Strong earthquakes strike off Antarctica, no tsunami threat

[News_Editor]

Strong earthquakes strike off Antarctica, no tsunami threat

2012-01-16 09:54:37 GMT+7 (ICT)

ELEPHANT, SOUTH SHETLAND ISLANDS (BNO NEWS) -- Two strong earthquakes struck near an uninhabited island off Antarctica on late Sunday morning, seismologists said, but there were no reports of damage or casualties.

The first earthquake at 9.40 a.m. local time (1340 GMT), which had a moment magnitude of 6.6, struck about 37 kilometers (23 miles) northwest of Elephant, a mountainous island in the outer reaches of the South Shetland Islands in the Southern Ocean. It struck about 10 kilometers (6.2 miles) deep, making it a shallow earthquake, according to the United States Geological Survey (USGS).

About 40 minutes later, a 6.2-magnitude aftershock struck the same area at a depth of about 14.2 kilometers (8.8 miles), the USGS reported. Seismologists said a 5.1-magnitude aftershock followed several hours later.

With the exception of more than a dozen research stations, there are no permanent residents on the South Shetland Islands, which is administered under the Antarctic Treaty System. "There are likely to be no affected structures in this region," the USGS said.

Because earthquakes with a magnitude below 7 do normally not generate tsunamis, the Pacific Tsunami Warning Center did not issue a tsunami watch or warning. "A destructive widespread tsunami threat does not exist based on historical earthquake and tsunami data," the center said in a bulletin.

Although the earthquakes on Sunday struck along a transform fault near Elephant Island, the region does usually not experience earthquakes. The last notable earthquake in the area happened in June 2011 when a 4.9-magnitude earthquake struck northwest of Sunday's epicenter.

In September 2003, a powerful 7.6-magnitude earthquake struck the Scotia Sea, about 614 kilometers (381 miles) east of Sunday's epicenter. The earthquake in 2003 caused minor damage at Orcadas Base on Laurie Island.

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