Crustal Deformation Propagation
ALASKA UNIV FAIRBANKS GEOPHYSICAL INST
Pagination or Media Count:
Tilt steps similar to strain steps have been observed for earthquakes with magnitudes ranging from 2 to 8 and distances ranging anywhere from 10 km to 12,600 kilometers. Tilt-step propagation velocities from the hypocenter to the station have been observed from 1.2 to 3.8 kmsec, and those corresponding to the arrival time of teleseismic S waves. Tilt directions, amplitudes and velocities observed at several stations simultaneously for the same earthquake are internally consistent and are likely to depend on the tectonic environment of the station in addition to the focal mechanism. The low velocity of 1.2 km sec is consistent with a plastic wave propagation. Other velocities are close to the Rayleigh wave short-period group velocity over continental paths.
- Geology, Geochemistry and Mineralogy