报告地点:教学行政楼706会议室
报告时间:星期二,2015-05-19 16:00 - 17:30
报告人:Thorne Lay
报告人简介:
Large earthquakes on plate boundary megathrust faults exhibit substantial variations in rupture characteristics determined from seismic wave observations. We analyze large earthquakes with Mw ≥ 7.0 identified as being on megathrust faults, examining the source scaling behavior, spatial patterns, and depth-dependence of the source parameters. Depth-dependent characteristics have previously been recognized in the occurrence of shallow tsunami earthquakes with depleted short-period source spectra
报告题目: Depth Variations in Large Megathrust Earthquake Rupture Processes
Large earthquakes on plate boundary megathrust faults exhibit substantial variations in rupture characteristics determined from seismic wave observations. We analyze large earthquakes with Mw ≥ 7.0 identified as being on megathrust faults, examining the source scaling behavior, spatial patterns, and depth-dependence of the source parameters. Depth-dependent characteristics have previously been recognized in the occurrence of shallow tsunami earthquakes with depleted short-period source spectra and unusually long source durations, and in enhanced coherent short-period energy release from the deeper portions of megathrusts that fail in huge ruptures. There is little depth-dependence of stress drop or total radiated energy release for megathrust events that are not tsunami earthquakes, but there is systematic increase in relative short-period energy content and reduced high-frequency fall-off slope of the source spectra as depth increases. We consider the implications of the new source parameter data set for mechanisms operating in the megathrust environment.