Seismic wave generator and method of geophysical prospecting using the same

Abstract

A device for generating seismic waves in the earth employs an elongated open-ended barrel having its closed end adjustably supported on a base plate for inclinations with respect to the base from about 15.degree. to 30.degree. is also rotatable about an axis normal to the base. A cardboard tube with an interior waterproof coating and transverse dimensions complementary to the barrel is placed into the barrel so that its lower end is spaced from the closed end of the barrel. An explosive charge and a detonator are placed between the end of the barrel and the end of the tube. When the charge is detonated the resulting recoil impacts the base against the earth generating both compressional and shear waves which are recorded at a distance by a transverse seismometer. The barrel is then rotated through 180.degree. about an axis normal to the base and a second firing is made, generating compressional waves with the same phase and magnitude as the first firing and shear waves of equal magnitude but opposite phase. The seismometer records the waves from this second firing and the two recordings are summed to eliminate the shear wave components and subtracted to eliminate the compressional wave components.

Dependencies are inferred from the claim text.