A magnitude 8.0 earthquake struck off Santa Cruz Island, part of the Solomon Islands, in the southwest Pacific Ocean February 6 at 12:12 p.m. local time. The quake triggered a tsunami and numerous aftershocks, including at least three with magnitudes greater than 6.0.
The tsunami killed at least five people and damaged homes in several villages, according to a Reuters news story.
The quake hit 81 kilometers west of the town of Lata on Santa Cruz Island, at a depth of 28.7 kilometers beneath the seafloor, according to the U.S. Geological Survey. The temblor occurred either on or near the boundary between two plates of Earthââ¬â¢s crust, where the northeast-moving Australian plate dives beneath the Pacific plate. Large earthquakes are common where such plate collisions occur.
The earthquake happened on a thrust fault, which means that one side of the fault pushes up during a quake. This upward movement of the seafloor displaced a huge volume of water, unleashing a tsunami that reached several islands in the region. At the Lata Wharf, the wave measured 91 centimeters above normal sea level, the Pacific Tsunami Warning Center reported.
Given the quakeââ¬â¢s size and depth, geophysicist Jessica Turner of the USGS Earthquake Information Center in Golden, Colo., was not surprised that a tsunami formed. ââ¬ÅWe usually see tsunamis beginning around magnitude 7 and with a shallow depth ââ¬â anything under 50 kilometers,ââ¬Â she says.
Residents of the Solomon Islands are no strangers to large earthquakes. In April 2007, a magnitude 8.1 quake rocked the country, striking about 700 kilometers northwest of the February 6 temblor. A magnitude 7.1 event struck in January 2010. And in the month leading up to todayââ¬â¢s earthquake, seismometers recorded dozens of quakes in the region, seven with a magnitude of 6.0 or higher.
