490 Index
Central Indian Ocean ridge, 295, 329
central limit theorem, 392
centroid moment tensor project (CMT) see
Harvard centroid moment tensor project
Chagos–Laccadive ridge, 329n4
Chang Heng, 400–1
chaos theory, 24n11
characteristic polynomial, 457
Chile earthquake (1960), 11, 110, 265, 266, 321,
323
Chilean subduction zone, 323
China, earthquake prediction, 25–6
circular fault, 269
Clapeyron slope, 315–16
CLVD see compensated linear vector dipole
CMB see core–mantle boundary
CMP see common midpoint
CMT see Harvard centroid moment tensor project
Cocos plate, 294–5
coda, 189
coefficient of internal friction, 351
coefficient of sliding friction, 352
coefficient of thermal expansion, 201
cohesive strength, 351
collision, between plates, 336–9
common depth point (CDP) stack, 144
common midpoint (CMP) stacking, 141–4,
395–7
common source point (CSP), seismograms, 141
compensated linear vector dipole (CLVD), 245–6,
250
complex Fourier series, 371–2
complex numbers, properties, 443–4
composite structures, anisotropy, 180
Comprehensive Test Ban Treaty (CTBT), 27
compression, 40
compressional (P) axis, 221, 226–7, 243–4
compressional quadrant, 5, 219
compressional waves see P waves
compressive stress, 40, 351
computers
scientific programming, 466–74
solving linear equations, 453–4
Conrad discontinuity, 130
constitutive equations, 38, 48–51
continental drift, 9, 286, 295–6
continental earthquakes, 333–48
continental lithosphere, 287
continental plates
deformation, 339–43
plate boundary zones, 334–9
rifting, 333–4, 343, 345
continuum mechanics, 38
convolution
digital, 390–1
in earthquake modeling, 229–34
linear systems, 378, 379–80
in reflection seismology, 150–1
coordinate transformations, vectors, 455–6
coordinates
Cartesian coordinate system, 445, 455
polar, 443
spherical, 462–6
core of earth
anelasticity, 198
anisotropy, 182–5
body wave phases, 166–9
chemical composition of, 205, 208–10
inner core boundary (ICB), 162, 209–10
regions of, 162
core–mantle boundary (CMB), 105n4, 162,
174
density changes, 202
temperature, 204, 209
Coriolis force, 114
corner frequencies, 267, 270
coseismic displacement, 217, 254–6
Coulomb–Mohr failure criterion, 351, 362–3
coupling
of earth’s modes, 114–15
of P–SV waves, 64
see also seismic coupling
covariance, 394, 421
cracks, fluid-filled, 181
critical angle, waves at interface, 67–8, 78,
121
critical distance, refracted waves, 121
creep, 262
cross product, 447–8
cross-correlation, seismograms, 151, 383–5
crossover distance, refraction seismology, 121
crust
anisotropy, 180–2
attenuation, 197–8
boundary with mantle (Moho), 122, 130
geological composition, 130–4
refraction studies, 128–31
CSP see common source point
curl, vector fields, 460–1
D′′ region
composition of, 207–8
structure of, 171–4
temperature, 204
damped harmonic oscillator
model for anelasticity, 190–4
model for seismometer, 398–9
damped least squares solution, 430
damping factor, 190, 398
dams, earthquake damage, 18
data see seismic data
data space inversion, 436–7, 439
decomposition
matrix (Lanczos), 427, 429
moment tensor, 246, 250–1
vector field (Helmholtz), 54n3
deconvolution
earthquake source, 235, 380
linear systems, 80
in reflection seismology, 148–51
deformation
coseismic, 254–9
interseismic, 259–63
measuring, 251–4
permanent or transient, 342–3
postseismic, 365
regional, 364–5
rheology, 349–50
seismic or aseismic, 339–42
theoretical models, 349–66
degeneracy of normal modes, 104
delay time, 181, 232
delta functions
application to deconvolution, 150–1, 380
Dirac, 375–7
Kronecker, 449
