Preface ...................................................... viii
1 Introduction ............................................... 1
2 Fundamentals of rock failure physics ....................... 6
2.1 Mechanical properties and constitutive relations ........... 6
2.1.1 Elastic deformation ................................. 6
2.1.2 Ductile deformation ................................. 7
2.1.3 Fracture ............................................ 9
2.1.4 Friction ........................................... 11
2.2 Basics of rock fracture mechanics ......................... 15
2.2.1 Energy release rate and resistance to rupture
growth ............................................. 15
2.2.2 Stress concentration and cohesive zone model ....... 17
2.2.3 Breakdown zone model for shear failure ............. 20
2.2.4 J-integral and energy criterion for shear
failure ............................................ 22
2.2.5 Relation between resistance to rapture growth and
constitutive relation parameters ................... 26
3 Laboratory-derived constitutive relations for shear
failure ................................................... 28
3.1 Shear failure of intact rock .............................. 28
3.1.1 Method and apparatus used .......................... 28
3.1.2 Constitutive relations derived from data on the
shear failure of intact rock ....................... 32
3.1.3 Geometric irregularity of shear-fractured
surfaces and characteristic length ................. 36
3.2 Frictional slip failure on precut rock interface .......... 39
3.2.1 Method and apparatus used .......................... 39
3.2.2 Geometric irregularity of precut fault surfaces
and characteristic length .......................... 44
3.2.3 Constitutive relations derived from data on
frictional stick-slip failure ...................... 45
3.2.4 Laboratory-derived relationships between physical
quantities observed during dynamic slip rupture
propagation ........................................ 50
3.3 Unifying constitutive formulation and a constitutive
scaling law ............................................... 55
3.3.1 Unification of constitutive relations for shear
fracture and for frictional slip failure ............ 55
3.3.2 A constitutive scaling law ......................... 61
3.3.3 Critical energy required for shear fracture and
for frictional stick-slip failure .................. 63
3.3.4 Stability/instability of the breakdown process ..... 67
3.3.5 Breakdown zone size ................................ 69
3.4 Dependence of constitutive law parameters on
environmental factors ..................................... 70
3.4.1 Introduction ....................................... 70
3.4.2 Dependence of shear failure strength on
environmental factors .............................. 72
3.4.3 Dependence of breakdown stress drop on
environmental factors .............................. 82
3.4.4 Dependence of breakdown displacement on
environmental factors .............................. 88
4 Constitutive laws for earthquake ruptures ................. 91
4.1 Basic foundations for constitutive formulations ........... 91
4.2 Rate-dependent constitutive formulations .................. 93
4.3 Slip-dependent constitutive formulations .................. 99
4.4 Depth dependence of constitutive law parameters .......... 106
5 Earthquake generation processes .......................... 121
5.1 Shear failure nucleation processes observed in the
laboratory ............................................... 121
5.1.1 Introduction ...................................... 121
5.1.2 Experimental method ............................... 122
5.1.3 Nucleation phases observed on faults with
different surface roughnesses ..................... 124
5.1.4 Scaling of the nucleation zone size ............... 139
5.2 Earthquake rupture nucleation ............................ 143
5.2.1 Seismogenic background ............................ 143
5.2.2 Physical modeling and theoretical derivation of
the nucleation zone size .......................... 145
5.2.3 Comparison of theoretical relations with
seismological data ................................ 152
5.2.4 Foreshock activity associated with the
nucleation process ................................ 157
5.3 Dynamic propagation and generation of strong motion
seismic waves ............................................ 160
5.3.1 Slip velocity and slip acceleration in the
breakdown zone .................................... 160
5.3.2 The cutoff frequency ƒmaxS of the power spectral
density of slip acceleration at the source ........ 167
5.3.3 Environmental factors for the generation of
high-frequency strong motion at the source ........ 174
6 Physical scale-dependence ................................ 179
6.1 Introduction ............................................. 179
6.2 Scaling property incorporated into the slip-dependent
constitutive law ......................................... 180
6.3 Root cause of scale-dependence ........................... 182
6.4 Physical scaling of scale-dependent physical quantities .. 187
6.4.1 Scaling relationships between Xc and Dc, and
between Lc and Dc ................................. 187
6.4.2 Physical scaling of the duration time of shear
rapture nucleation ................................ 189
6.4.3 Scale-dependence of apparent shear rupture
energy ............................................ 195
6.5 Fault heterogeneity and the Gutenberg-Richter
frequency-magnitude relation ............................. 197
7 Large earthquake generation cycles and accompanying
seismic activity ......................................... 200
7.1 The cyclical process of typical large earthquakes on
a fault .................................................. 200
7.2 The process leading up to a large earthquake and
seismic activity ......................................... 209
7.2.1 Seismic activity at later stages of the
recurrence interval ............................... 209
7.2.2 Seismic activity immediately before a mainshock
earthquake ........................................ 223
7.3 Predictability of large earthquakes ...................... 232
7.3.1 Introduction ...................................... 232
7.3.2 Long-term forecasting ............................. 234
7.3.3 Intermediate-term forecasting ..................... 236
7.3.4 Short-term forecasting ............................ 242
List of illustration credits .................................. 248
References .................................................... 251
Index ......................................................... 267
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