As the Mendocino Triple Junction migrates northward along the California margin it is widely presumed to leave a "slab-free" or "asthenospheric" window in its wake. A 250-km-long south-north seismic refraction-reflection profile crossing the transition from transform to subduction regimes allows us to compare and contrast crust and upper mantle of...
The Gorda Escarpment is a north facing scarp immediately south of the Mendocino transform fault (the Gorda/Juan de Fuca-Pacific plate boundary) between 126°W and the Mendocino triple junction. It elevates the seafloor at the northern edge of the Vizcaino block, part of the Pacific plate, ~1.5 km above the seafloor...