TheGorda plate, located beneath thePacific Ocean off the coast of northernCalifornia, is one of the northern remnants of theFarallon plate. It is sometimes referred to (by, for example, publications from theUSGSEarthquake Hazards Program)[1] as simply the southernmost portion of the neighboringJuan de Fuca plate, another Farallon remnant.
Unlike mosttectonic plates, the Gorda plate experiences significantintraplate deformation inside its boundaries. Numerous faults have been mapped in both the sediments and basement of the Gorda Basin, which is in the interior of the plate south of 41.6°N.[2] Stresses from the neighboringNorth American plate andPacific plate cause frequent earthquakes in the interior of the plate, including the1980 Eureka earthquake (also known as the Gorda Basin event).[3]
The easterly side is theCascadia subduction zone where the plate subducts under theNorth American plate in northern California. The southerly side is atransform boundary with thePacific plate along theMendocino Fault. The westerly side is adivergent boundary with the Pacific plate forming theGorda Ridge. This ridge provides morphological evidence of differing spreading rates, with the northern portion of the ridge being narrow, and the southern portion being wide.[4] The northerly side is atransform boundary with theJuan de Fuca plate, theBlanco fracture zone.
The subducting Gorda plate is connected with thevolcanoes in northern California, namely,Mount Shasta andLassen Peak. Lassen Peak last erupted in 1914–1917.[5]
41°12′N126°24′W / 41.2°N 126.4°W /41.2; -126.4
