Seismic Amplitude Measurements Suggest Foreshocks Have Different Focal Mechanisms than Aftershocks
- 7 July 1978
- journal article
- other
- Published by American Association for the Advancement of Science (AAAS) in Science
- Vol. 201 (4350) , 56-59
- https://doi.org/10.1126/science.201.4350.56
Abstract
The ratio of the amplitudes of P and S waves from the foreshocks and aftershocks to three recent California earthquakes show a characteristic change at the time of the main events. As this ratio is extremely sensitive to small changes in the orientation of the fault plane, a small systematic change in stress or fault configuration in the source region may be inferred. These results suggest an approach to the recognition of foreshocks based on simple measurements of the amplitudes of seismic waves.Keywords
This publication has 15 references indexed in Scilit:
- Prediction of the Haicheng earthquakeEos, 1977
- Long- and short-term earthquake prediction in KamchatkaTectonophysics, 1977
- SEISMOLOGICAL PRECURSORS TO A MAGNITUDE 5 EARTHQUAKE IN THE CENTRAL ALEUTIAN ISLANDSJournal of Physics of the Earth, 1977
- Frequency of foreshocksNature, 1976
- Anomalous tilt preceding the Hollister earthquake of November 28, 1974Journal of Geophysical Research, 1976
- A tectonomagnetic effect observed before a magnitude 5.2 earthquake near Hollister, CaliforniaJournal of Geophysical Research, 1976
- Oroville Earthquakes: Normal Faulting in the Sierra Nevada FoothillsScience, 1976
- Possible criteria for predicting earthquake locations and their application to major plate boundaries of the Pacific and the CaribbeanJournal of Geophysical Research, 1973
- The processes preceding strong earthquakes in some regions of middle AsiaTectonophysics, 1972
- Progress of earthquake prediction in KamchatkaTectonophysics, 1972