011 Mp-17-36 oliv11 37.58 0.028 0.449 23.67 0.025 0.000 37.39 0.000 0.010 Mp-17-36 oliv11 37.66 0.026 0.395 23.57 0.059 0.000 37.59 0.088 0.098 Mp-17-36 oliv12 38.30 0.023 0.330 18.19 0.220 0.000 41.72 0.015 0.007 Mp-17-36 oliv12 38.52 0.027 0.304 18.94 0.064 0.000 41.18 0.018 0.005 Mp-17-36 oliv12 38.35 0.022 0.304 20.05 0.105 0.002 41.02 0.007 0.010 Mp-17-36 oliv13 38.08 0.028 0.315 18.76 0.099 0.000 41.55 0.011 0.000 Mp-17-36 oliv13 37.46 0.023 0.354 19.96 0.085 0.004 40.36 0.007 0.019 Mp-17-36 oliv13 38.29 0.033 0.368 19.46 0.100 0.004 40.75 0.014 0.012 Mp-17-36 oliv13 37.40 0.022 0.357 20.64 0.067 0.006 39.77 0.038 0.029 Mp-17-36 oliv14 37.86 0.026 0.325 20.09 0.148 0.010 40.40 0.012 0.002 Mp-17-36 oliv14 37.88 0.025 0.329 19.60 0.188 0.006 40.96 0.009 0.004 Mp-17-36 oliv14 36.86 0.164 0.388 22.26 0.104 0.010 38.14 0.239 0.091 Mp-17-36 oliv14 38.21 0.021 0.363 21.69 0.130 0.003 39.20 0.057 0.017 75

Sample CaO Total Mp-17-01 oliv1 0.113 99.87 Mp-17-01 oliv1 0.232 100.19 Mp-17-01 oliv1 0.153 99.53 Mp-17-01 oliv2 0.191 99.15 Mp-17-01 oliv2 7.210 98.28 Mp-17-01 oliv3 0.144 99.68 Mp-17-01 oliv3 0.358 102.51 Mp-17-01 oliv3 4.221 103.10 Mp-17-01 oliv4 3.701 102.49 Mp-17-01 oliv4 0.221 99.48 Mp-17-01 oliv4 0.283 99.57 MP-17-02_oliv1 1.463 101.00 MP-17-02_oliv1 0.118 99.53 MP-17-02_oliv1 0.139 99.42 MP-17-02_oliv1 0.161 99.13 MP-17-02_oliv2 1.767 100.69 MP-17-02_oliv2 4.193 102.69 MP-17-02_oliv2 0.182 99.44 MP-17-02_oliv2 0.173 98.59 MP-17-02_oliv3 5.107 103.75 MP-17-02_oliv3 0.160 99.28 MP-17-02_oliv3 1.865 100.87 MP-17-02_oliv3 6.353 98.32 MP-17-02_oliv3 0.304 99.82 MP-17-02_oliv4 0.143 99.44 MP-17-02_oliv4 0.250 99.13 MP-17-02_oliv4 0.264 98.95 MP-17-02_oliv6 6.665 103.17 MP-17-02_oliv6 7.785 103.59 MP-17-02_oliv6 15.942 96.64 Mp-17-25 oliv1 2.373 101.22 Mp-17-25 oliv2 1.981 100.66 Mp-17-25 oliv3 0.291 99.97 Mp-17-25 oliv3 1.734 101.37 Mp-17-25 oliv4 5.426 104.52 Mp-17-25 oliv4 1.345 100.85 MP-17-29_oliv1 0.152 99.37 MP-17-29_oliv1 0.191 99.58 MP-17-29_oliv3 1.850 100.56 MP-17-29_oliv3 0.162 97.88 MP-17-29_oliv4 6.492 105.06 MP-17-29_oliv4 0.152 99.68 MP-17-29_oliv4 0.100 99.66 MP-17-29_oliv4 2.155 101.40 76

Sample CaO Total Mp-17-33 oliv1 0.137 99.07 Mp-17-33 oliv1 0.152 98.89 Mp-17-33 oliv1 2.981 101.76 Mp-17-33 oliv1 3.080 102.22 Mp-17-33 oliv11 2.974 101.77 Mp-17-33 oliv11 0.301 99.71 Mp-17-33 oliv12 0.140 98.99 Mp-17-33 oliv12 0.241 98.68 Mp-17-33 oliv12 1.228 99.87 Mp-17-33 oliv5 0.252 99.46 Mp-17-33 oliv7 0.148 99.51 Mp-17-33 oliv7 2.119 100.73 Mp-17-33 oliv7 5.532 103.88 Mp-17-33 oliv7 0.372 99.22 Mp-17-36 oliv11 1.910 101.14 Mp-17-36 oliv11 0.578 99.73 Mp-17-36 oliv11 0.269 99.75 Mp-17-36 oliv12 0.107 98.91 Mp-17-36 oliv12 0.134 99.18 Mp-17-36 oliv12 0.256 100.12 Mp-17-36 oliv13 0.826 99.67 Mp-17-36 oliv13 4.618 102.89 Mp-17-36 oliv13 0.147 99.18 Mp-17-36 oliv13 3.993 102.32 Mp-17-36 oliv14 0.133 99.01 Mp-17-36 oliv14 1.281 100.28 Mp-17-36 oliv14 2.495 100.75 Mp-17-36 oliv14 0.142 99.83 77

Table A3. Oregon State University electron microprobe pyroxene data in oxide weight% from samples: MP-17-01, 02, 25, 29, 33, 36.

Sample SiO2 Al2O3 K2O FeO Na2O MgO TiO2 CaO Mp-17-01 cpx1 52.29 3.79 0.003 6.34 0.305 17.154 0.304 19.24 Mp-17-01 cpx1 51.58 4.94 0.008 6.63 0.298 16.271 0.380 19.47 Mp-17-01 cpx1 51.24 4.83 0.001 6.50 0.310 16.335 0.379 19.64 Mp-17-01 cpx6 52.66 2.35 0.004 8.27 0.331 16.878 0.414 19.07 Mp-17-01 cpx6 51.93 4.05 0.010 6.36 0.301 16.749 0.342 19.47 Mp-17-01 cpx6 52.70 3.54 0.003 6.29 0.274 17.498 0.272 19.33 Mp-17-01 cpx7 52.02 2.72 0.000 7.18 0.235 17.606 0.326 18.56 Mp-17-01 cpx7 50.84 4.59 0.018 9.36 0.294 16.240 0.620 18.14 Mp-17-01 cpx7 52.38 2.86 0.000 8.73 0.263 17.040 0.389 18.41 MP-17-02_pyx_oliv1 52.39 2.12 0.000 11.87 0.290 18.173 0.464 15.25 MP-17-02_pyx_oliv1 53.02 1.70 0.000 12.16 0.328 17.346 0.469 15.87 MP-17-02_pyx_oliv1 54.82 0.85 0.028 17.88 0.049 27.648 0.229 1.95 MP-17-02_pyx_oliv1 51.54 1.77 0.000 13.13 0.387 15.779 0.726 16.35 MP-17-02_pyx_oliv6 52.55 1.93 0.000 10.72 0.370 17.147 0.640 16.85 Mp-17-25 cpx1 52.35 2.16 0.000 12.51 0.379 15.708 0.553 16.88 Mp-17-25 cpx3 54.45 1.15 0.010 19.76 0.045 26.292 0.321 1.92 Mp-17-25 cpx3 54.89 1.23 0.003 19.25 0.045 26.375 0.285 2.01 Mp-17-25 cpx3 54.46 1.54 0.000 18.87 0.046 26.072 0.291 2.00 Mp-17-25 cpx5 52.16 2.04 0.016 11.99 0.337 15.971 0.611 16.96 Mp-17-25 cpx5 52.00 2.07 0.000 12.12 0.341 16.119 0.611 16.87 Mp-17-25 cpx5 52.45 2.24 0.000 11.44 0.316 16.712 0.537 16.52 MP-17-29_pyx_oliv1 51.55 3.49 0.006 8.01 0.307 16.108 0.481 19.55 MP-17-29_pyx_oliv1 51.32 3.58 0.000 8.82 0.320 15.650 0.494 19.37 MP-17-29_pyx_oliv1 53.78 1.07 0.000 20.64 0.048 25.498 0.405 2.13 MP-17-29_pyx_oliv4 53.70 0.85 0.006 21.28 0.050 25.633 0.422 1.67 MP-17-29_pyx_oliv4 54.04 0.86 0.000 20.20 0.043 26.047 0.365 1.81 MP-17-29_pyx1 50.99 4.24 0.000 9.10 0.357 15.762 0.673 18.98 MP-17-29_pyx1 50.11 4.60 0.000 9.28 0.350 15.274 0.679 18.24 Mp-17-33 cpx1 51.21 3.77 0.011 10.07 0.362 15.996 0.618 18.06 Mp-17-33 cpx1 52.83 2.16 0.006 9.47 0.392 16.087 0.447 18.95 Mp-17-33 cpx1 52.92 1.99 0.000 9.40 0.368 16.163 0.471 18.95 Mp-17-33 cpx2 56.19 27.84 0.376 1.79 5.268 0.086 0.082 9.55 Mp-17-33 cpx3 53.50 5.91 0.068 11.50 1.190 15.126 0.368 14.44 Mp-17-33 cpx3 54.17 5.64 0.085 19.25 1.118 18.635 0.259 4.08 Mp-17-33 cpx4 53.98 0.68 0.000 21.19 0.076 23.893 0.346 2.99 Mp-17-36 cpx1 52.09 2.01 0.011 10.98 0.359 16.553 0.635 17.29 Mp-17-36 cpx1 52.58 2.08 0.002 10.10 0.319 17.600 0.453 16.75 Mp-17-36 cpx1 53.01 2.03 0.007 10.37 0.302 17.815 0.461 16.18 Mp-17-36 cpx2 51.40 2.64 0.006 13.78 0.320 17.061 0.756 14.48 78

Sample MnO Cr2O3 Total Mp-17-01 cpx1 0.170 0.454 100.05 Mp-17-01 cpx1 0.140 0.687 100.40 Mp-17-01 cpx1 0.140 0.648 100.02 Mp-17-01 cpx6 0.217 0.005 100.19 Mp-17-01 cpx6 0.125 0.519 99.86 Mp-17-01 cpx6 0.184 0.356 100.45 Mp-17-01 cpx7 0.164 0.334 99.14 Mp-17-01 cpx7 0.189 0.185 100.47 Mp-17-01 cpx7 0.207 0.079 100.35 MP-17-02_pyx_oliv1 0.361 0.025 100.94 MP-17-02_pyx_oliv1 0.373 0.031 101.29 MP-17-02_pyx_oliv1 0.451 0.006 103.92 MP-17-02_pyx_oliv1 0.409 0.022 100.11 MP-17-02_pyx_oliv6 0.340 0.008 100.55 Mp-17-25 cpx1 0.304 0.012 100.85 Mp-17-25 cpx3 0.431 0.035 104.40 Mp-17-25 cpx3 0.401 0.050 104.53 Mp-17-25 cpx3 0.388 0.045 103.72 Mp-17-25 cpx5 0.304 0.007 100.40 Mp-17-25 cpx5 0.288 0.000 100.43 Mp-17-25 cpx5 0.268 0.134 100.63 MP-17-29_pyx_oliv1 0.177 0.319 100.00 MP-17-29_pyx_oliv1 0.143 0.372 100.06 MP-17-29_pyx_oliv1 0.443 0.000 104.02 MP-17-29_pyx_oliv4 0.552 0.012 104.18 MP-17-29_pyx_oliv4 0.504 0.004 103.87 MP-17-29_pyx1 0.209 0.253 100.56 MP-17-29_pyx1 0.179 0.147 98.85 Mp-17-33 cpx1 0.256 0.156 100.50 Mp-17-33 cpx1 0.278 0.016 100.63 Mp-17-33 cpx1 0.333 0.061 100.66 Mp-17-33 cpx2 0.014 0.011 101.21 Mp-17-33 cpx3 0.344 0.011 102.47 Mp-17-33 cpx3 0.558 0.000 103.80 Mp-17-33 cpx4 0.559 0.013 103.73 Mp-17-36 cpx1 0.293 0.028 100.24 Mp-17-36 cpx1 0.287 0.092 100.25 Mp-17-36 cpx1 0.292 0.074 100.54 Mp-17-36 cpx2 0.395 0.015 100.86 79

Table A4. Oregon State University electron microprobe plagioclase data in oxide weight% from samples: MP-17-01, 02, 08, 25, 29, 33, 36.

