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Strain accumulation across the Eastern California Shear Zone at latitude 36°30'N

Weijun Gan·Jerry L. Svarc·J.C. Savage·W.H. Prescott
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Abstract

The motion of a linear array of monuments extending across the Eastern California Shear Zone (ECSZ) has been measured from 1994 to 1999 with the Global Positioning System. The linear array is oriented N54°E, perpendicular to the tangent to the local small circle drawn about the Pacific-North America pole of rotation, and the observed motion across the ECSZ is approximated by differential rotation about that pole. The observations suggest uniform deformation within the ECSZ (strike N23°W) (26 nstrain yr −1 extension normal to the zone and 39 nstrain yr −1 simple right-lateral shear across it) with no significant deformation in the two blocks (the Sierra Nevada mountains and southern Nevada) on either side. The deformation may be imposed by right-lateral slip at depth on the individual major fault systems within the zone if the slip rates are: Death Valley-Furnace Creek fault 3.2±0.9 mm yr −1 , Hunter Mountain-Panamint Valley fault 3.3±1.6 mm yr −1 , and Owens Valley fault 6.9±1.6 mm yr −1 . However, this estimate of the slip rate on the Owens Valley fault is 3 times greater than the geologic estimate.

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Journal of Geophysical Research B: Solid EarthArticle

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Weijun Gan, Jerry L. Svarc, J.C. Savage, W.H. Prescott. 2000-07-10. Strain accumulation across the Eastern California Shear Zone at latitude 36°30'N. https://doi.org/10.1029/2000jb900105

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