Preface ........................................................ xi
Foreword ..................................................... xiii
List of Contributors ........................................... xv
1. Introduction: Fault-Zone Properties and Earthquake
Rupture Dynamics ............................................. 1
Eiichi Fukuyama
2. Geometry and Slip Distribution of Coseismic Surface
Ruptures Produced by the 2001 Kunlun, Northern Tibet,
Earthquake .................................................. 15
Aiming Lin
1. Introduction ................................................ 16
2. Tectonic Setting ............................................ 18
3. Deformation Characteristics of the 2001 Coseismic Surface
Rupture ..................................................... 19
3.1. Geometric Distribution and Deformational Structure ..... 19
3.2. Coseismic Slip Distribution ............................ 24
3.2.1. Measurement Method of Strike-Slip Offset ........ 24
3.2.2. Field Observations .............................. 26
3.2.3. Analysis of High-Resolution Remote Sensing
Images .......................................... 28
3.2.4. Seismic Inversion Results ....................... 29
4. Discussion .................................................. 30
4.1. Relationship between the Coseismic Surface Rupture
and Preexisting Fault .................................. 30
4.2. Coseismic Strike-Slip Displacement ..................... 31
5. Conclusions ................................................. 33
3. Aseismic-Seismic Transition and Fluid Regime along
Subduction Plate Boundaries and a Fossil Example from
the Northern Apennines of Italy ............................. 37
Paola Vannucchi, Francesca Remitti, Jason Phipps-
Morgan and Giuseppe Bettelli
1. Introduction ................................................ 38
2. Deformation and Seismogenesis at Accretionary and
Erosive Subduction Margins .................................. 40
3. Seismogenic Zone: Definition ................................ 42
4. Slow Slip Events and Seismic Tremors ........................ 46
5. Seismically Produced Structures ............................. 48
6. The Up-Dip Limit of Seismogenesis in a Fossil Erosive
Subduction Channel .......................................... 52
6.1. Subduction Channel Architecture ........................ 53
6.2. Subduction Channel Internal Structure: A Low-
Friction Plate Boundary ................................ 55
7. Discussion and Comparison between Erosive and
Accretionary Seismogenic Zones .............................. 58
8. Conclusions and Future Perspective .......................... 59
4. Fault Zone Structure and Deformation Processes
along an Exhumed Low-Angle Normal Fault-Implications
for Seismic Behavior ........................................ 69
Cristiano Collettini, Robert E. Holdsworth and Steven
A.F. Smith
1. Introduction ................................................ 70
2. Regional Setting ............................................ 71
3. Fault Zone Architecture ..................................... 73
3.1. Geometry and Kinematics ................................ 73
3.2. Fault Rock Distribution and Microstructures ............ 75
4. Discussion .................................................. 78
4.1. Fault Rock Evolution ................................... 78
4.2. The Mechanical Paradox of Low-Angle Normal Faults ...... 79
4.3. A Slip Model for Low-Angle Normal Faults
(Evidences That ZF Was Active as LANF) ................. 80
5. Conclusions ................................................. 82
5. Pseudotachylytes and Earthquake Source Mechanics ............ 87
Ciulio Di Тоrо, Giorgio Pennacchioni and Stefan Nielsen
1. Introduction ................................................ 87
2. Pseudotachylytes ............................................ 89
2.1. Mesoscale Geometry of Pseudotachylyte .................. 90
2.2. Microstructures and Geochemistry in Pseudotachylytes ... 91
2.3. Temperature Estimate of Frictional Melts ............... 93
2.4. Distribution of Tectonic Pseudotachylytes .............. 94
2.5. Production of Pseudotachylytes ......................... 95
2.5.1. The Role of Water ............................... 99
3. A Natural Laboratory of an Exhumed Seismogenic Source ...... 100
4. Rupture Dynamics ........................................... 104
4.1. Transient Stress Pattern .............................. 104
4.2. Examples of Transient Stress Markers Observed ......... 105
5. Dynamic Fault Strength ..................................... 110
5.1. Field Estimates ....................................... 111
5.2. Experimental Results .................................. 113
5.3. Theoretical Estimates ................................. 116
6. Discussions and Conclusions ................................ 120
6.1. A New Approach to the Study of Exhumed
Pseudotachylyte-Bearing Faults ........................ 123
6. The Critical Slip Distance for Seismic and Aseismic
Fault Zones of Finite Width ................................ 135
Chris Marone, Massimo Cocco, Eliza Richardson and
Elisa Tinti
1. Introduction ............................................... 136
2. Friction Laws and the Transition from Static to Kinetic
Friction ................................................... 139
3. Contact Model for the Critical Slip Distance of Solid
Surfaces and Shear Zones ................................... 140
4. Model for a Shear Zone of Finite Thickness ................. 143
5. Results .................................................... 146
6. Implications for Scaling of the Dynamic Slip Weakening
Distance ................................................... 151
