An earthquake measuring 6.4 on the Richter scale jolted 18km south of Kamariotissa, Greece at 09:25:03 GMT on Saturday, the U.S. Geological Survey, monitored here, said. The epicenter, with a depth of 10.0 km, was initially determined to be at 40.3126 degrees north latitude and 25.4528 degrees east longitude, according to the USGS.