Joint imaging by teleseismic converted and multiple waves and its application in the INDEPTH‐III passive seismic array

Abstract

A joint imaging by teleseismic converted and multiple phases is put forward to image the crustal structure beneath the INDEPTH‐III passive seismic profile in the central Tibet. A depth dependent Vp/Vs ratio is adopted to map common conversion point (CCP) via a Vp/Vs scanning and stacking approach. Our new crustal image shows that the crust is divided into two sections with different Moho depth distributions and amplitudes, with the boundary nearby the Bangong‐Nujiang suture (BNS). A negative P‐to‐S amplitude band is located in the upper‐to‐middle crust, indicating a low velocity zone possibly caused by partial melting beneath the negative amplitude band. The average crustal Vp/Vs ratio estimated by our joint imaging method is higher than previous study, but is consistent with a partial melting middle‐to‐lower crust implied by many other results.