Nonlinear seismics and the acoustic action on the oil recovery from an oil pool

At the first stage of seismic action, the attenuation of acoustic waves in real (porous, creviced) rocks is always related to the energy pumping to high-frequency (ultrasonic) modes, and only at the next stage are these waves converted into chaotic thermal oscillations, so that the entire phenomenon refers to a basic problem of nonlinear seismics. Several physical phenomena related to the excitation of ultrasound and the corresponding transformations of the wave spectrum (including the dry friction in contacts, the instability of viscoelastic oscillations, the seismic energy pumping to the rotational modes, and the resonance of gas bubbles in natural oil) are considered in relation to the development of vibroseismic methods of acting upon a producing oil pool. The results of experiments on the ultrasound-stimulated water displacement of natural (gas-saturated) oil from a porous medium are presented, in which the oil recovery reached up to 90%.