Cape Mendocino
The Mendocino Triple Junction is to the west of Cape Mendocino under the Pacific Ocean. It is a geologic triple junction where three tectonic plates come together. The San Andreas Fault, a transform boundary, runs south from the junction, separating the Pacific Plate and the North American Plate. To the north is the Cascadia subduction zone, where the Gorda Plate is being subducted under the edge of the North American plate.  Running west from the triple junction is the Mendocino Fracture Zone, the transform boundary between the Gorda Plate and the Pacific Plate.