Sample Na2O MgO SiO2 Al2O3 FeO CaO K2O SrO Total MP-17-01 plag1 2.871 0.148 50.24 31.34 0.821 14.52 0.118 0.163 100.22 MP-17-01 plag1 1.992 0.129 48.22 33.18 0.656 16.51 0.056 0.112 100.86 MP-17-01 plag2 2.269 0.143 48.75 32.55 0.730 15.80 0.073 0.167 100.48 MP-17-01 plag2 3.153 0.170 50.94 30.80 1.024 14.08 0.126 0.151 100.44 MP-17-01 plag2 1.243 0.088 46.00 34.38 0.733 17.73 0.048 0.109 100.33 MP-17-01 plag3 2.017 0.336 48.15 32.78 0.876 16.14 0.070 0.149 100.51 MP-17-01 plag4 1.649 0.108 47.45 33.84 0.640 17.14 0.050 0.105 100.99 MP-17-01 plag4 2.471 0.162 48.95 32.28 0.755 15.51 0.099 0.097 100.33 MP-17-01 plag4 1.391 0.057 46.40 34.48 0.633 17.57 0.047 0.111 100.69 MP-17-01 plag5 3.374 0.093 51.10 31.24 0.533 13.77 0.132 0.174 100.41 MP-17-01 plag5 2.332 0.077 48.79 32.73 0.714 15.68 0.112 0.146 100.58 MP-17-01 plag5 2.678 0.134 50.11 31.96 0.849 15.14 0.106 0.190 101.16 MP-17-01 plag5 3.337 0.100 51.21 30.70 1.093 13.67 0.194 0.164 100.46 MP-17-01 plag6 3.118 0.316 71.15 12.01 3.451 0.92 5.199 0.000 96.16 MP-17-01 plag6 1.352 0.088 46.63 34.61 0.627 17.62 0.038 0.143 101.10 MP-17-01 plag7 1.472 0.080 46.70 34.31 0.679 17.28 0.055 0.151 100.73 MP-17-01 plag7 2.748 0.167 49.22 31.78 0.698 14.91 0.089 0.139 99.75 MP-17-01 plag7 2.305 0.147 49.17 32.61 0.736 15.62 0.073 0.168 100.82 MP-17-01 plag7 2.342 0.146 48.61 32.60 0.686 15.64 0.065 0.136 100.22 MP-17-01 plag8 2.683 0.138 50.07 31.80 0.796 14.76 0.105 0.181 100.53 MP-17-01 plag8 4.799 0.103 54.94 28.11 1.253 10.77 0.380 0.140 100.50 MP-17-01 plag8 4.030 0.121 53.01 29.75 0.704 12.36 0.315 0.065 100.36 MP-17-02 plag1 1.253 0.051 45.73 34.74 0.660 17.91 0.056 0.098 100.50 MP-17-02 plag1 1.470 0.074 46.67 34.33 0.684 17.63 0.062 0.146 101.07 MP-17-02 plag1 4.791 0.097 54.86 28.03 1.293 10.91 0.332 0.143 100.45 MP-17-02 plag1 2.783 0.051 49.69 31.92 0.982 14.74 0.138 0.169 100.48 MP-17-02 plag2 1.568 0.108 47.04 34.16 0.574 17.06 0.040 0.124 100.68 MP-17-02 plag2 3.327 0.097 51.24 30.99 0.964 13.70 0.193 0.176 100.68 MP-17-02 plag2 1.617 0.112 47.27 33.96 0.592 17.11 0.049 0.140 100.84 MP-17-02 plag3 2.844 0.028 49.26 32.45 0.891 15.10 0.152 0.155 100.88 MP-17-02 plag3 6.569 0.018 66.33 19.75 0.825 1.80 3.779 0.051 99.11 MP-17-02 plag3 1.668 0.087 46.52 34.41 0.664 17.11 0.035 0.093 100.59 MP-17-02 plag3 4.828 0.074 54.78 27.92 1.231 10.63 0.359 0.161 99.97 MP-17-02 plag4 2.523 0.045 49.32 32.36 0.929 15.28 0.106 0.153 100.71 MP-17-02 plag4 3.707 0.069 51.75 29.90 1.309 12.88 0.200 0.190 100.01 MP-17-02 plag4 4.626 0.081 54.18 28.38 1.241 11.05 0.334 0.168 100.06 MP-17-02 plag5 1.529 0.105 47.16 34.15 0.569 17.12 0.034 0.143 100.81 MP-17-02 plag5 3.461 0.096 51.34 30.42 1.137 13.27 0.192 0.151 100.06 MP-17-02 plag5 2.543 0.070 49.12 32.22 0.817 15.28 0.112 0.127 100.29 MP-17-02 plag6 2.328 0.050 48.76 32.65 0.774 15.77 0.128 0.150 100.61 MP-17-02 plag6 2.628 0.102 49.04 32.38 0.733 15.20 0.097 0.163 100.35 MP-17-08 plag1 5.518 0.054 56.23 27.16 0.494 9.12 0.338 0.144 99.05 MP-17-08 plag1 5.208 0.062 55.30 27.84 0.602 10.01 0.294 0.137 99.46 MP-17-08 plag2 5.260 0.062 55.60 27.76 0.514 9.71 0.319 0.133 99.37 80

Sample Na2O MgO SiO2 Al2O3 FeO CaO K2O SrO Total MP-17-08 plag2 4.876 0.064 55.40 28.25 0.567 10.90 0.285 0.171 100.52 MP-17-08 plag2 4.778 0.067 54.32 28.40 0.509 10.63 0.264 0.133 99.11 MP-17-08 plag3 5.275 0.054 55.92 27.90 0.537 10.12 0.313 0.140 100.25 MP-17-08 plag3 5.026 0.063 55.75 28.09 0.676 10.30 0.294 0.156 100.36 MP-17-08 plag3 5.050 0.065 55.43 28.06 0.544 10.13 0.268 0.199 99.75 MP-17-08 plag4 4.853 0.068 54.26 28.38 0.521 10.64 0.261 0.145 99.13 MP-17-08 plag4 5.070 0.060 55.88 28.00 0.495 10.22 0.282 0.130 100.14 MP-17-08 plag5 5.184 0.060 56.08 27.99 0.487 9.93 0.300 0.161 100.19 MP-17-08 plag5 4.938 0.066 55.37 28.46 0.585 10.44 0.272 0.157 100.28 MP-17-08 plag5 5.369 0.058 55.79 27.87 0.485 9.74 0.300 0.176 99.79 MP-17-08 plag6 5.804 0.044 57.71 26.56 0.418 8.50 0.415 0.157 99.61 MP-17-08 plag6 5.252 0.055 56.37 27.83 0.484 9.83 0.304 0.144 100.27 MP-17-08 plag6 5.682 0.047 56.51 26.98 0.426 9.06 0.370 0.175 99.25 MP-17-25 plag 1 1.998 0.074 48.27 33.20 0.637 16.25 0.101 0.094 100.62 MP-17-25 plag 1 4.055 0.108 53.29 29.70 0.697 12.32 0.280 0.101 100.55 MP-17-25 plag 1 4.478 0.102 54.82 28.45 0.794 11.16 0.350 0.101 100.25 MP-17-25 plag 1 2.075 0.075 47.99 33.10 0.691 16.03 0.136 0.101 100.20 MP-17-25 plag 2 4.132 0.108 53.44 29.42 0.719 12.09 0.304 0.131 100.36 MP-17-25 plag 2 4.442 0.115 54.29 28.90 0.698 11.64 0.336 0.082 100.51 MP-17-25 plag 2 4.570 0.102 54.39 29.00 0.741 11.42 0.328 0.102 100.66 MP-17-25 plag 2 4.277 0.099 53.63 29.19 0.872 11.66 0.294 0.129 100.15 MP-17-25 plag 3 4.001 0.097 52.97 29.73 0.730 12.26 0.273 0.081 100.14 MP-17-25 plag 3 3.769 0.077 52.52 30.15 0.824 12.97 0.270 0.100 100.68 MP-17-25 plag 3 3.759 0.114 52.84 30.08 0.649 12.82 0.260 0.098 100.62 MP-17-25 plag 4 3.879 0.120 53.13 30.05 0.702 12.64 0.257 0.092 100.88 MP-17-25 plag 4 4.922 0.096 55.54 28.01 0.801 10.43 0.401 0.061 100.27 MP-17-25 plag 5 3.833 0.079 53.33 29.94 0.839 12.65 0.316 0.109 101.09 MP-17-25 plag 5 4.691 0.092 53.91 28.44 1.145 11.06 0.304 0.121 99.76 MP-17-25 plag 5 3.823 0.067 52.63 30.20 0.728 12.78 0.264 0.122 100.61 MP-17-25 plag 5 3.894 0.077 53.04 29.75 0.895 12.44 0.273 0.108 100.48 MP-17-25 plag 5 4.724 0.102 54.92 28.49 0.947 10.97 0.401 0.068 100.63 MP-17-25 plag 5 4.987 0.120 55.49 27.94 0.738 10.32 0.407 0.091 100.09 MP-17-25 plag 6 4.517 0.105 54.50 28.55 0.770 11.18 0.364 0.123 100.11 MP-17-25 plag 6 2.121 0.059 48.20 32.97 0.618 15.99 0.078 0.175 100.21 MP-17-29 plag1 1.206 0.036 45.59 34.72 0.534 17.77 0.023 0.138 100.01 MP-17-29 plag1 1.831 0.039 47.38 33.57 0.661 16.75 0.058 0.172 100.45 MP-17-29 plag1 1.715 0.020 47.35 33.88 0.640 16.90 0.085 0.133 100.72 MP-17-29 plag2 1.586 0.045 46.94 33.86 0.634 17.19 0.059 0.154 100.47 MP-17-29 plag2 1.867 0.016 47.85 33.81 0.737 16.73 0.093 0.122 101.23 MP-17-29 plag2 1.784 0.037 47.46 33.86 0.661 16.87 0.073 0.170 100.91 MP-17-29 plag2 1.997 0.038 47.76 33.40 0.674 16.54 0.092 0.135 100.63 MP-17-29 plag3 1.961 0.044 48.43 33.10 0.897 16.39 0.095 0.137 101.06 MP-17-29 plag3 2.498 0.053 48.92 32.39 0.866 15.60 0.146 0.117 100.58 MP-17-29 plag3 2.792 0.035 49.15 31.88 0.856 14.96 0.154 0.146 99.97 MP-17-29 plag4 1.508 0.042 46.61 34.09 0.570 17.55 0.035 0.153 100.55 MP-17-29 plag4 1.276 0.030 46.47 34.60 0.618 17.82 0.052 0.176 101.04 MP-17-29 plag4 4.605 0.055 54.06 28.64 1.012 11.11 0.402 0.153 100.04 81

