Geodetic constraint on the motion of a slab window: Implication for the Mendocino Crustal Conveyor model

Abstract

AbstractThe migration of the slab window in the Northern California Coast Ranges provides a unique setting to study the viscous coupling between crust and asthenosphere flow. The mechanisms of these dynamic processes are explained by the Mendocino Crustal Conveyor model, which predicts a 2‐D “double‐humped” surface uplift rate pattern on a 400 km long profile. To evaluate the Mendocino Crustal Conveyor (MCC) model using accurate geodetic measurements, we derive the vertical velocity field from 43 continuous GPS (CGPS) stations in the Coast Ranges region and project it onto the profile along three possible orientations of the slab window. The CGPS measured uplift rates are in good agreement with the MCC prediction, when the slab window orientation is parallel to the symmetry axis of the region of thickened crust. Thus, the CGPS solutions not only provide a complementary means to diagnose the MCC model but also provide an effective way to constrain the orientation of the slab window.