Abstract: A sonic well logging system and apparatus for determination of seismic wave velocities from a seismic wave propagating in a subterranean formation about a wellbore. The system includes the process of imparting a seismic wave into the subterranean formation about the wellbore, and receiving the seismic wave after it has interacted with the subterranean formation at a plurality of semismic receivers positioned in the wellbore. The seismic waves are transformed at each of the seismic receivers into a seismic signal and these signals nonlinearly staked for a selected position in the wellbore to generate a velocity spectrum of seismic wave velocities. Coherency peaks are then selected from the velocity spectrum with each coherency peak having associated therewith a unique seismic wave velocity, such as P-wave, S-wave, tube wave and the like.

Abstract: A sonic well logging system and apparatus for determination of seismic wave velocities from a seismic wave propagating in a subterranean formation about a wellbore. The system includes the process of imparting a seismic wave into the subterranean formation about the wellbore, and receiving the seismic wave after it has interacted with the subterranean formation at a plurality of seismic receivers positioned in the wellbore. The seismic waves are transformed at each of the seismic receivers into a seismic signal and these signals nonlinearly stacked for a selected position in the wellbore to generate a velocity spectrum of seismic wave velocities. Coherency peaks are then selected from the velocity spectrum with each coherency peak having associated therewith a unique seismic wave velocity, such as P-wave, S-wave, tube wave and the like.