Sample Na2O MgO SiO2 Al2O3 FeO CaO K2O SrO Total MP-17-29 plag4 2.303 0.043 48.18 32.99 0.669 15.80 0.093 0.147 100.23 MP-17-29 plag4 2.477 0.018 48.40 32.50 0.824 15.32 0.140 0.135 99.82 MP-17-33 plag 11 1.477 0.065 46.40 34.31 0.591 17.27 0.034 0.152 100.30 MP-17-33 plag 11 1.673 0.073 46.92 33.73 0.625 16.82 0.045 0.149 100.03 MP-17-33 plag 11 1.853 0.060 47.16 33.51 0.852 16.50 0.074 0.194 100.20 MP-17-33 plag 11 1.472 0.073 47.09 33.91 0.550 17.45 0.040 0.129 100.72 MP-17-33 plag 12 3.373 0.531 50.68 27.11 2.443 13.07 1.122 0.108 98.44 MP-17-33 plag 12 1.808 0.062 47.20 33.48 0.826 16.74 0.064 0.153 100.33 MP-17-33 plag 12 1.667 0.079 46.82 33.74 0.579 16.94 0.051 0.143 100.02 MP-17-33 plag 2 2.224 0.091 48.83 32.77 0.655 15.66 0.084 0.184 100.50 MP-17-33 plag 2 2.333 0.087 48.51 32.60 0.760 15.44 0.089 0.136 99.96 MP-17-33 plag 2 2.357 0.094 48.99 32.34 0.746 15.53 0.094 0.139 100.29 MP-17-33 plag 2 2.183 0.083 48.32 32.78 0.741 15.83 0.071 0.144 100.15 MP-17-33 plag 2 1.970 0.057 47.05 33.26 0.723 16.53 0.070 0.115 99.77 MP-17-33 plag 2 1.444 0.210 46.28 33.35 0.841 17.00 0.060 0.130 99.31 MP-17-33 plag 4 1.625 0.071 46.89 33.87 0.709 17.02 0.047 0.132 100.36 MP-17-33 plag 4 2.368 0.093 48.52 32.77 0.693 15.90 0.069 0.144 100.56 MP-17-33 plag 4 2.706 0.103 49.74 31.96 0.635 15.14 0.106 0.160 100.55 MP-17-33 plag 4 4.921 0.061 55.12 27.51 1.169 10.50 0.506 0.175 99.97 MP-17-33 plag 4 1.838 0.074 47.62 33.68 0.573 16.81 0.058 0.134 100.78 MP-17-33 plag 5 2.082 0.093 47.87 33.11 0.738 16.29 0.051 0.150 100.39 MP-17-33 plag 5 1.504 0.066 46.50 34.28 0.621 17.28 0.034 0.136 100.42 MP-17-33 plag 8 1.462 0.061 46.70 34.19 0.606 17.38 0.056 0.151 100.61 MP-17-33 plag 8 1.570 0.066 46.87 34.02 0.638 17.15 0.054 0.152 100.52 MP-17-33 plag 8 1.459 0.072 45.84 34.31 0.634 17.50 0.034 0.127 99.97 MP-17-36 plag 1 1.484 0.063 46.58 34.47 0.629 17.49 0.036 0.131 100.89 MP-17-36 plag 1 1.576 0.057 46.73 33.70 0.768 17.20 0.053 0.157 100.24 MP-17-36 plag 2 3.529 0.137 51.19 30.27 0.834 13.30 0.141 0.186 99.59 MP-17-36 plag 2 3.834 0.135 51.89 30.07 0.901 12.93 0.146 0.170 100.08 MP-17-36 plag 2 1.714 0.083 47.17 33.86 0.663 16.70 0.031 0.163 100.39 MP-17-36 plag 2 1.722 0.081 47.51 33.36 0.721 16.87 0.048 0.141 100.45 MP-17-36 plag 2 3.211 0.122 50.62 30.97 0.955 13.95 0.122 0.141 100.09 MP-17-36 plag 2 4.165 0.142 53.10 29.11 1.252 12.11 0.213 0.182 100.28 MP-17-36 plag 2 4.627 0.117 54.19 28.87 1.036 11.15 0.268 0.139 100.40 MP-17-36 plag 2 3.935 0.131 53.10 29.50 1.131 12.19 0.204 0.138 100.34 MP-17-36 plag 2 4.351 0.124 53.31 28.95 1.036 11.82 0.209 0.181 99.99 MP-17-36 plag 4 3.940 0.148 53.27 29.43 0.931 12.24 0.155 0.150 100.25 MP-17-36 plag 4 3.472 0.139 51.29 30.36 0.837 13.54 0.127 0.169 99.93 MP-17-36 plag 4 1.401 0.071 46.57 34.44 0.585 17.67 0.026 0.142 100.91 MP-17-36 plag 5 1.599 0.077 46.61 34.13 0.632 17.25 0.041 0.125 100.47 MP-17-36 plag 5 1.372 0.070 46.20 34.28 0.719 17.40 0.029 0.143 100.22 MP-17-36 plag 5 1.455 0.070 46.23 34.31 0.678 17.30 0.037 0.164 100.25 MP-17-36 plag 5 1.518 0.057 46.41 34.21 0.698 17.31 0.055 0.127 100.39 MP-17-36 plag 5 2.069 0.083 48.48 33.21 0.594 16.00 0.066 0.124 100.63 MP-17-36 plag 5 1.691 0.076 46.98 33.79 0.572 16.90 0.034 0.169 100.22 MP-17-36 plag 6 3.561 0.128 52.17 30.16 0.843 13.49 0.132 0.136 100.63 MP-17-36 plag 6 3.638 0.137 52.11 30.22 0.926 13.22 0.133 0.160 100.54 82

Sample Na2O MgO SiO2 Al2O3 FeO CaO K2O SrO Total MP-17-36 plag 6 3.774 0.156 51.73 29.90 0.952 13.19 0.157 0.169 100.04 MP-17-36 plag 6 2.172 0.086 47.98 33.36 0.558 16.22 0.053 0.142 100.56 83

Table A5. WUSTL electron microprobe data for olivine phenocrysts within the following samples: MP-17-01, 02, 04, 09, 25, 29, 33, 36. Detection limit was analyzed at 99% confidence level (3σ) (b.d.l.=below detection limit).

Sample Na2O MgO Al2O3 SiO2 TiO2 V2O3 FeO P2O5 CaO Cr2O3 01 oliv_5 b.d.l. 43.227 b.d.l. 39.684 0.013 0 16.716 0.008 0.168 0.010 01 oliv_5 b.d.l. 37.719 b.d.l. 38.387 0.014 0 23.392 b.d.l. 0.193 0.006 01 oliv-5 b.d.l. 43.260 b.d.l. 39.557 b.d.l. 0 16.836 0.010 0.177 0.011 01 oliv-6 b.d.l. 43.585 b.d.l. 39.787 b.d.l. 0 16.327 0.008 0.123 0.012 01 oliv-6 b.d.l. 43.384 b.d.l. 39.471 b.d.l. 0 16.797 0.012 0.123 0.020 01 oliv-6 b.d.l. 43.628 b.d.l. 39.399 0.012 0 16.671 0.009 b.d.l. 0.001 01 oliv-6 b.d.l. 35.098 b.d.l. 37.863 0.017 0 26.060 0.017 0.210 0.012 01 oliv-6 b.d.l. 38.008 b.d.l. 38.145 0.013 0 23.263 0.011 b.d.l. -0.002 01 oliv-7 b.d.l. 43.242 b.d.l. 39.199 b.d.l. 0 16.936 b.d.l. 0.129 0.022 01 oliv-7 b.d.l. 43.133 b.d.l. 39.406 b.d.l. 0 16.965 b.d.l. 0.125 0.015 01 oliv-7 b.d.l. 43.563 b.d.l. 39.759 b.d.l. 0 16.344 0.016 0.128 0.063 01 oliv-7 b.d.l. 38.550 b.d.l. 38.666 0.024 0 22.213 b.d.l. 0.192 0.011 01 oliv-7 b.d.l. 35.892 b.d.l. 37.763 b.d.l. 0 25.506 0.010 b.d.l. -0.001 01 oliv-7 b.d.l. 43.255 b.d.l. 39.551 b.d.l. 0 16.664 b.d.l. 0.127 0.034 01 oliv-8 b.d.l. 44.042 b.d.l. 39.461 b.d.l. 0 15.891 0.018 0.166 0.018 01 oliv-8 b.d.l. 36.452 b.d.l. 37.726 0.015 0 24.836 0.009 b.d.l. 0.004 01 oliv-9 b.d.l. 34.366 b.d.l. 37.511 b.d.l. 0 27.239 0.009 b.d.l. -0.003 01 oliv-9 b.d.l. 43.636 b.d.l. 39.468 b.d.l. 0 16.323 b.d.l. b.d.l. 0.002 01 oliv-10 b.d.l. 41.020 b.d.l. 38.674 0.018 0 19.391 0.020 0.154 0.011 01 oliv-10 b.d.l. 35.683 b.d.l. 37.729 b.d.l. 0 25.350 b.d.l. 0.217 0.006 01 oliv-11 b.d.l. 36.563 b.d.l. 37.778 0.013 0 24.870 b.d.l. 0.196 0.012 01 oliv-11 b.d.l. 45.326 b.d.l. 39.895 b.d.l. 0 14.232 b.d.l. 0.132 0.019 02 oliv 1 b.d.l. 44.024 b.d.l. 39.010 0.018 0 16.346 0.035 0.121 0.006 02 oliv 1 b.d.l. 36.788 b.d.l. 37.671 b.d.l. 0 24.925 b.d.l. b.d.l. 0.001 02 oliv 2 b.d.l. 43.184 b.d.l. 39.275 b.d.l. 0 17.463 b.d.l. 0.129 0.009 02 oliv 2 b.d.l. 42.105 b.d.l. 38.988 0.012 0 18.559 0.013 0.149 0.014 02 oliv 2 b.d.l. 34.367 b.d.l. 37.126 0.014 0 27.532 0.011 b.d.l. 0.002 02 oliv 3 b.d.l. 43.537 b.d.l. 39.422 0.018 0 17.029 b.d.l. 0.119 0.017 02 oliv 3 b.d.l. 31.545 b.d.l. 36.730 0.013 0 30.862 0.010 b.d.l. 0.001 02 oliv 4 b.d.l. 43.389 b.d.l. 39.533 b.d.l. 0 17.104 0.012 0.145 0.009 02 oliv 4 b.d.l. 35.338 b.d.l. 37.561 0.025 0 26.473 b.d.l. 0.187 0.009 02 oliv 7 b.d.l. 34.088 b.d.l. 37.554 b.d.l. 0 28.100 0.010 b.d.l. -0.001 02 oliv 7 b.d.l. 31.605 b.d.l. 37.238 b.d.l. 0 30.975 0.019 b.d.l. -0.001 02 oliv 8 b.d.l. 36.035 b.d.l. 37.645 0.023 0 25.699 0.038 b.d.l. 0.005 02 oliv 8 b.d.l. 34.516 b.d.l. 37.639 b.d.l. 0 27.205 0.038 0.211 0.008 02 oliv 8 b.d.l. 31.975 b.d.l. 36.824 0.022 0 30.086 0.009 b.d.l. 0.002 04 oliv 1 b.d.l. 44.000 b.d.l. 39.497 b.d.l. 0 16.126 0.008 0.163 0.007 04 oliv 1 b.d.l. 44.083 b.d.l. 39.611 b.d.l. 0 16.173 0.017 0.162 0.010 04 oliv 1 b.d.l. 44.182 b.d.l. 39.665 b.d.l. 0 16.266 0.019 0.164 0.016 04 oliv 1 b.d.l. 44.151 b.d.l. 39.686 0.014 0 16.258 0.009 0.152 0.011 04 oliv 1 b.d.l. 44.031 b.d.l. 39.569 b.d.l. 0 16.161 0.011 0.162 0.006 04 oliv 1 b.d.l. 37.715 b.d.l. 38.136 0.020 0 23.572 b.d.l. b.d.l. 0.003 04 oliv 2 b.d.l. 44.198 b.d.l. 39.419 b.d.l. 0 16.152 b.d.l. 0.143 0.020 84

