OSTRACODES AS INDICATORS OF THE PALEOENVIRONMENT IN THE PLIOCENE GLENNS FERRY FORMATION, GLENNS FERRY LAKE, IDAHO A thesis submitted to Kent State University in partial fulfillment of the requirements for the degree of Masters of Science by Cordelia W. Dennison-Budak May, 2010 i Thesis written by Cordelia W. Dennison-Budak B.A., College of Wooster, 2007 M.A., Kent State University, 2010 Approved by ___________________________________, Advisor Dr. Alison J. Smith ___________________________________, Chair, Department of Geology Dr. Daniel Holm ___________________________________, Dean, College of Arts and Sciences Dr. Timothy Moerland ii TABLE OF CONTENTS LIST OF FIGURES………………………………………………………………v LIST OF TABLES………………………………………………………………vii ACKNOWLEDGMENTS ................................................................................... viii ABSTRACT ........................................................................................................... ix INTRODUCTION ...................................................................................................1 BACKGROUND .....................................................................................................5 Location .......................................................................................................5 Regional Geology ......................................................................................10 Western Snake River Plain ............................................................12 Geothermal Influences ...............................................................................17 STRATIGRAPHY .................................................................................................19 Idaho Group ...............................................................................................19 Glenns Ferry Formation .................................................................21 Tuana Gravel ................................................................................. 26 PLIOCENE-PLEISTOCENE LAKES...................................................................27 Black Rock, Utah .......................................................................................27 Bonneville System, Idaho and Utah...........................................................28 Bear Lake, Utah and Idaho ........................................................................31 Beaver Basin, Utah ....................................................................................31 Searles Lake, California .............................................................................32 REGIONAL PALEOECOLOGY OF IDAHO IN THE PLIO-PLEISTOCENE ..35 Pollen .........................................................................................................35 Fish .............................................................................................................43 Ostracodes ..................................................................................................44 METHODS ............................................................................................................46 iii Field Work .................................................................................................46 Lab Work ...................................................................................................47 Isotope Analysis .........................................................................................50 Statistical Analysis .....................................................................................51 Cluster Analysis .............................................................................52 Principal Component Analysis ......................................................53 RESULTS ..............................................................................................................54 Ostracode Assemblages .............................................................................54 Limnocythere robusta Assemblage ................................................59 Limnocythere friabilis Assemblage ...............................................61 Candona crogmaniana Assemblage ..............................................63 Limnocythere ceriotuberosa Assemblage ......................................67 Principal Components Analysis (PCA) .....................................................70 Cluster Analysis .........................................................................................77 Ostracode Zonation and Paleolake Phases .................................................77 Stable Isotopes ...........................................................................................83 DISCUSSION ........................................................................................................88 CONCLUSIONS....................................................................................................91 REFERENCES ......................................................................................................95 iv LIST OF FIGURES Fig. 1. Map of Hagerman Fossil Beds National Monument ...................................6 Fig. 2. Geologic map of Hagerman, Idaho ..............................................................9 Fig. 3. Landslide in Hagerman Fossil Beds NM ...................................................10 Fig. 4. Map of western and eastern Snake River Plains ........................................12 Fig. 5. Stages of Lake Idaho .................................................................................14 Fig. 6. Map of western Snake River Plain ............................................................15 Fig. 7. Stratigraphy of the Idaho Group ................................................................20 Fig. 8. Members of the Glenns Ferry Formation ..................................................23 Fig. 9. Hagerman Fossil Beds NM timeline .........................................................25 Fig. 10. Map of Pleistocene pluvial lakes in the Great Basin ...............................30 Fig. 11. Map of Searles Lake ................................................................................33 Fig. 12. Climatic stages of Searles Lake ...............................................................34 Fig. 13. Pollen chart from the Hagerman Horse Quarry .......................................39 Fig. 14. Mural of Hagerman Fossil Beds NM ......................................................40 Fig. 15. Five pollen groups ...................................................................................42 Fig. 16. Plate of Hagerman Fossil Beds NM ostracodes ......................................57 Fabaeformiscandona rawsoni Limnocythere friabilis Ilyocypris cf. bradyi Limnocythere ceriotuberosa Limnocythere robusta Fig. 17. Limnocythere robusta Assemblage .........................................................60 Fig. 18. Limnocythere friabilis Assemblage .........................................................62 Fig. 19. Candona crogmaniana Assemblage ........................................................66 Fig. 20. Limnocythere ceriotuberosa Assemblage ...............................................69 v Fig. 21. Principal Component Analysis Variables ................................................74 Fig. 22. Principal Component Analysis Scores ....................................................76 Fig. 23. Cluster Analysis .......................................................................................80 Fig. 24. Species vs. Valves/gram of Hagerman Fossil Beds NM ostracodes .......82 Fig. 25. Oxygen isotope 18O vs. Elevation ..........................................................84 Fig. 26. Relative oxygen isotope (18O) and carbon (13C) for Hagerman Fossil Beds NM ostracode species ...................................85 Fig. 27. Oxygen isotope 18O vs. Deuterium ........................................................87 Fig. 28. Hypothetical location of Lake Idaho .......................................................92 vi LIST OF TABLES Table 1. Previous Works Table ...............................................................................7 Table 2. HAFO Species Table ..............................................................................55 Table 3. Limnocythere robusta Assemblage .........................................................59 Table 4. Limnocythere friabilis Assemblage ........................................................61 Table 5. Candona crogmaniana Assemblage .......................................................64 Table 6. Limnocythere ceriotuberosa Assemblage ...............................................68 Table 7. Eigenvalues and Variance of Principal Component Analysis Data ........72 vii ACKNOWLEDGEMENTS ―What is a dinosaur?‖…‖How can I work with one?‖ These were the first two scientific questions I had ever asked. They were answered by my father when I was 5 years old. He said, ―You could become a paleontologist and study them as a career‖. I said, ―Wow‖. Ever since that conversation my life has been driven passionately towards one thing, becoming a paleontologist. I have had the support of teachers, friends, colleagues, and family along the way. And I want to thank everyone for their support. But, given the journey‘s long distinctive path I would like to thank publicly those people who have stood out from the rest. To my parents, Anthony Budak and Jennie Dennison-Budak, and grandparents, David Dennison and Margaret Dennison, for not simply being there,