An earthquake measuring 6.1 degrees on the Richter scale jolted off Vanuatu islands on Thursday, the U.S. Geological Survey said. The epicenter, with a depth of 15.10 km, was initially determined to be at 17.7706 degrees south latitude and 167.3409 degrees east longitude. The quake happened at 2:09:44 p.m. local time with epicenter locating 102 km west from Port Vila, the capital of the South Pacific islands country.