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Chemical and Isotopic Studies of Monogenetic Volcanic Fields: Implications for Petrogenesis and Mantle Source Heterogeneity

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Chemical and Isotopic Studies of Monogenetic Volcanic Fields: Implications for Petrogenesis and Mantle Source Heterogeneity MIAMI UNIVERSITY The Graduate School Certificate for Approving the Dissertation We hereby approve the Dissertation of Christine Rasoazanamparany Candidate for the Degree DOCTOR OF PHILOSOPHY ______________________________________ Elisabeth Widom, Director ______________________________________ William K. Hart, Reader ______________________________________ Mike R. Brudzinski, Reader ______________________________________ Marie-Noelle Guilbaud, Reader ______________________________________ Hong Wang, Graduate School Representative ABSTRACT CHEMICAL AND ISOTOPIC STUDIES OF MONOGENETIC VOLCANIC FIELDS: IMPLICATIONS FOR PETROGENESIS AND MANTLE SOURCE HETEROGENEITY by Christine Rasoazanamparany The primary goal of this dissertation was to investigate the petrogenetic processes operating in young, monogenetic volcanic systems in diverse tectonic settings, through detailed field studies, elemental analysis, and Sr-Nd-Pb-Hf-Os-O isotopic compositions. The targeted study areas include the Lunar Crater Volcanic Field, Nevada, an area of relatively recent volcanism within the Basin and Range province; and the Michoacán and Sierra Chichinautzin Volcanic Fields in the Trans-Mexican Volcanic Belt, which are linked to modern subduction. In these studies, key questions include (1) the role of crustal assimilation vs. mantle source enrichment in producing chemical and isotopic heterogeneity in the eruptive products, (2) the origin of the mantle heterogeneity, and (3) the cause of spatial-temporal variability in the sources of magmatism. In all three studies it was shown that there is significant compositional variability within individual volcanoes and/or across the volcanic field that cannot be attributed to assimilation of crust during magmatic differentiation, but instead is attributed to mantle source heterogeneity. In the first study, which focused on the Lunar Crater Volcanic Field, it was further shown that the mantle heterogeneity is formed by ancient crustal recycling plus contribution from hydrous fluid related to subsequent subduction. The second study focused on the 1759-1774 eruption of Jorullo volcano in the Michoacán-Guanajuato Volcanic Field. There the observed temporal-compositional variation is attributed to a combination of a complex magmatic plumbing system that leads to variable degrees of magmatic fraction, along with concomitant changes in the mantle source over time. The source heterogeneity was produced by a single mantle source fluxed by two distinct subduction components dominated by terrigenous sediment-derived fluid. The third study focused on the origin of closely associated low-Nb, calc-alkaline and high-Nb, alkaline/transitional magmas within the Sierra Chichinautzin Volcanic Field. The low- and high-Nb magmas were shown to be genetically related, with the former produced primarily by addition of sediment-derived hydrous fluid, and the high-Nb magmas generated by melting of pyroxenite-veined mantle formed by sediment melt-mantle reaction. These studies demonstrate the importance of detailed field-based and geochemical analysis of small, monogenetic eruptions for revealing processes of mantle metasomatism and crust-mantle evolution. CHEMICAL AND ISOTOPIC STUDIES OF MONOGENETIC VOLCANIC FIELDS: IMPLICATIONS FOR PETROGENESIS AND MANTLE SOURCE HETEROGENEITY A DISSERTATION Presented to the Faculty of Miami University in partial fulfillment of the requirements for the degree of Doctor of Philosophy Department of Geology & Environmental Earth Science by Christine Rasoazanamparany The Graduate School Miami University Oxford, Ohio 2015 Dissertation Director: Elisabeth Widom, Ph.D. TABLE OF CONTENTS LIST OF TABLES v LIST OF FIGURES vi ACKNOWLEDGMENT viii CHAPTER 1: INTRODUCTION Introduction 1 References 6 CHAPTER 2: ORIGIN OF CHEMICAL AND ISOTOPIC HETEROGENEITY IN A MAFIC, MONOGENETIC VOLCANIC FIELD: A CASE STUDY OF THE LUNAR CRATER VOLCANIC FIELD, NEVADA Abstract 9 Body Text 11 References 32 Appendix 72 CHAPTER 3: TEMPORAL AND COMPOSITIONAL EVOLUTION OF JORULLO VOLCANO, MEXICO: IMPLICATIONS FOR MAGMATIC PROCESSES ASSOCIATED WITH A MONOGENETIC ERUPTION Abstract 76 Body Text 77 References 100 Appendix 139 CHAPTER 4: PETROGENESIS OF MAFIC MAGMAS IN THE SIERRA CHICHINAUTZIN VOLCENIC FIELD, MEXICO: CONSTRAINTS FROM OSMIUM ISOTOPE SYSTEMATICS Abstract 150 iii Body text 151 References 171 Appendix 213 CHAPTER 5: SUMMARY Summary 214 References 219 iv LIST OF TABLES CHAPTER 2: ORIGIN OF CHEMICAL AND ISOTOPIC HETEROGENEITY IN A MAFIC, MONOGENETIC VOLCANIC FIELD: A CASE STUDY OF THE LUNAR CRATER VOLCANIC FIELD, NEVADA 1. Whole rock analyses of the northern LCVF 48 CHAPTER 