Hearing the Japanese Earthquake (1 of 3) (VIDEO) Georgia Institute of Technology This video is under embargo. Please login to access this video. To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Caption This recording was taken about 90 miles from the Japanese earthquake's epicenter. There are two distinct sound waves. Both are caused by the mainshock. A "pop" is heard 90 seconds (in actual time) after the main event. This pop wasn't recorded at any other nearby stations, leading Georgia Tech Associate Professor Zhigang Peng to believe that either the ground shifted immediately under the measuring station, or the hill slope where the station sits in helps to amplify the shaking. It was the strongest reading he found -- a ground acceleration of nearly three g. Credit Georgia Institute of Technology Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.