Seismic velocity structure beneath the Western Solomon Islands from the joint inversion of receiver functions and surface-wave dispersion curves

Abstract

An MW 8.1 earthquake occurred in 2007 and induced a tsunami that hit the Western Solomon Islands and caused casualties. This motivated us to deploy a seismic network around the rupture zone of the 2007 event. To investigate the seismic velocity structure of the Western Solomon Islands, we select seismograms of teleseismic events recorded by our seismic network. Joint inversion of P-wave receiver functions and surface-wave group velocity dispersion curves is used to estimate station-based 1-D velocity models. The resulting velocity models show a highly variable crustal structure across the region. The Moho depths beneath the stations range from 25 to 40 km. A low-velocity zone (LVZ) is observed at most seismic stations in this work. Our study provides preliminary station-based seismic velocity models for the study region, and more stations will be deployed in the continuing project. An integrated 3-D velocity model will be determined in the future.