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Tectonics and Sedimentation: the Volute Ion, Tectonic Influences and Correlation of the Tanqua and Laingsburg Subbasins, Southwest Karoo Basin, South Africa

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Tectonics and Sedimentation: the Volute Ion, Tectonic Influences and Correlation of the Tanqua and Laingsburg Subbasins, Southwest Karoo Basin, South Africa Louisiana State University LSU Digital Commons LSU Historical Dissertations and Theses Graduate School 1997 Tectonics and Sedimentation: The volutE ion, Tectonic Influences and Correlation of the Tanqua and Laingsburg Subbasins, Southwest Karoo Basin, South Africa. Erik Douglas Scott Louisiana State University and Agricultural & Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_disstheses Recommended Citation Scott, Erik Douglas, "Tectonics and Sedimentation: The vE olution, Tectonic Influences and Correlation of the Tanqua and Laingsburg Subbasins, Southwest Karoo Basin, South Africa." (1997). LSU Historical Dissertations and Theses. 6523. https://digitalcommons.lsu.edu/gradschool_disstheses/6523 This Dissertation is brought to you for free and open access by the Graduate School at LSU Digital Commons. It has been accepted for inclusion in LSU Historical Dissertations and Theses by an authorized administrator of LSU Digital Commons. For more information, please contact [email protected]. INFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly from the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type o f computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overlaps. Each original is also photographed in one exposure and is included in reduced form at the back o f the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6” x 9” black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. UMI A Bell A Howell Information Company 300 North Zeeb Road, Ann Arbor MI 48106-1346 USA 313/761-4700 800/521-0600 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TECTONICS AND SEDIMENTATION: THE EVOLUTION, TECTONIC INFLUENCES AND CORRELATION OF THE TANQUA AND LAINGSBURG SUBBASINS, SOUTHWEST KAROO BASIN, SOUTH AFRICA A Dissertation Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment o f the requirements for the degree of Doctor of Philosophy in The Department of Geology and Geophysics by Erik Douglas Scott B.S., Louisiana State University, 1992 August 1997 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. UMI Number: 9808780 UMI Microform 9808780 Copyright 1997, by UMI Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. UMI 300 North Zeeb Road Ann Arbor, MI 48103 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. ACKNOWLEDGMENTS I would like to thank my major advisor, Dr. Arnold Bouma, for all of his invaluable help, at any time of the day, during my graduate work. I would also like to thank his wife, Leineka Bouma, for her support and encouragement. The assistance of my dissertation committee, Dr. Laurie Anderson, Dr. Darrell Henry, Dr. Gary Byerly, Dr. Joanne Wolcott and Dr. John Wrenn, in their respective fields, is gratefully acknowledged. I would like to thank the rest of the LSU Department of Geology faculty, staff, especially Sara Marchiafava, and my fellow students for their friendship and support during my studies at LSU. I would like to thank Joanie Hagler from the LSU Department of Agronomy for running the ICP-AES analysis, Mary Lee Eggert for helping with a number of the figures, Dr. Barun Sen Gupta for the use of the JMP software program, Wanda La Blanc for help with the chemical preparation of the data, Rick Young for the prepartion of the thin sections, and Dr. Ray Ferrell for his help with the chemical analysis. The assistance of a number of South African geologists, especially Dr. Maarten de Wit and Dr. de Ville Wickens, and the ideas and information they provided, is gratefully acknowledged. The finacial support of the Shell Foundation and of the Gulf Coast Association of Geological Societies towards my education and research is greatly appreciated. I would like to thank my family for their support and encouragement. Above all is my gratitude for my wife, Angela, who has supported me throughout my undergraduate and graduate studies, who I feel is receiving this degree with me. ii Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. TABLE OF CONTENTS ACKNOWLEDGMENTS................................................................................... ii LIST OF TABLES.............................................................................................. vi LIST OF FIGURES............................................................................................ vii ABSTRACT....................................................................................................... xiii CHAPTER ONE: INTRODUCTION................................................................. 1 General Introduction. .............................................................................. 1 Geologic Setting of Study Area. .............................................................. 2 Tectonics and Sedimentation ................................................................... 12 Foreland Basin Sedimentation ...................................................... 12 CHAPTER TWO: CAPE FOLD BELT AND KAROO BASIN: REVIEW 16 Introduction ............................................................................................ 16 Tectonics of Southwestern Gondwana. .................................................... 18 Paleogeography During the Formation and Filling of the Tanqua and Laingsburg Subbasins ...................................................... 23 The Influence of Cape Fold Belt Structures and Events on Sedimentation .................................................................................... 37 CHAPTER THREE: GOALS OF PROJECT AND METHODOLOGY............... 40 Main Goals of Study ................................................................................ 40 Influence of the Cape Fold Belt on Sedimentation. ........................ 40 Sediment Source Areas and Transport Paths .................................. 4 1 Basin Configuration and Depositional Environment ....................... 42 Deposition o f Submarine Fan Systems .......................................... 43 Methods .................................................................................................. 44 Sampling ...................................................................................... 45 Microfossils .................................................................................. 47 Palynology ................................................................................... 49 Geochemistry .............................................................................. 50 Petrography and Microprobe Analysis .......................................... 51 CHAPTER FOUR: SUBBASIN DEPOSITS..................................................... 52 Introduction ............................................................................................ 52 Tanqua Subbasin ..................................................................................... 54 Tanqua Submarine Fan Complex. ................................................. 56 Lithofacies o f the Tanqua Submarine Fan Complex. ...................... 64 Laingsburg Subbasin ................................................................................ 67 Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. Laingsburg Submarine Fan Complex. ........................................... 69 Lithofacies of the Laingsburg Submarine Fan Complex. ................ 72 Depositional Environment .......................................................................... 73 Trace Fossils............................................................................................ 75 Trace Fossils of the Tanqua and Laingsburg Subbasins ................. 77 Water Conditions ..................................................................................... 88 Water Depth ............................................................................................ 89 CHAPTER FIVE: CORRELATION OF THE DEPOSITS OF THE TANQUA AND LAINGSBURG SUBBASINS................... 94 Introduction. .............................................................................................. 94 Traditional Methods of Correlation ............................................................ 94 Chemostratigraphy
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