# US 11,079,507 B2 · Passive seismic imaging > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,507 B2 - Document ID: US11079507B2 - Status: Granted - Kind: B2 - Application number: 16/671,300 - Filed: 2019-11-01 - Published: 2020-05-14 - Granted: 2021-08-03 - Earliest claimed: 2019-11-01 - Assignees: BP Exploration Operating Company Limited - Applicants: BP Exploration Operating Company Limited - Inventors: Zhongmin Song; York Zheng - Web page: https://patentgrep.com/patent/US11079507B2 ## CPC - G01V 1/301: {for determining seismic cross-sections or geostructures} - G01V 1/303: {for determining velocity profiles or travel times} - G01V 1/307: {for determining seismic attributes, e.g. amplitude, instantaneous phase or frequency, reflection strength or polarity} - G01V 1/325: {Transforming one representation into another} - G01V 1/345: {Visualisation of seismic data or attributes, e.g. in 3D cubes} - G01V 1/38: specially adapted for water-covered areas (G01V1/28 takes precedence) - G01V 2210/123: Passive source, e.g. microseismics - G01V 2210/43: Spectral - G01V 2210/612: Previously recorded data, e.g. time-lapse or 4D - G01V 2210/614: Synthetically generated data - G01V: GEOPHYSICS; GRAVITATIONAL MEASUREMENTS; DETECTING MASSES OR OBJECTS; TAGS (means for indicating the location of accidentally buried, e.g. snow-buried, persons A63B29/02) ## Abstract A virtual seismic shot record is generated based at least in part on seismic interferometry of the passive seismic data. Then, a frequency bandwidth of the virtual seismic shot record is determined, wherein the frequency bandwidth comprises a plurality of frequencies. The virtual seismic shot record is transformed into a frequency-dependent seismic shot record based on a first frequency of the plurality of frequencies. Further, a phase shift is applied to the frequency-dependent seismic shot record. A first velocity model is generated from the phase shifted frequency-dependent seismic shot record. A second velocity model may be generated using full-waveform inversion (FWI). One or more depth slices are identified from the second velocity model. A seismic image is generated based on the one or more depth slices for use with seismic exploration above a region of subsurface including a hydrocarbon reservoir and containing structural features conducive to a presence, migration, or accumulation of hydrocarbons. ## Claims ### Claim 1 A method, comprising: generating a virtual seismic shot record based at least in part on seismic interferometry of passively acquired seismic data; determining a frequency bandwidth of the virtual seismic shot record, wherein the frequency bandwidth comprises a plurality of frequencies; transforming the virtual seismic shot record into a frequency-dependent seismic shot record based on a first frequency of the plurality of frequencies; applying a phase shift to the frequency-dependent seismic shot record to generate a phase-shifted frequency dependent seismic shot record; generating a first velocity model from the phase shifted frequency-dependent seismic shot record; generating a second velocity model using full-waveform inversion (FWI) based on the first velocity model; identifying a depth slice from the second velocity model; and generating a seismic image based at least in party on the depth slice for use with seismic exploration above a region of subsurface comprising a hydrocarbon reservoir and containing structural features conducive to a presence, migration, or accumulation of hydrocarbons. ### Claim 2 (depends on 1) The method of claim 1, comprising using discrete Fourier transform to obtain the frequency-dependent seismic shot record. ### Claim 3 (depends on 1) The method of claim 1, comprising converting time picks to a phase part of the frequency domain data to obtain the frequency-dependent seismic shot record. ### Claim 4 (depends on 1) The method of claim 1, comprising selecting, as the first velocity model, a velocity value based on an approximate move-out of the virtual seismic shot record. ### Claim 5 (depends on 1) The method of claim 1, comprising selecting, as the first velocity model, a velocity value based on a mean value of a previously run phase velocity tomography model. ### Claim 6 (depends on 1) The method of claim 1, wherein the depth slice corresponds to a respective frequency of the plurality of frequencies. ### Claim 7 (depends on 1) The method of claim 1, comprising transforming the virtual seismic shot record into an additional frequency-dependent shot record based on a second frequency of the plurality of frequencies; and identifying an additional depth slice based at least in part on the additional frequency-dependent shot record. ### Claim 8 (depends on 7) The method of claim 7, comprising generating a seismic image based on the depth slice and the