Seismic data least-square migration method and device

Patent metadata

Field	Value
Publication number	US-10324207-B2
Application number	US-201615337561-A
Country	US
Kind code	B2
Filing date	Oct 28, 2016
Priority date	Nov 2, 2015
Publication date	Jun 18, 2019
Grant date	Jun 18, 2019

Abstract

Computing device, computer instructions and method for calculating an image of a subsurface based on least square migration and image de-convolution using a matching operator F. The method includes receiving seismic data d; computing a first image m of the subsurface based on the seismic data d; computing a second image h of the subsurface based on the first image m; applying a transform operation to the first and second images m and h to obtain a first transform of the first image and a second transform of the second image; calculating the matching operator F by matching the first transform of the first image to the second transform of the second image; and generating an updated image m updated of the subsurface based on the matching operator F and the first transform of the first image.

First claim

What is claimed is:

1. A method for generating an image of a subsurface explored by a seismic survey based on least square migration and image de-convolution using a matching operator F, the method comprising:
receiving seismic data d acquired for the subsurface during the seismic survey;
computing a first image m of the subsurface based on the seismic data d;
computing a second image h of the subsurface based on the first image m;
applying a transform operation to the first and second images m and h to obtain a first transform of the first image and a second transform of the second image;
calculating the matching operator F by matching the first transform of the first image to the second transform of the second image; and
generating an updated image m updated of the subsurface based on the matching operator F and the first transform of the first image,
wherein the updated image of the subsurface is useable to determine whether oil and/or gas reservoirs are present in the subsurface.

2. The method of claim 1 , wherein the transform operation is a dip decomposition.

3. The method of claim 2 , wherein the dip decomposition decomposes the first and second images m and h, in an image domain, according to dip volumes V i of the subsurface, the first transform of the first image is a first dip decomposed image m i , the second transform of the second image is a second dip decomposed images h i , where “i” is an index, and the method further comprises:
calculating different matching operators F i for each pair of the first and second dip decomposed images m i and h i that have the same index i.

4. The method of claim 3 , further comprising:
calculating an updated image component m updated i for each pair of first and second dip decomposed images m i and h i that have the same index i by applying the different matching operator F i to a corresponding first dip decomposed image m i .

5. The method of claim 4 , further comprising:
constructing the updated image m updated using the updated image components m updated i corresponding to dip volumes V i .

6. The method of claim 1 , wherein the step of computing a second image h comprises:
applying a demigration operator L to the first image m followed by applying a migration operator L H , wherein the migration operator is an adjoint of the demigration operator,
wherein the demigration operator L and the migration operator L H transform an object from an image space to a data space and vice versa, respectively.

7. The method of claim 1 , wherein the step of calculating further comprises:
applying a cost function in an image space, between the first image m and the second image h, to calculate the matching operator F.

8. The method of claim 1 , wherein the seismic data d is in a data space and the first and second images m and h are in image space, which is different from the data space.

9. The method of claim 1 , wherein the transform operation is a Fourier transform, curvelet transform, tau-p transform or wavelet transform.

10. The method of claim 1 , wherein the first transform of the first image is in a same domain as the first image m.

11. The method of claim 1 , wherein the first transform of the first image is in a domain different from the first image m.

12. The method of claim 1 , further comprising:
splitting the seismic d or the first image m into subsets, and calculating plural pre-stack images p i corresponding to the subsets;
stacking a selected pre-stack range from the pre-stack images p i to generate a stack image s;
de-migrating the stack image s and migrating an output of the de-migrating to produce pre-stack re-migrated images n i ;
calculating the matching operator F by matching the pre-stack re-migrated images n i with the stack image s; and
applying the matching operator F to the pre-stack images p i to obtain updated pre-stack images.

13. The method of claim 1 , wherein at least one of the first and second images is denoised prior to calculating the matching operator F.

14. A computing device for generating an image of a subsurface explored by a seismic survey based on least square migration and image de-convolution using a matching operator F, the computing device comprising:
an interface for receiving seismic data d acquired for the subsurface during the seismic survey; and
a processor connected to the interface and configured to,
compute a first image m of the subsurface based on the seismic data d;
compute a second image h of the subsurface based on the first image m;
apply a transform operation to the first and second images m and h to obtain a first transform of the first image and a second transform of the second image;
calculate the matching operator F by matching the first transform of the first image to the second transform of the second image; and
generate an updated image m updated of the subsurface based on the matching operator F and the first transform of the first image
wherein the updated image of the subsurface is useable to determine whether oil and/or gas reservoirs are present in the subsurface.

15. The computing device of claim 14 , wherein the transform operation is a dip decomposition.

16. The computing device of claim 15 , wherein the dip decomposition decomposes the first and second images m and h, in an image domain, according to dip volumes V i of the subsurface, the first transform of the first image is a first dip decomposed image m i , the second transform of the second image is a second dip decomposed images h i , where “i” is an index, and the processor is further configured to:
calculate different matching operators F i for each pair of the first and second dip decomposed images m i and h i that have the same index i.

17. The computing device of claim 16 , wherein the processor is further configured to:
calculate an updated image component m updated i for each pair of first and second dip decomposed images m i and h i that have the same index i by applying the different matching operator F i to a corresponding first dip decomposed image m i .

18. The computing device of claim 17 , wherein the processor is further configured to:
construct the updated image m updated using the updated image components m updated i corresponding to dip volumes V i .

19. The computing device of claim 14 , wherein the processor is further configured to:
apply a demigration operator L to the first image m followed by applying a migration operator L H , wherein the migration operator is an adjoint of the demigration operator,
wherein the demigration operator L and the migration operator L H transform an object from an image space to a data space and vice versa, respectively.

20. A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed by a processor, implement instructions for generating an image of a subsurface explored by a seismic survey based on least square migration and image de-convolution using a matching operator F, the instructions controlling the processor to:
receive seismic data d acquired for the subsurface during the seismic survey;
compute a first image m of the subsurface based on the seismic data d;
compute a second image h of the subsurface based on the first image m;
apply a transform operation to the first and second images m and h to obtain a first transform of the first image and a second transform of the second image;
calculate the matching operator F by matching the fir

Assignees

• Cgg Services Sa
• Cgg Services Sas

Inventors

• Khalil Adel
• Hoeber Henning
• Hembd Jeshurun
• Gomes Adriano
• Poole Gordon
• Perrone Francesco
• Casasanta Lorenzo
• Roberts Graham
• Ratcliffe Andrew

Classifications

• G01V2210/51

  Migration · CPC title

• G01V1/364

  Seismic filtering (G01V1/37 takes precedence) · CPC title

• G01V1/362

  Effecting static or dynamic corrections; Stacking · CPC title

• G01V2210/512

  Pre-stack · CPC title

• G01V1/301

  for determining seismic cross-sections or geostructures · CPC title