Seismic wave emitting system for e.g. oil well, has active part for generating seismic waves and formed by active elements arranged outside of casing joint, and movable source inducing magnetic field and disposed within joint

摘要

The system has a set of casing joints (1) forming a casing (10) and designed for passing a magnetic field, and an active part for generating seismic waves, where the active part is formed by active elements e.g. magnetostrictive material, arranged outside of one of the casing joints. A movable source i.e. reel (8), inducing the magnetic field is disposed within the joint. The elements are constituted by bars (4) arranged on a perimeter of the joint, and arranged parallel to a casing axis (A). An independent claim is also included for a method for emitting seismic waves.