An earthquake measuring 5.5 on the Richter scale jolted 82km west-northwest of Iquique in Chile at 09:11:06 GMT on Saturday, the U.S. Geological Survey, monitored here, said. The epicenter, with a depth of 12.71 km, was initially determined to be at 20.0154 degrees south latitude and 70.9027 degrees west longitude, according to the USGS