HR: 1340h
AN: S53B-1108 [Abstracts]
TI: Obtaining Source Parameters from the Seismic Coda
AU: * Sens-Sch”nfelde, C
EM: sens-schoenfelder@uni-leipzig.de
AF: University of Leipzig
Institute of Geophysics and Geology, Talstraáe 35, Leipzig, 04103
Germany
AU: Wegler, U
EM: uli@rz.uni-leipzig.de
AF: University of Leipzig
Institute of Geophysics and Geology, Talstraáe 35, Leipzig, 04103
Germany
AU: Korn, M
EM: mikorn@rz.uni-leipzig.de
AF: University of Leipzig
Institute of Geophysics and Geology, Talstraáe 35, Leipzig, 04103
Germany
AB:
Forecasts crucially depend on history. A relyable knowledge of source parameters of past earthquakes is indispensible and
requires accurate estimates even for small events. We present a method to estimate the seismic moment of an earthquake from
its coda records. While previously existing methods were based on empirical description of the coda envelope our approach
utilizes an analytic solution of the radiative transfer equation. We can thus directly relate the energy level of the seismic
coda to the strength of the source expressed by the seismic moment. This approach significantly improves measurements of
source strength compared to estimates from direct phase amplitudes as local magnitudes. Especially for small earthquakes that
can not be waveform modeled because of scattering at small scale heterogeneities this technique can increase the accuracy of
information about the source.
We present the method and a case study that demonstrates the agreement between our estimates of the seismic moment and the
results from waveform modeling.
DE: 3285 Wave propagation (0689, 2487, 4275, 4455, 6934)
DE: 5144 Wave attenuation
DE: 7205 Continental crust (1219)
DE: 7215 Earthquake source observations (1240)
SC: Seismology [S]
MN: Fall Meeting 2005