Dual-wavefield multiple attenuation
AssigneeWesternGeco L.L.C.
InventorWilliam Henry Dragoset, Jr.
Life of this patent
Estimating the term…
Abstract
Method for attenuating surface multiple reflections in dual-wavefield seismic data. In one implementation, the method may include: (a) performing wavefield separation on dual-wavefield seismic data to separate events in the seismic data into data sets according to ghost characteristics; (b) applying a multidimensional Surface-Related Multiple Elimination (SRME) to two or more of the data sets to yield an SRME result in a manner that retains surface reflection information affecting surface multiple reflections; and (c) repeating step (b) one or more times.
Claims18
A method for attenuating surface multiple reflections in dual-wavefield seismic data, comprising:
- (a) performing wavefield separation on dual-wavefield seismic data to separate events in the seismic data into data sets according to ghost characteristics, wherein the dual-wavefield seismic data have been acquired by two or more sensors;
- (b) applying a multidimensional Surface-Related Multiple Elimination (SRME) to two or more of the data sets to yield an SRME result in a manner that retains surface reflection information affecting surface multiple reflections;
- and
- (c) repeating step (b) one or more times using the SRME result from the previous step (b) as one of the data sets for the multidimensional SRME.
A computer-readable non-transitory medium having stored thereon computer-executable instructions which, when executed by a computer, cause the computer to:
- (a) perform wavefield separation on dual-wavefield seismic data to separate events in the seismic data into data sets according to ghost characteristics, wherein the dual-wavefield seismic data have been acquired by two or more sensors;
- (b) perform multi-dimensional convolutions using two or more of the data sets to predict multiples;
- (c) adaptively subtract the predicted multiples from one of the data sets to yield an SRME result;
- and
- (d) repeat steps (b)-(c) one or more times using the SRME result from the previous step (c) when performing the multi-dimensional convolutions.
A computer system, comprising:
- a processor;
- and
- a memory comprising program instructions executable by the processor to:
- (a) perform source-side wavefield separation on dual-wavefield seismic data to divide the seismic data into a source-side upgoing data set and a source-side downgoing data set, wherein the dual-wavefield seismic data have been acquired by two or more sensors;
- (b) discard the source-side upgoing data set;
- (c) perform receiver-side wavefield separation on the source-side downgoing data set to subdivide the source-side downgoing data set into a source-side downgoing and receiver-side upcoming data set and a source-side downgoing and receiver-side downcoming data set;
- (d) perform multi-dimensional convolutions using the source-side downgoing and receiver-side upcoming data set and the source-side downgoing and receiver-side downcoming data set to predict multiples;
- (e) adaptively subtract the predicted multiples from the source-side downgoing and receiver-side upcoming data set to yield an SRME result;
- and
- (f) repeat steps (d)-(e) one or more times using the SRME result from the previous step (e) in place of the source-side downgoing and receiver-side upcoming data set when performing the multi-dimensional convolutions of step (d).
Dependencies are inferred from the claim text.