Sample Na2O MgO Al2O3 SiO2 TiO2 V2O3 FeO P2O5 CaO Cr2O3 04 oliv 2 b.d.l. 37.318 b.d.l. 37.747 b.d.l. 0 24.230 b.d.l. b.d.l. 0.000 04 oliv 3 b.d.l. 43.421 b.d.l. 38.644 b.d.l. 0 17.160 0.017 0.159 0.008 04 oliv 3 b.d.l. 37.068 b.d.l. 37.747 0.015 0 24.275 0.009 0.175 0.008 04 oliv 4 b.d.l. 44.240 b.d.l. 39.254 b.d.l. 0 16.365 0.009 0.166 0.018 04 oliv 4 b.d.l. 38.422 b.d.l. 38.313 b.d.l. 0 22.674 0.008 0.175 0.024 04 oliv 5 b.d.l. 46.698 b.d.l. 40.285 b.d.l. 0 13.023 b.d.l. 0.141 0.029 04 oliv 5 b.d.l. 46.403 b.d.l. 40.195 b.d.l. 0 13.078 b.d.l. 0.144 0.033 04 oliv 5 b.d.l. 46.392 b.d.l. 40.186 b.d.l. 0 13.435 b.d.l. 0.146 0.022 04 oliv 5 b.d.l. 46.187 b.d.l. 40.148 b.d.l. 0 13.731 b.d.l. 0.148 0.027 04 oliv 5 b.d.l. 45.431 b.d.l. 39.850 b.d.l. 0 14.701 0.017 0.149 0.016 04 oliv 5 b.d.l. 43.479 b.d.l. 39.396 b.d.l. 0 16.842 0.012 0.156 0.024 04 oliv 6 b.d.l. 47.542 b.d.l. 40.246 b.d.l. 0 11.963 b.d.l. 0.139 0.030 04 oliv 6 b.d.l. 47.471 b.d.l. 40.223 b.d.l. 0 12.004 b.d.l. 0.132 0.021 04 oliv 6 b.d.l. 47.608 b.d.l. 40.329 b.d.l. 0 12.008 0.008 0.136 0.017 04 oliv 6 b.d.l. 47.644 b.d.l. 40.411 b.d.l. 0 12.110 0.011 0.129 0.025 04 oliv 6 b.d.l. 47.662 b.d.l. 40.410 0.015 0 12.172 b.d.l. 0.135 0.033 04 oliv 6 b.d.l. 47.577 b.d.l. 40.448 b.d.l. 0 12.094 b.d.l. 0.134 0.024 04 oliv 6 b.d.l. 47.427 b.d.l. 40.443 b.d.l. 0 12.092 b.d.l. 0.133 0.023 04 oliv 6 b.d.l. 47.310 0.016 40.236 b.d.l. 0 12.118 0.010 0.142 0.128 04 oliv 6 b.d.l. 47.520 b.d.l. 40.358 b.d.l. 0 12.144 0.007 0.136 0.020 04 oliv 6 b.d.l. 47.632 b.d.l. 40.198 b.d.l. 0 12.120 0.010 0.138 0.051 04 oliv 6 b.d.l. 47.553 b.d.l. 40.118 b.d.l. 0 12.214 0.009 0.138 0.024 04 oliv 6 b.d.l. 47.537 b.d.l. 40.132 b.d.l. 0 12.298 b.d.l. 0.131 0.022 04 oliv 6 b.d.l. 47.330 b.d.l. 40.258 b.d.l. 0 12.344 b.d.l. 0.134 0.024 04 oliv 6 b.d.l. 47.072 b.d.l. 40.153 b.d.l. 0 12.610 b.d.l. 0.130 0.029 04 oliv 6 b.d.l. 46.806 b.d.l. 40.117 b.d.l. 0 13.064 0.010 0.134 0.022 04 oliv 6 b.d.l. 46.286 b.d.l. 40.111 b.d.l. 0 13.680 b.d.l. 0.132 0.019 04 oliv 6 b.d.l. 44.506 b.d.l. 39.757 b.d.l. 0 15.878 b.d.l. 0.138 0.020 04 oliv 6 b.d.l. 38.963 b.d.l. 38.524 b.d.l. 0 22.501 b.d.l. 0.165 0.009 04 oliv 6core b.d.l. 47.409 b.d.l. 40.136 b.d.l. 0 12.061 0.010 0.136 0.027 04 oliv 7 b.d.l. 42.979 b.d.l. 39.329 b.d.l. 0 17.259 b.d.l. 0.169 0.016 04 oliv 7 b.d.l. 44.005 b.d.l. 39.498 0.015 0 15.951 0.014 0.165 0.010 04 oliv 7 b.d.l. 41.435 b.d.l. 38.632 0.019 0 19.306 b.d.l. 0.158 0.005 04 oliv 7 b.d.l. 38.057 b.d.l. 37.709 b.d.l. 0 23.229 0.012 b.d.l. 0.004 04 oliv 8 b.d.l. 44.284 b.d.l. 39.429 b.d.l. 0 16.089 0.008 0.150 0.014 04 oliv 8 b.d.l. 44.307 b.d.l. 39.480 b.d.l. 0 16.124 0.029 0.160 0.013 04 oliv 8 b.d.l. 43.911 b.d.l. 39.464 0.013 0 16.593 b.d.l. 0.154 0.008 04 oliv 8 b.d.l. 42.426 b.d.l. 39.240 b.d.l. 0 18.299 0.011 0.152 0.011 04 oliv 8 b.d.l. 37.895 b.d.l. 38.342 0.016 0 23.178 0.016 0.196 0.018 09 oliv 1 b.d.l. 45.587 b.d.l. 39.766 b.d.l. 0 14.631 b.d.l. 0.139 0.013 09 oliv 1 0.010 45.641 b.d.l. 39.764 b.d.l. 0 14.750 b.d.l. 0.138 0.006 09 oliv 1 0.031 45.511 b.d.l. 39.762 b.d.l. 0 14.753 b.d.l. 0.142 0.009 09 oliv 1 0.010 45.596 b.d.l. 39.674 b.d.l. 0 14.752 b.d.l. 0.138 0.010 09 oliv 1 b.d.l. 45.543 b.d.l. 39.690 b.d.l. 0 14.814 b.d.l. 0.140 0.006 09 oliv 1 b.d.l. 45.479 b.d.l. 39.681 b.d.l. 0 14.965 0.009 0.138 0.011 09 oliv 1 b.d.l. 45.323 b.d.l. 39.628 b.d.l. 0 15.027 0.007 0.136 0.011 09 oliv 1 b.d.l. 45.171 b.d.l. 39.623 b.d.l. 0 15.196 0.012 0.135 0.013 85

Sample Na2O MgO Al2O3 SiO2 TiO2 V2O3 FeO P2O5 CaO Cr2O3 09 oliv 1 b.d.l. 44.879 b.d.l. 39.589 0.012 0 15.460 0.010 b.d.l. 0.005 09 oliv 1 b.d.l. 44.626 b.d.l. 39.639 b.d.l. 0 15.737 b.d.l. 0.141 0.012 09 oliv 1 b.d.l. 44.306 b.d.l. 39.487 0.012 0 16.246 0.009 0.142 0.006 09 oliv 1 b.d.l. 44.130 b.d.l. 39.532 b.d.l. 0 16.491 b.d.l. 0.145 0.019 09 oliv 1 b.d.l. 43.652 0.010 39.180 b.d.l. 0 16.893 b.d.l. 0.141 0.011 09 oliv 1 b.d.l. 43.144 0.009 39.294 b.d.l. 0 17.523 b.d.l. b.d.l. 0.005 09 oliv 1 b.d.l. 42.592 b.d.l. 39.006 b.d.l. 0 18.465 b.d.l. 0.147 0.010 09 oliv 1 b.d.l. 41.491 b.d.l. 38.836 b.d.l. 0 19.695 b.d.l. 0.156 0.007 09 oliv 1 0.010 40.063 b.d.l. 38.300 0.016 0 21.330 0.008 0.183 0.010 09 oliv 2 b.d.l. 42.631 b.d.l. 39.041 b.d.l. 0 18.311 b.d.l. 0.170 0.007 09 oliv 2 0.097 37.992 b.d.l. 37.759 0.021 0 23.535 0.010 0.214 0.008 09 oliv 3 b.d.l. 42.227 b.d.l. 39.158 0.016 0 18.921 0.021 0.172 0.007 09 oliv 3 b.d.l. 38.572 0.006 38.229 b.d.l. 0 22.818 0.011 b.d.l. 0.004 09 oliv 4 b.d.l. 42.181 b.d.l. 39.120 b.d.l. 0 18.788 0.008 0.177 0.010 09 oliv 4 0.013 39.096 b.d.l. 38.088 b.d.l. 0 22.596 0.021 0.214 0.011 09 oliv 5 b.d.l. 41.946 0.006 39.206 b.d.l. 0 18.839 0.083 0.184 0.013 09 oliv 5 b.d.l. 37.017 b.d.l. 38.001 0.016 0 24.465 0.015 b.d.l. 0.000 09 oliv 6 b.d.l. 42.022 0.008 39.127 b.d.l. 0 19.080 0.015 0.195 0.014 09 oliv 6 b.d.l. 36.483 b.d.l. 37.620 0.025 0 25.106 0.027 b.d.l. 0.003 25 oliv3 b.d.l. 35.352 b.d.l. 37.570 0.016 0 26.348 0.016 b.d.l. 0.000 25 oliv3 b.d.l. 31.008 b.d.l. 36.446 0.020 0 31.337 0.018 0.219 0.006 25 oliv4 b.d.l. 32.528 b.d.l. 36.722 0.014 0 29.850 0.012 0.240 0.007 25 oliv4 b.d.l. 28.853 b.d.l. 35.866 0.024 0 34.054 0.009 b.d.l. 0.000 25 oliv5 b.d.l. 30.067 b.d.l. 36.412 0.018 0 32.418 0.013 b.d.l. 0.005 25 oliv5 b.d.l. 30.031 b.d.l. 36.464 0.022 0 32.335 0.070 b.d.l. 0.002 25 oliv6 b.d.l. 31.287 b.d.l. 36.709 b.d.l. 0 30.982 0.015 b.d.l. 0.001 25 oliv6 b.d.l. 29.598 b.d.l. 36.183 0.014 0 33.271 0.042 b.d.l. -0.001 25 oliv7 b.d.l. 31.527 b.d.l. 36.767 0.020 0 30.748 0.012 b.d.l. -0.003 25 oliv7 b.d.l. 29.149 b.d.l. 36.172 0.021 0 33.605 0.021 b.d.l. -0.005 25 oliv8 b.d.l. 30.211 b.d.l. 36.436 b.d.l. 0 32.501 0.012 b.d.l. -0.002 25 oliv8 b.d.l. 29.543 b.d.l. 36.362 0.033 0 32.928 0.035 b.d.l. -0.003 29 oliv1 b.d.l. 34.308 b.d.l. 37.294 0.019 0 27.902 0.014 b.d.l. -0.002 29 oliv1 b.d.l. 33.704 b.d.l. 37.153 0.018 0 28.698 0.035 b.d.l. -0.003 29 oliv1 b.d.l. 33.199 b.d.l. 36.861 b.d.l. 0 29.166 0.066 b.d.l. 0.004 29 oliv3 b.d.l. 38.187 b.d.l. 37.983 b.d.l. 0 23.374 b.d.l. b.d.l. 0.002 29 oliv3 b.d.l. 33.548 b.d.l. 37.012 0.022 0 28.652 b.d.l. b.d.l. 0.002 29 oliv3 b.d.l. 33.884 b.d.l. 37.055 b.d.l. 0 28.226 0.012 b.d.l. 0.004 29 oliv4 b.d.l. 33.629 b.d.l. 37.106 b.d.l. 0 28.637 0.020 b.d.l. -0.004 29 oliv4 b.d.l. 33.737 b.d.l. 36.984 0.040 0 28.845 0.027 b.d.l. 0.002 29 oliv4 b.d.l. 32.996 b.d.l. 36.973 b.d.l. 0 29.464 0.016 b.d.l. 0.000 29 oliv5 b.d.l. 34.358 b.d.l. 37.340 b.d.l. 0 27.638 0.015 b.d.l. -0.006 29 oliv5 b.d.l. 33.662 b.d.l. 37.067 b.d.l. 0 28.778 0.016 b.d.l. 0.005 33 oliv 1 b.d.l. 41.551 b.d.l. 38.454 0.013 0 19.389 0.017 b.d.l. -0.002 33 oliv 1 b.d.l. 36.466 b.d.l. 37.816 0.015 0 25.196 0.012 b.d.l. 0.002 33 oliv 12 b.d.l. 41.438 b.d.l. 38.740 b.d.l. 0 19.394 b.d.l. 0.143 0.012 33 oliv 12 b.d.l. 34.415 b.d.l. 36.956 b.d.l. 0 27.373 b.d.l. b.d.l. 0.001 33 oliv 13 b.d.l. 38.494 b.d.l. 37.844 b.d.l. 0 22.934 0.009 b.d.l. 0.003 86

