Quote:Weird Earth Movement After Japan Earthquake Finally Explained

During the Tohoku earthquake, northeast Japan jumped 16 feet (5 meters) eastward — a permanent shift — and the seafloor closer to the fault skipped 101 feet (31 m) to the east, according to GPS data. But immediately afterward, offshore GPS receivers in the extreme damage zone were traveling westward again, a puzzling sight.

A new study explains why: Geologists were watching the Earth ooze like warm putty after a giant earthquake. The unusual westward movements provide a new picture of how the Earth adjusts after giant earthquakes, said study co-author Kelin Wang, a seismologist with the Geological Survey of Canada, part of Natural Resources Canada.