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Preface | |

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Acknowledgments | |

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Introduction | |

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Introduction | |

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Overview | |

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Models in seismology | |

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Seismology and society | |

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Seismic hazards and risks | |

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Engineering seismology and earthquake engineering | |

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Highways, bridges, dams, and pipelines | |

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Tsunamis, landslides, and soil liquefaction | |

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Earthquake forecasting | |

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Earthquake prediction | |

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Real-time warnings | |

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Nuclear monitoring and treaty verification | |

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Further reading | |

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Basic Seismological Theory | |

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Introduction | |

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Waves on a string | |

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Theory | |

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Harmonic wave solution | |

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Reflection and transmission | |

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Energy in a harmonic wave | |

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Normal modes of a string | |

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Stress and strain | |

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Introduction | |

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Stress | |

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Stress as a tensor | |

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Principal stresses | |

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Maximum shear stress and faulting | |

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Deviatoric stresses | |

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Equation of motion | |

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Strain | |

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Constitutive equations | |

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Boundary conditions | |

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Strain energy | |

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Seismic waves | |

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The seismic wave equation | |

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Plane waves | |

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Spherical waves | |

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P and S waves | |

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Energy in a plane wave | |

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Snell's law | |

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The layered medium approximation | |

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Plane wave potentials for a layered medium | |

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Angle of incidence and apparent velocity | |

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Snell's law | |

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Critical angle | |

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Snell's law for SH waves | |

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Ray parameter and slowness | |

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Waveguides | |

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Fermat's principle and geometric ray theory | |

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Huygens' principle and diffraction | |

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Plane wave reflection and transmission coefficients | |

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Introduction | |

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SH wave reflection and transmission coefficients | |

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Energy flux for reflected and transmitted SH waves | |

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Postcritical SH waves | |

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P-SV waves at a free surface | |

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Solid-solid and solid-liquid interfaces | |

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Examples | |

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Surface waves | |

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Introduction | |

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Rayleigh waves in a homogeneous halfspace | |

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Love waves in a layer over a halfspace | |

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Love wave dispersion | |

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Dispersion | |

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Phase and group velocity | |

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Dispersive signals | |

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Surface wave dispersion studies | |

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Tsunami dispersion | |

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Normal modes of the earth | |

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Motivation | |

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Modes of a sphere | |

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Spherical harmonics | |

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Torsional modes | |

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Spheroidal modes | |

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Modes and propagating waves | |

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Observing normal modes | |

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Normal mode synthetic seismograms | |

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Mode attenuation, splitting, and coupling | |

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Further reading | |

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Problems | |

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Seismology and Earth Structure | |

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Introduction | |

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Refraction seismology | |

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Flat layer method | |

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Dipping layer method | |

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Advanced analysis methods | |

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Crustal structure | |

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Rocks and minerals | |

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Reflection seismology | |

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Travel time curves for reflections | |

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Intercept-slowness formulation for travel times | |

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Multichannel data geometry | |

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Common midpoint stacking | |

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Signal enhancement | |

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Deconvolution | |

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Migration | |

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Data processing sequence | |

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Seismic waves in a spherical earth | |

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Ray paths and travel times | |

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Velocity distributions | |

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Travel time curve inversion | |

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Body wave travel time studies | |

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Body wave phases | |

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Core phases | |

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Upper mantle structure | |

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Lower mantle structure | |

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Visualizing body waves | |

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Anisotropic earth structure | |

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General considerations | |

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Transverse isotropy and azimuthal anisotropy | |

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Anisotropy of minerals and rocks | |

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Anisotropy of composite structures | |

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Anisotropy in the lithosphere and the asthenosphere | |

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Anisotropy in the mantle and the core | |

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Attenuation and anelasticity | |

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Wave attenuation | |

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Geometric spreading | |

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Multipathing | |

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Scattering | |

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Intrinsic attenuation | |

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Quality factor, Q | |

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Spectral resonance peaks | |

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Physical dispersion due to anelasticity | |

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Physical models for anelasticity | |

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Q from crust to inner core | |

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Composition of the mantle and the core | |

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Density within the earth | |

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Temperature in the earth | |

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Composition of the mantle | |

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Composition of D" | |

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Composition of the core | |

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Seismology and planetary evolution | |

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Further reading | |

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Problems | |

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Earthquakes | |

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Introduction | |

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Focal mechanisms | |

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Fault geometry | |

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First motions | |

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Body wave radiation patterns | |

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Stereographic fault plane representation | |

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Analytical representation of fault geometry | |

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Waveform modeling | |

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Basic model | |

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Source time function | |

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Body wave modeling | |

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Surface wave focal mechanisms | |

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Once and future earthquakes | |

