EXPERIMENTAL ESTIMATION OF STRESS SENSITIVITY OF THE CRUST IN THE REGION OF LAKE BAIKAL, FROM ACTIVE VIBROSEISMIC MONITORING AND SOLID EARTH TIDE DATA

The paper presents an attempt to estimate the upper limit sensitivity of velocities and amplitudes of seismic waves to crustal stresses in a seismically active area of the Baikal rift on the basis of data from a short-term (10 days) active experiment using a 100-ton vibrator. Waves reflected from the Moho at a distance of 125 km from the source were recorded. The obtained series of wave travel time and amplitude variations were compared with tidal effects, which are presumed to cause periodic changes of internal stresses in the crust. The upper limit of velocity stress sensitivity showed to be about an order of magnitude higher than its indirect theoretical estimates. A technique is suggested for revealing statistical relationships between variations of wave propagation parameters.