[ MOBILE ACOUSTIC SIGNAL DETECTING HYDROPHONES, ] HIGH ENERGY IMPULSIVE ACOUSTIC UNITS, AND [ APPARATUS FOR OPERATING ] [ HYDROPHONES AND ] ACOUSTIC UNITS

GEOPHYSICAL PROSPECTING AND SURVEYING SERVICES FOR THE OIL, GAS AND MINING INDUSTRIES FEATURING THE USE OF POWERFUL ACOUSTICAL IMPULSES IN A BOREHOLE AND FOR RECEIVING AND FOR RECORDING THE RESULTING SIGNALS