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Moment tensors | |

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Equivalent forces | |

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Single forces | |

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Force couples | |

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Double couples | |

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Earthquake moment tensors | |

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Isotropic and CLVD moment tensors | |

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Moment tensor inversion | |

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Interpretation of moment tensors | |

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Earthquake geodesy | |

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Measuring ground deformation | |

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Coseismic deformation | |

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Joint geodetic and seismological earthquake studies | |

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Interseismic deformation and the seismic cycle | |

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Source parameters | |

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Magnitudes and moment | |

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Source spectra and scaling laws | |

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Stress drop and earthquake energy | |

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Earthquake statistics | |

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Frequency-magnitude relations | |

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Aftershocks | |

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Earthquake probabilities | |

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Further reading | |

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Problems | |

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Seismology and Plate Tectonics | |

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Introduction | |

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Plate kinematics | |

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Relative plate motions | |

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Global plate motions | |

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Space-based geodesy | |

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Absolute plate motions | |

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Spreading centers | |

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Geometry of ridges and transforms | |

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Evolution of the oceanic lithosphere | |

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Ridge and transform earthquakes and processes | |

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Subduction zones | |

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Thermal models of subduction | |

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Earthquakes in subducting slabs | |

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Interplate trench earthquakes | |

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Oceanic intraplate earthquakes and tectonics | |

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Locations of oceanic intraplate seismicity | |

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Forces and stresses in the oceanic lithosphere | |

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Constraints on mantle viscosity | |

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Continental earthquakes and tectonics | |

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Continental plate boundary zones | |

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Seismic, aseismic, transient, and permanent deformation | |

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Continental intraplate earthquakes | |

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Faulting and deformation in the earth | |

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Rheology | |

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Rock fracture and friction | |

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Ductile flow | |

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Strength of the lithosphere | |

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Earthquakes and rock friction | |

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Earthquakes and regional deformation | |

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Further reading | |

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Problems | |

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Seismograms as Signals | |

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Introduction | |

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Fourier analysis | |

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Fourier series | |

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Complex Fourier series | |

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Fourier transforms | |

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Properties of Fourier transforms | |

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Delta functions | |

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Linear systems | |

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Basic model | |

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Convolution and deconvolution modeling | |

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Finite length signals | |

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Correlation | |

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Discrete time series and transforms | |

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Sampling of continuous data | |

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The discrete Fourier transform | |

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Properties of DFTs | |

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The fast Fourier transform (FFT) | |

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Digital convolution | |

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Stacking | |

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Random errors | |

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Stacking examples | |

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Seismometers and seismological networks | |

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Introduction | |

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The damped harmonic oscillator | |

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Earth noise | |

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Seismometers and seismographs | |

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Digital recording | |

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Types of networks | |

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Global networks | |

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Arrays | |

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Regional networks | |

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Further reading | |

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Problems | |

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Inverse Problems | |

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Introduction | |

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Earthquake location | |

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Theory | |

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Earthquake location for a homogeneous medium | |

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Errors | |

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Earthquake location for more complex geometries | |

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Travel time tomography | |

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Theory | |

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Generalized inverse | |

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Properties of the generalized inverse solution | |

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Variants of the solution | |

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Examples | |

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Stratified earth structure | |

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Earth structure from normal modes | |

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Parameter and data space inversions | |

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Features of the solutions | |

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Inverting for plate motions | |

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Method | |

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Testing the results with x[superscript 2] and F-ratio tests | |

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Further reading | |

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Problems | |

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Mathematical and Computational Background | |

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Introduction | |

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Complex numbers | |

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Scalars and vectors | |

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Definitions | |

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Elementary vector operations | |

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Scalar products | |

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Vector products | |

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Index notation | |

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Vector spaces | |

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Matrix algebra | |

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Definitions | |

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Determinant | |

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Inverse | |

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Systems of linear equations | |

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Solving systems of equations on a computer | |

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Vector transformations | |

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Coordinate transformations | |

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Eigenvalues and eigenvectors | |

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Symmetric matrix eigenvalues, eigenvectors, diagonalization, and decomposition | |

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Vector calculus | |

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Scalar and vector fields | |

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Gradient | |

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Divergence | |

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Curl | |

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Laplacian | |

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Spherical coordinates | |

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The spherical coordinate system | |

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Distance and azimuth | |

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Choice of axes | |

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Vector operators in spherical coordinates | |

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Scientific programming | |

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Example: synthetic seismogram calculation | |

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Programming style | |

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Representation of numbers | |

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A few pitfalls | |

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Some philosophical points | |

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Further reading | |

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Problems | |

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References | |

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Solutions to selected odd-numbered problems | |

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Index | |