Sample Na2O MgO Al2O3 SiO2 TiO2 V2O3 FeO P2O5 CaO Cr2O3 33 oliv 13 b.d.l. 33.951 b.d.l. 37.278 0.014 0 28.007 0.016 b.d.l. -0.005 33 oliv 14 b.d.l. 40.851 b.d.l. 38.448 0.015 0 20.344 0.008 0.175 0.007 33 oliv 14 0.008 37.008 b.d.l. 37.726 b.d.l. 0 24.704 0.039 b.d.l. 0.002 33 oliv 14 b.d.l. 37.390 b.d.l. 37.871 0.015 0 24.409 0.036 b.d.l. 0.002 33 oliv 14 b.d.l. 36.777 b.d.l. 37.787 b.d.l. 0 24.952 0.014 b.d.l. -0.004 33 oliv 14 b.d.l. 34.234 b.d.l. 37.085 b.d.l. 0 27.875 0.013 b.d.l. 0.005 33 oliv 14 b.d.l. 33.032 b.d.l. 37.056 b.d.l. 0 28.739 0.014 b.d.l. -0.005 33 oliv 5 b.d.l. 41.531 b.d.l. 38.798 0.016 0 19.267 0.015 0.137 0.006 33 oliv 5 b.d.l. 35.497 b.d.l. 37.508 b.d.l. 0 26.445 b.d.l. 0.179 0.008 33 oliv 5 b.d.l. 36.753 b.d.l. 37.501 0.017 0 25.106 0.014 b.d.l. 0.004 33 oliv 5 b.d.l. 39.358 b.d.l. 38.088 0.014 0 21.979 0.008 b.d.l. 0.004 33 oliv 5 b.d.l. 40.793 0.106 38.501 b.d.l. 0 20.344 0.020 0.140 0.008 33 oliv 5 b.d.l. 41.377 b.d.l. 38.869 b.d.l. 0 19.620 0.022 0.136 0.013 33 oliv 5 b.d.l. 41.443 b.d.l. 38.807 b.d.l. 0 19.459 0.020 b.d.l. 0.003 33 oliv 5 b.d.l. 41.417 b.d.l. 38.733 b.d.l. 0 19.395 0.023 b.d.l. 0.003 33 oliv 5 b.d.l. 41.436 b.d.l. 38.642 b.d.l. 0 19.316 0.022 0.164 0.006 33 oliv 5 b.d.l. 41.435 b.d.l. 38.676 0.012 0 19.200 0.008 0.155 0.006 33 oliv 5 b.d.l. 41.458 b.d.l. 38.709 b.d.l. 0 19.293 0.023 0.140 0.014 33 oliv 5 b.d.l. 41.417 b.d.l. 38.923 b.d.l. 0 19.322 0.026 0.133 0.007 33 oliv 5 b.d.l. 40.817 b.d.l. 38.757 b.d.l. 0 19.941 0.027 0.136 0.007 33 oliv 5 b.d.l. 37.971 b.d.l. 38.258 b.d.l. 0 23.367 b.d.l. b.d.l. 0.004 33 oliv 7 b.d.l. 38.092 b.d.l. 37.497 b.d.l. 0 23.528 0.007 b.d.l. 0.003 33 oliv 7 b.d.l. 39.271 b.d.l. 38.319 0.015 0 21.886 b.d.l. 0.157 0.010 33 oliv 7 b.d.l. 37.399 b.d.l. 37.756 0.021 0 24.231 0.011 b.d.l. 0.003 36 oliv-12 b.d.l. 42.018 b.d.l. 39.148 b.d.l. 0 18.535 0.011 0.110 0.012 36 oliv-12 b.d.l. 41.481 b.d.l. 39.105 b.d.l. 0 19.157 b.d.l. 0.130 0.008 36 oliv-12 b.d.l. 33.204 b.d.l. 37.030 0.012 0 28.778 0.010 b.d.l. 0.000 36 oliv-12 b.d.l. 35.876 b.d.l. 37.736 0.022 0 25.343 0.008 b.d.l. 0.003 36 oliv-13 b.d.l. 42.096 b.d.l. 39.226 b.d.l. 0 18.388 0.008 0.143 0.014 36 oliv-13 b.d.l. 41.891 b.d.l. 39.255 b.d.l. 0 18.569 0.010 b.d.l. 0.003 36 oliv-13 b.d.l. 39.940 b.d.l. 38.647 0.018 0 21.285 b.d.l. 0.169 0.011 36 oliv-14 b.d.l. 40.333 b.d.l. 38.895 b.d.l. 0 20.355 b.d.l. 0.136 0.008 36 oliv-14 b.d.l. 38.430 b.d.l. 38.689 0.013 0 22.612 b.d.l. b.d.l. 0.004 36 oliv-14 b.d.l. 35.580 b.d.l. 37.790 0.021 0 26.077 0.015 b.d.l. -0.001 36 oliv-15 b.d.l. 41.267 b.d.l. 39.054 b.d.l. 0 19.243 0.028 0.136 0.008 36 oliv-15 b.d.l. 36.829 b.d.l. 38.295 0.021 0 24.813 0.021 b.d.l. 0.004 36 oliv-16 b.d.l. 42.134 b.d.l. 39.107 b.d.l. 0 18.339 0.017 0.112 0.013 36 oliv-16 b.d.l. 35.696 0.047 37.550 0.028 0 25.182 0.036 b.d.l. 0.002 36 oliv-17 b.d.l. 41.372 b.d.l. 39.084 b.d.l. 0 18.917 0.018 0.144 0.020 36 oliv-17 b.d.l. 41.608 b.d.l. 38.651 b.d.l. 0 19.058 0.009 0.142 0.013 36 oliv-17 b.d.l. 36.115 b.d.l. 38.144 0.012 0 26.057 0.008 0.170 0.009 36 oliv-17 b.d.l. 35.762 b.d.l. 37.733 b.d.l. 0 25.004 0.014 0.166 0.010 87

Sample MnO NiO TOTAL 01 oliv_5 0.273 0.101 100.19 01 oliv_5 0.408 b.d.l. 100.19 01 oliv-5 0.284 0.102 100.24 01 oliv-6 0.265 0.117 100.21 01 oliv-6 0.286 0.144 100.23 01 oliv-6 0.285 0.117 100.26 01 oliv-6 0.469 b.d.l. 99.790 01 oliv-6 0.415 0.070 100.09 01 oliv-7 0.246 0.167 99.929 01 oliv-7 0.244 0.186 100.07 01 oliv-7 0.245 0.191 100.31 01 oliv-7 0.378 b.d.l. 100.13 01 oliv-7 0.465 b.d.l. 99.905 01 oliv-7 0.261 0.186 100.07 01 oliv-8 0.259 0.106 99.957 01 oliv-8 0.456 0.068 99.755 01 oliv-9 0.499 0.065 99.900 01 oliv-9 0.267 0.101 99.971 01 oliv-10 0.345 0.085 99.704 01 oliv-10 0.487 0.054 99.521 01 oliv-11 0.455 0.072 99.953 01 oliv-11 0.204 0.218 100.01 02 oliv 1 0.269 0.148 99.960 02 oliv 1 0.469 0.058 100.07 02 oliv 2 0.289 0.135 100.47 02 oliv 2 0.331 0.106 100.26 02 oliv 2 0.560 0.057 99.848 02 oliv 3 0.276 0.135 100.54 02 oliv 3 0.621 b.d.l. 99.993 02 oliv 4 0.290 0.108 100.57 02 oliv 4 0.531 0.061 100.16 02 oliv 7 0.558 b.d.l. 100.50 02 oliv 7 0.627 0.037 100.70 02 oliv 8 0.478 b.d.l. 100.17 02 oliv 8 0.528 b.d.l. 100.17 02 oliv 8 0.629 0.025 99.739 04 oliv 1 0.258 0.109 100.15 04 oliv 1 0.259 0.117 100.42 04 oliv 1 0.263 0.101 100.67 04 oliv 1 0.259 0.105 100.63 04 oliv 1 0.272 0.101 100.30 04 oliv 1 0.415 0.072 100.10 04 oliv 2 0.259 0.158 100.34 88

Sample MnO NiO TOTAL 04 oliv 2 0.427 0.089 99.985 04 oliv 3 0.295 0.112 99.799 04 oliv 3 0.440 b.d.l. 99.819 04 oliv 4 0.266 0.101 100.40 04 oliv 4 0.391 0.099 100.09 04 oliv 5 0.195 0.197 100.55 04 oliv 5 0.194 0.187 100.23 04 oliv 5 0.211 0.176 100.55 04 oliv 5 0.209 0.174 100.61 04 oliv 5 0.230 0.160 100.53 04 oliv 5 0.287 0.134 100.31 04 oliv 6 0.178 0.226 100.33 04 oliv 6 0.167 0.226 100.24 04 oliv 6 0.174 0.229 100.50 04 oliv 6 0.176 0.233 100.73 04 oliv 6 0.187 0.242 100.85 04 oliv 6 0.188 0.229 100.69 04 oliv 6 0.171 0.238 100.51 04 oliv 6 0.184 0.229 100.37 04 oliv 6 0.187 0.234 100.60 04 oliv 6 0.177 0.234 100.55 04 oliv 6 0.183 0.247 100.48 04 oliv 6 0.182 0.236 100.53 04 oliv 6 0.187 0.228 100.50 04 oliv 6 0.176 b.d.l. 100.40 04 oliv 6 0.198 0.218 100.56 04 oliv 6 0.205 0.191 100.63 04 oliv 6 0.227 b.d.l. 100.68 04 oliv 6 0.388 0.106 100.64 04 oliv 6core 0.177 0.234 100.18 04 oliv 7 0.297 0.100 100.15 04 oliv 7 0.266 0.099 100.00 04 oliv 7 0.345 b.d.l. 99.991 04 oliv 7 0.413 b.d.l. 99.719 04 oliv 8 0.260 0.112 100.34 04 oliv 8 0.274 0.118 100.49 04 oliv 8 0.271 0.104 100.51 04 oliv 8 0.298 0.088 100.51 04 oliv 8 0.433 0.090 100.16 09 oliv 1 0.195 b.d.l. 100.62 09 oliv 1 0.201 0.271 100.79 09 oliv 1 0.200 0.273 100.69 09 oliv 1 0.204 b.d.l. 100.65 09 oliv 1 0.200 b.d.l. 100.68 09 oliv 1 0.201 b.d.l. 100.77 09 oliv 1 0.209 b.d.l. 100.63 09 oliv 1 0.208 0.260 100.62 89

Sample MnO NiO TOTAL 09 oliv 1 0.216 0.259 100.57 09 oliv 1 0.226 b.d.l. 100.62 09 oliv 1 0.236 0.233 100.68 09 oliv 1 0.249 0.225 100.79 09 oliv 1 0.243 b.d.l. 100.33 09 oliv 1 0.261 b.d.l. 100.57 09 oliv 1 0.302 b.d.l. 100.68 09 oliv 1 0.311 b.d.l. 100.63 09 oliv 1 0.370 b.d.l. 100.38 09 oliv 2 0.286 b.d.l. 100.58 09 oliv 2 0.454 0.064 100.14 09 oliv 3 0.315 b.d.l. 100.95 09 oliv 3 0.449 0.085 100.39 09 oliv 4 0.316 b.d.l. 100.69 09 oliv 4 0.442 b.d.l. 100.56 09 oliv 5 0.317 b.d.l. 100.71 09 oliv 5 0.498 0.055 100.31 09 oliv 6 0.321 b.d.l. 100.90 09 oliv 6 0.499 b.d.l. 100.04 25 oliv3 0.440 0.062 100.04 25 oliv3 0.547 0.033 99.617 25 oliv4 0.511 0.041 99.898 25 oliv4 0.595 0.031 99.594 25 oliv5 0.564 b.d.l. 99.758 25 oliv5 0.564 b.d.l. 99.752 25 oliv6 0.537 0.045 99.810 25 oliv6 0.565 0.041 99.923 25 oliv7 0.541 0.057 99.897 25 oliv7 0.562 0.025 99.747 25 oliv8 0.547 0.045 99.981 25 oliv8 0.568 b.d.l. 99.692 29 oliv1 0.534 b.d.l. 100.31 29 oliv1 0.561 0.046 100.35 29 oliv1 0.560 0.068 100.07 29 oliv3 0.426 0.092 100.19 29 oliv3 0.541 0.081 99.988 29 oliv3 0.521 0.082 99.946 29 oliv4 0.526 0.066 100.16 29 oliv4 0.538 b.d.l. 100.35 29 oliv4 0.545 0.065 100.20 29 oliv5 0.525 0.079 100.12 29 oliv5 0.552 0.073 100.31 33 oliv 1 0.317 0.098 99.976 33 oliv 1 0.457 0.078 100.22 33 oliv 12 0.318 0.114 100.16 33 oliv 12 0.508 b.d.l. 99.523 33 oliv 13 0.451 b.d.l. 99.989 90

