The fault is loaded by the relative motion between the Pacific and the North American plates. The model produces magnitude 6 earthquakes that repeat every 20 years on average. The model shows two earthquakes starting at different ends of the seismogenic zone, as observed at Parkfield for the 1966 and the 2004 earthquakes. The three-dimensional fault model is the California Fault Model UCERF.  Credit: Sylvain Barbot, Voice by Anthony Scott, Edited by Jennifer Pulver.