Geologists study China earthquake

STATE COLLEGE, Pa., July 7 (UPI) -- The May 12 earthquake in China's Sichuan province, the region's first in recorded history, has U.S. geologists studying it with an eye to the future.

A team of geoscientists -- Tom Parsons of the U.S. Geological Survey, Assistant Professor Chen Ji of the University of California-Santa Barbara and Associate Professor Eric Kirby of Pennsylvania State University -- is looking at the potential for future temblors due to quake-induced changes in tectonic stress.

The researchers performed analysis of co-seismic stress transfer onto Sichuan basin faults using broad ranges because exact values for the various factors are unknown. They said such an approach enables rapid mapping of faults with a heightened likelihood of rupturing.

"We knew that the fault was there and we knew it was active," said Kirby. "I had done some previous work in the area, but I do not think anyone would have anticipated the size of this earthquake."

The May earthquake was 7.9 in magnitude and occurred at the eastern edge of the Tibetan Plateau where the Indian and Asian tectonic plates collide. Thousands of people died in the earthquake.

The scientists' detailed findings appear in the advanced online issue of the journal Nature.