Granted Patent B2

US 12,405,396 · App. 18/001,196 · Granted Sep 2, 2025

Inventors: Lu Liu (Beijing, CN); Fuhao Qin (Dhahran, SA); Yi Luo (Dhahran, SA); Yubing Li (Beijing, CN)

Assignee: SAUDI ARABIAN OIL COMPANY

G01V1/307

Abstract

Claims (72)

1. A method of determining a presence of hydrocarbons, comprising:

obtaining a surface seismic dataset,

wherein the surface seismic dataset comprises a plurality of seismic gathers; for each member of the plurality of seismic gathers, using a computer processor:

determining a redatumed gather for a target horizon based, at least in part, on the seismic gather,

wherein each redatumed gather comprises a plurality of redatumed traces,

determining a time window of the redatumed gather around the target horizon, and determining a spectrum of a portion within the time window,

determining a hydrocarbon indicator based, at least in part, on an amplitude of a higher-frequency portion of the spectrum and an amplitude of a lower-frequency portion of the spectrum of the plurality of seismic gathers;

determining, using the computer processor, a geographic map of values of the hydrocarbon indicator from the plurality of seismic gathers;

determining, using the computer processor, a presence of hydrocarbons based, at least in part, on at least one anomalous value on the geographic map;

planning a wellbore trajectory based, at least in part, on the map of the hydrocarbon indicator; and

drilling the wellbore trajectory.

2. The method of claim 1 ,

wherein determining the redatumed gather comprises simulating a reverse-time propagation of the seismic gather to a depth of the target horizon.

3. The method of claim 2 ,

wherein simulating the reverse-time propagation comprises solving a two-way wave propagation equation.

4. The method of claim 1 ,

wherein determining the hydrocarbon indicator comprises:

determining a ratio of the higher-frequency portion of the spectrum to the lower-frequency portion of the spectrum; and

determining a centroid frequency.

5. The method of claim 1 ,

wherein interpreting anomalous values comprises interpreting values that are greater, by a predetermined amount, than a mean of all of the hydrocarbon indicator values over the target horizon.

6. The method of claim 5 ,

wherein determining a geographic map of the values of the hydrocarbon indicator comprises determining a sum of the hydrocarbon indicator over a plurality of seismic gathers.

7. A non-transitory computer readable medium storing instructions executable by a computer processor, the instructions comprising functionality for:

receiving a surface seismic dataset,

wherein the surface seismic dataset comprises a plurality of seismic gathers;

for each member of the plurality of seismic gathers:

determining a redatumed gather for a target horizon based, at least in part, on the seismic gather,

wherein each redatumed gather comprises a plurality of redatumed traces,

determining a time window of the redatumed gather around the target horizon,

determining a spectrum of a portion within the time window, and

determining a hydrocarbon indicator based, at least in part, on an amplitude of a higher-frequency portion of the spectrum and an amplitude of a lower-frequency portion of the spectrum of the plurality of seismic gathers;

determining a geographic map of values of the hydrocarbon indicator from the plurality of seismic gathers;

determining a presence of hydrocarbons based, at least in part, on at least one anomalous value on the geographic map;

planning a wellbore trajectory based, at least in part, on the map of the hydrocarbon indicator; and

drilling the wellbore trajectory.

8. The non-transitory computer readable medium of claim 7 ,

wherein determining the redatumed gather comprises simulating reverse-time propagation of the seismic gather to a depth of the target horizon.

9. The non-transitory computer readable medium of claim 7 ,

wherein simulating reverse-time propagation comprises solving a two-way wave propagation equation.

10. The non-transitory computer readable medium of claim 7 ,

wherein determining the hydrocarbon indicator comprises:

determining a ratio of the higher-frequency portion of the spectrum to the lower-frequency portion of the spectrum; and

determining a centroid frequency.

11. The non-transitory computer readable medium of claim 7 ,

wherein interpreting anomalous values comprises interpreting values that are greater, by a predetermined amount, than a mean of all of the hydrocarbon indicator values over the target horizon.

12. The non-transitory computer readable medium of claim 11 ,

wherein determining a geographic map of the values of the hydrocarbon indicator comprises determining a sum of the hydrocarbon indicator over a plurality of seismic gathers.

13. A system comprising:

a seismic acquisition system; and

a seismic processor configured to:

receive a surface seismic dataset,

wherein the surface seismic dataset comprises a plurality of seismic gathers, for each member of the plurality of seismic gathers:

determine a redatumed gather for a target horizon based, at least in part, on the seismic gather,

wherein each redatumed gather comprises a plurality of redatumed traces;

determine a time window of the redatumed gather around the target horizon;

determine a spectrum of a portion within the time window;

determining a hydrocarbon indicator based, at least in part, on an amplitude of a higher-frequency portion of the spectrum and an amplitude of a lower-frequency portion of the spectrum of the plurality of seismic gathers;

determine a geographic map of values of the hydrocarbon indicator from the plurality of seismic gathers;

determine a presence of hydrocarbons based, at least in part, on at least one anomalous value on the geographic map;

planning a wellbore trajectory based, at least in part, on the map of the hydrocarbon indicator; and

drilling the wellbore trajectory.

14. The system of claim 13 ,

wherein determining the redatumed gather comprises simulating reverse-time propagation of the seismic gather to a depth of the target horizon.

15. The system of claim 13 ,

wherein simulating reverse-time propagation comprises solving a two-way wave propagation equation.

16. The system of claim 13 ,

wherein determining the hydrocarbon indicator comprises:

determining a ratio of the higher-frequency portion of the spectrum to the lower-frequency portion of the spectrum; and

determining a centroid frequency.

17. The system of claim 13 ,

wherein interpreting anomalous values comprises interpreting values that are greater, by a predetermined amount, than a mean of all of the hydrocarbon indicator values over the target horizon.

Assignments (3)

Continuity (1)

References Cited (29)