Variable rates of late Quaternary strike slip on the San Jacinto fault zone, southern California.

R. V. Sharp

doi:10.1029/jb086ib03p01754

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Variable rates of late Quaternary strike slip on the San Jacinto fault zone, southern California.

R. V. Sharp

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Abstract

3 strike slip displacements of strata with known approximate ages have been measured at 2 locations on the San Jacinto fault zone. Minimum horizontal offset between 5.7 and 8.6km in no more than 0.73Myr NE of Anza indicates 8-12 mm/yr average slip rate since late Pleistocene time. Horizontal slip of 1.7m has been calculated for the youngest sediment of Lake Cahuilla since its deposition 271- 510 yr BP. The corresponding slip rate is 2.8-5.0 mm/yr. Right lateral offset of 10.9m measured on a buried stream channel older than 5060 yr BP but younger than 6820 yr BP yields average slip rates for the intermediate time periods, 400 to 6000 yr BP of 1-2 mm/yr. The rates of slip suggest a relatively quiescent period from about 4000 BC to about 1600 AD.-from Author

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R. V. Sharp. 2012-09-20. Variable rates of late Quaternary strike slip on the San Jacinto fault zone, southern California.. https://doi.org/10.1029/jb086ib03p01754

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