density, within the earth, 199–202
deep earthquakes
definition, 308
relation to subduction, 310–21
depth of earthquakes
classification, 308
determining, 6–7, 232–4, 238
and lithospheric properties, 303, 357–62
at ridges, 305
at continental rifts, 334
at subduction zones, 310, 312, 318
depth of ocean, 301–3
deviatoric stresses, 45–6
DFT see Discrete Fourier Transform
diagonalized stress tensor, 43
differential interferogram, 253
diffraction, 2, 72–5, 153
and core phases, 167–8
diffraction hyperbola, 153
diffraction sum migration, 153
digital convolution, 390–1
digital seismographs, 251, 404
dilatation
volume change, 48
seismic first motion, 219
dilatational quadrant, 5, 219
dip angle, 218
dip filters, 147
dip-slip faulting, 218, 225–6, 236, 244, 256,
269–70
Dirac comb, 385–6
Dirac, Paul, 443n1
Dirac delta function, 375–7
direct wave, refraction seismology, 120
direction cosines, 455
directivity, 231
Discrete Fourier Transform (DFT), 387–91
dislocation, 265–6
dispersion
dispersive signals, 94–6
geometrical, 96–9
normal mode, 107–10
physical, 96, 194–6
surface waves, 87, 96–100, 433
tsunamis, 99–101
dispersion relations, 90, 107
displacement
potentials for, 54, 63
string wave, 30
seismic wave, 53–7, 63–5
static (coseismic), 254–6
distance, spherical coordinates, 464
divergence, vector field, 459–60
divergence theorem, 460
Dix equation, 136
Doppler effect, 231
dot product, 446–7
double-couple source, 220, 240, 242
downward continuation, 155
ductile flow, 355–7
ductile materials, 349
dunite, in mantle, 205
dynamic friction, 359
dynamic range of seismometers, 400
earth
anelastic structure, 197–8, 437
anisotropic structure, 177–85
density, 199–202
interfaces within, 75
models, 62–3, 119, 162, 202–3, 434–9
normal modes, 101–15
pressure in, 202
surface boundary conditions, 51–2
Central Indian Ocean ridge, 295, 329
central limit theorem, 392
centroid moment tensor project (CMT) see
Harvard centroid moment tensor project
Chagos–Laccadive ridge, 329n4
Chang Heng, 400–1
chaos theory, 24n11
characteristic polynomial, 457
Chile earthquake (1960), 11, 110, 265, 266, 321,
323
Chilean subduction zone, 323
China, earthquake prediction, 25–6
circular fault, 269
Clapeyron slope, 315–16
CLVD see compensated linear vector dipole
CMB see core–mantle boundary
CMP see common midpoint
CMT see Harvard centroid moment tensor project
Cocos plate, 294–5
coda, 189
coefficient of internal friction, 351
coefficient of sliding friction, 352
coefficient of thermal expansion, 201
cohesive strength, 351
collision, between plates, 336–9
common depth point (CDP) stack, 144
common midpoint (CMP) stacking, 141–4,
395–7
common source point (CSP), seismograms, 141
compensated linear vector dipole (CLVD), 245–6,
250
complex Fourier series, 371–2
complex numbers, properties, 443–4
composite structures, anisotropy, 180
Comprehensive Test Ban Treaty (CTBT), 27
compression, 40
compressional (P) axis, 221, 226–7, 243–4
compressional quadrant, 5, 219
compressional waves see P waves
compressive stress, 40, 351
computers
scientific programming, 466–74
solving linear equations, 453–4
Conrad discontinuity, 130
constitutive equations, 38, 48–51
continental drift, 9, 286, 295–6
continental earthquakes, 333–48
continental lithosphere, 287
continental plates
deformation, 339–43
plate boundary zones, 334–9
rifting, 333–4, 343, 345
continuum mechanics, 38
convolution
digital, 390–1
in earthquake modeling, 229–34
linear systems, 378, 379–80
in reflection seismology, 150–1
coordinate transformations, vectors, 455–6
coordinates
Cartesian coordinate system, 445, 455
polar, 443
