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Growth of a tectonic ridge during the Landers earthquake

R. W. Fleming·A. M. Johnson
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Abstract

The formation of tectonic ridges by localized vertical uplift along strike-slip faults has long been suspected, but the actual growth of a tectonic ridge during an earthquake has never been documented. During the 1992 Landers, California, earthquake sequence, an awl-shaped, dome-like topographic ridge along the Emerson fault zone increased its height at least 1 m concurrently with 3 m of right-lateral shift across the fault zone containing the ridge. Five deformation vectors within the ridge reveal dilatant behavior in addition to the uplift and shift on boundary faults.

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R. W. Fleming, A. M. Johnson. 1997. Growth of a tectonic ridge during the Landers earthquake. https://doi.org/10.1130/0091-7613(1997)025%3C0323%3Agoatrd%3E2.3.co%3B2

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