Marine vibrator source acceleration and pressure

Patent metadata

Field	Value
Publication number	US-10436926-B2
Application number	US-201715619719-A
Country	US
Kind code	B2
Filing date	Jun 12, 2017
Priority date	Aug 17, 2016
Publication date	Oct 8, 2019
Grant date	Oct 8, 2019

Abstract

Marine survey data resulting from a first signal comprising a signal representing a flat spectral far-field pressure generated by a marine vibrator source swept over a frequency range according to a time function of motion such that acceleration of the marine vibrator source is a flat function in a frequency domain can be used to improve full waveform inversion. For example, full waveform inversion can be performed using the marine survey data received from the first signal and from a second signal generated by an impulsive seismic source to estimate a physical property of a subsurface location.

First claim

What is claimed is:

1. A system, comprising:
a marine survey source comprising a marine vibrator source; and
a controller, comprising hardware, coupled to the marine survey source, wherein the controller is configured to:
define a sweep length of the marine survey source over a broadband frequency range based on ambient noise and a selected target depth such that a sweep amplitude spectrum for a target reflection is above the ambient noise;
wherein the broadband frequency range includes frequencies sufficient for full waveform inversion.

2. The system of claim 1 , wherein the marine survey source comprises a plurality of marine vibrator sources.

3. The system of claim 2 , wherein the controller is configured to:
define a respective sweep length for each of the plurality of marine vibrator sources; and
define randomized start times for each of the plurality of marine vibrator sources.

4. The system of claim 1 , wherein the system further comprises:
recorded marine survey data resulting from signals generated by the marine survey source; and
processed marine survey data based on the recorded marine survey data without input from an impulsive seismic source.

5. The system of claim 1 , wherein the controller is further configured to define the sweep length based on a mechanical property of the marine survey source.

6. The system of claim 1 , wherein the marine survey source is maintained in a fixed position versus a plurality of towed streamers for recording signals generated by the marine survey source.

7. The system of claim 1 , wherein the controller is further configured to receive an input defining a desired sweep amplitude spectrum.

8. A method, comprising:
defining, by a controller comprising hardware coupled to a marine survey source comprising a marine vibrator source, a sweep length of the marine survey source over a broadband frequency range based on ambient noise and a selected target depth such that a sweep amplitude spectrum for a target reflection is above the ambient noise;
wherein the broadband frequency range includes frequencies sufficient for full waveform inversion.

9. The method of claim 8 , further comprising:
defining a sweep length for each of a plurality of marine vibrator sources including the marine survey source; and
defining randomized start times for each of the plurality of marine vibrator sources.

10. The method of claim 8 , further comprising defining the sweep length based on a mechanical property of the marine survey source.

11. The method of claim 8 , further comprising maintaining the marine survey source in a fixed position versus a plurality of towed streamers for recording signals generated by the marine survey source.

12. The method of claim 8 , further comprising receiving an input defining a desired sweep amplitude spectrum.

13. A non-transitory machine readable medium storing instructions executable by a processing resource to:
define a sweep length of a marine survey source, comprising a marine vibrator source, over a broadband frequency range based on ambient noise and a selected target depth such that a sweep amplitude spectrum for a target reflection is above the ambient noise;
wherein the broadband frequency range includes frequencies sufficient for full waveform inversion.

14. The medium of claim 13 , further comprising instructions to:
define a respective sweep length for each of a plurality of marine vibrator sources including the marine survey source; and
define randomized start times for each of the plurality of marine vibrator sources.

15. The medium of claim 13 , further comprising instructions to define the sweep length based on a mechanical property of the marine survey source.

16. The medium of claim 13 , further comprising instructions to maintain the marine survey source in a fixed position versus a plurality of towed streamers for recording signals generated by the marine survey source.

17. The medium of claim 13 , further comprising instructions to receive an input defining a desired sweep amplitude spectrum.

18. A method to manufacture a geophysical data product, the method comprising:
defining, by a machine, a sweep length of a marine survey source, comprising a marine vibrator source, over a broadband frequency range based on ambient noise and a selected target depth such that a sweep amplitude spectrum for a target reflection is above the ambient noise;
wherein the broadband frequency range includes frequencies sufficient for full waveform inversion;
obtaining, by the machine, geophysical data, wherein obtaining the geophysical data comprises receiving marine survey data from operation of the marine survey source with the sweep length;
processing, by the machine, the geophysical data to generate the geophysical data product; and
recording the geophysical data product on a non-transitory machine-readable medium.

19. The method of claim 18 , wherein processing the geophysical data comprises processing the geophysical data offshore or onshore.

Assignees

• Pgs Geophysical As

Inventors

• Söllner Walter F
• Orji Okwudili

Classifications

• G01V2210/62

  Physical property of subsurface · CPC title

• G01V2210/42

  Waveform, i.e. using raw or pre-filtered trace data · CPC title

• G01V3/083

  Controlled source electromagnetic [CSEM] surveying · CPC title

• G01V2003/086

  Processing · CPC title

• G01V1/28 Primary

  Processing seismic data, e.g. for interpretation or for event detection (G01V1/48 takes precedence) · CPC title