Sample MnO NiO TOTAL 33 oliv 13 0.526 0.046 100.04 33 oliv 14 0.318 0.106 100.26 33 oliv 14 0.422 0.090 100.14 33 oliv 14 0.412 0.082 100.37 33 oliv 14 0.436 0.086 100.19 33 oliv 14 0.513 b.d.l. 100.02 33 oliv 14 0.540 0.047 99.633 33 oliv 5 0.303 0.106 100.17 33 oliv 5 0.482 0.078 100.17 33 oliv 5 0.451 0.087 100.09 33 oliv 5 0.373 0.102 100.04 33 oliv 5 0.322 0.104 100.34 33 oliv 5 0.316 0.106 100.46 33 oliv 5 0.318 0.113 100.30 33 oliv 5 0.313 0.117 100.14 33 oliv 5 0.308 b.d.l. 100.01 33 oliv 5 0.308 0.125 99.915 33 oliv 5 0.319 0.100 100.05 33 oliv 5 0.316 0.113 100.26 33 oliv 5 0.328 0.113 100.13 33 oliv 5 0.409 0.111 100.27 33 oliv 7 0.482 0.111 99.862 33 oliv 7 0.407 0.099 100.15 33 oliv 7 0.447 0.082 100.10 36 oliv-12 0.293 0.197 100.32 36 oliv-12 0.324 0.121 100.31 36 oliv-12 0.449 b.d.l. 99.711 36 oliv-12 0.496 b.d.l. 99.746 36 oliv-13 0.299 0.099 100.26 36 oliv-13 0.319 0.107 100.30 36 oliv-13 0.400 b.d.l. 100.53 36 oliv-14 0.372 0.148 100.23 36 oliv-14 0.436 b.d.l. 100.45 36 oliv-14 0.512 0.047 100.26 36 oliv-15 0.318 0.111 100.16 36 oliv-15 0.483 0.055 100.69 36 oliv-16 0.279 0.182 100.16 36 oliv-16 0.487 b.d.l. 99.299 36 oliv-17 0.319 0.102 99.974 36 oliv-17 0.322 0.107 99.907 36 oliv-17 0.493 b.d.l. 101.07 36 oliv-17 0.462 0.094 99.233 91

Table A6. WUSTL electron microprobe data for oxide phenocrysts within the following samples: MP-17-01, 02, 04, 09, 25, 29, 33, 36. Detection limit was analyzed at 99% confidence level (3σ) (b.d.l.=below detection limit).

SAMPLE Na2O MgO Al2O3 SiO2 TiO2 V2O3 Fe3O4 01 oliv 10_oxide b.d.l. 1.784 1.481 b.d.l. 14.352 0.893 80.046 01 oliv 10_oxide b.d.l. 2.974 2.250 b.d.l. 14.515 0.940 78.245 01 oliv 10_oxide b.d.l. 1.478 1.765 b.d.l. 12.685 0.838 82.626 01 oliv 11_oxide b.d.l. 2.927 4.708 b.d.l. 5.787 0.512 69.234 01 oliv 11_oxide b.d.l. 2.901 4.649 b.d.l. 5.867 0.551 69.717 01 oliv 11_oxide2 b.d.l. 10.404 24.177 b.d.l. 0.365 0.109 35.221 01 oliv 11_oxide2 b.d.l. 7.772 15.461 b.d.l. 1.844 0.263 51.783 01 oliv 11_oxide2 b.d.l. 8.650 16.030 b.d.l. 1.549 0.276 46.096 01 oliv 11_oxide2 b.d.l. 9.375 21.115 b.d.l. 0.590 0.116 39.598 01 oliv 6_oxide b.d.l. 8.284 15.593 b.d.l. 1.082 0.203 45.685 01 oliv 6_oxide b.d.l. 5.674 8.807 b.d.l. 3.135 0.278 61.551 01 oliv 6_oxide b.d.l. 3.429 3.558 b.d.l. 9.283 0.712 76.247 01 oliv 6_oxide b.d.l. 2.941 3.139 b.d.l. 10.102 0.740 78.712 01 oliv 7_oxide b.d.l. 10.015 21.026 b.d.l. 0.497 0.124 34.636 01 oliv 7_oxide b.d.l. 9.430 20.237 b.d.l. 0.669 0.159 40.120 01 oliv 7_oxide b.d.l. 8.486 18.441 b.d.l. 1.806 0.235 52.011 01 oliv 7_oxide b.d.l. 10.717 20.479 b.d.l. 1.424 0.283 45.051 01 oliv 7_oxide b.d.l. 9.338 20.101 b.d.l. 0.586 0.151 38.687 01 oliv 7_oxide b.d.l. 3.314 4.059 b.d.l. 7.267 0.573 74.229 01 oliv 7_oxide b.d.l. 1.511 2.252 b.d.l. 10.598 0.800 80.346 01 oliv 8_oxide b.d.l. 2.818 2.765 b.d.l. 12.361 0.878 80.184 01 oliv 8_oxide b.d.l. 1.641 1.847 b.d.l. 12.233 0.833 83.104 01 oliv 9_oxide 0.014 1.799 1.559 b.d.l. 15.148 0.991 79.943 01 oliv 9_oxide b.d.l. 1.648 1.472 b.d.l. 14.651 0.922 80.319 01 oliv 9_oxide b.d.l. 0.919 1.258 b.d.l. 14.020 0.866 82.650 02 oliv 2_oxide b.d.l. 3.470 5.136 0.078 9.725 0.727 73.259 02 oliv 2_oxide b.d.l. 0.691 1.192 0.106 11.553 1.182 83.443 02 oliv 3_oxide b.d.l. 4.642 9.952 b.d.l. 3.516 0.370 63.726 02 oliv 3_oxide b.d.l. 3.408 5.046 b.d.l. 8.965 0.762 73.891 02 oliv 3_oxide b.d.l. 0.705 0.873 b.d.l. 10.031 1.016 86.066 04 oliv 1_oxide b.d.l. 8.608 17.208 b.d.l. 1.680 0.247 47.256 04 oliv 1_oxide b.d.l. 4.729 7.525 b.d.l. 4.151 0.351 60.488 04 oliv 1_oxide b.d.l. 3.428 4.943 0.208 5.571 0.460 69.114 04 oliv 5_oxide1 b.d.l. 12.037 28.057 b.d.l. 0.485 0.123 30.260 04 oliv 5_oxide2 b.d.l. 11.603 26.745 b.d.l. 0.531 0.135 31.072 04 oliv 6_oxide1 b.d.l. 13.388 29.737 b.d.l. 0.428 0.143 26.347 04 oliv 6_oxide2 b.d.l. 13.442 30.138 0.124 0.409 0.135 25.744 09 oliv 1_oxide1 0.072 6.873 15.594 b.d.l. 2.649 0.387 53.667 09 oliv 3_oxide1 b.d.l. 7.398 16.312 b.d.l. 2.665 0.359 51.560 09 oliv 4_oxide1 0.025 6.156 12.689 b.d.l. 4.326 0.432 56.449 09 oliv 5_oxide1 b.d.l. 5.520 10.416 b.d.l. 3.226 0.370 60.467 09 oliv 5_oxide2 b.d.l. 5.629 12.089 b.d.l. 2.898 0.355 58.178 25 ilm1 b.d.l. 3.232 0.199 0.052 39.180 0.304 53.025 92

SAMPLE Na2O MgO Al2O3 SiO2 TiO2 V2O3 Fe3O4 25 ilm2 b.d.l. 2.531 0.185 b.d.l. 43.181 0.295 51.934 25 ilm3 0.049 1.627 1.200 2.260 21.874 0.247 57.569 25 ilm4_tp b.d.l. 2.755 0.110 b.d.l. 46.183 0.216 49.418 25 ilm5 b.d.l. 1.713 0.596 b.d.l. 25.370 0.361 68.261 25 mt2_tp b.d.l. 0.826 3.359 b.d.l. 5.577 0.832 88.340 25 mt4 b.d.l. 1.226 2.880 b.d.l. 13.115 1.002 81.364 25 mt5 0.487 0.191 0.016 1.386 b.d.l. 0.059 87.107 25 mt5-2 b.d.l. 0.997 3.448 b.d.l. 4.183 0.779 90.084 25 oliv3_oxide1 b.d.l. 1.199 5.395 b.d.l. 5.170 1.096 80.524 25 oliv4_oxide1 b.d.l. 0.349 0.333 b.d.l. 0.058 0.022 94.133 29 ilm1 b.d.l. 2.330 0.035 b.d.l. 45.057 0.232 50.193 29 ilm2 b.d.l. 2.350 0.042 b.d.l. 45.310 0.272 51.218 29 ilm3 b.d.l. 3.232 0.101 b.d.l. 45.767 0.237 49.783 29 ilm4 b.d.l. 2.145 0.042 b.d.l. 44.016 0.297 50.803 29 mt1 b.d.l. 2.667 2.127 b.d.l. 13.946 0.848 78.194 29 mt2_tp b.d.l. 0.865 1.155 b.d.l. 7.563 1.234 88.141 29 mt3_tp b.d.l. 1.215 1.835 b.d.l. 8.286 1.060 86.589 29 mt4_tp b.d.l. 0.969 1.099 b.d.l. 8.086 1.157 88.104 29 oliv3_oxide1 b.d.l. 2.229 2.450 b.d.l. 12.005 0.957 80.930 29 oliv4_oxide1 b.d.l. 1.833 4.318 b.d.l. 7.371 0.690 85.239 29 oliv4_oxide2 b.d.l. 1.613 5.297 b.d.l. 7.226 0.717 83.876 33 oliv 1_oxide b.d.l. 3.588 3.368 b.d.l. 11.182 0.838 75.279 33 oliv 1_oxide b.d.l. 2.549 2.097 b.d.l. 13.002 0.923 80.111 33 oliv 14_oxide b.d.l. 2.203 1.218 0.703 13.116 0.857 80.118 33 oliv 14_oxide b.d.l. 3.044 6.693 0.289 3.473 0.522 72.833 33 oliv 14_oxide b.d.l. 2.895 2.516 b.d.l. 13.400 0.969 77.949 33 oliv 5_oxide b.d.l. 3.112 1.831 1.719 14.297 0.903 75.601 33 oliv 5_oxide b.d.l. 2.732 2.435 b.d.l. 12.493 0.843 77.978 33 oliv 5_oxide b.d.l. 2.689 2.431 b.d.l. 12.105 0.809 77.202 33 oliv 5_oxide b.d.l. 1.965 1.289 b.d.l. 13.744 0.946 81.268 33 oliv 5_oxide b.d.l. 3.004 2.557 b.d.l. 12.492 0.840 77.097 33 oliv 5_oxide b.d.l. 2.701 2.507 0.317 12.284 0.829 76.948 33 oliv 7_ilm b.d.l. 1.538 0.795 1.378 18.365 0.812 74.400 33 oliv 7_oxide b.d.l. 5.442 11.047 b.d.l. 4.060 0.504 66.236 33 oliv 7_oxide b.d.l. 3.705 6.570 0.646 6.912 0.750 66.183 33 oliv 7_oxide b.d.l. 3.852 3.442 b.d.l. 12.484 0.897 69.109 33 oliv 7_oxide b.d.l. 3.565 2.964 b.d.l. 11.431 1.072 70.337 33 oliv 7_oxide b.d.l. 1.755 1.478 b.d.l. 13.963 0.925 80.689 33 oliv 7_oxide 0.037 3.162 0.883 5.970 10.430 0.952 78.027 33 oliv 7_oxide b.d.l. 0.792 1.976 b.d.l. 10.803 1.273 81.257 33 oliv 7_oxide b.d.l. 3.075 2.444 0.155 14.802 0.977 76.373 33_ilm1 0.090 3.063 1.421 3.826 14.981 0.711 73.656 33_ilm2 0.038 2.782 0.388 0.523 37.013 0.384 54.782 33_ilm3 0.069 1.571 0.271 0.931 45.034 0.323 48.995 33_ilm4 0.067 1.668 0.368 0.773 45.031 0.337 47.252 33_ilm5 b.d.l. 1.633 0.016 0.047 44.936 0.254 49.852 33_ilm6 0.097 1.994 0.814 0.935 31.065 0.550 62.232 93

