HR: 0800h
AN: S21A-0269    [Abstracts]
TI: Progress Towards Near-Realtime Seismic Moment Tensors at the Alaska Earthquake Information Center
AU: * Ratchkovski, N
EM: natasha@giseis.alaska.edu
AF: Geophysical Institute, University of Alaska Fairbanks, 903 Koyukuk Drive, Fairbanks, AK 99775
AU: Hansen, R
EM: roger@giseis.alaska.edu
AF: Geophysical Institute, University of Alaska Fairbanks, 903 Koyukuk Drive, Fairbanks, AK 99775
AB: A near-realtime seismic moment tensor inversion routine has been operational at the Alaska Earthquake Information Center (AEIC) in a test mode for over a year. The AEIC real-time earthquake detection system, based on the Antelope software package, triggers the automatic moment-tensor inversion routine. It is based on a software package developed at the Berkeley Seismological Laboratory and performs a time domain inversion of three-component seismic data for the seismic moment tensor. We use a library of precalculated Green's functions for a suite of regional velocity models and a range of source depths (from 5 to 200 km with 5 km interval) to compute synthetic seismograms. The resulting moment tensor inversion information is distributed via the web. The Alaska seismic network in its current configuration includes 45 broad-band sites. Stable inversion results can be obtained for events with magnitude 4.0 and greater in the network core area (southern and central Alaska) and 4.5 and greater in the rest of the state including the Aleutian Islands. We will present a catalog of nearly 200 regional moment tensor solutions for Alaska and Aleutian Islands starting from October, 2002 through the present including, the 2002 Denali Fault earthquake sequence.
DE: 7230 Seismicity and seismotectonics
DE: 7294 Instruments and techniques
DE: 7215 Earthquake parameters
SC: Seismology [S]
MN: 2004 AGU Fall Meeting