Publication Date:
2007-04-01
Description:
The source parameters of 523 aftershocks (0.512 Hz) fall-off of the acceleration source spectra by computing the kappa parameter. The seismic moments obtained range between 1.05X10 (super 14) and 2.41X10 (super 17) N m, whereas the Brune stress drops are between 0.002 and 40 MPa. The kappa value varies between 0.00 and 0.08 sec, indicating a decay of the acceleration level at the higher frequency part of the spectrum greater than that assumed by the omega (super -2) model. Both the stress drop and the kappa parameter show the tendency of increasing with aftershock magnitude. No evidence of self-similarity breakdown is observed between the source radius and M (sub 0) . Finally, both the seismic moment and the moment magnitude are compared with the local magnitude to derive new moment-magnitude relationships for the area.
Print ISSN:
0037-1106
Electronic ISSN:
1943-3573
Topics:
Geosciences
,
Physics