Wallace Creek, Carrizo Plain
June 27, 2003
Wallace Creek is a stream that crosses the San Andreas Fault north of Los Angeles, California on the Carrizo Plain. Like many other streams that cross the fault here, the slow but "steady" movement of the fault is pushing the lower portion of the stream (Pacific Plate, in the distance) to the right (northwest) at an average rate of several centimeters per year. This offset represents about 30,000 years of fault motion. The North American plate is in the foreground. The location is accessible by a dirt road from CA 58 leading to an interpretive trail along a particularly spectacular and accessible 2 km long stretch of the San Andreas Fault at Wallace Creek.