Focusing of Divergent Cylindrical Waves and the Prospects for Borehole Acoustics

This paper discusses prospects for borehole acoustics associated with the use of focused fields. The possibility of developing efficient borehole methods for testing nonlinear characteristics of natural deposited geological environments is studied. The potential of improving geotechnological processes using focused fields induced by extended borehole antennas is considered. The results of a pilot experiment on acoustic-field stimulation of underground leaching of less-common metals are presented.