University of Arkansas, Fayetteville ScholarWorks@UARK Theses and Dissertations 8-2017 Using Stable Isotope Geochemistry to Determine Changing Paleohydrology and Diagenetic Alteration in the Late Cretaceous Kaiparowits Formation, UT USA Daigo Yamamura University of Arkansas, Fayetteville Follow this and additional works at: http://scholarworks.uark.edu/etd Part of the Geology Commons, Paleobiology Commons, and the Sedimentology Commons Recommended Citation Yamamura, Daigo, "Using Stable Isotope Geochemistry to Determine Changing Paleohydrology and Diagenetic Alteration in the Late Cretaceous Kaiparowits Formation, UT USA" (2017). Theses and Dissertations. 2499. http://scholarworks.uark.edu/etd/2499 This Dissertation is brought to you for free and open access by ScholarWorks@UARK. It has been accepted for inclusion in Theses and Dissertations by an authorized administrator of ScholarWorks@UARK. For more information, please contact [email protected], [email protected]. Using Stable Isotope Geochemistry to Determine Changing Paleohydrology and Diagenetic Alteration in the Late Cretaceous Kaiparowits Formation, UT USA A dissertation submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Geosciences by Daigo Yamamura Montana State University Bachelor of Science in Earth Science, 2008 Montana State University Bachelor of Science in Organismal Biology, 2008 Montana State University Master of Science in Earth Science, 2013 August 2017 University of Arkansas This dissertation is approved for recommendation to the Graduate Council. Dr. Celina A. Suarez Dissertation Director Dr. Phillip D. Hays Dr. Margaret Guccione Committee Member Committee Member Dr. Doy Zachry Dr. Ryan Tian Committee Member Committee Member Abstract The Western Interior Basin of the North America preserves one of the best sedimentary and paleontological records of the Cretaceous in the world. The Upper Cretaceous Kaiparowits Formation is a rapidly deposited fluvial sequence and preserves one of the most complete terrestrial fossil record of the North America. Such a unique deposit provides an opportunity to investigate the interaction between the physical environment and ecology. In an effort to decipher such interaction, stable isotope composition of cements in sedimentary rocks, concretions and vertebrate fossils were analyzed. Despite the difference in facies and sedimentary architecture, the isotope composition does not change significantly at ~110 m from the base of the formation. Among the well- preserved cement samples, stable isotope composition indicates a significant hydrologic change within the informal Middle unit; a 6.37‰ depletion in 13C and 3.30‰ enrichment in 18O occurs at ~300 m above the base of the formation. The isotope values indicate that the sandstone cements below 300 m were precipitated in a mixing zone between marine and terrestrial groundwater, whereas the cements in upper units were precipitated in a terrestrial groundwater. Despite the difference in physical appearance (i.e. color and shape), the isotopic compositions of cements in concretions are similar to well-cemented sandstone bodies in similar stratigraphic positions. Isotope compositions of the host rock are similar to that of mudrock and weathered sandstone, suggesting the origin of cementing fluids for the sandstone and concretions were the same indicating that: 1) the concretions were formed in shallow groundwater and not related to the groundwater migration, or 2) all cements in upper Kaiparowits Formation are precipitated or altered during later stage groundwater migration. 18 18 Average Oc from each taxon show the same trend as the Op stratigraphic change, 18 suggesting Oc is still useful as a paleoclimatic proxy. Compared to other Campanian 18 formations, fossil Op are depleted for their paleolatitude, suggesting the Kaiparowits Plateau had higher input from high-elevation runoff, consistent with other paleoclimatic studies. 18 Estimated Ow ranged between vadose influenced dry season values of -8.88‰ to high elevation runoff values of -13.76‰ suggesting dynamic hydrologic interactions. Copyright © Daigo Yamamura 2017 All Rights Reserved Acknowledgements The permit for fieldwork was issued by BLM; UT-15-033-02-G. Funding for the stable isotope analyses were provided by the University of Arkansas Fulbright College and Office of Sponsored Research as part of start up funds to C. Suarez. The On to the future grant from the Geological Society of America and Graduate School at the University of Arkansas helped attending conferences. I would like to thank Walter Manger, Ron and Doris Keisler, the Liners and the Department of Geoscience at the University of Arkansas for the departmental scholarships for supporting fieldwork. I would like to thank C. Levitt and R. Irmis from the UMNH for providing the GPS coordinates of fossil localities. I would like to thank A. Titus and S. Richardson of BLM, J. Sertich, I. Miller and M. Getty of DMNS and E. Roberts for sharing information about the Kaiparowits Formation. I would like to thank E. Pollock and L. Conaway for assistance in isotope analyses. I would like to thank Joshua Blackstock for hydrological insight. I would like to thank D. De Breaux of Utah Geological Survey and K. Morgan for conference accommodation. Table of Contents Chapter 1: Using stable isotope geochemistry to determine changing paleohydrological and diagenetic alteration in the Late Cretaceous Kaiparowits Formation, UT USA ................. 1 1.1 Introduction ............................................................................................................... 1 1.2 History of Investigation ............................................................................................ 1 1.3 Geologic Setting ....................................................................................................... 3 1.4 Physical Environment ............................................................................................... 4 1.5 Faunal Composition .................................................................................................. 5 1.6 Stable Isotope Geochemistry .................................................................................... 7 1.7 References ............................................................................................................... 11 1.8 Figures .................................................................................................................... 17 Chapter 2: Isotopic Evidence for Sudden Paleohydrologic Change in the Campanian (Upper Cretaceous) Kaiparowits Formation, South-Central Utah ................................................ 25 2.1 Abstract ................................................................................................................... 25 2.2 Introduction ............................................................................................................. 25 2.3 Materials and Methods ............................................................................................ 29 2.4 Results ..................................................................................................................... 35 2.5 Discussion ............................................................................................................... 38 2.6 Conclusion .............................................................................................................. 44 2.7 Acknowledgement .................................................................................................. 45 2.8 References ............................................................................................................... 45 2.9 Tables ...................................................................................................................... 49 2.10 Figures .................................................................................................................. 51 Chapter 3: Geochemical significance of the spheroidal concretions from the Kaiparowits Formation, south-central Utah .......................................................................................... 59 3.1 Abstract ................................................................................................................... 59 3.2 Introduction ............................................................................................................. 60 3.3 Materials and Methods ............................................................................................ 62 3.4 Results ..................................................................................................................... 63 3.5 Discussion ............................................................................................................... 67 3.6 Conclusion .............................................................................................................. 69 3.7 Acknowledgement .................................................................................................. 69 3.8 Reference ................................................................................................................ 70 3.9 Tables ...................................................................................................................... 72 3.10 Figures .................................................................................................................. 73 Chapter 4: Diagenesis of vertebrate skeletal remains of the