Sedimentology and Stratigraphy of the Upper Cretaceous-Paleocene El
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Louisiana State University LSU Digital Commons LSU Master's Theses Graduate School 2002 Sedimentology and stratigraphy of the Upper Cretaceous-Paleocene El Molino Formation, Eastern Cordillera and Altiplano, Central Andes, Bolivia: implications for the tectonic development of the Central Andes Richard John Fink Louisiana State University and Agricultural and Mechanical College Follow this and additional works at: https://digitalcommons.lsu.edu/gradschool_theses Part of the Earth Sciences Commons Recommended Citation Fink, Richard John, "Sedimentology and stratigraphy of the Upper Cretaceous-Paleocene El Molino Formation, Eastern Cordillera and Altiplano, Central Andes, Bolivia: implications for the tectonic development of the Central Andes" (2002). LSU Master's Theses. 3925. https://digitalcommons.lsu.edu/gradschool_theses/3925 This Thesis 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 Master's Theses by an authorized graduate school editor of LSU Digital Commons. For more information, please contact [email protected]. SEDIMENTOLOGY AND STRATIGRAPHY OF THE UPPER CRETACEOUS- PALEOCENE EL MOLINO FORMATION, EASTERN CORDILLERA AND ALTIPLANO, CENTRAL ANDES, BOLIVIA: IMPLICATIONS FOR THE TECTONIC DEVELOPMENT OF THE CENTRAL ANDES A Thesis Submitted to the Graduate Faculty of the Louisiana State University and Agricultural and Mechanical College in partial fulfillment of the requirements for the degree of Master of Science in The Department of Geology and Geophysics by Richard John Fink B.S., Montana State University, 1999 August 2002 ACKNOWLEDGEMENTS I would like to thank Drs. Bouma, Ellwood and Byerly for allowing me to present and defend my M.S. thesis in the absence of my original advisor. Drs. Brian Horton (University of California, Los Angeles) and William Devlin (ExxonMobil Exploration) were instrumental in my development as a scientist and critical thinker. I would like to thank Brian Hampton for providing valuable advice and commentary at all stages of this project. Brian Lareau supplied additional remarks during the project development and analysis phases of this thesis. I am immensely thankful to Dr. Sohrab Tawackoli of the Servicio de Geologia y Minas de Bolivia (La Paz) for logistical support and advice in support of fieldwork. Pedro Chuvata was extremely helpful as a driver, liason and field assistant. James Graber also provided valuable assistance with fieldwork. Conoco Inc. provided petrographic laboratory support. This research was supported by National Science Foundation funds awarded to Dr. Brian Horton. Additional funding was provided by the Geological Society of America, American Association of Petroleum Geologists and Sigma Xi national grants- in-aid programs. Lastly, I would like to thank my parents, Henry J. Fink Jr. and Ilse R. Fink, and Bruce Miller for moral support and encouragement. ii TABLE OF CONTENTS ACKNOWLEDGEMENTS..............................................................................................ii LIST OF TABLES............................................................................................................ v LIST OF FIGURES .........................................................................................................vi ABSTRACT...................................................................................................................viii 1. INTRODUCTION ........................................................................................................ 1 1.1 Tectonic Overview................................................................................................ 2 1.2 Upper Triassic(?)-Paleogene Stratigraphic Overview .......................................... 5 1.2.1 Lower Succession Strata.............................................................................. 5 1.2.2 Middle Succession Strata............................................................................. 5 1.2.3 Upper Succession Strata ............................................................................ 10 2. CRITERIA FOR DISTINGUISHING TECTONIC SETTING ................................. 13 2.1 Rift Basin Systems.............................................................................................. 13 2.1.1 Rift Basin Evolution .................................................................................. 13 2.1.2 Syn-Rift Recognition Criteria........................................................................ 16 2.1.3 Post-Rift Basin Recognition Criteria ......................................................... 19 2.2 Retroarc Foreland Basin Systems ....................................................................... 19 2.2.1 Foreland Basin System Evolution.............................................................. 19 2.2.2 Foreland Basin Recognition Criteria ......................................................... 22 3. EL MOLINO FORMATION...................................................................................... 26 3.1 General Description ............................................................................................ 26 3.1.1 Regional Correlations ................................................................................ 29 3.1.2 Age Control................................................................................................ 30 3.1.3 Depositional Environment-Previous Work................................................ 30 3.2 Depositional Environment-This Work................................................................ 32 3.2.1 FA1 Open Water Facies............................................................................. 32 3.2.2 FA2: Nearshore Facies............................................................................... 41 3.2.3 FA3 Beach, Bar and Shoal Facies.............................................................. 49 3.2.4 FA4: Floodplain Facies.............................................................................. 55 3.2.5 FA5: Fluvial Facies.................................................................................... 62 3.3 Discussion........................................................................................................... 68 4. PALEOCURRENT DIRECTIONS AND PROVENANCE....................................... 72 4.1 Methods and Background Data........................................................................... 72 4.2 Description.......................................................................................................... 76 4.3 Interpretation....................................................................................................... 81 4.4 Discussion........................................................................................................... 82 5. CONCLUSIONS......................................................................................................... 85 iii REFERENCES ............................................................................................................... 89 APPENDIX A. STRATIGRAPHIC SECTIONS ......................................................... 101 APPENDIX B. STRATIGRAPHIC SECTION COORDINATES AND NOTES....... 112 VITA............................................................................................................................. 116 iv LIST OF TABLES 2-1 Recognition criteria for syn-rift, post-rift and foreland basin settings .................. 14 3-1 Table showing lithofacies codes used in subsequent stratigraphic columns......... 36 4-1 Table showing point count parameters.................................................................. 74 4-2 Table showing raw thin section point count data .................................................. 75 4-3 Table showing raw clast count data....................................................................... 77 v LIST OF FIGURES 1-1 Digital elevation and schematic maps showing the field area................................. 3 1-2 Cross-sectional diagram of the Central Andes ........................................................ 4 1-3 Chronostratigraphic column showing Cretaceous Bolivia strata ............................ 6 1-4 Photo of La Puerta Formation ................................................................................. 7 1-5 Photo showing eolian cross-bedding within the La Puerta Formation.................... 8 1-6 Photo showing igneous intrusion within the La Puerta Formation ......................... 9 1-7 Photo of middle succession strata at the Miraflores Syncline............................... 11 1-8 Photo of the Chaunaca and El Molino Formations................................................ 12 2-1 Illustration showing the evolution of active and passive rifts ............................... 15 2-2 Illustration showing the key components of a foreland basin system ................... 21 3-1 Photo showing silicified gastropods used for stratigraphic correlations ............... 27 3-2 Close-up photograph of silicified gastropods........................................................ 28 3-3 Base map showing the location of stratigraphic sections...................................... 33 3-4 Graphic representation of FA1 .............................................................................. 34 3-5 Legend for stratigraphic columns.......................................................................... 35 3-6 Regional distribution of FA1................................................................................