Processing seismic data

Patent metadata

Field	Value
Publication number	US-9341726-B2
Application number	US-201013259639-A
Country	US
Kind code	B2
Filing date	Feb 24, 2010
Priority date	Mar 27, 2009
Publication date	May 17, 2016
Grant date	May 17, 2016

Abstract

A method of processing seismic data acquired consequent to actuation of a seismic source is described. The method comprises taking the result of the following process into account when processing the seismic data where the process comprises estimating the effect of uncertainty in the position and/or orientation of the seismic source relative to the measuring receiver on processing the seismic data by estimating a source wavefield from data acquired by a near-field measuring receiver and from a first parameter set including at least one parameter indicative of the position and/or orientation of the seismic source relative to the measuring receiver, varying the value of at least one parameter of the first parameter set, estimating the source wavefield from the data acquired by the measuring receiver and from the varied first parameter set and obtaining information about the uncertainty in the estimate of the source wavefield.

First claim

The invention claimed is:

1. A method of identifying geological structure within the Earth including processing seismic data acquired consequent to actuation of a seismic source array, the method comprising the steps of:
(a) determining, by a computer processor, the source wavefield of the seismic source array and the uncertainty in the source wavefield by:
(i) estimating a source wavefield from measurements acquired by at least one near-field measuring receiver and from a first parameter set including at least one parameter indicative of the position or orientation of the seismic source array relative to the at least one measuring receiver;
(ii) varying the value of at least one parameter of the first parameter set;
(iii) estimating the source wavefield from the measurements acquired by the at least one measuring receiver and from the varied first parameter set; and
(iv) obtaining information about the uncertainty in the estimate of the source wavefield from the results of step (i) and (iii); and

(b) using the determined source wavefield of the seismic source array and the uncertainty in the source wavefield to process the seismic data to obtain information about at least one parameter of the earth's interior, wherein processing the seismic data includes selecting, for processing, a subset of the seismic data in which the expected uncertainty is low by either:
determining a frequency range in which the effect of uncertainty is low and selecting seismic data within the frequency range for processing; or
determining a range of take-off angles in which the effect of uncertainty is low and selecting seismic data within the range of take-off angles for processing.

2. A method as claimed in claim 1 and comprising the further steps of:
(c) (i) estimating the source wavefield from measurements acquired by the at least one near-field measuring receiver and from a second parameter set different from the first parameter set and including at least one parameter indicative of the position or orientation of the seismic source array relative to the at least one measuring receiver;
(ii) varying the value of at least one parameter of the second parameter set;
(iii) estimating the source wavefield from the measurements acquired by the at least one measuring receiver and from the varied second parameter set; and
(iv) obtaining further information about the uncertainty in the estimate of the source wavefield from the results of step (i) and (iii).

3. A method as claimed in claim 1 and comprising applying a constraint when varying the at least one parameter in step (ii).

4. A method as claimed in claim 1 wherein the at least one parameter comprises the position or depth of the seismic source.

5. A method as claimed in claim 1 wherein the at least one parameter comprises the position or depth of the measuring receiver.

6. A method as claimed in claim 1 wherein the at least one parameter comprises the tilt of two or more seismic sources of the source array.

7. A method as claimed in claim 1 wherein the at least one parameter comprises the skew of two or more seismic sources of the source array.

8. A method as claimed in claim 1 wherein the seismic data comprises marine seismic data.

9. A method as claimed in claim 8 wherein one of the first and second parameter sets comprises a parameter indicative of the state of the sea surface.

10. A method as claimed in claim 9 wherein one of the first and second parameter sets comprises the mean wave height.

11. A method as claimed in claim 1 wherein the data acquired by the measuring receiver comprises near-field data.

12. A method as claimed in claim 1 wherein the data acquired by the measuring receiver comprises near-field pressure data.

13. A method as claimed in claim 1 and comprising the step of acquiring the seismic data.

14. A method as claimed in claim 1 and comprising the step of acquiring the data at the measuring receiver.

Assignees

• Kostov Clement
• Hopperstad Jon-Fredrik
• Kitchenside Philip
• Robertsson Johan Olof Anders
• Schalkwijk Karin
• Westerngeco Llc

Inventors

• Kostov Clement
• Hopperstad Jon-Fredrik
• Kitchenside Philip
• Robertsson Johan Olof Anders
• Schalkwijk Karin

Classifications

• G01V1/364

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

• G01V2210/644

  Connectivity, e.g. for fluid movement · CPC title

• G01V1/28 Primary

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

• G01V99/005

  Physics · mapped topic

• G01V2210/66

  Subsurface modeling · CPC title