Detecting near-surface structures

A system, comprising:

• a distributed acoustic sensing (DAS) cable positioned in a spiral configuration layout around a drilling rig, wherein the drilling rig comprises one or more pieces of drilling rig equipment, and the DAS cable comprises a fiber-optic cable;
• and
• a control system communicably coupled to the DAS cable and configured to perform operations comprising:
• interrogating, using a plurality of distributed fiber-optic sensing (DFOS) laser pulses, the DAS cable during a drilling operation of the drilling rig;
• receiving a plurality of backscattered laser pulses from the DAS cable after the DAS cable is interrogated using the plurality of DFOS laser pulses;
• and
• determining, based on the plurality of backscattered laser pulses, a respective location of each of one or more anomalies in sub-terrain around the drilling rig, the determining comprising:
• determining, based on the plurality of backscattered laser pulses, one or more gathers of seismic traces;
• and
• determining, based on the one or more gathers of seismic traces and using frequency-wavenumber (F-K) analysis, the respective location of each of the one or more anomalies.

A method, comprising:

• positioning a distributed acoustic sensing (DAS) cable in a spiral configuration layout around a drilling rig, wherein the drilling rig comprises one or more pieces of drilling rig equipment, and the DAS cable comprises a fiber-optic cable;
• interrogating, using a plurality of distributed fiber-optic sensing (DFOS) laser pulses, the DAS cable during a drilling operation of the drilling rig;
• receiving a plurality of backscattered laser pulses from the DAS cable after the DAS cable is interrogated using the plurality of DFOS laser pulses;
• and
• determining, based on the plurality of backscattered laser pulses, a respective location of each of one or more anomalies in sub-terrain around the drilling rig, the respective location comprising a respective azimuth and offset of each of the one or more anomalies, and the respective offset is with respect to the drilling rig.

A method, comprising:

• positioning a distributed acoustic sensing (DAS) cable in a spiral configuration layout around a drilling rig, the positioning comprising positioning the DAS cable in the spiral configuration layout around the drilling rig and in a star shape configuration layout, and the star shape configuration layout comprises a plurality of radial paths that intersect at the drilling rig, wherein the drilling rig comprises one or more pieces of drilling rig equipment, and the DAS cable comprises a fiber-optic cable;
• interrogating, using a plurality of distributed fiber-optic sensing (DFOS) laser pulses, the DAS cable during a drilling operation of the drilling rig;
• receiving a plurality of backscattered laser pulses from the DAS cable after the DAS cable is interrogated using the plurality of DFOS laser pulses;
• and
• determining, based on the plurality of backscattered laser pulses, a respective location of each of one or more anomalies in sub-terrain around the drilling rig.

A system, comprising:

• a distributed acoustic sensing (DAS) cable positioned in a spiral configuration layout around a drilling rig, wherein the drilling rig comprises one or more pieces of drilling rig equipment, and the DAS cable comprises a fiber-optic cable;
• and
• a control system communicably coupled to the DAS cable and configured to perform operations comprising:
• interrogating, using a plurality of distributed fiber-optic sensing (DFOS) laser pulses, the DAS cable during a drilling operation of the drilling rig;
• receiving a plurality of backscattered laser pulses from the DAS cable after the DAS cable is interrogated using the plurality of DFOS laser pulses;
• and
• determining, based on the plurality of backscattered laser pulses, a respective location of each of one or more anomalies in sub-terrain around the drilling rig, the respective location comprising a respective azimuth and offset of each of the one or more anomalies, and the respective offset is with respect to the drilling rig.

A system, comprising:

• a distributed acoustic sensing (DAS) cable positioned in a spiral configuration layout around a drilling rig, the DAS cable being positioned in the spiral configuration layout around the drilling rig and in a star shape configuration layout, and the star shape configuration layout comprises a plurality of radial paths that intersect at the drilling rig, wherein the drilling rig comprises one or more pieces of drilling rig equipment, and the DAS cable comprises a fiber-optic cable;
• and
• a control system communicably coupled to the DAS cable and configured to perform operations comprising:
• interrogating, using a plurality of distributed fiber-optic sensing (DFOS) laser pulses, the DAS cable during a drilling operation of the drilling rig;
• receiving a plurality of backscattered laser pulses from the DAS cable after the DAS cable is interrogated using the plurality of DFOS laser pulses;
• and
• determining, based on the plurality of backscattered laser pulses, a respective location of each of one or more anomalies in sub-terrain around the drilling rig.