The 1954 and 1980 Algerian earthquakes: Implications for the characteristic-displacement model of fault behavior

J. W. Dewey

doi:10.1785/bssa0810020446

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The 1954 and 1980 Algerian earthquakes: Implications for the characteristic-displacement model of fault behavior

J. W. Dewey

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Abstract

Joint epicenter determination of earthquakes that occurred in northern Algeria near Ech Cheliff (named Orleansville in 1954 and El Asnam in 1980) shows that the earthquake of 9 September 1954 (M=6.5) occurred at nearly the same location as the earthquake of 10 October 1980 (M=7.3). The 1954 main shock and earliest aftershocks were concentrated close to the boundaries of segment B (nomenclature of Deschamps et al., 1982; King and Yielding, 1984) of the 1980 fault system, which was to experience approximately 8 m of slip in the 1980 earthquake. Later aftershocks of the 1954 earthquake were spread over a broad area, notably in a region north of the 1980 fault system that also experienced many aftershocks to the 1980 earthquake. The closeness of the 1954 main shock and earliest aftershocks to the 1980 segment B implies that the 1954 earthquake involved either 1) rupture of segment B proper, or 2) rupture of a distinct fault in the hanging wall of footwall block of segment B.

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Bulletin of the Seismological Society of America Article

Source-reported bounding extent: 19.05736° to 37.11838° latitude; -8.6844° to 11.99951° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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J. W. Dewey. 1991. The 1954 and 1980 Algerian earthquakes: Implications for the characteristic-displacement model of fault behavior. https://doi.org/10.1785/bssa0810020446

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