SAMPLE Na2O MgO Al2O3 SiO2 TiO2 V2O3 Fe3O4 33_mt1 b.d.l. 0.907 1.193 0.034 9.141 0.922 85.304 33_mt1-2 b.d.l. 2.002 1.047 b.d.l. 14.954 0.886 78.800 33_mt2 b.d.l. 1.907 0.934 b.d.l. 15.776 0.786 79.035 33_mt3 b.d.l. 1.670 1.077 0.264 16.389 0.841 77.357 33_mt4 b.d.l. 0.967 1.242 b.d.l. 9.246 0.985 85.085 33_mt5 b.d.l. 0.664 0.636 b.d.l. 8.196 0.971 87.266 33_mt6 b.d.l. 1.890 1.036 b.d.l. 15.996 0.838 78.942 36 newsite55_ilm b.d.l. 1.348 0.082 0.028 42.506 0.212 51.671 36 newsite55_mt b.d.l. 1.104 0.588 0.068 15.518 0.689 79.255 36 oliv 14_oxide b.d.l. 3.975 5.292 b.d.l. 6.060 0.518 75.791 36 oliv 14_oxide b.d.l. 2.555 3.645 b.d.l. 9.855 0.742 80.453 36 oliv 14_oxide b.d.l. 2.363 3.633 b.d.l. 9.754 0.709 80.304 36 oliv 14_oxide b.d.l. 3.370 5.373 b.d.l. 4.583 0.464 74.881 36 oliv 17_oxide b.d.l. 4.352 10.512 0.453 4.119 0.450 66.271 36 oliv 17_oxide b.d.l. 5.952 13.140 b.d.l. 3.713 0.477 63.116 36 oliv 17_oxide b.d.l. 6.090 13.625 b.d.l. 3.491 0.461 61.707 36 oliv 17_oxide b.d.l. 0.979 1.270 b.d.l. 11.683 0.776 82.150 36_ilm2 0.033 0.910 0.745 0.575 36.409 0.364 54.543 36_ilm3 b.d.l. 1.146 0.087 0.076 46.346 0.156 49.752 36_ilm4 b.d.l. 1.343 0.227 0.424 44.505 0.217 50.761 36_ilm5 0.230 1.181 0.552 2.014 43.762 0.198 49.884 36_ilm6 b.d.l. 0.977 0.115 0.080 45.003 0.195 50.895 36_mt2 0.022 0.546 1.175 0.020 12.496 0.897 81.664 36_mt3 0.014 0.419 2.529 0.852 11.754 0.878 76.192 36_mt3-2 b.d.l. 0.634 1.363 b.d.l. 13.047 0.923 80.593 36_mt4 b.d.l. 1.008 0.517 b.d.l. 22.723 0.729 72.173 36_mt5 0.145 0.322 1.211 0.761 8.101 0.994 84.250 36_mt5-2 b.d.l. 0.943 0.638 1.082 10.235 0.912 84.735 36_mt6 0.020 0.656 1.229 0.992 13.694 0.878 79.642 94

SAMPLE P2O5 CaO Cr2O3 MnO NiO TOTAL 01 oliv 10_oxide b.d.l. 0.204 0.081 0.476 b.d.l. 99.24 01 oliv 10_oxide b.d.l. 0.144 0.052 0.440 0.017 99.51 01 oliv 10_oxide b.d.l. 0.137 0.217 0.434 b.d.l. 100.14 01 oliv 11_oxide 0.015 0.015 16.437 0.377 0.038 99.92 01 oliv 11_oxide b.d.l. 0.020 15.570 0.379 0.034 99.62 01 oliv 11_oxide2 b.d.l. b.d.l. 30.101 0.298 0.104 100.64 01 oliv 11_oxide2 b.d.l. 0.006 22.922 0.338 0.092 100.35 01 oliv 11_oxide2 b.d.l. 0.012 27.408 0.348 0.092 100.32 01 oliv 11_oxide2 b.d.l. 0.018 29.209 0.291 0.141 100.32 01 oliv 6_oxide b.d.l. 0.000 27.880 0.342 0.131 99.08 01 oliv 6_oxide b.d.l. 0.012 19.806 0.352 0.082 99.54 01 oliv 6_oxide b.d.l. 0.038 6.790 0.379 0.037 100.37 01 oliv 6_oxide 0.009 0.076 3.976 0.380 0.041 100.05 01 oliv 7_oxide b.d.l. 0.006 34.174 0.298 0.126 100.75 01 oliv 7_oxide b.d.l. 0.002 29.732 0.287 0.130 100.63 01 oliv 7_oxide b.d.l. 0.025 19.181 0.329 0.099 100.49 01 oliv 7_oxide b.d.l. 0.115 21.695 0.303 0.131 100.05 01 oliv 7_oxide b.d.l. 0.002 31.290 0.309 0.124 100.45 01 oliv 7_oxide b.d.l. 0.014 10.598 0.383 0.026 100.34 01 oliv 7_oxide b.d.l. 0.037 4.618 0.431 0.012 100.49 01 oliv 8_oxide b.d.l. 0.033 1.603 0.404 0.025 100.98 01 oliv 8_oxide b.d.l. 0.065 0.775 0.405 b.d.l. 100.84 01 oliv 9_oxide b.d.l. 0.093 0.079 0.468 0.012 100.03 01 oliv 9_oxide b.d.l. 0.163 0.132 0.452 0.016 99.69 01 oliv 9_oxide b.d.l. 0.089 0.222 0.455 b.d.l. 100.39 02 oliv 2_oxide b.d.l. 0.018 6.976 0.435 0.055 99.87 02 oliv 2_oxide b.d.l. 0.068 0.308 0.420 b.d.l. 98.97 02 oliv 3_oxide b.d.l. 0.042 17.410 0.395 0.056 99.96 02 oliv 3_oxide b.d.l. 0.020 7.502 0.432 0.060 99.96 02 oliv 3_oxide b.d.l. 0.097 0.111 0.415 b.d.l. 99.28 04 oliv 1_oxide b.d.l. 0.012 23.680 0.326 0.091 99.05 04 oliv 1_oxide b.d.l. 0.041 21.062 0.386 0.057 98.69 04 oliv 1_oxide b.d.l. 0.075 13.004 0.380 0.041 97.23 04 oliv 5_oxide1 b.d.l. 0.004 28.636 0.260 0.152 99.92 04 oliv 5_oxide2 b.d.l. 0.003 29.115 0.270 0.132 99.54 04 oliv 6_oxide1 b.d.l. 0.006 30.013 0.238 0.176 100.37 04 oliv 6_oxide2 b.d.l. 0.010 29.460 0.238 0.184 99.89 09 oliv 1_oxide1 b.d.l. 0.027 20.610 0.338 0.102 100.18 09 oliv 3_oxide1 b.d.l. 0.011 21.197 0.346 0.095 99.84 09 oliv 4_oxide1 b.d.l. 0.006 18.739 0.367 0.085 99.18 09 oliv 5_oxide1 b.d.l. 0.012 20.083 0.377 0.056 100.44 09 oliv 5_oxide2 b.d.l. 0.014 20.184 0.395 0.062 99.70 25 ilm1 b.d.l. 0.197 0.043 0.729 b.d.l. 96.94 95

SAMPLE P2O5 CaO Cr2O3 MnO NiO TOTAL 25 ilm2 b.d.l. 0.051 0.025 0.761 b.d.l. 98.83 25 ilm3 3.783 5.303 0.014 0.264 b.d.l. 94.19 25 ilm4_tp b.d.l. 0.128 0.035 0.722 b.d.l. 99.45 25 ilm5 b.d.l. 0.189 0.039 0.310 b.d.l. 96.73 25 mt2_tp b.d.l. 0.052 0.052 0.115 0.026 99.11 25 mt4 b.d.l. 0.022 0.129 0.329 0.034 99.98 25 mt5 b.d.l. 0.378 b.d.l. 1.575 b.d.l. 91.20 25 mt5-2 b.d.l. 0.111 0.058 0.070 0.018 99.63 25 oliv3_oxide1 b.d.l. 0.006 4.282 0.349 0.042 97.95 25 oliv4_oxide1 b.d.l. 0.031 b.d.l. 0.068 0.046 95.04 29 ilm1 b.d.l. 0.323 0.050 0.549 0.015 98.77 29 ilm2 b.d.l. 0.028 0.123 0.527 0.012 99.73 29 ilm3 b.d.l. 0.102 0.059 0.612 b.d.l. 99.80 29 ilm4 b.d.l. 0.084 0.056 0.497 b.d.l. 97.85 29 mt1 b.d.l. 0.138 0.685 0.429 0.053 98.95 29 mt2_tp b.d.l. 0.040 0.754 0.296 0.055 99.96 29 mt3_tp b.d.l. 0.067 0.359 0.331 0.054 99.69 29 mt4_tp b.d.l. 0.074 0.221 0.321 0.041 99.94 29 oliv3_oxide1 b.d.l. 0.017 1.332 0.462 0.059 100.29 29 oliv4_oxide1 b.d.l. 0.001 0.770 0.346 0.052 100.47 29 oliv4_oxide2 b.d.l. b.d.l. 0.876 0.360 0.048 99.90 33 oliv 1_oxide b.d.l. 0.035 5.400 0.415 0.045 100.01 33 oliv 1_oxide b.d.l. 0.109 0.706 0.414 0.028 99.80 33 oliv 14_oxide b.d.l. 0.176 0.990 0.435 b.d.l. 99.82 33 oliv 14_oxide b.d.l. 0.039 11.099 0.394 0.058 98.46 33 oliv 14_oxide b.d.l. 0.074 1.167 0.442 0.042 99.33 33 oliv 5_oxide b.d.l. 0.250 1.288 0.451 0.032 99.50 33 oliv 5_oxide b.d.l. 0.047 3.245 0.406 0.021 100.07 33 oliv 5_oxide b.d.l. 0.072 3.451 0.426 0.026 99.10 33 oliv 5_oxide b.d.l. 0.076 0.689 0.428 0.019 100.27 33 oliv 5_oxide b.d.l. 0.059 3.731 0.415 0.029 100.10 33 oliv 5_oxide b.d.l. 0.065 3.179 0.418 0.021 99.26 33 oliv 7_ilm 0.020 0.699 0.142 0.428 0.042 98.63 33 oliv 7_oxide b.d.l. 0.017 12.092 0.357 0.097 99.76 33 oliv 7_oxide b.d.l. 0.041 13.246 0.413 0.062 98.54 33 oliv 7_oxide b.d.l. 0.143 8.235 0.455 0.067 98.60 33 oliv 7_oxide b.d.l. 0.078 9.366 0.490 0.103 99.28 33 oliv 7_oxide b.d.l. 0.049 1.739 0.385 0.011 100.88 33 oliv 7_oxide b.d.l. 0.999 0.302 0.343 b.d.l. 101.10 33 oliv 7_oxide b.d.l. 0.150 0.103 0.302 0.018 96.69 33 oliv 7_oxide b.d.l. 0.077 1.374 0.443 0.040 99.76 33_ilm1 0.038 1.092 0.083 0.462 b.d.l. 99.43 33_ilm2 b.d.l. 0.292 0.118 0.659 b.d.l. 96.97 33_ilm3 b.d.l. 0.308 0.045 0.362 b.d.l. 97.90 33_ilm4 b.d.l. 0.232 0.059 0.453 b.d.l. 96.20 33_ilm5 0.032 0.258 0.037 0.621 b.d.l. 97.67 33_ilm6 b.d.l. 0.271 0.133 0.517 b.d.l. 98.60 96

SAMPLE P2O5 CaO Cr2O3 MnO NiO TOTAL 33_mt1 b.d.l. 0.277 0.074 0.373 0.017 98.25 33_mt1-2 b.d.l. 0.206 0.487 0.450 0.025 98.80 33_mt2 b.d.l. 0.197 0.086 0.460 b.d.l. 99.14 33_mt3 b.d.l. 0.252 0.119 0.460 0.028 98.47 33_mt4 b.d.l. 0.214 0.073 0.370 0.022 98.17 33_mt5 b.d.l. 0.197 0.080 0.356 0.021 98.38 33_mt6 b.d.l. 0.186 0.114 0.448 b.d.l. 99.39 36 newsite55_ilm 0.310 0.557 0.006 0.656 b.d.l. 97.36 36 newsite55_mt 0.128 0.369 0.049 0.488 b.d.l. 98.27 36 oliv 14_oxide b.d.l. 0.004 8.258 0.357 0.086 100.23 36 oliv 14_oxide b.d.l. 0.024 2.670 0.358 0.042 100.23 36 oliv 14_oxide b.d.l. 0.065 2.391 0.382 0.025 99.50 36 oliv 14_oxide b.d.l. 0.003 10.335 0.357 0.096 99.35 36 oliv 17_oxide b.d.l. 0.038 13.029 0.358 0.067 99.64 36 oliv 17_oxide b.d.l. 0.009 12.658 0.329 0.104 99.40 36 oliv 17_oxide b.d.l. 0.023 13.246 0.327 0.097 98.94 36 oliv 17_oxide b.d.l. 0.118 2.361 0.389 0.019 99.67 36_ilm2 0.033 0.322 0.022 0.542 b.d.l. 94.50 36_ilm3 b.d.l. 0.262 0.018 0.567 b.d.l. 98.39 36_ilm4 b.d.l. 0.227 0.017 0.600 b.d.l. 98.30 36_ilm5 b.d.l. 0.425 0.014 0.536 b.d.l. 98.77 36_ilm6 b.d.l. 0.204 0.013 0.531 b.d.l. 97.97 36_mt2 0.009 0.225 0.057 0.374 b.d.l. 97.48 36_mt3 b.d.l. 0.285 0.392 0.357 b.d.l. 93.68 36_mt3-2 b.d.l. 0.113 1.853 0.401 b.d.l. 98.87 36_mt4 b.d.l. 0.230 0.154 0.494 b.d.l. 98.00 36_mt5 0.117 0.367 0.059 0.256 b.d.l. 96.58 36_mt5-2 b.d.l. 0.235 0.102 0.348 b.d.l. 99.24 36_mt6 b.d.l. 0.276 0.120 0.406 b.d.l. 97.90 97

Table A7. WUSTL electron microprobe data for spinels (olivine inclusions) within the following samples: MP-17-01, 02, 04, 09, 25, 33, 36. Detection limit was analyzed at 99% confidence level (3σ) (b.d.l.=below detection limit).

