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Provenance of the Aptian Mcmurray Formation: Insights from Detrital Zircon Geochronology

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Provenance of the Aptian Mcmurray Formation: Insights from Detrital Zircon Geochronology University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2014-05-02 Provenance of the Aptian McMurray Formation: Insights from Detrital Zircon Geochronology Benyon, Christine Benyon, C. (2014). Provenance of the Aptian McMurray Formation: Insights from Detrital Zircon Geochronology (Unpublished master's thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/27472 http://hdl.handle.net/11023/1478 master thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY Provenance of the Aptian McMurray Formation: Insights from Detrital Zircon U-Pb Geochronology by Christine Benyon A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE DEPARTMENT OF GEOSCIENCE CALGARY, ALBERTA APRIL, 2014 © Christine Benyon 2014 Abstract The McMurray Formation of the Athabasca Oil Sands hosts one of the largest hydrocarbon resources on Earth, yet the provenance of the sediment itself remains poorly constrained. As the first detrital zircon provenance study from the oil sands, new uranium-lead (U-Pb) detrital zircon ages provide important insights into Early Cretaceous paleogeography, continental-scale sediment transport, and assist in the correlation of incised valley deposits. 27 samples dated using laser ablation–multicollector–inductively coupled plasma–mass spectrometry (LA-MC-ICP-MS) reveal two sets of three distinct detrital-zircon signatures. Each set is documented and grouped into three chronofacies, interpreted to reflect derivation from the Canadian Shield, the Appalachians, and the Cordilleran orogen. Several hypotheses are presented to answer the question of when and how sediments from eastern North America were transported to western Canada. These data are combined with subsurface correlations and chemostratigraphic data to demonstrate the complexity of valley fills and examine the relationship between different valley deposits. ii Acknowledgements First and foremost, I extend my sincerest gratitude to my supervisor, Dr. Andrew Leier. His enthusiasm, encouragement, sense of humour, and faith in me throughout the past 2.5 years has been invaluable. By taking a chance and accepting me as one of his students, countless doors were opened for me. I was also fortunate to have had Dr. Stephen Hubbard act as a second supervisor on numerous occasions; his help and ideas greatly enhanced this thesis. In addition, I would like to thank Dr. Dale Leckie for his guidance, input, and constant support. This project would not have been possible without the help of: Milovan Fustic for his assistance in getting this project started; Owen Anfinson and Brant Skibsted for their assistance dating zircons in Tucson; Mike Blum and Keegan Raines for helpful discussions; and Caterina Heikkinen for helping with processing. Andrew Webb and Cynthia Hagstrom (Nexen Energy ULC) also deserve a great deal of recognition for their collaboration and input throughout this project. I also wish to express my sincere thanks to my committee members, including Dr. Derald Smith, for the careful review of my thesis. My colleagues in CABS (Paul Durkin, Adam Coderre, Erin Pemberton, Aaron Reimchen, Nick Zajac, Ben Daniels and Heather Bain, among many) are thanked for providing helpful feedback, as well as making lasting memories at AAPG, Willapa Bay, and Fridays at the grad lounge. The help of former grads Ross Kukulski and Dallin Laycock was especially beneficial. Generous funding for this study was provided by Nexen Energy ULC. National Science Foundation grant EAR-0443387 supported the Arizona LaserChron Center, iii which provided much of the technical work involved in the zircon dating. Dr. George Gehrels, Mark Pecha, and Clayton Loehn were a pleasure to learn from. Finally, I would like to thank my mom Barbara, my sister Jennifer, and my boyfriend Kyle for their patience and emotional support throughout this degree. iv Table of Contents Abstract ............................................................................................................................... ii Acknowledgements ............................................................................................................ iii Table of Contents .................................................................................................................v List of Figures and Illustrations ........................................................................................ vii CHAPTER ONE: INTRODUCTION ..................................................................................1 1.1 References ..................................................................................................................3 CHAPTER TWO: PROVENANCE OF THE CRETACEOUS ATHABASCA OIL SANDS, CANADA: IMPLICATIONS FOR CONTINENTAL-SCALE SEDIMENT TRANSPORT ........................................................................................6 2.1 Introduction ................................................................................................................6 2.2 McMurray Formation ................................................................................................8 2.3 Methods .....................................................................................................................9 2.4 Results ......................................................................................................................10 2.5 Interpretation ............................................................................................................10 2.6 Discussion ................................................................................................................14 2.6.1 “Appalachian” Sediment Pathways .................................................................14 2.6.2 Vertical Stratigraphic Variations .....................................................................19 2.7 Conclusions ..............................................................................................................20 2.8 References ................................................................................................................21 CHAPTER THREE: DETRITAL ZIRCON GEOCHRONOLOGY OF THE MCMURRAY FORMATION AND APPLICATIONS FOR STRATIGRAPHIC ANALYSIS ..............................................................................29 3.1 Introduction ..............................................................................................................29 3.2 Background Geology ...............................................................................................33 3.3 Methodology ............................................................................................................35 3.4 Detrital-Zircon Results ............................................................................................37 3.5 Interpretation of Detrital Zircon Ages .....................................................................40 3.5.1 Detrital Zircon Chronofacies ...........................................................................40 3.5.2 Detrital Zircon Provenance ..............................................................................41 3.5.2.1 Populations .............................................................................................41 3.5.2.2 Chronofacies ..........................................................................................43 3.6 Cross-Sections .........................................................................................................45 3.7 Discussion and Analysis ..........................................................................................48 3.7.1 Detrital Zircon Provenance ..............................................................................48 3.7.1.1 Drainage Area Estimates .......................................................................52 3.7.2 Detrital-Zircon Population Characteristics ......................................................55 3.7.3 Chronofacies and Incised Valley Systems ......................................................58 3.7.4 Detrital Zircons and Chemostratigraphy .........................................................59 3.8 Conclusions ..............................................................................................................62 3.9 References ................................................................................................................63 CHAPTER FOUR: CONCLUSIONS................................................................................74 v 4.1 Future Work .............................................................................................................76 4.2 References ................................................................................................................78 APPENDIX A ....................................................................................................................79 APPENDIX B ....................................................................................................................92 vi List of Figures and Illustrations
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