HR: 0800h
AN: S51B-1015    [Abstracts]
TI: Frequency-Dependent Local Magnitude Scales for the Central U.S.
AU: * Miao, Q
EM: qingmiao@memphis.edu
AF: Center for Earthquake Research and Information, University of Memphis, 3892 Central Avenue, Memphis, TN 38152 United States
AU: Langston, C A
EM: clangstn@memphis.edu
AF: Center for Earthquake Research and Information, University of Memphis, 3892 Central Avenue, Memphis, TN 38152 United States
AB: Frequency-dependent local magnitude scales were developed for the study of seismic wave propagation and attenuation with frequency in the central U.S. within 600 km distance from the source. This is done by empirically modeling narrow frequency band filtered ground motion data from the CERI Cooperative Network and the United States National Seismograph Network (USNSN) to derive source size (local magnitude) and distance attenuation relationships for seismic wave propagation. The frequencies selected for this study are between 0.1 and 10.0 Hz. The obtained distance-correction functions show that the propagation of seismic waves at frequencies below 1.0 Hz do not attenuation with distance. Results show that the currently used M_D scale may measure a narrow frequency band of seismic waves, while M_L scale measures a relatively wide frequency band, which explained the differences between the M_D and M_L values in the central U.S.
DE: 7205 Continental crust (1219)
DE: 7212 Earthquake ground motions and engineering seismology
DE: 7230 Seismicity and tectonics (1207, 1217, 1240, 1242)
SC: Seismology [S]
MN: Fall Meeting 2005