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HETEROGENEITY, PALEOHYDROLOGY, AND 3D FACIES ARCHITECTURE OF ANCIENT POINT BARS, FERRON SANDSTONE, NOTOM DELTA, SOUTH-CENTRAL UTAH -------------------------------------------- A Thesis Presented to the Faculty of the Department of Earth and Atmospheric Sciences University of Houston -------------------------------------------- In Partial Fulfillment of the Requirements for the Degree Master of Science -------------------------------------------- By Chenliang Wu August 2013 HETEROGENEITY, PALEOHYDROLOGY, AND 3D FACIES ARCHITECTURE OF ANCIENT POINT BARS, FERRON SANDSTONE, NOTOM DELTA, SOUTH-CENTRAL UTAH ____________________________________ Chenliang Wu APPROVED: ____________________________________ Dr. Janok P. Bhattacharya, Advisor ____________________________________ Dr. Shuhab Khan ____________________________________ Dr. Kenneth Abdulah BHP Billiton Petroleum ____________________________________ Dean, College of Natural Sciences and Mathematics II ACKNOWLEDGEMENTS First of all, I would like to thank my family. I thank my parents Xiaojing Wu and Runju Zhang for their endless love and supports through my whole life. I would also like to thank my loving girlfriend Fanjin Meng, who encouraged and helped me to achieve my goals. Her love and knowledge for life brought me to this point. I am also grateful to Fanjin’s parents Lihua Xiao and Yuanlin Meng who supported me and provided me valuable advices. I dedicate this thesis to all of my family. I would like to especially thank my thesis advisor Dr. Janok P. Bhattacharya. I have always felt lucky to be part of his research team. He leads me to the door of scientific research and well prepared me for my future career. He has always been responsible for his students. He guided me patiently with all his knowledge for academia and industry, and even life. His creative thinking and enthusiasm for geology will always encourage me in my future endeavor. I am grateful to my thesis committee member Dr. Kenneth Abdulah and Dr. Shuhab Khan. Their guidance and help provided me chances to greatly improve the quality of my thesis. Particularly I want to thank Dr. Abdulah for the thorough and detailed review of my thesis draft and Dr. Khan for all the training on GPR. I would also like to thank my colleagues Mohammad Ullah (Apu), Ben Browning, Zhiyang Li, Cameron Griffin, Benjamin Hilton, Yangyang Li, and Jianqiao Wang for all the discussions and critiques on my work. I specially thank Mohammad Ullah (Apu), Ben III Browning, and Zhiyang Li for assisting me collecting data in the field. At last, I want to thank Anadarko, BHP Billiton, BP, Chevron, EcoPetrol, ExxonMobil, Inpex, Nexen, Pioneer, and Shell for the generous financial support to the UH QSL consortium. August 2013 Chenliang Wu IV HETEROGENEITY, PALEOHYDROLOGY, AND 3D FACIES ARCHITECTURE OF ANCIENT POINT BARS, FERRON SANDSTONE, NOTOM DELTA, SOUTH-CENTRAL UTAH -------------------------------------------- An Abstract of a Thesis Presented to the Faculty of the Department of Earth and Atmospheric Sciences University of Houston -------------------------------------------- In Partial Fulfillment of the Requirements for the Degree Master of Science -------------------------------------------- By Chenliang Wu July 2013 V ABSTRACT This study examined ancient exhumed channel belts from the Cretaceous Ferron Sandstone, Notom Delta in south-central Utah. Extensive plan view exposures with local vertical cliff exposures allowed documentation of channel belt dimension, migration pattern (translation versus expansion) and facies architectures. The cliff exposures allow documentation of channel fill thickness and bedding structure that were used in paleogeographic and paleohydraulic reconstructions. Paleocurrent measurements are consistent within one depositional unit (such as a unit bar or channel belt) and can be used to infer channel flow and bar migration patterns. Four hundred and eight paleocurrent directions were integrated with grain-size measurements to reconstruct the 3D facies architecture of the ancient channel belts. Based on the presence of distinct types of inclined strata of large scale foresets and the channel sinuosity (1.01-1.44.) measured from the paleographic map, the formative river of the point bar complex was interpreted to be a low sinuosity river. The point bar complex consists of four successive component point bars and shows a migration pattern that changes from expansion to translation with increasing sinuosity. By using empirical equations, average channel depth and channel width were determined to be 1.7m-3.6m and 23m-89m respectively. Channel width (around 50m) as measured from abandoned channel lags falls into this range. The large variation of channel belt width may be a result