Using Seismic Sensor Transfer Functions for High Fidelity Seismic Imaging

• US 20110222371A1
• Filed: 03/09/2010
• Published: 09/15/2011
• Est. Priority Date: 03/09/2010
• Status: Active Grant

• Current Assignee: WesternGeco LLC
• Original Assignee: WesternGeco LLC
• Inventors: Liu, Qinglin, Iranpour, Kambiz, Ronnow, Daniel
• Granted Patent: US 8,520,467 B2
• Time in Patent Office: Days
• US Class Current: 367/76
• CPC Class Codes: G01V 13/00 Manufacturing, calibrating, cleaning, or repairing instruments or devices covered by groups G01V1/00 – G01V11/00

Abstract

A technique includes deploying seismic sensors to perform a seismic survey and during the deployment of the seismic sensors, testing each of the seismic sensors to determine an associated sensor transfer function. The technique includes determining an associated operator to apply to seismic data acquired by each of the seismic sensors in the seismic survey based at least in part on a frequency dependent variation between the associated sensor transfer function and a nominal response for the seismic sensor. The technique includes processing the seismic data, including applying the associated operators to the seismic data.

Claims

1. A method comprising:

deploying seismic sensors to perform a seismic survey;

during the deployment of the seismic sensors, testing each of the seismic sensors to determine an associated sensor transfer function;

determining an associated operator to apply to seismic data acquired by each of the seismic sensors in the seismic survey based at least in part on a frequency dependent variation between the associated sensor transfer function and a nominal response for the seismic sensor; and

processing the seismic data, comprising applying the associated operators to the seismic data.

2. The method of claim 1, further comprising:

during the deployment of the seismic sensors, measuring seismic energy in connection with the survey, subsequently performing the determining of the associated operators and thereafter continuing with measuring of seismic energy in connection with the survey.

3. The method of claim 1, wherein seismic units are each associated with an independent seismic unit, and the determination of the associated sensor transfer function occurs within each seismic unit as part of a self test within the unit, the method further comprising:

for each seismic unit, communicating the seismic data and second data indicative of the determined associated sensor transfer operator from the seismic unit; and

recording the seismic data and the second data.

4. The method of claim 3, wherein the act of communicating the second data comprises communicating data indicative of at least one of the following:

the entire transfer function including frequency, magnitude and phase of the transfer function;

parameters that describe the transfer function;

parameters that describe the inverse of the transfer function; and

the entire inverse transfer function, including frequency, magnitude and phase of the inverse transfer function.

5. The method of claim 1, wherein the act of processing the seismic data comprises performing deconvolution in the frequency or time domain.

6. The method of claim 5, wherein the act of processing the seismic data further comprises compensating the seismic data before deconvolution for production variations or temperature variations.

7. The method of claim 6, wherein the act of compensating comprises at least one of the following:

scaling amplitudes indicated by the seismic data based on observed production variations or temperature variations; and

applying filters based on observed production variations or temperature variations.

8. The method of claim 1, further comprising:

identifying whether one or more of the transfer functions are outside of predetermined specifications and taking corrective action in response thereto.

9. The method of claim 8, wherein the act of taking corrective action comprises determining whether one or more of the identified transfer functions are correctly determined and using the identification of a transfer function that is outside of predetermined specification and correctly determined as a quality control indicator indicative of potential hardware failure.

10. The method of claim 8, wherein the act of taking corrective action comprises determining whether one or more of the identified transfer functions are incorrectly determined and substituting a reference transfer function for the identified transfer functions that are incorrectly determined in the processing of the seismic data.

11. The method of claim 1, wherein the seismic survey comprises an active seismic survey or a passive seismic survey.

12. A system comprising:

an interface to receive seismic data acquired by seismic sensors in a seismic survey and second data indicative of associated sensor transfer functions provided by the seismic sensors; and

a processor to;

determine an associated operator to apply to the seismic data acquired by each of the seismic sensors based at least in part on a frequency dependent variation between the associated sensor transfer function and a nominal response for the seismic sensor.

13. The system of claim 12, wherein the processor is further adapted to:

process the seismic data, including applying the associated operators to the seismic data.

14. The system of claim 12, wherein the seismic sensors comprise geophones, geophone accelerometers and/or hydrophones.

15. The system of claim 12, wherein the second data is indicative of at least one of the following:

the entire transfer function including frequency, magnitude and phase of the transfer function;

parameters that describe the transfer function;

parameters that describe the inverse of the transfer function; and

the entire inverse transfer function, including frequency, magnitude and phase of the inverse transfer function.

16. The system of claim 12, wherein the processor is adapted to perform deconvolution in the processing of the seismic data.

17. The system of claim 16, wherein the processor is adapted to compensate the seismic data before deconvolution for production variations or temperature variations.

18. The system of claim 12, wherein the processor is adapted to identify whether one or more the sensor transfer functions are outside of predetermined specifications and take corrective action in response thereto.

19. An article comprising a computer readable storage medium to store instructions that when executed by a computer cause the computer to:

receive seismic data acquired by seismic sensors in a seismic survey and second data provided by the seismic sensors indicative of associated sensor transfer functions determined by the seismic sensors; and

determine an associated operator to apply to the seismic data acquired by each of the seismic sensors based at least in part on a frequency dependent variations between the associated sensor transfer function and a nominal response for the seismic sensor; and

20. The article of claim 19, the storage medium storing instructions that when executed by the computer cause the computer to:

process the seismic data, including applying the associated operators to the seismic data.

21. The article of claim 19, wherein the seismic sensors comprise geophones, geophone accelerometers and/or hydrophones.

22. The article of claim 19, wherein the second data is indicative of at least one of the following:

the entire transfer function including frequency, magnitude and phase of the transfer function;

parameters that describe the transfer function;

parameters that describe the inverse of the transfer function; and

the entire inverse transfer function, including frequency, magnitude and phase of the inverse transfer function.

23. The article of claim 19, the storage medium storing instructions that when executed by the computer cause the computer to perform deconvolution in the processing of the seismic data.

24. The article of claim 23, the storage medium storing instructions that when executed by the computer cause the computer to compensate the seismic data before deconvolution for production variations or temperature variations.

25. The article of claim 19, the storage medium storing instructions that when executed by the computer cause the computer to identify whether one or more the sensor transfer functions are outside of predetermined specification and take corrective action in response thereto.