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

The Solomon Islands located at the southwestern Pacific Ocean, where is the complex boundary between the Pacific, Australian, and Woodlark plates. Two earthquakes occurred in 2007 and 2010 both induced tsunami to hit the Western Solomon Islands. Our group then deployed instruments around the rupture zone of the 2007 event for the seismological and geological investigations, since 2009. In this study, we select seismograms of teleseismic events recorded at our seismic network and jointly the P-wave receiver functions and surface-wave group velocity dispersion to investigate seismic velocity structure of the crust and uppermost mantle. For the Moho depth variations, our results show the shallower depth of Moho beneath stations those located near the trench, and is ranging of 20-30 km; in contrast, the stations far away from the trench have the deeper Moho depth (about 35-50 km). Even though only sparse seismic stations available in the Western Solomon Islands, we estimate the complex seismic velocity structure beneath each station. Our study provides the preliminary station-based velocity models for the region, and more stations will be added in the following project; an integrated 3-D velocity model will be available in the future.