An earthquake measuring 6.2 on the Richter scale jolted Bonin Islands in the Japan region early Tuesday, the US Geological Survey said.The temblor, which occurred at 3.55 a.m. (Beijing time) had a depth of 512.4 km. Its epicentre was initially determined to be at 28.3536 degrees north latitude and 138.864 degrees east longitude, Xinhua reported.