METHOD OF ESTIMATING CHANGE IN STRESS CONDITION OF GEOLOGICAL ENVIRONMENT Russian patent published in 2011 - IPC G01V1/00 

FIELD: physics.

SUBSTANCE: distant earthquakes are used as a seismic wave source and three-component seismic recorders placed on the measuring site are used as receivers. The time of the first arrival of a longitudinal wave is recorded at component z of each seismic record from one earthquake. The time interval for seismic recording is selected, for example 4 seconds. Mode-converted energy is calculated on x and y components. Energy is accumulated for each of the seismic records from a given earthquake. Mode-converted energy from the next earthquakes continues to be summed up until stable amplitude-spatial non-uniformities appear in the mode-converted energy distribution. Said non-uniformities reflect the structure of the area under the measurement site and determine a quasi-stable level of background stress. Further, monitoring observations are conducted, as a result of which a series of similar structures are obtained in the mode-converted energy distribution. Change in the stress condition of the geological environment is determined from the value of deviation from the level of background stress. Relative danger of change in the stress condition of the geological environment under the measurement site is determined from the value of the amplitude of stable fluctuation of distribution of mode-converted waves - target useful signal. The target useful signal is a colour gamma.

EFFECT: high reliability and rapidness of estimating change in stress condition of the geological environment.

2 cl, 8 dwg