Patent ID: 7562740

Claim:
An acoustic borehole source for generating elastic waves through an earth formation at a designated location via a wall comprising: a first motorized reaction mass positioned along an axis of a sonde; and at least two pads, wherein each of said at least two pads are connected to said sonde and said first motorized reaction mass using a plurality of variable angle pushing rods to convert an axial motion into a radial motion so that said at least two pads generate elastic waves through the earth formation upon activation of said first motorized reaction mass as a result of impact of the pads against the wall; wherein the impedance of the acoustic borehole source may be controlled using said plurality of variable angle pushing rods; wherein activation of said first motorized reaction mass provides variable location adjustment for said at least two pads while said at least two pads are positioned at the designated location of the acoustic borehole source, such that said at least two pads generate elastic waves through the earth formation at multiple locations while at the designated location.