University of Iowa researchers are a step closer to understanding why a major fault line in the Middle East doesn’t produce the damaging earthquakes associated with other faults.
Their findings, published online in the Journal of Geophysical Research: Solid Earth, may help gauge earthquake risk in areas that lie near the fault and boost general understanding of how faults behave.
The UI team, led by Bill Barnhart, assistant professor in the Department of Earth and Environmental Sciences, used satellite images to chart changes to the earth’s surface in the region around the Chaman Fault in Pakistan and Afghanistan. They ran hundreds of computer simulations to assess what’s likely happening underground.
“The Chaman Fault forms a major plate boundary very similar to the San Andreas Fault in California, but historically has not produced large earthquakes like the San Andreas,” Barnhart says.
“We found that the fault creeps aseismically, meaning it does not lock and build the stresses needed to cause an earthquake.”
The project drew on radar images from the Envisat satellite managed by the European Space Agency. Barnhart and colleagues used the images to measure how the earth’s surface near the fault had changed over about seven years. They ran that data through a suite of analytical models to determine the sub-surface fault slip behind the changes.
The UI’s Neon high-performance computing cluster, administered by Information Technology Services, helped the team complete their models more quickly.
“A single simulation would have taken over a month to run on a desktop computer,” Barnhart says. “Using Neon, we were able to conduct hundreds of different simulations in the span of a few weeks.”
Barnhart and students also are using UI high-performance computing clusters to characterize plate tectonics and seismic hazards throughout the Middle East, generate ultra-high resolution surface maps of Southern California, and monitor increased seismic activity and earth-surface changes in Oklahoma.
“Iowa’s HPC resources have revolutionized solutions to the research problems my group addresses,” Barnhart says. “They open new opportunities in the global monitoring of earthquakes.”