7. Discussion ................................................. 154
7. Scaling of Slip Weakening Distance with Final Slip
during Dynamic Earthquake Rupture .......................... 163
Massimo Cocco, Elisa Tinti, Chris Marone and Alessio
Piatanesi
1. Introduction ............................................... 164
2. Rupture History from Kinematic Source Models ............... 167
3. Inferring Traction Evolution ............................... 169
4. Measuring Dc'from Peak Slip Velocity ....................... 172
5. Measuring Dc from Inferred Traction Evolution Curves ....... 174
6. Scaling between Dc and Final Slip .......................... 179
7. Discussion and Concluding Remarks .......................... 180
8. Rupture Dynamics on Bimaterial Faults and Nonlinear
Off-Fault Damage ........................................... 187
Teruo Yamashita
1. Introduction ............................................... 187
2. Formation of Damage Zone due to Dynamic Fault Growth ....... 191
2.1. Inference about Orientation and Distribution of
Secondary Fractures ................................... 191
2.2. Modeling of Generation of Tensile Microfractures ...... 193
2.3. Modeling of Dynamic Generation of Mesoscopic
Shear Branches ........................................ 195
2.4. Effects of Damage on Earthquake Rupture in a
Poroelastic Medium .................................... 196
2.5. Rheology of Damage Zone ............................... 197
3. Fault Growth on a Bimaterial Interface ..................... 199
3.1. Field Observation of Faults ........................... 199
3.2. Quasi-Static Features of In-Plane Tensile Crack ....... 199
3.3. Theoretical and Numerical Studies of Dynamic Fault
Slip .................................................. 199
3.4. Regularization of an III-Posed Problem ................ 205
3.5. Poroelastic Bimaterial Effects on Fault Slip .......... 206
3.6. How Much Are Earthquake Ruptures Influenced by
Bimaterial Effects? ................................... 207
3.7. Macroscopic Parameter Affected by the Existence of
Fault at Bimaterial Interface ......................... 209
4. Concluding Remarks ......................................... 209
9. Boundary Integral Equation Method for Earthquake
Rupture Dynamics ........................................... 217
Taku Tada
1. Introduction ............................................... 217
2. Basic Equations ............................................ 218
2.1. General Description ................................... 218
2.2. Planar Fault of Two-Dimensional Nature ................ 221
2.3. Three- and Two-Dimensional Green's Functions .......... 223
2.4. Planar Fault of Three-Dimensional Nature .............. 225
3. Regularization ............................................. 226
3.1. Hypersingularities in the Integration Kernels ......... 226
3.2. Planar Two-Dimensional Antiplane Fault ................ 227
3.3. Planar Three-Dimensional Fault ........................ 228
3.4. Planar Two-Dimensional In-Plane Fault ................. 231
3.5. Isolating the Instantaneous Response Term ............. 232
4. Spatiotemporal Discretization .............................. 233
4.1. Boundary Elements and Time Steps ...................... 233
4.2. Discretizing the Equations ............................ 234
4.3. Implicit Time-Marching Scheme ......................... 237
4.4. Courant-Friedrichs-Lewy Condition and the Explicit
Time-Marching Scheme .................................. 237
5. Evaluating Discrete Integration Kernels .................... 239
5.1. Planar Two-Dimensional Antiplane Fault ................ 239
5.2. Planar Two-Dimensional In-Plane Fault ................. 243
5.3. Planar Three-Dimensional Fault ........................ 245
5.4. Interface with the Two-Dimensional Theory ............. 247
6. Dealing with Nonplanar Faults .............................. 248
6.1. Overview .............................................. 248
6.2. Evaluating Discrete Integration Kernels ............... 250
6.3. Inventory of Available Stress Response Functions ...... 252
6.3.1. Linear Fault Element in a Two-Dimensional
Medium ......................................... 252
6.3.2. Rectangular Fault Element in a Three-
Dimensional Medium ............................. 253
6.3.3. Triangular Fault Element in a Three-
Dimensional Medium ............................. 254
6.4. Numerical Modeling Studies in the Literature .......... 254
7. Numerical Stability ........................................ 255
8. Related Topics ............................................. 256
8.1. Fracture Criterion .................................... 256
8.2. Formulation in the Fourier and Laplace Domains ........ 257
8.3. Displacement Discontinuity BIEM ....................... 258
8.4. Fault Opening ......................................... 258
8.5. Faults in a Half-Space ................................ 260
8.6. Galerkin Method ....................................... 262
9. Conclusion ................................................. 263
10.Dynamic Rupture Propagation of the 1995 Kobe, Japan,
Earthquake ................................................. 269
Eiichi Fukuyama
1. Introduction ............................................... 269
2. Computation Method ......................................... 272
3. Fault Model ................................................ 273
4. Computation Results ........................................ 275
5. Discussion and Conclusion .................................. 277
List of Abbreviations ......................................... 285
Index ......................................................... 289
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