The Elsinore Fault Zone is a large geological fault structure in Southern California.
It runs from the mountainous region between El Centro and San Diego, northwest to Chino Hills. On the southern end of the fault zone is the southeastern extension of the Elsinore fault zone, the Laguna Salada Fault. At its northern end, the Elsinore fault zone splits into two segments, the Chino Fault and the Whittier Fault.
The Elsinore fault zone, not including Whittier, Chino, and Laguna Salada faults, is 180 kilometers (111 miles) long. Its slip rate is 4.0 millimeters/year (0.15 in/yr). It is estimated that this zone is capable of producing a quake of 6.5 – 7.5 MW. The projected interval between major rupture events is 250 years.
The main fault zone is one of the quietest in California, producing only one earthquake above magnitude 5.2 in known history, an estimated magnitude 6 event in 1910, however this quake did little damage and produced no surface rupture.
