Latest Pleistocene and Holocene slip rate for the San Bernardino strand of the San Andreas fault, Plunge Creek, Southern California: Implications for strain partitioning within the southern San Andreas fault system for the last ~35 k.y.
Sally F. McGill et al., Dept. of Geological Sciences, California State University, San Bernardino, 5500 University Parkway, San Bernardino, California 92407-2397, USA. Posted online 2 October 2012; http://dx.doi.org/10.1130/B30647.1.
This study by Sandy McGill and colleagues presents a new slip-rate measurement for the San Andreas fault in the San Bernardino Valley of southern California. Two different geologic features, a ~35,000-year-old channel wall and a 10,500-year-old alluvial fan, are each offset by the fault by amounts that indicate a long-term average slip rate of 7-16 mm per year for the San Bernardino strand of the San Andreas fault. This is significantly slower than previously inferred for this section of the San Andreas fault. These results suggest that the amount of slip transferred from the Mojave section of the San Andreas fault to the San Jacinto fault may be greater than previously inferred. The new, lower, long-term slip-rate estimate is close to but somewhat faster than geodetic estimates of the rate at which tectonic plates are currently bending across the San Andreas fault.
Gobi-Tianshan connections: Field observations and isotopes from an early Permian arc complex in southern Mongolia
R.C. Economos et al., University of Southern California, Los Angeles, CA 90089, USA. Posted online 2 October 2
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