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UC Santa Cruz UC Santa Cruz Electronic Theses and Dissertations UC Santa Cruz UC Santa Cruz Electronic Theses and Dissertations Title Investigations of fault zone behavior during earthquake cycles using hydrology and geodesy Permalink https://escholarship.org/uc/item/90p323z6 Author Xue, Lian Publication Date 2015 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA SANTA CRUZ Investigations of fault zone behavior during earthquake cycles using hydrology and geodesy A dissertation submitted in partial satisfaction of the requirements of the degree of DOCTOR OF PHILOSOPHY in EARTH SCIENCES with an emphasis in GEOPHYSICS by Lian Xue September 2015 The Dissertation of Lian Xue is approved: _________________________________ Professor Emily Brodsky, Chair _________________________________ Professor Susan Schwartz _________________________________ Professor Thorne Lay _________________________________ Professor Andrew Fisher _________________________________ Tyrus Miller Vice Provost and Dean of Graduate Studies Copyright © by Lian Xue All rights reserved Table of Contents List of figures ............................................................................................................. VI Abstract ................................................................................................................... VIII Acknowledgments ...................................................................................................... X Introduction ................................................................................................................. 1 Chapter 1. Interseismic megathrust coupling beneath the Nicoya Peninsula, Costa Rica, from the joint inversion of InSAR and GPS data................................ 7 1-1 Introduction ................................................................................................................... 8 1-2 InSAR data and analysis ............................................................................................... 12 1-3 GPS data ....................................................................................................................... 22 1-4 Modeling ....................................................................................................................... 22 1-5 Discussion ..................................................................................................................... 32 1-6 Conclusions .................................................................................................................. 40 1-7 Acknowledgements ....................................................................................................... 41 1-8 References .................................................................................................................... 42 Appendix 1-A: Synthetic Interferogram ............................................................................. 48 Appendix 1-B: Downsampled linear rate map .................................................................... 48 Appendix 1-C: Interseimic coupling model including both strike and dip components ..... 50 Appendix 1-D: Tremor distribution .................................................................................... 54 Appendix 1-E: Stratified atmospheric signal ...................................................................... 55 Appendix 1-F: Uncertainties of the preferred coupling model ........................................... 56 Appendix 1-G: Checkerboard test of InSAR/GPS integrated and GPS only models ......... 58 Chapter 2. Long-term temperature records following the Mw 7.9 Wenchuan (China) earthquake are consistent with low friction ............................................. 60 2-1 Introduction .................................................................................................................. 61 2-2 Methods and Strategy ................................................................................................... 62 2-3 Thermal Observations ................................................................................................... 67 2-4 Analysis of Thermal Anomalies ................................................................................... 70 2-5 Conclusions .................................................................................................................. 74 2-6 Acknowledgments ........................................................................................................ 75 III 2-7 References .................................................................................................................... 75 Appendix 2-A: Profile Alignment ...................................................................................... 78 Appendix 2-B: Thermal Conductivity ................................................................................ 81 Appendix 2-C: Frictional Heat Model ................................................................................ 88 Appendix 2-D: The Drilling Anomaly ................................................................................ 90 Appendix 2-E: Temperature Increase ................................................................................. 92 Chapter 3. Continuous Permeability Measurements Record Healing inside the Wenchuan Earthquake Fault Zone ......................................................................... 96 3-1 Introduction .................................................................................................................. 97 3-2 Hydrological Observations ........................................................................................... 98 3-3 Method ........................................................................................................................ 101 3-4 Results ........................................................................................................................ 105 3-5 Discussion ................................................................................................................... 109 3-6 Conclusions ................................................................................................................ 112 3-7 Acknowledgments ...................................................................................................... 113 3-8 References .................................................................................................................. 113 Appendix 3-A: Hydrologic context .................................................................................. 116 Appendix 3-B: The limitations of the flow model ............................................................ 116 Appendix 3-C: Temporal changes in permeability ........................................................... 118 Appendix 3-D: Advective flow ......................................................................................... 120 Chapter 4. Numerical Tidal Response of Water Level in Anisotropic Homogeneous Media ............................................................................................... 125 4-1 Introduction ................................................................................................................ 126 4-2 Governing Equations .................................................................................................. 127 4-3 Solutions ..................................................................................................................... 130 4-4 Case Study .................................................................................................................. 134 4-5 Discussion ................................................................................................................... 136 4-6 Conclusions ................................................................................................................ 139 4.7 Acknowledgments....................................................................................................... 139 4.7 References ................................................................................................................... 142 Appendix 4-A: Analytical solutions of a horizontally anisotropic flow ........................... 143 IV Appendix 4-B: Analytical solution of a 1D linear flow .................................................... 150 Appendix 4-C: Independence of domain size in numerical models ................................. 151 Chapter 5. Hydrogeologic Architecture of the San Andreas Fault near the Logan Quarry ...................................................................................................................... 156 5-1 Introduction ................................................................................................................ 157 5-2 Tectonic background .................................................................................................. 158 5-3 Observations ............................................................................................................... 160 5-4 Methods ...................................................................................................................... 162 5-5 Results ........................................................................................................................ 169 5-6 Discussion ................................................................................................................... 177 5-7 Conclusions ...............................................................................................................
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