An earthquake measuring 5.7 on the Richter scale jolted 102 km northwest of Kokoda, Papua New Guinea at 13:40:59 GMT on Monday (21:40:59 Beijing Time), the U.S. Geological Survey said. The epicenter, with a depth of 10.0 km, was initially determined to be at 8.3179 degrees south latitude and 146.998 degrees east longtitude.