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Download PDF 4.24 MB Florida State University Libraries 2015 Gravity Constraints on the Geometry of the Big Bend of the San Andreas Fault in the Southern Carrizo Plains and Pine Mountain Region Ali Can Altintas 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 GRAVITY CONSTRAINTS ON THE GEOMETRY OF THE BIG BEND OF THE SAN ANDREAS FAULT IN THE SOUTHERN CARRIZO PLAINS AND PINE MOUNTAIN REGION By ALI CAN ALTINTAS A Thesis submitted to the Department of Earth, Ocean, and Atmospheric Science in partial fulfillment of the requirements for the degree of Master of Science 2015 Ali Can Altintas defended this thesis on November 9, 2015. The members of the supervisory committee were: David W. Farris Professor Directing Thesis James F. Tull Committee Member Stephen Kish Committee Member The Graduate School has verified and approved the above-named committee members, and certifies that the thesis has been approved in accordance with university requirements. ii ACKNOWLEDGMENTS I have to say that it has been a great two and half year for me in Tallahassee. This city and university taught me a lot more than I thought before I came here. First of all, I would like to thank a lot to my advisor Dr. David Farris. His mentorship and guidance helped me a lot to get my Master’s degree. I would not be the geologist I am today, if it were not for him. Also I want to thank to my committee members Dr. James Tull and Dr. Stephen Kish. They did their best to guide me and I learned a lot from them. Special thanks to Dr. Neil Lundberg, Dr. Yang Wang and Dr. William Parker for being great teachers. I am so grateful for my graduate student friends/colleagues in my department. Since the first day I have felt like I am at home because of them. iii TABLE OF CONTENTS LIST OF FIGURES ...................................................................................................................... vii ABSTRACT ................................................................................................................................... ix CHAPTER 1 INTRODUCTION .....................................................................................................1 1.1. Plate Tectonic Development of the San Andreas Fault ................................................3 1.2. Geologic Settings ..........................................................................................................7 1.2.1. Northern and Central California ....................................................................8 1.2.1.1. Franciscan Rocks ............................................................................8 1.2.1.2. Coast Range Ophiolite ....................................................................9 1.2.1.3. Great Valley Sequence ....................................................................9 1.2.1.4. Salinian Block ...............................................................................10 1.2.2. Southern California ......................................................................................11 1.3. Regional Geology .......................................................................................................13 1.3.1. Northern Transects and Vicinity ..................................................................13 1.3.2. Southern Transects and Vicinity ..................................................................16 CHAPTER 2 FIELD WORK AND DATA PROCESSING ..........................................................17 2.1. Methodology ...............................................................................................................17 2.2. Field Work ..................................................................................................................18 2.3. Data Processing ...........................................................................................................20 2.3.1. Free-Air Correction ......................................................................................20 2.3.2. Simple Bouguer Correction .........................................................................20 2.3.3. Interpolated Terrain Correction ...................................................................20 iv 2.3.4. Spherical Cap Correction .............................................................................21 CHAPTER 3 RESULTS ................................................................................................................23 3.1. Apache Saddle Transect ..............................................................................................23 3.2. Forest Road 27 Transect .............................................................................................26 3.3. Klipstein Canyon Road Transect ................................................................................28 3.4. Elkhorn Grade Road Transect .....................................................................................30 3.5. Data Comparison ........................................................................................................32 CHAPTER 4 STRUCTURAL MODELS ......................................................................................35 4.1. Structural Model A-A’ (Apache Saddle) ....................................................................36 4.2. Structural Model B-B’ (Forest Road 27) ....................................................................37 4.3. Structural Model C-C’ (Klipstein Canyon Road) .......................................................38 4.4. Structural Model D-D’ (Elkhorn Grade Road) ...........................................................39 CHAPTER 5 DISCUSSION ..........................................................................................................42 5.1. Gravity Model Tectonic Implications .........................................................................42 5.2. Gravity Model Hydrocarbon Implications ..................................................................44 CHAPTER 6 CONCLUSIONS .....................................................................................................48 APPENDIX A DENSITY OF COLLECTED ROCK SAMPLES ................................................50 APPENDIX B DATA TABLE OF GRAVITY SURVEY ............................................................52 APPENDIX C PARAMETERS OF STRUCTURAL MODELS ..................................................59 C.1. Parameters of Structural Model A-A’ ........................................................................59 C.2. Parameters of Structural Model B-B’.........................................................................62 C.3. Parameters of Structural Model C-C’.........................................................................65 C.4. Parameters of Structural Model D-D’ ........................................................................70 v REFERENCES ..............................................................................................................................75 BIOGRAPHICAL SKETCH .........................................................................................................79 vi LIST OF FIGURES 1.1. Northeast Pacific Basin ...................................................................................................................... 2 1.2. Diagrams show plate tectonic evolution of the San Andreas Fault ..........................................4 1.3. Geology of California ...............................................................................................................8 1.4. Salton Trough and northern Gulf of California ......................................................................12 2.1. Topography map of the field work area ..................................................................................18 2.2. Bouguer gravity anomaly map of the field work area ............................................................19 2.3. Terrain correction values map of the field work area .............................................................21 3.1. Free-Air anomaly graphic of Apache Saddle Transect ...........................................................24 3.2. Simple Bouguer anomaly graphic of Apache Saddle Transect ..............................................24 3.3. Complete Bouguer anomaly graphic of Apache Saddle Transect ..........................................25 3.4. Free-Air anomaly graphic of Forest Road 27 Transect ..........................................................26 3.5. Simple Bouguer anomaly graphic of Forest Road 27 Transect ..............................................27 3.6. Complete Bouguer anomaly graphic of Forest Road 27 Transect ..........................................28 3.7. Free-Air anomaly graphic of Klipstein Canyon Road Transect .............................................29 3.8. Simple Bouguer anomaly graphic of Klipstein Canyon Road Transect .................................29 3.9. Complete Bouguer anomaly graphic of Klipstein Canyon Road Transect .............................30 3.10. Free-Air anomaly graphic of Elkhorn Grade Road Transect ................................................31 3.11. Simple Bouguer anomaly graphic of Elkhorn Grade Road Transect ...................................32 3.12. Complete Bouguer anomaly graphic of Elkhorn Grade Road Transect ...............................32 3.13. Data comparison for Apache Saddle Transect ......................................................................33
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