Abstract

Seismoacoustic Waves From Powerful Seismic Vibrators

B.M.Glinsky, V.V.Kovalevsky, M.S.Khairetdinov (Institute of Computational Mathematics and Mathematical Geophysics, SB RAS, Novosibirsk, Russia)

e-mail: gbm@opg.sscc.ru

The paper presents the results of experimental investigations of the processes of radiation and interaction of the acoustic and seismic fields generated by powerful vibroseismic sources of the low-frequency. The excitation effect of acoustic waves and subsequent induction of surface waves from powerful vibration sources at large distances between a radiator and a receiver. was detected experimentally. When the work of powerful seismic vibrators, an infrasonic acoustic wave is radiated simultaneously with seismic waves. In the presence of the near-surface sound channel, this wave can propagate to a distance of tens of kilometers and induce surface seismic waves. These waves are recorded by seismic receivers together with radiated seismic waves from vibrators. The propagation of acoustic waves of infrasonic frequencies (6-7 Hz) to a distance of 20 - 50 km is possible owing to the phenomenon of refraction of sonic waves in the atmosphere and appearance of near surface wave channel. The excitation mechanism of the surface seismic wave caused by the acoustic wave arrival at the recording point (acoustoseismic induction) was validated in mathematical simulation of the process.

Section : 6