NanoScienceWorks

U. Penn, Brown Univ. Team Probe Earthquakes at the Nanoscale

The research was spurred by an unusual phenomenon that showed the longer materials are in contact with one another, the stronger the resistance between them -- and the more violent and unstable the subsequent sliding is. Energy is stored over the time the materials are in contact and is then catastrophically released as an earthquake.

The team includes: Robert Carpick, a professor who chairs the Department of Mechanical Engineering and Applied Mechanics in Penn's School of Engineering and Applied Science; and Terry Tullis and David Goldsby, professors of geological science at Brown University. The experimental and modeling work was conducted by first author Qunyang Li, a postdoctoral researcher in Carpick's group, who has recently been appointed an associate professor in the School of Aerospace at Tsinghua University, China.

"If we can understand the fundamental physics," Tullis said, "then theories and equations based on that physics would have the capability of being extrapolated beyond the laboratory scale. Therefore we could use them with more confidence in all the earthquake modeling that's already being done."