Noise attenuation in passive seismic data

• US 8,838,392 B2
• Filed: 11/16/2010
• Issued: 09/16/2014
• Est. Priority Date: 10/05/2009
• Status: Active Grant

• Current Assignee: WesternGeco LLC
• Original Assignee: WesternGeco LLC
• Inventors: Halliday, David Fraser, Muyzert, Everhard, Edme, Pascal
• Primary Examiner(s): Teixeira Moffat, Jonathan C
• Assistant Examiner(s): BETSCH, REGIS J
• Application Number:
  US12/947,144
• Publication Number:
  US 20110082646A1
• Time in Patent Office: 1,400 Days
• Field of Search: 702/17, 367/40
• US Class Current: 702/17
• CPC Class Codes: G01V 1/189 Combinations of different types of receiving elements
• CPC Class Codes: G01V 1/36 Effecting static or dynamic corrections on records, e.g. correcting spread; Correlating seismic signals; Eliminating effects of unwanted energy
• CPC Class Codes: G01V 1/366 by correlation of seismic signals
• CPC Class Codes: G01V 2210/123 Passive source, e.g. microseismics
• CPC Class Codes: G01V 2210/144 with functionally associated receivers, e.g. hydrophone and geophone pairs
• CPC Class Codes: G01V 2210/169 Sparse arrays
• CPC Class Codes: G01V 2210/32 Noise reduction
• CPC Class Codes: G01V 2210/3246 Coherent noise, e.g. spatially coherent or predictable

Abstract

Passive seismic data is collected from measurements of seismic sensors in respective sensor assemblies, where the passive seismic data is based on measurements collected during periods when no active seismic source was activated. Attenuation of surface noise in the passive seismic data is performed using data from divergence sensors in at least some of the sensor assemblies. The passive seismic data with surface noise attenuated is output to allow for performing an operation related to a subterranean structure using the passive seismic data with the surface noise attenuated.

Claims

1. A method comprises:

receiving, by a system having a processor, passive seismic data collected from measurements of seismic sensors in respective sensor assemblies, wherein the passive seismic data is based on multi-component measurements along two or more directions collected during periods when no active seismic source was activated;

performing, by the system, attenuation of ground-roll noise in the passive seismic data using data from divergence sensors in at least some of the sensor assemblies, the data from the divergence sensors comprising measurements insensitive to a direction of wave propagation, wherein each of the divergence sensors includes a container containing a material and a pressure sensor immersed in the material, the divergence sensor and the seismic sensor of each of the at least some sensor assemblies are collocated, and the divergence sensors are buried below a ground surface and a portion of each of the at least some sensor assemblies including the respective divergence sensor is in contact with an earth medium underneath the ground surface; and

outputting, by the system, the passive seismic data with the ground-roll noise attenuated to allow for performing an operation related to a subterranean structure using the passive seismic data with the ground-roll noise attenuated.

2. The method of claim 1, further comprising:

using the passive seismic data with the ground-roll noise attenuated to develop a subsurface image of the subterranean structure.

3. The method of claim 1, further comprising:

using the passive seismic data with the ground-roll noise attenuated to develop a model of the subterranean structure.

4. The method of claim 1, further comprising:

using the passive seismic data with the ground-roll noise attenuated to perform passive seismic interferometry.

5. The method of claim 4, wherein performing the passive seismic interferometry comprises:

classifying the passive seismic data as seismic data below a predefined frequency threshold.

6. The method of claim 5, wherein performing the passive seismic interferometry comprises calculating a set of Green'"'"'s functions based on the passive seismic data, the method further comprising using the set of Green'"'"'s functions to produce an image of the subterranean structure.

7. The method of claim 1, further comprising:

using the passive seismic data with the ground-roll noise attenuated to perform passive data reservoir monitoring to monitor a reservoir in a subterranean structure.

8. The method of claim 1, further comprising:

receiving the data from the divergence sensors.

9. The method of claim 1, wherein the material includes liquid.

10. An article comprising at least one non-transitory machine-readable storage medium storing instructions that upon execution cause a system having a processor to:

receive seismic data collected from measurements of seismic sensors in respective sensor assemblies;

identify passive seismic data in the received seismic data, wherein the passive seismic data is based on multi-component measurements along two or more directions collected by the seismic sensors during periods when no active seismic source was activated;

perform attenuation of ground-roll noise in the passive seismic data using data from divergence sensors in at least some of the sensor assemblies, the data from the divergence sensors comprising measurements insensitive to a direction of wave propagation, wherein each of the divergence sensors includes a container containing a material and a pressure sensor immersed in the material, the divergence sensor and the seismic sensor of each of the at least some sensor assemblies are collocated, and the divergence sensors are buried below a ground surface and a portion of each of the at least some sensor assemblies including the respective divergence sensor is in contact with an earth medium underneath the ground surface; and

perform an operation related to a subterranean structure using the passive seismic data with the ground-roll noise attenuated.

11. The article of claim 10, wherein the operation includes generating an image of the subterranean structure.

12. The article of claim 10, wherein the operation includes generating a model of the subterranean structure.

13. The article of claim 12, wherein the model is a velocity model.

14. The article of claim 10, wherein the operation includes reservoir monitoring of a reservoir in the subterranean structure.

15. A system comprising:

sensor assemblies, wherein at least some of the sensor assemblies each includes a seismic sensor and a divergence sensor; and

a controller to;

receive passive seismic data collected from measurements of the seismic sensors, wherein the passive seismic data is based on multi-component measurements along two or more directions collected during periods when no active seismic source was activated;

perform attenuation of ground-roll noise in the passive seismic data using data from the divergence sensors, the data from the divergence sensors comprising measurements insensitive to a direction of wave propagation, wherein each of the divergence sensors includes a container containing a material and a pressure sensor immersed in the material, the divergence sensor and the seismic sensor of each of the at least some sensor assemblies are collocated, and the divergence sensors are buried below a ground surface and a portion of each of the at least some sensor assemblies including the respective divergence sensor is in contact with an earth medium underneath the ground surface; and

output the passive seismic data with the ground-roll noise attenuated to allow for performing an operation related to a subterranean structure using the passive seismic data with the ground-roll noise attenuated.

16. The system of claim 15, wherein the material includes liquid.

17. The system of claim 15, wherein the operation is selected from the group consisting of:

generating an image of the subterranean structure;

generating a model of the subterranean structure;

performing passive seismic interferometry; and

performing reservoir monitoring.

18. The method of claim 15, wherein each of the at least some sensor assemblies includes a housing containing the corresponding seismic sensor and divergence sensor.