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A High-Resolution 3-D Architecture of a Cretaceous Point Bar Using Terrestrial Laser Scanning of Multiple Exposures

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A High-Resolution 3-D Architecture of a Cretaceous Point Bar Using Terrestrial Laser Scanning of Multiple Exposures A HIGH-RESOLUTION 3-D ARCHITECTURE OF A CRETACEOUS POINT BAR USING TERRESTRIAL LASER SCANNING OF MULTIPLE EXPOSURES: A FAR MORE COMPLEX MODEL OF BAR GROWTH AT THE SCALE OF A STEAM CHAMBER THAN PREVIOUSLY THOUGHT by MATTHEW PALMER Presented to the Faculty of the Graduate School of Texas Christian University in Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE IN GEOLOGY TEXAS CHRISTIAN UNIVERSITY AUGUST 2015 ACKNOWLEDGEMENTS There are many people who have been vital to the success of this project. First, I would like to thank my advisor, Dr. John Holbrook for his instructions, insights, and means to accomplish this work. I am also indebted to Tamie Morgan and Xiangiang Xie (PhD) as committee members for this project. I am grateful for the assistance of Alex Torres who made this study enjoyable and also contributed valuable ideas. I am thankful to Lionel and Sally White, Carlos Aiken PhD., Tara Urbanski, and Becky Aguilar from the University of Texas at Dallas for their help in shooting and processing the photo-realistic LiDAR model. Also, collaboration with Stephen Hubbard and Paul Durkin from the University of Calgary was extremely valuable as they are familiar with the field area and provided important insights and guidance. Chris Seibel and colleagues at Nexen provided significant feedback and support. And finally, to Bruce Vanderlou who allowed us full access to the field area through his private property. Most importantly, I would like to thank my family, in particular my wife Chelsea and Daughter Lydia who will always be the reason and inspiration I need to accomplish hard things. ii TABLE OF CONTENTS ACKNOWLEDGEMENTS ....................................................................................................................................ii TABLE OF CONTENTS ...................................................................................................................................... iii LIST OF FIGURES ..............................................................................................................................................v LIST OF TABLES .............................................................................................................................................. vii CHAPTER 1 INTRODUCTION ............................................................................................................................ 1 1.1 AN OVERVIEW OF POINT BAR FORMATION ....................................................................................................... 2 1.2 TYPES OF POINT-BARS.................................................................................................................................. 6 1.2.1 The “Normal” Point Bar ................................................................................................................. 6 1.2.2 The “Normal Muddy” Point Bar ..................................................................................................... 8 1.2.3 The Counter Point Bar .................................................................................................................... 8 1.2.4 The Pseudo Point Bar ..................................................................................................................... 9 1.3 HETEROGENEITY OF POINT BARS .................................................................................................................. 10 1.4 THE “SADLER EFFECT” IN POINT BARS............................................................................................................ 11 1.5 THE BELLY RIVER GROUP ............................................................................................................................ 14 1.5.1 The Foremost Formation.............................................................................................................. 16 1.5.2 The Oldman Formation ................................................................................................................ 16 1.5.3 The Dinosaur Park Formation ...................................................................................................... 17 1.6 HYPOTHESES AND PREDICTIONS ................................................................................................................... 17 CHAPTER 2 METHODS ................................................................................................................................... 19 2.1 LOCATION ............................................................................................................................................... 19 2.2 STRATIGRAPHIC SECTIONS .......................................................................................................................... 21 2.3 LIDAR ACQUISITION ................................................................................................................................... 21 2.4 ARCHITECTURAL-ELEMENT ANALYSIS............................................................................................................. 23 2.5 DRAPE DISTRIBUTION CALCULATIONS ............................................................................................................ 24 CHAPTER 3 RESULTS ..................................................................................................................................... 26 3.1 STRATIGRAPHIC SECTIONS .......................................................................................................................... 26 3.1.1 Point Bar Lithofacies .................................................................................................................... 26 iii 3.1.2 Drape Types ................................................................................................................................. 27 3.1.3 Paleocurrent Measurements ....................................................................................................... 36 3.2 LIDAR MODEL AND ARCHITECTURAL-ELEMENT ANALYSIS ................................................................................... 39 3.3 DRAPE MEASUREMENTS ............................................................................................................................. 50 3.3.1 Area 1 ........................................................................................................................................... 53 3.3.2 Area 2 ........................................................................................................................................... 56 3.3.3 Area 3 ........................................................................................................................................... 61 CHAPTER 4 DISCUSSION ............................................................................................................................... 65 4.1 STRATIGRAPHIC SECTIONS .......................................................................................................................... 65 4.2 ARCHITECTURAL-ELEMENT ANALYSIS............................................................................................................. 65 4.2.1 0 and 1st Order Surfaces ............................................................................................................... 65 4.2.2 2nd Order Surfaces ........................................................................................................................ 66 4.2.3 3rd Order Surfaces ........................................................................................................................ 67 4.2.4 4th Order Surfaces ........................................................................................................................ 67 4.2.5 5th Order Surfaces ........................................................................................................................ 68 4.3 BAR ACCRETION TYPES AND PHASES .............................................................................................................. 68 4.3.1 Fragmentary Bar Phase ............................................................................................................... 68 4.3.2 Heterolithic Bar Abandonment Phase .......................................................................................... 70 4.4 THE “SADLER EFFECT” ............................................................................................................................... 72 4.5 THE EFFECTS OF DRAPING ON STEAM CHAMBER DEVELOPMENT .......................................................................... 72 CHAPTER 5 CONCLUSIONS ............................................................................................................................ 74 REFERENCES .................................................................................................................................................. 75 APPENDIX ...................................................................................................................................................... 79 VITA ABSTRACT iv LIST OF FIGURES FIGURE PAGE 1. Migration due to expansion, translation, and/or rotation ....................................................................... 4 2. Change in velocity vectors and helical flow in meander bends ................................................................ 5 3. Architecture of “Normal” and “Muddy Normal” point bars ..................................................................... 7 4.
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