Japan quake caused by 20-meter slip in fault line

Sat, 12 Mar 2011

Tokyo - A displacement as large as 20 meters in a fault line around 500 kilometers long probably caused the deadly earthquake which rocked north-east Japan, an expert said Saturday.

The boundary between tectonic plates several hundred kilometers off Japan went through a significant realignment in Friday's 8.9-magnitude quake, Yuji Yagi, an associate professor of seismology at the University of Tsukuba, was quoted by Kyodo News agency as saying.

"Many earthquake researchers did not expect such a quake to happen," Yagi said.

The professor also said that he had estimated its magnitude to have reached 9.0 magnitude. The Japanese Meteorological Agency put the quake at 8.8 on the Richter scale, and the US Geological Survey has said it reached a magnitude of 8.9.

Yagi told Kyodo that the northern part of the fault shifted first, and the southern part started moving 70 seconds later. The cracking in the fault continued for some 150 seconds.

The death toll from the devastating quake, the nation's biggest on record, would be well over 1,000, the government said.

Source: Earth Times.
Link: http://www.earthtimes.org/articles/news/371361,20-metre-slip-fault-line.html.