The earthquake struck close to the South Sandwich Islands, north of Antarctica. (Representational)

A magnitude 7.1 quake struck on Monday in the southern Pacific Ocean, close to the South Sandwich Islands north of Antarctica, the U.S. Geological Survey said.

The quake, initially reported as a magnitude 7.5, was in a remote area and fairly deep underground.

The U.S. Pacific Tsunami Warning Center said in an advisory that it did not cause a tsunami threat.