VALDIVIA, CHILE, MAY 22 1960: THE LARGEST EARTHQUAKE EVER RECORDED RESULTS IN HAZARDOUS TSUNAMI & LANDSLIDES
FARRELL, Casey M., University of Wisconsin-Eau Claire Geography Major, farrelcm@uwec.edu .
The largest earthquake ever recorded happened on May 22 nd 1960 and had a magnitude of 9.5 on the Richter scale. The earthquake occurred 60 meters under the ocean’s surface at 39.5º S Lat. and 74.5º W Long. Chile is the closest country to the epicenter of the earthquake. The subduction zone off the coast of Chile is where the Nazca Plate is pulled underneath the South American Plate. The Nazca plate slid about 15 meters underneath the South American Plate sending seismic waves through the Earths surface with magnitudes that have yet to be outdone.
In this presentation the events that happened after the initial movement of the earth’s crust, are focused on in the city of Valdivia, Chile (39.8º S Lat. and 73.24º W Long.). Tectonic subsidence in this region was close to 2 meters, creating a new coastline. A series of three tsunami ranging 5-11 meters in height, destroyed the coast of Valdivia; the 10 meter run-up path dislodged structures and washed away others. Landslides damaged houses and other city structures as well as blocked rivers. The threat of a major flood and the rebuilding of the city were handled well by residents of Valdivia.