Talks and Poster Presentations (without Proceedings-Entry):
P. Gerstoft, H. Yao, P. M. Shearer, C. Mecklenbräuker:
"Compressive sensing of the Tohoku-Oki Mw9.0 Earthquake: Frequency-dependent Rupture Modes";
Talk: American Geophysical Union Fall Meeting 2011,
San Francisco (CA), USA;
For this complex earthquake rupture, we seek a sparse set of spatio-temporal source locations consistent with the measurements. Compressive sensing (CS) is a technique for finding sparse signal representations to underdetermined linear measurement equations. We use CS to locate seismic sources during the rupture of the 2011 Tohoku-Oki Mw9.0 earthquake in Japan from teleseismic P waves recorded by an array of stations in the US. The seismic sources are located by minimizing the L2-norm of the difference between the observed and modeled waveforms penalized by the L1-norm of the seismic source vector. The resulting minimization problem is convex and can be solved efficiently. Our results show clear frequency-dependent rupture modes with high-frequency energy radiation dominant in the down-dip region and low-frequency radiation in the up-dip region, which may be caused by differences in rupture behavior (more intermittently or continuously) at the slab interface due to heterogeneous frictional properties.
Created from the Publication Database of the Vienna University of Technology.