3: TEMPORAL AND COMPOSITIONAL EVOLUTION OF JORULLO VOLCANO, MEXICO: IMPLICATIONS FOR MAGMATIC PROCESSES ASSOCIATED WITH A MONOGENETIC ERUPTION 1. Major and Trace Element and Isotopic Data 109 CHAPTER 4: PETROGENESIS OF MAFIC MAGMAS IN THE SIERRA CHICHINAUTZIN VOLCENIC FIELD, MEXICO: CONSTRAINTS FROM OSMIUM ISOTOPE SYSTEMATICS 1. Whole Rock Major and Trace Element and Isotopic Data SCVF 183 v LIST OF FIGURES CHAPTER 2: ORIGIN OF CHEMICAL AND ISOTOPIC HETEROGENEITY IN A MAFIC, MONOGENETIC VOLCANIC FIELD: A CASE STUDY OF THE LUNAR CRATER VOLCANIC FIELD, NEVADA 1. Regional Map of the Lunar Crater Volcanic Field 52 2. Major and Trace Element Variation Diagrams 54 3. Primitive Mantle Normalized Trace Element Diagrams 56 4. Strontium-Nd, ƐNd-ƐHf and Sr-Pb Isotopes Diagrams 58 5. Strontium-Nd-Pb Isotope Diagrams 60 6. Osmium Concentrations vs. Os Isotope Diagram, AFC Model 62 7. Osmium Isotope versus Nb/U Diagram 64 8. Lead-Sr and Pb-Os Isotope Diagrams, Mixing Models 66 9. Trace Element Modeling Diagrams 68 10. Cartoon Diagram of Petrogenetic Model 70 CHAPTER 3: TEMPORAL AND COMPOSITIONAL EVOLUTION OF JORULLO VOLCANO, MEXICO: IMPLICATIONS FOR MAGMATIC PROCESSES ASSOCIATED WITH A MONOGENETIC ERUPTION 1. Regional Tectonic Map 113 2. Geologic Map of Jorullo 115 3. MgO versus Eruptive Phase and Relative Stratigraphic Height 117 4. Major Element versus MgO Diagrams 119 5. Trace Element versus MgO Diagrams 121 6. N-MORB Normalized Trace Element Diagrams 123 7. Isotope Variation Diagrams 125 8. Neodymium-Sr and Pb-Sr Isotope Diagrams 127 9. Osmium Isotope versus Ni Diagram 129 10. Strontium-Pb and Nd-Hf Isotope Diagrams, Mixing Models 131 vi 11. Isotopic Models 133 12. Trace Element Models 135 13. Cartoon Diagram of Petrogenetic Model 137 CHAPTER 4: PETROGENESIS OF MAFIC MAGMAS IN THE SIERRA CHICHINAUTZIN VOLCENIC FIELD, MEXICO: CONSTRAINTS FROM OSMIUM ISOTOPE SYSTEMATICS 1. Tectonic Map of the Trans-Mexican Volcanic Belt 185 2. Geologic Map of SCVF 187 3. Major Element versus MgO Diagrams 189 4. Trace Element versus MgO Diagrams 191 5. Trace Element Variation Diagrams 193 6. N-MORB Normalized Trace Element Diagrams 195 7. Isotope Variation Diagrams 197 8. Osmium Isotope versus MgO, Ni, and Os Diagrams 199 9. Osmium-Pb-Sr Isotope versus Ce/Pb and Ba/Zr Diagrams 201 10. Osmium-Pb Isotope Crustal Assimilation Model 203 11. Oxygen Isotope versus Ni 205 12. FC3MS versus MgO Diagram 207 13. Osmium-Pb Isotope Source Mixing Model 209 14. Cartoon Diagram of Petrogenetic Model 211 vii ACKNOWLEDGEMENTS First and foremost, I would like to express my deep sense of gratitude and appreciation to my advisor Dr. Elisabeth Widom for her supervision with invaluable help and advice during my PhD program. I learned a lot from her not only in academia area but in other spheres of life also. I acknowledge the time and energy that she has poured out on my behalf from the very beginning of this study up to the completion of the thesis. Dr. Widom has been an important part of my professional development; and she helped me grow as real scientist. I would like to thank all my committee members: Drs. William K. Hart, Mike Brudzinski, Marie-Noelle Guilbaud and Hong Yang for their valuable input. I would also like to thank the other member of my oral defense committee Dr. Hailiang Dong for his time and insightful questions. This dissertation could not have been completed without the help and contributions from collaborators. I would like to thank Drs. Greg Valentine, Eugene Smith, Claus Siebe, Joaquim Cortés, Mike Spicuzza, John Valley, Sergio Salinas and Marie-Noelle Guilbaud. I would also like to thank Dave Kuentz for his assistance in lab and helped train me on the TIMS. I would also like to thank John Morton for his assistance in the lab. I would also like to thank all of the members of Dr. Elisabeth Widom and William Hart research group for all of the scientific discussions, humors and entertainment during my stay at Miami University. I would like to thank my family for their love, support and encouragement during the final stages of this PhD. Most of all, I thank the almighty God who has given me the strength and courage to carry out this work. Thank you for letting me through all the difficulties. Thank you Lord. This work was supported by the National Science Foundation (NSF EAR#1016042 for Lunar Crater Volcanic Field and EAR#1019798 for Mexico) awarded to Elisabeth Widom, and the Geological Society of America awarded to Christine Rasoazanamparany. viii CHAPTER 1 Introduction Small-volume eruptions (<1 km3) produced by single episodes of volcanic activity, without subsequent eruptions, are referred to as monogenetic volcanoes (Connor and Conway, 2000). Monogenetic volcanoes often occur in high concentrations, comprising monogenetic volcanic fields. Monogenetic volcanoes commonly occur as cinder cones, maars, tuff cones tuff rings, shield volcanoes and lava domes (Valentine and Perry, 2007).
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