Image-domain 4D-binning method and system

Patent metadata

Field	Value
Publication number	US-9229122-B2
Application number	US-201313784112-A
Country	US
Kind code	B2
Filing date	Mar 4, 2013
Priority date	Mar 4, 2013
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

A method for increasing similarity between a base seismic survey and a monitor seismic survey of a same surveyed subsurface during a 4-dimensional (4D) project. The method includes receiving first seismic data associated with the base seismic survey; receiving second seismic data associated with the monitor seismic survey, wherein the monitor seismic survey is performed later in time than the base seismic survey; migrating the first and second seismic data to an image-domain; and calculating, with a processor, a set of decimating weights based on the migrated first and second seismic data in the image-domain, to maximize a similarity between the first seismic data and the second seismic data.

First claim

What is claimed is:

1. A method for increasing similarity between a base seismic survey and a monitor seismic survey of a same surveyed subsurface during a 4-dimensional (4D) project, the method comprising:
receiving first seismic data associated with the base seismic survey;
receiving second seismic data associated with the monitor seismic survey, wherein the monitor seismic survey is performed later in time than the base seismic survey;
migrating the first and second seismic data to an image-domain; and
calculating, with a processor, a set of decimating weights based on the migrated first and second seismic data in the image-domain, to maximize a similarity between the first seismic data and the second seismic data.

2. The method of claim 1 , further comprising:
applying the decimated weights to the first and second seismic data; and
generating an image of the surveyed subsurface based on the decimated weights and the first and second seismic data.

3. The method of claim 1 , further comprising:
splitting the first and second seismic data into overlapping spatio-temporal blocks; and
concatenating data corresponding to pairs of blocks from each of the first and second seismic data blocks to form a data vector.

4. The method of claim 3 , further comprising:
defining an ensemble of image points in the image-domain.

5. The method of claim 4 , further comprising:
calculating a first migration matrix for the first seismic data and a second migration matrix for the second seismic data.

6. The method of claim 5 , wherein an element of the first or second migration matrix is calculated based on Green functions that describe propagations (i) of a seismic wave from a seismic source to a point of the ensemble of image points and (ii) of a seismic wave from a seismic receiver to the point of the ensemble of points.

7. The method of claim 5 , further comprising:
combining the first and second migration matrices to obtain a net migration matrix.

8. The method of claim 7 , further comprising:
forming a vector of weights that have only diagonal elements equals to zero or one; and
calculating a residuals vector based on the net migration matrix, the vector of weights, and the data vector.

9. The method of claim 8 , further comprising:
defining a cost function based on the residuals vector and the vector of weights; and
minimizing the cost function to obtain the decimating data weights.

10. The method of claim 9 , further comprising:
multiplying the data vector with the decimating data weights to obtained weighted data.

11. The method of claim 10 , further comprising:
splitting the weighted data back into the spatio-temporal blocks.

12. The method of claim 11 , further comprising:
normalizing the weighted data by corresponding duplication numbers; and
writing a block number to a header of each data trace of the first and second seismic data.

13. The method of claim 1 , wherein one of the base and monitor surveys is a streamer based survey and the other of the base and monitor surveys is an ocean bottom node survey.

14. A computing device for increasing similarity between a base seismic survey and a monitor seismic survey of a same surveyed subsurface during a 4-dimensional (4D) project, the computing device comprising:
an interface configured to receive first seismic data associated with the base seismic survey and second seismic data associated with the monitor seismic survey, wherein the monitor seismic survey is performed later in time than the base seismic survey; and
a processor connected to the interface and configured to,
migrate the first and second seismic data to an image-domain, and
calculate a set of decimating weights based on the migrated first and second seismic data in the image-domain, to maximize a similarity between the first seismic data and the second seismic data.

15. The computing device of claim 14 , wherein the processor is further configured to:
apply the decimated weights to the first and second seismic data; and
generate an image of the surveyed subsurface based on the decimated weights and the first and second seismic data.

16. The computing device of claim 14 , wherein the processor is further configured to:
split the first and second seismic data into overlapping spatio-temporal blocks; and
concatenate data corresponding to pairs of blocks from each of the first and second seismic data blocks to form a data vector.

17. The computing device of claim 16 , wherein the processor is further configured to:
define an ensemble of image points in the image-domain,
calculate a first migration matrix for the first seismic data and a second migration matrix for the second seismic data,
combine the first and second migration matrices to obtain a net migration matrix,
form a vector of weights that have only diagonal elements equals to zero or one, and
calculate a residuals vector based on the net migration matrix, the vector of weights, and the data vector.

18. The computing device of claim 17 , wherein the processor is further configured to:
define a cost function based on the residuals vector and the vector of weights,
minimize the cost function to obtain the decimating data weights,
multiply the data vector with the decimating data weights to obtained weighted data,
split the weighted data back into the spatio-temporal blocks, and
normalize the weighted data by corresponding duplication numbers.

19. The computing device of claim 14 , wherein one of the base and monitor surveys is a streamer based survey and the other of the base and monitor surveys is an ocean bottom node survey.

20. A non-transitory computer readable medium including computer executable instructions, wherein the instructions, when executed by a computer, implement a method for increasing similarity between a base seismic survey and a monitor seismic survey of a same surveyed subsurface during a 4-dimensional (4D) project, the method comprising:
receiving first seismic data associated with the base seismic survey;
receiving second seismic data associated with the monitor seismic survey, wherein the monitor seismic survey is performed later in time than the base seismic survey;
migrating the first and second seismic data to an image-domain; and
calculating, with a processor, a set of decimating weights based on the migrated first and second seismic data in the image-domain, to maximize a similarity between the first seismic data and the second seismic data.

Assignees

• Cggveritas Services Sa

Inventors

• Haacke Ross

Classifications

• G01V2210/51

  Migration · CPC title

• G01V2210/612

  Previously recorded data, e.g. time-lapse or 4D · CPC title

• G01V1/308 Primary

  Time lapse or 4D effects, e.g. production related effects to the formation (fluid flow per se E21B47/00) · CPC title

• G01V1/366

  by correlation of seismic signals · CPC title