Anisotropy and crustal structure of the Cocos plate

Abstract

Seismic studies in two locations on the Cocos Plate, southeast and northwest of the Tehuantepec Ridge, have shown that there is significant anisotropy with the high-velocity direction northeast-southwest and that there is a generally shallow mantle in this area of relatively shallow water and low heat flow. The mantle depth is uniformly about 8 to 8-1/2 km deep between the Clipperton fracture zone and the Guerrero fracture Zone at 13.5°N. At this point it drops to about 9-1/2 km depth.