Look-ahead VSP workflow that uses a time and depth variant Q to reduce uncertainties in depth estimation ahead of a drilling bit

A device comprising:

• one or more processors;
• and
• a non-transitory computer-readable storage medium coupled to the one or more processors and storing programming instructions for execution by the one or more processors, the programming instructions instructing the one or more processors to perform operations comprising:
• receiving seismic data acquired by at least one receiver of a geologic survey system configured to perform a geologic survey of a subterranean formation, wherein the seismic data is associated with reflected acoustic signals generated by a source of the geologic survey system;
• calculating a ground force signal by stacking the acoustic signals generated by the source;
• calculating, using the ground force signal, a time and depth variant quality factor (Q) of the subterranean formation, wherein the at least one receiver comprises a plurality of receivers, and wherein calculating, using the ground force signal, the time and depth variant quality factor (Q) of the subterranean formation comprises:
• calculating, using the ground force signal, a respective Q for a plurality of intervals in the subterranean formation, wherein the plurality of intervals are defined by a respective depth of the plurality of receivers within the subterranean formation;
• compensating, based on the time and depth variant Q, attenuation in the seismic data and
• using the compensated seismic data to generate seismic images of the subterranean formation, wherein the compensated seismic data is used in looking ahead of a drilling bit that is drilling a wellbore in the subterranean formation.

A non-transitory computer-readable medium storing instructions executable by a computer system to perform operations comprising:

• receiving seismic data acquired by at least one receiver of a geologic survey system configured to perform a geologic survey of a subterranean formation, wherein the seismic data is associated with reflected acoustic signals generated by a source of the geologic survey system;
• calculating a ground force signal by stacking the acoustic signals generated by the source;
• calculating, using the ground force signal, a time and depth variant quality factor (Q) of the subterranean formation, wherein the at least one receiver comprises a plurality of receivers, and wherein calculating, using the ground force signal, the time and depth variant quality factor (Q) of the subterranean formation comprises:
• calculating, using the ground force signal, a respective Q for a plurality of intervals in the subterranean formation, wherein the plurality of intervals are defined by a respective depth of the plurality of receivers within the subterranean formation;
• compensating, based on the time and depth variant Q, attenuation in the seismic data;
• and
• using the compensated seismic data to generate seismic images of the subterranean formation, wherein the compensated seismic data is used in looking ahead of a drilling bit that is drilling a wellbore in the subterranean formation.