HR: 0800h
AN: NG41A-0144    [Abstracts]
TI: Instant Variations in Velocity and Attenuation of Seismic Waves in a Friable Medium Under a Vibrational Dynamic Loading
AU: * Geza, N
EM: geza@uiggm.nsc.ru
AF: Trofimuk Institute of Petroleum Geology and Geophysics SB RAS, pr. Acad. Koptuga, 3, Novosibirsk, 630090, Russian Federation
AU: Yushin, V
EM: yush@uiggm.nsc.ru
AF: Trofimuk Institute of Petroleum Geology and Geophysics SB RAS, pr. Acad. Koptuga, 3, Novosibirsk, 630090, Russian Federation
AB: Instant variations of the velocities and attenuation of seismic waves in a friable medium subjected to dynamic loading have been studied by new experimental techniques using a powerful seismic vibrator. The half-space below the operating vibrator baseplate was scanned by high-frequency elastic waves, and the recorded fluctuations were exposed to a stroboscopic analysis. It was found that the variations of seismic velocities and attenuation are synchronous with the external vibrational load but have phase shift from it. Instant variations of the seismic waves parameters depend on the magnitude and absolute value of deformation, which generally result in decreasing of the elastic-wave velocities. New experimental techniques have a high sensitivity to the dynamic disturbance in the medium and allow one to detect a weak seismic boundaries. The relaxation process after dynamic vibrational loading were investigated and the results of research are presented.
DE: 7219 Seismic monitoring and test-ban treaty verification
DE: 7223 Earthquake interaction, forecasting, and prediction (1217, 1242)
DE: 7290 Computational seismology
DE: 7294 Seismic instruments and networks (0935, 3025)
SC: Nonlinear Geophysics [NG]
MN: 2007 Fall Meeting