of increasing channel dimension due to increasing sinuosity. Therefore, empirical equations for calculating VI paleohydraulic parameters are generally applicable but need further refinement for specific river types. Bar thickness measured from vertical outcrops range from 5.4m to 6.3m which gives a much narrower range of 47 to 59 m for the channel width estimation. The discharge of the formative river is estimated to be 115 m3/sec to 387 m3/sec. Grain-size variation shows a distinct coarsening trend from inner bar to outer bar at both the scale of individual point bars and the meander loop complex. Because of the absence of extensive shale drapes between each point bar, petrophysical heterogeneity introduced by grain-size variation of sand and directional permeability anisotropy introduced by different types of cross bedding will be the main type of heterogeneity. The grain-size distribution shows a more complicated pattern compared to previous models and the resulting fluid flow pattern is expected to be more complex as well. Finally, the major controls on the formation of low sinuosity river are gradient, sediment supply, and bank erosion, although high frequency climate changes are interpreted to be responsible for the filling of the whole incised valley system. The fluvial style is a bed-load to mixed-load, high net-to-gross river system with limited suspended content in the flow. VII TABLE OF CONTENT CHAPTER 1 INTRODUCTION.................................................................. 1 1.1 Previous work on meandering rivers and point bars ........................................................... 1 1.2 Geological setting..................................................................................................................... 3 1.3 Study area and methodology .................................................................................................. 7 CHAPTER 2 ARCHITECTURE OF THE CHANNEL BELT ............... 12 2.1 Lithofacies description .......................................................................................................... 12 2.2 Bedding architecture ............................................................................................................. 23 2.3 Plan view facies architecture ................................................................................................ 36 2.4 Paleogeography...................................................................................................................... 40 2.5 Discussion on the facies architecture of the channel belt ................................................... 43 CHAPTER 3 HETEROGENEITY ............................................................ 44 3.1 Lithological heterogeneity .................................................................................................... 44 3.2 Petrophysical heterogeneity .................................................................................................. 45 CHAPTER 4 PALEOHYDROLOGY ....................................................... 50 4.1 Overview on empirical equations ......................................................................................... 50 4.2 Dimension of the channel ...................................................................................................... 51 CHAPTER 5 DISCUSSION ....................................................................... 55 5.1 Evolution of the channel bend .............................................................................................. 55 5.2 Fluvial style and controls ...................................................................................................... 58 VIII CHAPTER 6 CONCLUSIONS .................................................................. 59 REFERENCES ............................................................................................ 61 APPENDIX ................................................................................................... 74 IX CHAPTER 1 INTRODUCTION 1.1 Previous work on meandering rivers and point bars Meandering river studies encompass a variety of fields such as geomorphology, fluid mechanics, river engineering, ecology and sedimentology (Güneralp et al., 2012). Geologists’ concerns are related to meandering channel formation and evolution mechanics (Schumm and Khan, 1972; Hickin, 1974; Jin and Schumm, 1986; Smith, 1998; Peakall et al., 2007; Duan and Julien, 2010), architecture of ancient meander belts (Willis, 1993a; Li et al., 2010), characteristics of associated deposits of meandering rivers (McGowen and Garner, 1970; Ghazi and Mountney, 2009), and the development of fluvial facies models (Galloway and Hobday, 1996; Bridge, 2006). Research on meandering rivers is carried out through flume tests (Schumm and