Santa Cruz ): An earthquake of magnitude 6 on the Richter Scale jolted Santa Cruz, a statement by the National Center for Seismology stated on Monday. As per the NCS, the earthquake, which occurred at 23:46 IST, was shallow, with a depth of 75 kilometres. As a result, the region could be susceptible to aftershocks. In a post on X, the NCS said, "EQ of M: 6.0, On: 23/02/2025 23:46:22 IST, Lat: 11.32 S, Long: 166.17 E, Depth: 75 Km, Location: Santa Cruz Islands."
The whole of Solomon Islands, including Santa Cruz, is located on the plate boundary between the Indo-Australian plate and the Pacific plate. This highly seismic region has a "near 90° bend in the boundary..."This area experiences much plate movement as Santa Cruz Island "has upper plate strike-slip and normal faulting, plate boundary under-thrusting, outer rise extensional faulting, and intraplate faulting" and Solomon Islands is located on the subduction zone of the two boundaries. On 6 February 2013, the largest under-thrusting earthquake ever to be recorded in that area caused a tsunami, and both the earthquake and the tsunami were destructive, destroying many buildings in Temotu and damaging at least 724 homes.
The boundary between the Indo-Australian and Pacific plates has complicated faulting patterns around the arcs of Solomon Islands and Vanuatu and is used to high frequency, low to moderate intensity, seismic activity. Many of the larger events recorded have involved intraplate and interplate earthquakes with magnitudes up to about 8.0, several of which were located near the abrupt bends in the arcs.
Solomon Islands has more seismic activity than most adjacent areas, producing more earthquake "doublets" and "triplets", deviations from the normal earthquake aftershock in which a second and sometimes third earthquake can be produced from the aftershock of the first earthquake. This occurs rarely, maybe once or twice a year, making this area a unique seismic area. Local authorities have not reported significant damage or casualties from the latest quake, but aftershocks remain a possibility.