Small 660-km seismic discontinuity beneath Tibet implies resting ground for detached lithosphere
Journal
Journal of Geophysical Research
Journal Volume
112
Journal Issue
5
Pages
1-15
Date Issued
2007
Author(s)
Chen Wang-Ping
Abstract
Using seismic profiles comprising of high‐resolution, triplicate waveforms across apertures of over 1,000 km, we show that because of high P wave speed ( V P ) near the bottom of the mantle transition zone, the contrast in V P across the 660‐km discontinuity beneath central Tibet is small: only about 70% of that beneath the northern Indian shield. This subhorizontal anomaly of high V P is most likely a remnant of detached mantle lithosphere that recently sank to depth, thus providing key evidence for a direct connection between continental collision near the surface and deep‐seated dynamics in the mantle.
SDGs
Type
journal article