On simultaneous tilt and creep observations on the San Andreas Fault

M.J.S. Johnston; S. McHugh; S. Burford

doi:10.1038/260691b0

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USGS · 70001094

On simultaneous tilt and creep observations on the San Andreas Fault

M.J.S. Johnston·S. McHugh·S. Burford

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Abstract

THE installation of an array of tiltmeters along the San Andreas Fault 1 has provided an excellent opportunity to study the amplitude and spatial scale of the tilt fields associated with fault creep. We report here preliminary results from, and some implications of, a search for interrelated surface tilts and creep event observations at four pairs of tiltmeters and creepmeters along an active 20-km stretch of the San Andreas Fault. We have observed clear creep-related tilts above the instrument resolution (10 −8 rad) only on a tiltmeter less than 0.5 km from the fault. The tilt events always preceded surface creep observations by 2–12 min, and were not purely transient in character.

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Source-reported bounding extent: 32.62087018318113° to 35.44277092585766° latitude; -119.091796875° to -115.42236328124999° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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M.J.S. Johnston, S. McHugh, S. Burford. 1976. On simultaneous tilt and creep observations on the San Andreas Fault. https://doi.org/10.1038/260691b0

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