Geomorphic features and recent crustal movement in Solomon Islands: its neotectonic implication

The Solomon Islands are situated as a section of the Pacific fire-ring, seismically and volcanically active. Tectonically it has been defined as a convergent plate boundary, where the inter-plate action is the subduction along two connected trenches: San Cristobal and New Britain. Currently the subduction interface is dipping to the northeast, driving the Australian Plate and two incremental microplates (i.e. Woodlark Plate and Solomon Sea Plate) to underthrust beneath the Solomon Islands. Three large earthquakes of M8.1, 7.1, and 8.0 struck this area in 2007, 2010, and 2013 respectively. As well, a number of historical volcanic eruptions have been recorded including the most recent one at Tinakula Volcano. For the purpose of hazard mitigation and prevention in this region, to realize the neotectonic framework of Solomon Islands is a fundamental work and urgently needed. Combined with our previous c-GPS monitoring in the western province, a synthesized project is launched to identify the geomorphic features related to crustal uplift and subsidence all around islands. The results present a general pattern for the crustal deformation of Solomon Islands, which may reflect the dimension of the mechanical controls along the subduction interface.