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A Multidisciplinary Palaeoenvironmental Reconstruction of the Campanian Foremost Formation of Southern Alberta

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A Multidisciplinary Palaeoenvironmental Reconstruction of the Campanian Foremost Formation of Southern Alberta A Multidisciplinary Palaeoenvironmental Reconstruction of the Campanian Foremost Formation of Southern Alberta by Michael Glen Wenstob Thompson A thesis submitted to the Faculty of Graduate and Postdoctoral Affairs in partial fulfillment of the requirements for the degree of Master of Science in Earth Sciences Carleton University Ottawa, Ontario © 2018, Michael Glen Wenstob Thompson Abstract The Foremost Formation of southern Alberta, Canada, is the basal member of the Cretaceous (Campanian) Belly River Group, and has been understudied relative to the overlying Oldman and Dinosaur Park formations of this group. Examined outcrop of the upper Foremost Formation preserves coastal estuarine or barrier island/lagoonal environments that transition upward into more inland coastal/ fluvial plain environments during the Claggett marine regression of the Western Interior Seaway. A low abundance, low diversity agglutinated benthic foraminiferal fauna, together with whole rock geochemical proxies, suggests commonly stressed oxygen and salinity conditions in marginal marine environments. Vertebrate microsite faunas display a primarily brackish water environmental influence, with an increase in diversity upsection in conjunction with increased terrestrial deposition. Hadrosaur remains suggest the previously unknown presence of kritosaurs and potentially a basal hadrosauroid, suggesting that the Foremost Formation dinosaur fauna was similarly diverse compared to faunas of well-characterized Campanian formations in North America. ii Acknowledgments My genuine thanks go out to Dr. Claudia Schröder-Adams and Dr. Michael Ryan for giving me the opportunity to work on such an exciting, multidisciplinary project and for their knowledge, advice, and encouragement throughout my time at Carleton University. I’d like to thank Kieran Shepherd and Margaret Currie at the Canadian Museum of Nature and Brandon Strilisky at the Royal Tyrrell Museum for allowing access to their institution’s vertebrate fossil collections and for the assistance they gave me during my research. I thank Dr. David Eberth and Dr. Don Brinkman for doing preliminary sample preparation for my microvertebrate material. I thank the graduate students of Carleton University for their friendship and comradery and the staff and faculty of the Earth Sciences Department for their constant support and hard work. Greg Froude is thanked for always being up for a friendly conversation about our work, birding and everything in between. Thanks goes to Dr. Hillary Maddin and her students, who invited me to many lab meetings, shared insightful advice and information and made me feel very welcome in their group. Special thanks to the Southern Alberta Dinosaur Project 2016 and 2017 field crews for their accommodations and assistance in the field and for making my field experiences some of the best memories I will ever have. Thank you to my committee members, Dr. Jordan Mallon and Dr. Quentin Gall, for their input regarding this thesis and its defense, and thanks to my defense chair Dr. Hanika Rizo for overseeing. My most heartfelt thanks are reserved for my parents, Linda and Murray, my brother Adam, my dog Lexi and the rest of my family and friends for their constant support regarding this degree and everything else I’ve ever wanted to do. iii This research was supporting by an NSERC Discovery Grant awarded to Dr. Schröder-Adams. Field work and conference travel was supported by a Paleontological Society Student Grant and a Dinosaur Research Institute student grant. Accommodations in the field were provided by Dr. Michael Ryan and Dr. David Evans and their funding form the Cleveland Museum of Natural History and the Royal Ontario Museum, respectively, for the Southern Alberta Dinosaur Project. iv Table of Contents Abstract .............................................................................................................................. ii Acknowledgments ............................................................................................................ iii Table of Contents .............................................................................................................. v List of Tables .................................................................................................................... ix List of Figures .................................................................................................................... x List of Appendices ........................................................................................................ xxiv Chapter 1: Introduction ................................................................................................... 1 1.1: Geology and Stratigraphy of the Belly River Group and the Foremost Formation .......................................................................................................................... 7 1.2: Foraminiferal Studies of the Foremost Formation. .............................................. 10 1.3: Geochemical Studies of the Belly River Group..................................................... 11 1.4: Vertebrate Microsite Analyses from the Belly River Group ............................... 12 1.5: Study Area ................................................................................................................ 16 1.6: Materials and Methods ........................................................................................... 22 Chapter 2: Lithostratigraphy ........................................................................................ 33 2.1: Geological Setting .................................................................................................... 33 2.2: Results ....................................................................................................................... 35 2.2.1: Stratigraphic Sections .......................................................................................... 35 2.2.2: Facies Description ................................................................................................. 50 v 2.2.3: Depositional Units of the Foremost Formation .................................................. 64 2.3: Summary .................................................................................................................. 66 Chapter 3: Foraminiferal Assemblages of the Foremost Formation ......................... 70 3.1: Foraminiferal Zonation of the Foremost Formation ............................................ 70 3.2: Results ....................................................................................................................... 73 3.3: Morphogroup Analysis ........................................................................................... 77 3.4: Morphogroups and Palaeoenvironmental Significance of Assemblages ............ 79 3.5: Summary .................................................................................................................. 83 Chapter 4: Whole Rock Geochemistry ......................................................................... 87 4.1: Chemostratigraphic Variations .............................................................................. 88 4.2: Summary .................................................................................................................. 99 Chapter 5: Vertebrate Microsite ................................................................................. 100 5.1: Systematic Palaeontology ...................................................................................... 101 5.2: Results ..................................................................................................................... 122 5.2.1: Taxonomic Abundance....................................................................................... 122 5.2.2: Taphonomic Data for C26 ................................................................................. 130 5.3: Comparison of Vertebrate Microsites from the Foremost Formation with C26 ......................................................................................................................................... 132 5.4: Belly River Group Microsite Assemblage Comparisons.................................... 141 5.5: Dinosaur Abundances of the Belly River Group based on Microsite Data ...... 155 vi 5.6: Dinosaur Assemblages of the Foremost Formation Based on Macrofossils..... 164 5.7: Summary ................................................................................................................ 165 Chapter 6: Hadrosaurs of the Foremost Formation .................................................. 167 6.1: Introduction ........................................................................................................... 167 6.2: Descriptions ............................................................................................................ 175 6.3: Phylogenetic Analyses ........................................................................................... 213 6.4: Results ..................................................................................................................... 214 6.5: Discussion ............................................................................................................... 220 6.6: Conclusion .............................................................................................................. 227 Chapter 7: Interpretations and Discussion................................................................
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