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Sequence Stratigraphy of the Marginal Marine Facies of the Jurassic

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Sequence Stratigraphy of the Marginal Marine Facies of the Jurassic Sequence Stratigraphy of the Marginal Marine Facies of the Jurassic Sundance Formation, South Dakota and Wyoming: Implications for Controls of Higher-order Cyclicity in a Greenhouse World Karen Elaine Bossenbroek A thesis submitted to the faculty of the University of North Carolina at Chapel Hill in partial fulfillment of the requirements for the degree of Master of Science in the Department of Geological Sciences. Chapel Hill 2011 Approved By: Dr. Louis R. Bartek III Dr. Kevin G. Stewart Dr. Brian W. Horn ©2011 Karen Elaine Bossenbroek ALL RIGHTS RESERVED ii ABSTRACT Karen Elaine Bossenbroek: Sequence Stratigraphy of the Marginal Marine Facies of the Jurassic Sundance Formation, South Dakota and Wyoming: Implications for Controls of Higher-order Cyclicity in a Greenhouse World (under the direction of Dr. Louis R. Bartek III) The Sundance Formation was produced by three marine inundations of the Western Interior during the Mesozoic, and the passive margin sediments are exposed in the Black Hills region of Wyoming and South Dakota. This study applies sequence-stratigraphic principles in correlation of geophysical well-log data and measured outcrops to establish a chronostratigraphic framework, in order to identify possible processes that govern stratigraphic architecture. The Sundance is part of a higher-order trend of marine inundations on the Western Interior governed by 3rd order cyclicity. The stratigraphy of the Lower Sundance displays a long-term trend of transgression and regression, punctuated by multiple parasequences. High-frequency variation in stratal architecture observed was likely shaped by cyclic variation in sediment supply governed by climate change. This study supports the current view that eustacy during greenhouse intervals is governed by low-frequency slow variations, and higher-frequency short-order cyclicity in sedimentation may also be superimposed during these long-term intervals. iii Acknowledgements: Many thanks go to my committee Members, Dr. Lou Bartek, Dr. Kevin Stewart, and Dr. Brian Horn for their encouragement, guidance and oversight of this project. I’d also like to thank the UNC Martin Fund for providing the funding for this project. I would like to thank the South Dakota Department of Environment and Natural Resources Oil and Gas Section for providing well-log data and assistance, along with Mr. Roger Barton of True Oil Company in Casper, WY for providing the cuttings data. Thanks also go out to the land owners in Wyoming and South Dakota who allowed access to their land, especially to Wade Wilkins for his generous accommodation. Thanks to Joe Forrest for his insights and technical support. I would like to thank my family for their support of me during this project, including my parents, Kathleen and James Bossenbroek, my sisters Kristen Bossenbroek and Kelly Fedoriw, my brother-in-law Yuri Fedoriw, and nephew Adrian James and niece Emily Kathleen. Without the support, encouragement, and love of my family I would not have completed this journey, or be where I am today. Words cannot express how much their encouragement and support has meant to me. I would like to thank my fellow graduate students Kristin Walker, Tyson Smith, Jesse Davis and Michael Lester for their constructive criticism, technical support, and insights into this project. Special thanks go to Laura Neser, the best field assistant ever, and Michael Mobilia, the best office-mate ever. iv TABLE OF CONTENTS LIST OF APPENDICES ...................................................................................................................... vii LIST OF FIGURES ............................................................................................................................. viii I. INTRODUCTION .............................................................................................................................. 1 1. Previous Investigations ................................................................................................................... 2 II. GEOLOGIC SETTING ..................................................................................................................... 4 1. Tectonic Setting/Structural Controls .............................................................................................. 4 2. Regional Climate ............................................................................................................................ 6 3. Description of Facies ...................................................................................................................... 7 4. Focus of Study ................................................................................................................................ 8 III. METHODS ....................................................................................................................................... 8 1. Outcrops ......................................................................................................................................... 8 2. Well logs ......................................................................................................................................... 9 3. Cuttings Description ....................................................................................................................... 9 4. Stratigraphically Significant Surfaces ............................................................................................ 9 IV. RESULTS ...................................................................................................................................... 11 1. Facies ............................................................................................................................................ 12 2. Lithostratigraphy and Stratigraphic Architecture ......................................................................... 23 3. Sequence Stratigraphy .................................................................................................................. 26 v V. DISCUSSION .................................................................................................................................. 34 1. Age of the Sundance Formation ................................................................................................... 34 2. Controls on Deposition and Stratigraphic Architecture ............................................................... 35 3. Model of Deposition ..................................................................................................................... 42 4. Interpretation of Facies ................................................................................................................. 43 VI. CONCLUSIONS ............................................................................................................................ 44 VII. REFERENCES ............................................................................................................................. 85 vi LIST OF APPENDICES Appendix 1. Table of Measured Outcrop Sections………………………..…....………….77 Appendix 2. Measured Outcrop Sections descriptions (digital files)..…….…….…………78 Appendix 3. Table of Wells Used in Study…………………………….……....…………..79 Appendix 4. GSA Color Codes………………………………………….….………….…..81 Appendix 5. Table of Facies Descriptions…………………………….…….….….…..…...82 Appendix 6. Table summarizing Diagnostic Characteristics of Systems Tracts….….……84 vii LIST OF FIGURES Figure 1. Map of Sundance and Morrison Formations outcrop in the Black Hills region………………………………………………………………………………..……..46 Figure 2. Generalized Stratigraphy of Jurassic Rocks in the Black Hills area with Fossil Constraints…………………………………………….………………….…………….…..47 Figure 3. Relations between tectonic regime and the Sundance area of deposition, and tectonic elements in the Black Hills region………………………………………………..……..…48 Figure 4. The extent of the early Sundance Sea, and current outcrops of the Sundance Formation in the Black Hills area, Wyoming and South Dakota………..….…………………….……..48 Figure 5. Sundance and Morrison Formation Outcrops, Measured Section Locations, Cuttings Location and Well Locations, Black Hills, South Dakota and Wyoming…………………49 Figure 6. Description of cuttings from Krauss 1 Patented well, Crook County, Wyoming…………………………………………………………………………..….…...50 Figure 7. Example of Parasequences and Higher-Order cyclicity in outcrop……………..…….…51 Figure 8. Example of High-Angle Cross-bedded Sandstone Facies in well log and outcrop……………………………………………………………………………………..52 Figure 9. Example of Flat-Bedded Sandstone Facies in well log and outcrop….………………...53 Figure 10. Example of Mudstone and Limestones facies in well log and outcrop……………..…54 Figure 11. Example of bioturbated and Low-angle Cross-Bedded facies in well log and outcrop……………………………………………………………………..………………55 viii Figure 12. Example of Parallel Planar-Bedded Sandstone Facies in well log and outcrop……………….………………………………………………………………….…..56 Figure 13. Example of Incised Sandstone Facies in outcrop…………………………………...…...57 Figure 14. Example of Redbed Facies in well log and outcrop………………….……………….…58 Figure 15. Example of Belemnite Facies type in well and outcrop…………….…….……………..59 Figure 16. Regional Distribution of the High-Angle Cross-bedded Sandstone Facies in the Black Hills Area……………………………………………………………….…………………………60 Figure 17. Regional Distribution of the Flat-Bedded Sandstone Facies in the Black Hills Area……………………………………………………………………………………..……61 Figure 18. Regional Distribution of the
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