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A Study of the Lithological and Petrographical Changes Across The Florida State University Libraries Electronic Theses, Treatises and Dissertations The Graduate School 2015 A Study of the Lithological and Petrographical Changes Across the Eocene- Oligocene Transition of the Ocala and Suwannee Formations in Northern Florida and Southern Georiga Kayla Smith Follow this and additional works at the FSU Digital Library. For more information, please contact [email protected] FLORIDA STATE UNIVERSITY COLLEGE OF ARTS AND SCIENCES A STUDY OF THE LITHOLOGICAL AND PETROGRAPHICAL CHANGES ACROSS THE EOCENE-OLIGOCENE TRANSITION OF THE OCALA AND SUWANNEE FORMATIONS IN NORTHERN FLORIDA AND SOUTHERN GEORIGA By KAYLA SMITH A Thesis submitted to the Department of Earth, Ocean, & Atmospheric Science in partial fulfillment of the requirements for the degree of Master of Science 2015 Kayla Smith defended this thesis on June 24, 2015. The members of the supervisory committee were: William Parker Professor Directing Thesis Stephen Kish Committee Member James Tull Committee Member The Graduate School as has verified and approved the above-named committee members, and certifies that thesis has been approved with accordance with university requirements. ii I dedicate this thesis to my parents and friends. Without their encouragement, I would have never embarked on this journey. iii AKNOWLEDGMENTS I would like to thank my committee for all the help and support they gave on my endeavors. Dr. William Parker, my major professor, was invaluable in helping me obtain materials and funding for this project as well as giving me the proper guidance needed to complete my research. Without him I could not have finished this work. Dr. Stephen Kish was always willing to lend a helping hand and exceedingly patient with me. Dr. James Tull was helpful in reviewing my manuscript and providing helpful information. Frank Rupert at Florida's Department of Environmental Protection was kind enough to help identify fossils in my samples. To all those that encouraged me to push through in my research, thank you. iv TABLE OF CONTENTS List of Tables.................................................................................................................................vii List of Figures...............................................................................................................................viii Abstract............................................................................................................................................x 1. INTRODUCTION......................................................................................................................1 1.1 Introduction..........................................................................................................................1 1.2 Objectives............................................................................................................................3 1.3 Area of Study.......................................................................................................................3 1.4 Background..........................................................................................................................4 1.5 Lithologic Units...................................................................................................................9 1.5.1 Avon Park Formation................................................................................................9 1.5.2 Ocala Limestone.......................................................................................................9 1.5.3 Bumpnose................................................................................................................10 1.5.4 Residuum on Eocene Sediments.............................................................................10 1.5.5 Suwannee Limestone..............................................................................................10 1.5.6 Undifferentiated Lower Oligocene Sediments........................................................11 2. METHODS...............................................................................................................................12 2.1 Methods..............................................................................................................................12 3. RESULTS..................................................................................................................................14 3.1 Ocala Limestone................................................................................................................14 3.2 Bumpnose Member of the Ocala Limestone.....................................................................14 3.3 Marianna Limestone..........................................................................................................14 3.4 Suwanee Limestone...........................................................................................................15 4. INFERRED DEPOSITIONAL ENVIRONMENTS.................................................................25 4.1 Ocala Limestone................................................................................................................25 4.2 Suwannee Limestone.........................................................................................................27 5. DIAGENESIS...........................................................................................................................29 5.1 Dissolution.........................................................................................................................29 5.2 Calcite Cement...................................................................................................................30 5.3 Dolomitization...................................................................................................................32 5.4 Dolomite Cement...............................................................................................................34 5.5 Chert Precipitation.............................................................................................................35 6. CHANGES ACROSS THE EOCENE-OLIGOCENE BOUNDARY......................................37 v 6.1 Changes Across the Eocene-Oligocene Boundary.............................................................37 7. SPECULATIONS ABOUT THE GULF TROUGH.................................................................39 7.1 Speculations About The Gulf Trough................................................................................39 8. DISCUSSION AND CONCLUSIONS.....................................................................................41 8.1 Discussion and Conclusions..............................................................................................41 References......................................................................................................................................44 Biographical Sketch.......................................................................................................................51 vi LIST OF TABLES 1 Modified from May (1977) and Schmidt (1983).......................................................................8 2 Table of wells used in this study throughout Florida and Georgia. Georgia elevations and total well depths are missing due to lost records after the disembodiment of the Georgia Geological Survey....................................................................................................................13 vii LIST OF FIGURES 1 Stratigraphic column showing the lithostratigraphic units from the Eocene to the Oligocene throughout the Panhandle of Florida (Modified from Braunstein et al., 1988).........................2 2 Area of study..............................................................................................................................4 3 Major physiographic features of Georgia's and Florida's Coastal Plain. Modified from Scott (2001).........................................................................................................................................6 4 Interpretation of the axis of low area by various authors (Schmidt, 1983). a. Applin (1951), Chen (1965), Pontigo (1982). b. Herrick and Vorhis (1963), Cramer (1974), Arden (1974). c. Toulmin (1952), Weaver and Beck (1977), May (1977). d. Chen (1965). e. Applin and Applin (1944, 1967), Hull (1962). f. Applin and Applin (1967). g. Chen (1965).................................9 5 These cross-sections show the textures at the Eocene-Oligocene Boundary in Florida between the Bump Nose Member of the Ocala Limestone in Jackson County and between the Ocala Limestone and Suwannee Limestone in Leon, Madison, and Suwannee counties.......16 6 These cross-sections show the Eocene-Oligocene Boundary between the Ocala Limestone and Suwannee Limestone throughout Colquitt, Thomas, and Brooks counties in Georgia. Elevation data is unknown.......................................................................................................17 7 Depth from top of core versus Percent Porosity for Jackson County, FL. Red line depicts Eocene-Oligocene Boundary. Error bars represent up to 12% error. ......................................18 8 Depth from top of core versus Percent Porosity for Leon County, FL. Red line depicts Eocene-Oligocene Boundary. Error bars represent up to 12% error. ......................................19 9 Depth from top of core versus Percent Porosity for Madison County, FL Red line depicts Eocene-Oligocene
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