Uplifted ridge of granite between two strands of the
San Jacinto fault arranged in a restraining overstep. Double-headed
arrows indicate relative displacement of main blocks that bound
the shear couple that is indicated by the single-headed arrows.
Lines at each end of the block are inferred. Lines
across the block are faults, all but one of which are
normal faults arranged properly for right simple shear. The
two bounding faults each slipped about 1/2 meter right laterally
during the 1968 Borrego Mountain earthquake (M 6.8). Photographed
1986 and Copyrighted by Arthur G. Sylvester
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