SAMPLE Na2O MgO Al2O3 SiO2 TiO2 V2O3 Fe3O4 P2O5 01 oliv 11_oxide b.d.l. 2.927 4.708 b.d.l. 5.787 0.512 69.234 0.015 01 oliv 11_oxide b.d.l. 2.901 4.649 b.d.l. 5.867 0.551 69.717 b.d.l. 01 oliv 11_oxide2 b.d.l. 8.650 16.030 b.d.l. 1.549 0.276 46.096 b.d.l. 01 oliv 11_oxide2 b.d.l. 7.772 15.461 b.d.l. 1.844 0.263 51.783 b.d.l. 01 oliv 11_oxide2 b.d.l. 9.375 21.115 b.d.l. 0.590 0.116 39.598 b.d.l. 01 oliv 11_oxide2 b.d.l. 10.404 24.177 b.d.l. 0.365 0.109 35.221 b.d.l. 01 oliv 6_oxide b.d.l. 5.674 8.807 b.d.l. 3.135 0.278 61.551 b.d.l. 01 oliv 6_oxide b.d.l. 3.429 3.558 b.d.l. 9.283 0.712 76.247 b.d.l. 01 oliv 6_oxide b.d.l. 8.284 15.593 b.d.l. 1.082 0.203 45.685 b.d.l. 01 oliv 6_oxide b.d.l. 2.941 3.139 b.d.l. 10.102 0.740 78.712 0.009 01 oliv 7_oxide b.d.l. 3.314 4.059 b.d.l. 7.267 0.573 74.229 b.d.l. 01 oliv 7_oxide b.d.l. 1.511 2.252 b.d.l. 10.598 0.800 80.346 b.d.l. 01 oliv 7_oxide b.d.l. 10.015 21.026 b.d.l. 0.497 0.124 34.636 b.d.l. 01 oliv 7_oxide b.d.l. 9.338 20.101 b.d.l. 0.586 0.151 38.687 b.d.l. 01 oliv 7_oxide b.d.l. 9.430 20.237 b.d.l. 0.669 0.159 40.120 b.d.l. 01 oliv 7_oxide b.d.l. 10.717 20.479 b.d.l. 1.424 0.283 45.051 b.d.l. 01 oliv 7_oxide b.d.l. 8.486 18.441 b.d.l. 1.806 0.235 52.011 b.d.l. 02 oliv 2_oxide b.d.l. 3.470 5.136 0.078 9.725 0.727 73.259 b.d.l. 02 oliv 3_oxide b.d.l. 4.642 9.952 b.d.l. 3.516 0.370 63.726 b.d.l. 02 oliv 3_oxide b.d.l. 3.408 5.046 b.d.l. 8.965 0.762 73.891 b.d.l. 04 oliv 1_oxide b.d.l. 4.729 7.525 b.d.l. 4.151 0.351 60.488 b.d.l. 04 oliv 1_oxide b.d.l. 3.428 4.943 0.208 5.571 0.460 69.114 b.d.l. 04 oliv 1_oxide b.d.l. 8.608 17.208 b.d.l. 1.680 0.247 47.256 b.d.l. RU MP-17-02 b.d.l. 12.037 28.057 b.d.l. 0.485 0.123 30.260 b.d.l. 04 oliv 5_oxide2 b.d.l. 11.603 26.745 b.d.l. 0.531 0.135 31.072 b.d.l. 04 oliv 6_oxide1 b.d.l. 13.388 29.737 b.d.l. 0.428 0.143 26.347 b.d.l. 04 oliv 6_oxide2 b.d.l. 13.442 30.138 0.124 0.409 0.135 25.744 b.d.l. 09 oliv 1_oxide1 0.072 6.873 15.594 b.d.l. 2.649 0.387 53.667 b.d.l. 09 oliv 3_oxide1 b.d.l. 7.398 16.312 b.d.l. 2.665 0.359 51.560 b.d.l. 09 oliv 4_oxide1 0.025 6.156 12.689 b.d.l. 4.326 0.432 56.449 b.d.l. 09 oliv 5_oxide1 b.d.l. 5.520 10.416 b.d.l. 3.226 0.370 60.467 b.d.l. 09 oliv 5_oxide2 b.d.l. 5.629 12.089 b.d.l. 2.898 0.355 58.178 b.d.l. 25 oliv3_oxide1 b.d.l. 1.199 5.395 b.d.l. 5.170 1.096 80.524 b.d.l. 33 oliv 1_oxide b.d.l. 3.588 3.368 b.d.l. 11.182 0.838 75.279 b.d.l. 33 oliv 14_oxide b.d.l. 3.044 6.693 0.289 3.473 0.522 72.833 b.d.l. 33 oliv 5_oxide b.d.l. 3.004 2.557 b.d.l. 12.492 0.840 77.097 b.d.l. 33 oliv 5_oxide b.d.l. 2.689 2.431 b.d.l. 12.105 0.809 77.202 b.d.l. 33 oliv 5_oxide b.d.l. 2.732 2.435 b.d.l. 12.493 0.843 77.978 b.d.l. 33 oliv 5_oxide b.d.l. 2.701 2.507 0.317 12.284 0.829 76.948 b.d.l. 33 oliv 7_oxide b.d.l. 3.565 2.964 b.d.l. 11.431 1.072 70.337 b.d.l. 33 oliv 7_oxide b.d.l. 3.852 3.442 b.d.l. 12.484 0.897 69.109 b.d.l. 33 oliv 7_oxide b.d.l. 3.705 6.570 0.646 6.912 0.750 66.183 b.d.l. 33 oliv 7_oxide b.d.l. 5.442 11.05 b.d.l. 4.060 0.504 66.236 b.d.l. 98

SAMPLE Na2O MgO Al2O3 SiO2 TiO2 V2O3 Fe3O4 P2O5 36 oliv 14_oxide b.d.l. 3.370 5.373 b.d.l. 4.583 0.464 74.881 b.d.l. 36 oliv 14_oxide b.d.l. 3.975 5.292 b.d.l. 6.060 0.518 75.791 b.d.l. 36 oliv 14_oxide b.d.l. 2.555 3.645 b.d.l. 9.855 0.742 80.453 b.d.l. 36 oliv 14_oxide b.d.l. 2.363 3.633 b.d.l. 9.754 0.709 80.304 b.d.l. 36 oliv 17_oxide b.d.l. 0.979 1.270 b.d.l. 11.683 0.776 82.150 b.d.l. 36 oliv 17_oxide b.d.l. 4.352 10.51 0.453 4.119 0.450 66.271 b.d.l. 36 oliv 17_oxide b.d.l. 6.090 13.62 b.d.l. 3.491 0.461 61.707 b.d.l. 36 oliv 17_oxide b.d.l. 5.952 13.14 b.d.l. 3.713 0.477 63.116 b.d.l. 99

SAMPLE CaO Cr2O3 MnO NiO TOTAL 01 oliv 11_oxide 0.015 16.437 0.377 0.038 99.92 01 oliv 11_oxide 0.020 15.570 0.379 0.034 99.62 01 oliv 11_oxide2 0.012 27.408 0.348 0.092 100.32 01 oliv 11_oxide2 0.006 22.922 0.338 0.092 100.35 01 oliv 11_oxide2 0.018 29.209 0.291 0.141 100.32 01 oliv 11_oxide2 b.d.l. 30.101 0.298 0.104 100.64 01 oliv 6_oxide 0.012 19.806 0.352 0.082 99.54 01 oliv 6_oxide 0.038 6.790 0.379 0.037 100.37 01 oliv 6_oxide 0.000 27.880 0.342 0.131 99.08 01 oliv 6_oxide 0.076 3.976 0.380 0.041 100.05 01 oliv 7_oxide 0.014 10.598 0.383 0.026 100.34 01 oliv 7_oxide 0.037 4.618 0.431 0.012 100.49 01 oliv 7_oxide 0.006 34.174 0.298 0.126 100.75 01 oliv 7_oxide 0.002 31.290 0.309 0.124 100.45 01 oliv 7_oxide 0.002 29.732 0.287 0.130 100.63 01 oliv 7_oxide 0.115 21.695 0.303 0.131 100.05 01 oliv 7_oxide 0.025 19.181 0.329 0.099 100.49 02 oliv 2_oxide 0.018 6.976 0.435 0.055 99.87 02 oliv 3_oxide 0.042 17.410 0.395 0.056 99.96 02 oliv 3_oxide 0.020 7.502 0.432 0.060 99.96 04 oliv 1_oxide 0.041 21.062 0.386 0.057 98.69 04 oliv 1_oxide 0.075 13.004 0.380 0.041 97.23 04 oliv 1_oxide 0.012 23.680 0.326 0.091 99.05 RU MP-17-02 0.004 28.636 0.260 0.152 99.92 04 oliv 5_oxide2 0.003 29.115 0.270 0.132 99.54 04 oliv 6_oxide1 0.006 30.013 0.238 0.176 100.37 04 oliv 6_oxide2 0.010 29.460 0.238 0.184 99.89 09 oliv 1_oxide1 0.027 20.610 0.338 0.102 100.18 09 oliv 3_oxide1 0.011 21.197 0.346 0.095 99.84 09 oliv 4_oxide1 0.006 18.739 0.367 0.085 99.18 09 oliv 5_oxide1 0.012 20.083 0.377 0.056 100.44 09 oliv 5_oxide2 0.014 20.184 0.395 0.062 99.70 25 oliv3_oxide1 0.006 4.282 0.349 0.042 97.95 33 oliv 1_oxide 0.035 5.400 0.415 0.045 100.01 33 oliv 14_oxide 0.039 11.099 0.394 0.058 98.46 33 oliv 5_oxide 0.059 3.731 0.415 0.029 100.10 33 oliv 5_oxide 0.072 3.451 0.426 0.026 99.10 33 oliv 5_oxide 0.047 3.245 0.406 0.021 100.07 33 oliv 5_oxide 0.065 3.179 0.418 0.021 99.26 33 oliv 7_oxide 0.078 9.366 0.490 0.103 99.28 33 oliv 7_oxide 0.143 8.235 0.455 0.067 98.60 33 oliv 7_oxide 0.041 13.246 0.413 0.062 98.54 33 oliv 7_oxide 0.017 12.092 0.357 0.097 99.76 100

SAMPLE CaO Cr2O3 MnO NiO TOTAL 36 oliv 14_oxide 0.003 10.335 0.357 0.096 99.35 36 oliv 14_oxide 0.004 8.258 0.357 0.086 100.23 36 oliv 14_oxide 0.024 2.670 0.358 0.042 100.23 36 oliv 14_oxide 0.065 2.391 0.382 0.025 99.50 36 oliv 17_oxide 0.118 2.361 0.389 0.019 99.67 36 oliv 17_oxide 0.038 13.029 0.067 99.64 36 oliv 17_oxide 0.023 13.246 0.327 0.097 98.94 36 oliv 17_oxide 0.009 12.658 0.329 0.104 99.40 101

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