additional depth slice for use with seismic exploration above a region of subsurface comprising a hydrocarbon reservoir and containing structural features conducive to a presence, migration, or accumulation of hydrocarbons. ### Claim 9 (depends on 8) The method of claim 8, comprising combining the seismic image with an additional seismic image generated based at least in part on active seismic data to generate a supplemental seismic image. ### Claim 10 (depends on 9) The method of claim 9, wherein a first depth portion of the supplemental seismic image is based on the seismic image, and a second depth portion of the supplemental seismic image is based on the additional seismic image. ### Claim 11 One or more tangible, non-transitory, machine-readable media comprising instructions configured to cause a processor to: generate a virtual seismic shot record based at least in part on seismic interferometry of passively acquired seismic data; determine a frequency bandwidth of the virtual seismic shot record, wherein the frequency bandwidth comprises a plurality of frequencies; transform the virtual seismic shot record into a frequency-dependent seismic shot record based on a first frequency of the plurality of frequencies; apply a phase shift to the frequency-dependent seismic shot record to generate a phase-shifted frequency dependent seismic shot record; generate a first velocity model from the phase shifted frequency-dependent seismic shot record; generate a second velocity model using full-waveform inversion (FWI) based on the first velocity model; identify one or more depth slices from the second velocity model; and generate a seismic image based on the one or more depth slices for use with seismic exploration above a region of subsurface comprising a hydrocarbon reservoir and containing structural features conducive to a presence, migration, or accumulation of hydrocarbons. ### Claim 12 (depends on 11) The one or more machine-readable media of claim 11, wherein the processor is configured to: generate an additional seismic image based on additional passive seismic data; and provide an indication based on a comparison between the seismic image and the additional seismic image. ### Claim 13 (depends on 12) The one or more machine-readable of claim 12, wherein the indication comprises a position location of the hydrocarbons. ### Claim 14 (depends on 12) The one or more machine-readable of claim 12, wherein the indication comprises a position of a subsurface hazard. ### Claim 15 (depends on 12) The one or more machine-readable media of claim 12, comprising instructions configured to cause a processor to transmit the indication for display on a display. ### Claim 16 (depends on 12) The one or more machine-readable media of claim 12, comprising instructions configured to cause the processor to convert time picks obtained by a phase velocity travel-time picking code to the phase part of the frequency domain data to obtain the frequency-dependent seismic shot record. ### Claim 17 (depends on 12) The one or more machine-readable media of claim 12, wherein the first velocity model comprises a velocity value that is selected based on a mean value of a previously run phase velocity tomography model. ### Claim 18 A device, comprising: a processor configured to: generate a virtual seismic shot record based at least in part on seismic interferometry of the passively acquired seismic data; determine a frequency bandwidth of the virtual seismic shot record, wherein the frequency bandwidth comprises a plurality of frequencies; transform the virtual seismic shot record into a frequency-dependent seismic shot record based on a first frequency of the plurality of frequencies; apply a phase shift to the frequency-dependent seismic shot record to generate a phase-shifted frequency dependent seismic shot record; generate a first velocity model from the phase shifted frequency-dependent seismic shot record; generate a second velocity model using full-waveform inversion (FWI) based on the first velocity model; identify one or more depth slices from the second velocity model; and generate a seismic image based on the one or more depth slices for use with seismic exploration above a region of subsurface comprising a hydrocarbon reservoir and containing structural features conducive to a presence, migration, or accumulation of hydrocarbons. ### Claim 19 (depends on 18) The device of claim 18, wherein the processor is configured to provide an indication of a position of hydrocarbon deposits. ### Claim 20 (depends on 18) The device of claim 18, wherein the processor is configured to: generate an additional seismic image based on additional passive seismic data; provide an indication of a change in a formation based on a comparison between the seismic image and the additional seismic image.