Normal faulting and viscous buckling in the Tibetan Plateau induced by a weak lower crust

Abstract

Weak lower crustal flow in Tibet has been invoked to reconcile geophysical observations, yet viscosity estimates vary from 1016 to 1021 Pa·s. Here the authors show that viscous buckling of the upper crust in response to lower crust flow (viscosity ~1020 Pa·s) is responsible for the observed extension in Tibet.