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Evolution and Stratigraphic Architecture of Tidal Point Bars With University of New Orleans ScholarWorks@UNO University of New Orleans Theses and Dissertations Dissertations and Theses Fall 12-20-2019 Evolution and stratigraphic architecture of tidal point bars with and without fluvial input: influence ofariable v flow egimesr on sediment and facies distribution, and lateral accretion Pricilla Souza [email protected] Follow this and additional works at: https://scholarworks.uno.edu/td Part of the Geology Commons, Geomorphology Commons, Geophysics and Seismology Commons, Hydrology Commons, Sedimentology Commons, and the Stratigraphy Commons Recommended Citation Souza, Pricilla, "Evolution and stratigraphic architecture of tidal point bars with and without fluvial input: influence of variable flow egimesr on sediment and facies distribution, and lateral accretion" (2019). University of New Orleans Theses and Dissertations. 2705. https://scholarworks.uno.edu/td/2705 This Dissertation is protected by copyright and/or related rights. It has been brought to you by ScholarWorks@UNO with permission from the rights-holder(s). You are free to use this Dissertation in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/ or on the work itself. This Dissertation has been accepted for inclusion in University of New Orleans Theses and Dissertations by an authorized administrator of ScholarWorks@UNO. For more information, please contact [email protected]. Evolution and stratigraphic architecture of tidal point bars with and without fluvial input: influence of variable flow regimes on sediment and facies distribution, and lateral accretion A Dissertation Submitted to the Graduate Faculty of the University of New Orleans in partial fulfillment of the requirements for the degree of Doctor of Philosophy in Engineering and Applied Science Earth and Environmental Sciences by Pricilla Camões Martins de Souza B.S. Universidade do Estado do Rio de Janeiro, 2008 M.S. Universidade Federal do Rio de Janeiro, 2011 December, 2019 Acknowledgements I would like to express all my gratitude to my advisor, Dr. Ioannis Georgiou, who encouraged me to enroll in the Engineering and Applied Science PhD program and always motivated me during the challenging moments occurred in these past years. His guidance was essential for the execution of this project and for my academic development. I thank the members of my PhD committee, Dr. Alex McCorquodale, Dr. Duncan FitzGerald, Dr. Zoe Hughes, Dr. Nick Howes and Dr. Royhan Gani for the discussions during the defense of the Prospectus and for the suggestions in general. A special thanks to Dr. Zoe Hughes for providing the hydrodynamic data and whose the preliminary studies in the area were fundamentally important for this work and to Dr. Royhan Gani for the valuable support during the interpretation of bioturbation. I would like to thank Shell Exploration and Production for providing the funding for this project and the Geologix Company that provided a license of the GEO software, which was used for the digitalization of the sedimentological logs and it was essential for a more accurate quantitative sedimentological analysis. I thank all the people involved in the field data collection. From UNO: Mike Brown, Dallon Weathers, Phil McCarty, Kevin Trosclair, Mark Kulp and Dillan. From BU: Zoe Hugues, Duncan FitzGerald and Sammy. I also thank the Georgia LTER, specifically Steve Pennings, and OSI for the assistance in the Boomer acquisition. I also thank all faculty members and graduate students which somehow contributed to my successful progress through each step of this journey until this moment. I thank my supervisors and co-workers for understanding the importance of this project for my academic and professional development. Finally, and most importantly, I would like to thank my husband for being such an amazing partner in life, for the constant support and for always pushing me to challenge myself, and to ii my mother, that even with limited financial resources, provided me the best education she could afford, which allowed me to get here. iii Table of Contents List of Figures… .......................................................................................................................vi List of Tables… .......................................................................................................................vii Abstract……….. ...................................................................................................................... viii Chapter 1 - Introduction and Theoretical Concepts .............................................................. 1 1.1 Introduction ....................................................................................................................... 1 1.2 Study Sites ........................................................................................................................ 3 1.2.1 Altamaha River: bi-directional reach and limit of tidal reversals (FMT) ............................................................... 4 1.2.2 Duplin Tidal River: no fluvial influence ................................................................................................................ 5 1.2.3 Sapelo and Julienton Tidal Rivers: no fluvial influence ....................................................................................... 5 1.3 Database and Methods ..................................................................................................... 6 1.3.1 Sedimentological descriptions and analyses (vibracore logging) – Chapters 2 and 3 ........................................ 6 1.3.2 Seismic interpretation and stratigraphic correlation – Chapter 2 ......................................................................... 9 1.3.3 Sedimentary facies classification and analysis – Chapter 3 .............................................................................. 11 1.3.4 Hydrodynamic interpretation and correlation with the sedimentary record - Chapter 4 ..................................... 12 1.4 Theoretical Concepts .......................................................................................................13 1.4.1 Fluvial Marine Transition zone (FMT) ............................................................................................................... 13 1.4.2 Tidal Asymmetry ............................................................................................................................................... 14 1.4.3 Estuarine Turbidity Maximum (ETM) ................................................................................................................. 15 1.4.4 Point bars .......................................................................................................................................................... 17 1.4.4.1 Fluvial point bars ............................................................................................................................................ 17 1.4.4.2 Tidal point bars .............................................................................................................................................. 18 1.4.5 Inclined Heterolithic Stratifications (IHS) ........................................................................................................... 19 1.4.6 Impact of tidal influence on reservoir quality ..................................................................................................... 21 1.4.7 Evolution of the Georgia coastline .................................................................................................................... 22 1.4.8 Preservation of estuarine landforms in face of eustatic sea level changes ....................................................... 24 Chapter 2 - The role of the fluvial input in the sedimentology of point bars in meandering tidal rivers……. ........................................................................................................................27 2.1 Introduction ......................................................................................................................27 2.2 Results…… .......................................................................................................................29 2.2.1 Overall sediment distribution ............................................................................................................................. 29 2.2.2 Lateral sediment distribution ............................................................................................................................. 36 2.2.3 Lateral variations in bar morphology ................................................................................................................. 41 2.2.4 Stratigraphic architecture .................................................................................................................................. 47 2.3 Discussions ......................................................................................................................53 2.3.1 Contrasts in sediment distribution ..................................................................................................................... 53 2.3.1.1 Sand versus mud content and the development of IHS ................................................................................. 53 2.3.1.2
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