Methods for deblending of seismic shot gathers

Patent metadata

Field	Value
Publication number	US-9602781-B2
Application number	US-201214112502-A
Country	US
Kind code	B2
Filing date	Mar 21, 2012
Priority date	Apr 18, 2011
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

A system and methods to deblend seismic data from a plurality of sources and received by a plurality of sensors as shot gathers are disclosed. The deblending is performed by a Mutual Interdependence Analysis Method to separate contributions of different shots. Deblending is also performed by applying a measure of coherence in parallel data domains such as Common Shot Gather and Common Midpoint. Deblending is also achieved by using the hyperbolic nature of seismic data in the common midpoint domain. Deblended signals are estimated and are applied to create a seismic image. Also, Bergman iteration based migration is applied directly on the blended seismic shot gathers without first deblending as an alternative method. The methods are applied in seismic imaging for exploration of natural resources.

First claim

The invention claimed is:

1. A method for deblending seismic data, the method comprising:
acquiring, with a processor, blended seismic data in a plurality of recordings from a plurality of sensors, each sensor of the plurality of sensors generating a plurality of blended signals generated by a plurality of semi-simultaneously fired sources, wherein each source of the plurality of semi-simultaneously fired sources is fired more than once;
selecting, with the processor, a first source from the plurality of semi-simultaneously fired sources and a plurality of blended signals received by a first sensor;
arranging, with the processor, recordings of the plurality of blended signals received by the first sensor to align with a timing of the first source; and
applying, with the processor, Mutual Interdependence Analysis (MIA) to estimate from at least two aligned blended signals a deblended signal received at the first sensor and attributed to the first source.

2. The method of claim 1 , further comprising:
arranging recordings of a plurality of blended signals acquired by a second sensor to align with the timing of the first source.

3. The method of claim 2 , further comprising:
arranging recordings of the plurality of blended signals received by the first sensor to align with a timing of a second source.

4. The method of claim 1 , further comprising:
generating a seismic image based on the estimated deblended signal.

5. The method of claim 1 , wherein the method is applied in oil exploration.

6. The method of claim 1 , wherein the method is applied in gas exploration.

7. The method of claim 1 , wherein applying Mutual Interdependence Analysis comprises evaluating an expression:

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wherein ŝ n,m is estimated deblended data from source n at sensor m, X m is a collection of recordings at sensor m from all experiments, r n,m (e) is a vector that indicates which of the experiments contain an aligned target source e, n indicates a source, m indicates a sensor, α i is a weight of a single shot recording i in a recording of the currently analyzed sensor x m , and s i is a single shot recordings of shot locations i.

8. A method for deblending blended seismic data, the method comprising:
acquiring, with a processor, blended seismic data in a plurality of recordings from a plurality of sensors, each sensor of the plurality of sensors receiving a blended signal generated by at least a first semi-simultaneous source and a second semi-simultaneous source and the processor recording a plurality of datapoints, each datapoint of the plurality of datapoints being associated with a respective sensor of the plur

Assignees

• Claussen Heiko
• Chang Ti-Chiun
• Rosca Justinian
• Siemens Ag

Inventors

• Claussen Heiko
• Chang Ti-Chiun
• Rosca Justinian

Classifications

• G01V1/36

  Effecting static or dynamic corrections on records, e.g. correcting spread; Correlating seismic signals; Eliminating effects of unwanted energy · CPC title

• G01V1/003 Primary

  Seismic data acquisition in general, e.g. survey design (G01V1/3808, G01V1/42 take precedence) · CPC title

• H04N7/18 Primary

  Closed-circuit television [CCTV] systems, i.e. systems in which the video signal is not broadcast · CPC title