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UNIVERSITY of CALIFORNIA, SAN DIEGO Marine Geophysical Study UNIVERSITY OF CALIFORNIA, SAN DIEGO Marine Geophysical Study of Cyclic Sedimentation and Shallow Sill Intrusion in the Floor of the Central Gulf of California A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in Oceanography by Jared W. Kluesner Committee in Charge: Professor Peter Lonsdale, Chair Professor Paterno Castillo Professor Graham Kent Professor Falko Kuester Professor Michael Tryon Professor Edward Winterer 2011 Copyright Jared Kluesner, 2011 All rights reserved. The Dissertation of Jared W. Kluesner is approved, and it is acceptable in quality and in form for publication on microfilm and electronically: Chair University of California, San Diego 2011 iii To my parents, Tony and Donna Kluesner and my grandfather James Kluesner iv "...Let us go, we said, into the Sea of Cortez, realizing that we become forever a part of it" The Log from the Sea of Cortez John Steinbeck v TABLE OF CONTENTS Signature Page ...................................................................................... iii Dedication.............................................................................................. iv Epigraph ................................................................................................ v Table of Contents .................................................................................. vi List of Figures ........................................................................................ ix Acknowledgments ................................................................................. xii Vita......................................................................................................... xv Abstract ................................................................................................. xvi Chapter 1. Introduction .......................................................................... 1 1.1 High-Resolution Imaging of Rift-To-Drift Processes................... 2 1.2 References ................................................................................ 8 Chapter 2. Influence of Glacial-Interglacial Cyclicity on Sedimentation and Axial Rift Structure in the Southern Trough, Guaymas Basin.................................................................................... 13 2.1 Abstract ...................................................................................... 14 2.2 Introduction................................................................................. 15 2.3 Geophysical Data....................................................................... 19 2.4 Results and Interpretations ........................................................ 20 2.4.1 Seismic Stratigraphy ........................................................... 20 2.4.2 Lithology and Age of the Seismic Stratigraphic Units.......... 22 2.4.3 Record of Tectonic Deformation and Axial Trough Filling ... 31 vi 2.5 Influence of Glacial/Interglacial Cyclicity on Guaymas Basin Sedimentation ............................................................................ 38 2.6 Cyclic Seismic Stratigraphy Elsewhere Along the Gulf of California Plate Boundary........................................................... 44 2.7 Summary of Conclusions ........................................................... 49 2.8 Acknowledgments ...................................................................... 54 2.9 References ................................................................................. 55 Chapter 3. Geological and Hydrological Effects of Young Intrusive Magmatism in the Central and Southern Gulf of California.. 79 3.1 Abstract ...................................................................................... 80 3.2 Introduction................................................................................. 81 3.3 Geological Setting ...................................................................... 86 3.4 Geophysical Data....................................................................... 89 3.5 Results ....................................................................................... 92 3.5.1 Seismic Characteristics of Magmatic Sills........................... 92 3.5.2 Magmatic Sills and Deformation.......................................... 95 3.5.3 Sills Feeding Sills? .............................................................. 105 3.5.4 Buried Lava Flows?............................................................. 106 3.5.5 Sill Geometry and Emplacement Depth .............................. 107 3.5.6 Sill-Driven Hydrothermal Fluid-Flow.................................... 115 3.5.7 Hydrocarbon Generation, Trapping, and Leakage .............. 124 3.6 Comparison with Magma Intrusion Around Other Turbidite- vii Smothered Spreading Centers................................................... 128 3.7 Conclusions................................................................................ 130 3.8 Acknowledgments ...................................................................... 134 3.9 References ................................................................................. 135 Chapter 4. Conclusions ......................................................................... 209 viii LIST OF FIGURES Figure 1.1 Regional Map of Central Gulf of California ........................... 11 Figure 2.1 Topography of Guaymas and Carmen Basins ..................... 63 Figure 2.2 Multibeam Bathymetry of Study Area in Southwestern Guaymas Basin, and the Adjacent Baja California Continental slope.................................................................. 65 Figure 2.3 3D Cutaway of MCS Profile 1 and Multibeam Bathymetry, Crossing the Southern Trough of Guaymas Basin ............... 67 Figure 2.4 MCS Profile 2 ....................................................................... 69 Figure 2.5 Northwestern Sections of MCS Lines 1 and 2 Tied to DSDP Site 478 Drilling Results........................................................ 71 Figure 2.6 Simplified Rift Evolution Model for the Southern Trough in Guaymas Basin .................................................................... 73 Figure 2.7 Detailed Bathymetric Map of Carmen Basin and a Seismic Transit of Carmen axis.......................................................... 75 Figure 2.8 The Turbidite-Accumulating North Pescadero Transform Valley Near its Intersection with the Axial Rift Valley of the North Pescadero Spreading Axis ......................................... 77 Figure 3.1 Topography of Central and Southern Gulf of California........ 147 Figure 3.2 Map of Sedimentary Features in the Central and Southern Gulf of California................................................................... 149 Figure 3.3 Structural Interpretation Map of Central and Southern Gulf of California .......................................................................... 151 Figure 3.4 MCS Profile A ....................................................................... 153 Figure 3.5 MCS Profile B ....................................................................... 155 ix Figure 3.6 MCS Profile C....................................................................... 157 Figure 3.7 MCS Profile D....................................................................... 159 Figure 3.8 MCS Profile E ....................................................................... 161 Figure 3.9 MCS Profile F ....................................................................... 163 Figure 3.10 MCS Profile G..................................................................... 165 Figure 3.11 Bathymetric Map of 3.5 kHz Survey Near Farallon Transform Scarp................................................................. 167 Figure 3.12 3D Grid of the BEKL 3.5 kHz Survey.................................. 169 Figure 3.13 MCS Profiles H and I .......................................................... 171 Figure 3.14 MCS Profile M .................................................................... 173 Figure 3.15 MCS Profile N..................................................................... 175 Figure 3.16 MCS Profile O..................................................................... 177 Figure 3.17 MCS Profile K ..................................................................... 179 Figure 3.18 Plot of Upturned Sill Width vs. Emplacement Depth .......... 181 Figure 3.19 Bathymetric Map Located at the Bend in the Northern Trough of Guaymas Basin.................................................. 183 Figure 3.20 MCS Profile J...................................................................... 185 Figure 3.21 Boundary Element Based Model Panels A, B and C.......... 187 Figure 3.22 Boundary Element Based Model Panels D, E and F.......... 189 Figure 3.23 Sill Emplacement Model Panels A, B, C, D, E, and F ........ 191 Figure 3.24 MCS Profile P ..................................................................... 193 Figure 3.25 MCS Profile H and Analog 3.5 kHz Profile ......................... 195 Figure 3.26 Fluid-Flow Model Panels A, B, C, and D ............................ 197 Figure 3.27 3D Cutaway of MCS Profile M............................................ 199 Figure 3.28 MCS Profile L ..................................................................... 201 x Figure 3.29 Subsection of Profile F ....................................................... 203 Figure 3.30 3.5 kHz Profile Southwest of Carmen Axis......................... 205 Figure 3.31 Multichannel Seismic Reflection
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