Surface displacements in the 1906 San Francisco and 1989 Loma Prieta earthquakes

Paul Segall; Michael Lisowski

doi:10.1126/science.250.4985.1241

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Surface displacements in the 1906 San Francisco and 1989 Loma Prieta earthquakes

Paul Segall·Michael Lisowski

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Abstract

The horizontal displacements accompanying the 1906 San Francisco earthquake and the 1989 Loma Prieta earthquake are computed from geodetic survey measurements. The 1906 earthquake displacement field is entirely consistent with right-lateral strike slip on the San Andreas fault. In contrast, the 1989 Loma Prieta earthquake exhibited subequal components of strike slip and reverse faulting. This result, together with other seismic and geologic data, may indicate that the two earthquakes occurred on two different fault planes.

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Source-reported bounding extent: 34.0632673476597° to 38.82174328366341° latitude; -123.27020842664194° to -118.99544692365996° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Paul Segall, Michael Lisowski. 1990. Surface displacements in the 1906 San Francisco and 1989 Loma Prieta earthquakes. https://doi.org/10.1126/science.250.4985.1241

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