spherical, 462–6
core of earth
anelasticity, 198
anisotropy, 182–5
body wave phases, 166–9
chemical composition of, 205, 208–10
inner core boundary (ICB), 162, 209–10
regions of, 162
core–mantle boundary (CMB), 105n4, 162,
174
density changes, 202
temperature, 204, 209
Coriolis force, 114
corner frequencies, 267, 270
coseismic displacement, 217, 254–6
Coulomb–Mohr failure criterion, 351, 362–3
coupling
of earth’s modes, 114–15
of P–SV waves, 64
see also seismic coupling
covariance, 394, 421
cracks, fluid-filled, 181
critical angle, waves at interface, 67–8, 78,
121
critical distance, refracted waves, 121
creep, 262
cross product, 447–8
cross-correlation, seismograms, 151, 383–5
crossover distance, refraction seismology, 121
crust
anisotropy, 180–2
attenuation, 197–8
boundary with mantle (Moho), 122, 130
geological composition, 130–4
refraction studies, 128–31
CSP see common source point
curl, vector fields, 460–1
D′′ region
composition of, 207–8
structure of, 171–4
temperature, 204
damped harmonic oscillator
model for anelasticity, 190–4
model for seismometer, 398–9
damped least squares solution, 430
damping factor, 190, 398
dams, earthquake damage, 18
data see seismic data
data space inversion, 436–7, 439
decomposition
matrix (Lanczos), 427, 429
moment tensor, 246, 250–1
vector field (Helmholtz), 54n3
deconvolution
earthquake source, 235, 380
linear systems, 80
in reflection seismology, 148–51
deformation
coseismic, 254–9
interseismic, 259–63
measuring, 251–4
permanent or transient, 342–3
postseismic, 365
regional, 364–5
rheology, 349–50
seismic or aseismic, 339–42
theoretical models, 349–66
degeneracy of normal modes, 104
delay time, 181, 232
delta functions
application to deconvolution, 150–1, 380
Dirac, 375–7
Kronecker, 449
density, within the earth, 199–202
deep earthquakes
definition, 308
relation to subduction, 310–21
depth of earthquakes
classification, 308
determining, 6–7, 232–4, 238
and lithospheric properties, 303, 357–62
at ridges, 305
at continental rifts, 334
at subduction zones, 310, 312, 318
depth of ocean, 301–3
deviatoric stresses, 45–6
DFT see Discrete Fourier Transform
diagonalized stress tensor, 43
differential interferogram, 253
diffraction, 2, 72–5, 153
and core phases, 167–8
diffraction hyperbola, 153
diffraction sum migration, 153
digital convolution, 390–1
digital seismographs, 251, 404
dilatation
volume change, 48
seismic first motion, 219
dilatational quadrant, 5, 219
dip angle, 218
dip filters, 147
dip-slip faulting, 218, 225–6, 236, 244, 256,
269–70
Dirac comb, 385–6
Dirac, Paul, 443n1
Dirac delta function, 375–7
direct wave, refraction seismology, 120
direction cosines, 455
directivity, 231
Discrete Fourier Transform (DFT), 387–91
dislocation, 265–6
dispersion
dispersive signals, 94–6
geometrical, 96–9
normal mode, 107–10
physical, 96, 194–6
surface waves, 87, 96–100, 433
tsunamis, 99–101
dispersion relations, 90, 107
displacement
potentials for, 54, 63
string wave, 30
seismic wave, 53–7, 63–5
static (coseismic), 254–6
distance, spherical coordinates, 464
divergence, vector field, 459–60
divergence theorem, 460
Dix equation, 136
Doppler effect, 231
dot product, 446–7
double-couple source, 220, 240, 242
downward continuation, 155
ductile flow, 355–7
ductile materials, 349
dunite, in mantle, 205
dynamic friction, 359
dynamic range of seismometers, 400
earth
anelastic structure, 197–8, 437
anisotropic structure, 177–85
density, 199–202
interfaces within, 75
models, 62–3, 119, 162, 202–3, 434–9
normal modes, 101–15
pressure in, 202
surface boundary conditions, 51–2