Latest Pleistocene Slip Rate of the San Bernardino Strand of the San Andreas Fault at Plunge Creek in Highland, California
Sally F. McGill, Lewis A. Owen, Ray J. Weldon, & Katherine J. KendrickPublished 2011, SCEC Contribution #1479
Radiocarbon dating of an offset channel margin of Plunge Creek of latest Pleistocene age defines the slip rate of the San Bernardino strand of the San Andreas fault to be lower than previously published estimates. The results indicate a slip rate of 12 ± 4 mm/yr since the initial incision of the terrace riser about 32 ka, and 12 ± 3 mm/yr since final modification of the riser at 10.4 ka, when the surface below the riser was abandoned. This is only half as large as the previously published slip rate for the San Andreas fault to the northwest in Cajon Pass, which has often been extrapolated southeastward along the San Bernardino section of the fault. These results suggest that about half of the 25 mm/yr rate at Cajon Pass transfers southeastward to the San Jacinto fault. However, the latest Pleistocene slip rate at Plunge Creek is twice that of rates inferred for the San Bernardino section of the San Andreas fault based on elastic block modeling of geodetic data.
Citation
McGill, S. F., Owen, L. A., Weldon, R. J., & Kendrick, K. J. (2011). Latest Pleistocene Slip Rate of the San Bernardino Strand of the San Andreas Fault at Plunge Creek in Highland, California. , : Inland Empire Chapter, Assoc. of Environ. and Eng. Geologist.
