Magnitude 7.1 quake off Sandwich Islands-USGS

WASHINGTON, Aug 20 (Reuters) A major magnitude-7.1 earthquake struck early today in the Atlantic Ocean off South America, but there was no danger of a tsunami in the region, the US Geological Survey said.

The 1:41 am quake in the Scotia Sea was 495 km from the nearest island, Bristol Island, South Sandwich Islands, the USGS said.

No tsunami alert was issued. The earthquake was caused by two plates moving horizontally, said Dale Grant, geophysicist for the National Earthquake Information Center in Golden, Colorado.

''What causes a tsunami is when plates move vertically. This was not the situation,'' he said by telephone.

He said the quake's remote location ensured there would be no damages or loss of life.

''It's just out in the middle of nowhere, it's not near anything.

A few fish might have gotten woken up but there will be no damage.

We are very lucky,'' he said.

REUTERS LL RN1147