M5.9 - OFFSHORE NORTHERN CALIFORNIA

Tectonic Summary

The earthquake's epicenter is west of the Mendocino Triple Junction, which is formed by the intersection of the Mendocino fracture zone, the San Andreas fault and the Cascadia subduction zone.

Preliminary analysis of the earthquake indicates that it results from slip on a near vertical strike-slip fault. There are no reports of this earthquake causing a tsunami. Strike-slip earthquakes are less likely to produce large tsunamis because they cause relatively little vertical ground displacement.

This earthquake occurred 30 km southwest of the magnitude 6.5 earthquake of January 10, 2010. Other significant earthquakes in this region include the April 25, 1992 M7.2 Cape Mendocino and the June 15, 2005 M7.2 Gorda plate earthquakes.