Patent ID: 8132641

Claim:
An apparatus for directionally generating seismic waves comprising: an elongate hollow casing having opposing first and second ends, the hollow casing substantially vertically oriented with respect to the surface of the earth and at least partially placed in the earth with the second end in the earth and the first end at or above the surface of the earth and without earth substantially within the hollow casing; a striking member including a shaft, a striking end at one end of the shaft, and an earth contacting end at the opposing end of the shaft, the shaft of the striking member extending through the elongate hollow casing such that the earth contacting end protrudes past the second end of the hollow casing and the striking end protrudes past the first end of the hollow casing without contacting the hollow casing, the earth contacting end of the striking member located proximate to the hollow casing second end, the shaft substantially prevented from contacting the earth by the hollow casing; and a spacing member positioned between the shaft of the striking member and the hollow casing, the spacing member maintaining the hollow casing and the shaft in a slidable spaced relation to each another.