The course will focus on ground motion that is recorded near the earthquake source. How are the ground motions related to the dynamics of faulting? The course will start with a description of ground motion from a point source and move on to ground motion from a finite fault. Topics that will be covered are the parameters of a spectral model of an earthquake such as stress drop, seismic moment and corner frequency (Aki, 1967, JGR and Brune 1970, JGR), directivity effects due to rupture velocity, polarization of ground motion, spatial variation from radiation pattern effects, isochrones, attenuation and site amplification due to local structure.
* Course available depending on the number of interested students.
Chapters 3, 4, 10 and 11 of Aki and Richards, Quantitative Seismology, 2nd Edition. (or Chapters 3, 4, 14 and 15 of Aki and Richards, Quantitative Seismology 1st Edition.)
Chapters 2 and 3 of Steven Kramer, Geotechnical Earthquake Engineering.
Aki, K., 1967. Scaling law of seismic spectrum, J. Geophys. Res., 72, 1217‐1231.
Archuleta, R. J., 1984. A faulting model for the 1979 Imperial Valley, earthquake, J. Geophys. Res., 89, 4559‐4585.
Brune, J. N., 1972. Tectonic stress and the spectra of seismic shear waves from earthquakes, J. Geophys. Res., 75, 4997‐5009. Correction (ibid.) 76, 5002.
Madariaga, R., 1976. Dynamics of an expanding circular fault, Bull. Seism. Soc. Am., 66, 639‐666.
Spudich, P. & Frazer, L.N., 1984. Use of ray theory to calculate high frequency radiation from earthquake sources having spatially variable rupture velocity and stress drop, Bull. Seism. Soc. Am., 74, 2061–2082.