The massive magnitude 8.8 earthquake that struck off the coast of Chile last month moved the entire city of Concepcion -- the closest urban area to the quake's epicenter -- at least 10 feet west, American researchers said Monday.
Chile's capital, Santiago, moved about 11 inches to the west-southwest, while Buenos Aires, all the way across the continent from the quake site, moved about an inch to the west, the researchers said. The cities of Valparaiso and Mendoza, Argentina, both northeast of Concepcion, also moved significantly.
The results were obtained from precise global positioning satellite measurements taken before and after the quake, which occurred off the Maulé coast of Chile, according to earth scientist Mike Bevis of Ohio State University. Since 1993, Bevis has headed the Central and Southern Andes GPS Project, designed to monitor crustal motion and deformation in the region.
The project has detected surface displacements as far away as the Falkland Islands and Fortaleza, Brazil. A map of the movements is available here. Bevis and others are currently in Chile to install more GPS units at sites whose previous locations are accurately known and to monitor continued movement along the fault.