Powerful 7.8-magnitude earthquake strikes off Antarctica, no tsunami

USPA News - A powerful earthquake struck near an uninhabited island off Antarctica on early Sunday morning, just a day after another strong earthquake struck the same region, seismologists said. There were no reports of damage or casualties, and no tsunami was generated.

The 7.8-magnitude earthquake at 06:04 a.m. local time (0904 GMT) was centered about 42 kilometers (26 miles) northwest of Coronation Island, an uninhabited island that is part of the South Orkney Islands in the Scotia Sea. It struck about 10 kilometers (6.2 miles) deep, making it a shallow earthquake, according to the United States Geological Survey (USGS). The Pacific Tsunami Warning Center in Hawaii initially noted a small possibility of a local or regional tsunami that could affect nearby coastlines within a few hundred kilometers, but no unusual sea level changes were recorded in the hours after the earthquake. No tsunami alerts were issued. "A destructive widespread tsunami threat does not exist based on historical earthquake and tsunami data," the center said in a bulletin. Sunday`s earthquake is the largest in a series of moderate-to-powerful earthquakes to strike the same region over the past week. The sequence began with a 6.1-magnitude earthquake on Wednesday and a 6.8-magnitude earthquake on early Saturday, followed by 10 aftershocks that ranged from 4.7 to 5.4 in magnitude later during the day. Computer models showed it was unlikely any of the tremors were felt in populated areas, and as such neither damage nor casualties were likely. However, base personnel on scientific stations in the region, which is administered under the Antarctic Treaty System, may have felt tremors from the earthquakes. "Though the region surrounding the Scotia Sea is familiar with earthquakes, the majority occur around the subduction zone adjacent to the South Sandwich Islands," the USGS said in a statement. It said only two earthquakes with a magnitude exceeding 6.0 have occurred within 250 kilometers (155 miles) of Sunday`s earthquake over the past 40 years. One was a powerful 7.6-magnitude earthquake that struck the Scotia Sea in August 2003, about 113 kilometers (70 miles) northeast of Coronation Island. That earthquake damaged instruments in the magnetic recording hut at the Argentine scientific station Orcadas Base, which is located on Laurie Island, also part of the South Orkney Islands. There were no injuries.