Near-field investigations of the Landers earthquake sequence, April to July 1992

K. Sieh; L. Jones; E. Hauksson; K. Hudnut; D. Eberhart-Phillips; T. Heaton; S. Hough; K. Hutton; H. Kanamori; A. Lilje; Scott Lindvall; S.F. McGill; J. Mori; C. Rubin; J.A. Spotila; J. Stock; H.K. Thio; J. Treiman; B. Wernicke; J. Zachariasen

doi:10.1126/science.260.5105.171

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Near-field investigations of the Landers earthquake sequence, April to July 1992

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Abstract

The Landers earthquake, which had a moment magnitude ( M w ) of 7.3, was the largest earthquake to strike the contiguous United States in 40 years. This earthquake resulted from the rupture of five major and many minor right-lateral faults near the southern end of the eastern California shear zone, just north of the San Andreas fault. Its M w 6.1 preshock and M w 6.2 aftershock had their own aftershocks and foreshocks. Surficial geological observations are consistent with local and far-field seismologic observations of the earthquake. Large surficial offsets (as great as 6 meters) and a relatively short rupture length (85 kilometers) are consistent with seismological calculations of a high stress drop (200 bars), which is in turn consistent with an apparently long recurrence interval for these faults.

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Source-reported bounding extent: 33° to 36° latitude; -119° to -115° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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K. Sieh, L. Jones, E. Hauksson, K. Hudnut, D. Eberhart-Phillips, T. Heaton, S. Hough, K. Hutton, H. Kanamori, A. Lilje, Scott Lindvall, S.F. McGill, J. Mori, C. Rubin, J.A. Spotila, J. Stock, H.K. Thio, J. Treiman, B. Wernicke, J. Zachariasen. 1993. Near-field investigations of the Landers earthquake sequence, April to July 1992. https://doi.org/10.1126/science.260.5105.171

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