First multi‐scale, finite‐frequency tomography illuminates 3‐D anatomy of the Tibetan Plateau

Abstract

With a new multi‐scale parameterization, 3‐D images from finite‐frequency seismic tomography, including the very first images beneath central Tibet from S ‐waves, reveal that regions of low electric resistivity in the crust, previously observed along active rifts in southern Tibet, correlate well with regions of low P ‐ and S ‐wave speeds ( V ). However, such regions are not interconnected, indicating that a prevailing south‐directed, channel‐like crustal flow seems inactive or this popular geodynamic model needs modification. In the upper mantle, there is no clear indication of regional down‐welling between depths of 100 to 400 km. Instead, a strong, lateral boundary between high and low V extends up to 33°N, marking the northern limit of sub‐horizontally advancing Indian lithospheric mantle.