SEISMIC ACQUISITION SYSTEM AND TECHNIQUE

• US 20100195439A1
• Filed: 02/05/2009
• Published: 08/05/2010
• Est. Priority Date: 02/05/2009
• Status: Active Grant

• Current Assignee: WesternGeco LLC
• Original Assignee: WesternGeco LLC
• Inventors: Muyzert, Everhard
• Granted Patent: US 9,304,216 B2
• Time in Patent Office: Days
• US Class Current: 367/56
• CPC Class Codes: G01V 1/003 Seismic data acquisition in general, e.g. survey design G01V1/3808, G01V1/42 take precedence
• CPC Class Codes: G01V 1/18 Receiving elements, e.g. seismometer, geophone or torque detectors, for localised single point measurements
• CPC Class Codes: G01V 1/20 Arrangements of receiving elements, e.g. geophone pattern
• CPC Class Codes: G01V 1/301 for determining seismic cross-sections or geostructures
• CPC Class Codes: G01V 1/34 Displaying seismic recordings or visualisation of seismic data or attributes
• 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 2210/57 Trace interpolation or extrapolation, e.g. for virtual receiver; Anti-aliasing for missing receivers

Abstract

An apparatus includes an array of seismic sensor units that are adapted to acquire measurements in connection with a land surface-based seismic survey. Each seismic sensor unit includes a particle motion sensor and a rotation sensor.

Claims

1. An apparatus comprising:

an array of seismic sensor units adapted to acquire measurements in connection with a land surface-based seismic survey, each unit comprising a particle motion sensor and a rotation sensor.

2. The apparatus of claim 1, wherein the particle motion sensor comprises a geophone or an accelerometer.

3. The apparatus of claim 1, wherein the rotation sensor is adapted to provide a signal indicative of a rate of horizontal rotation.

4. The apparatus of claim 1, wherein each sensor unit further comprises an additional rotation sensor, and each rotation sensor of the sensor unit is oriented along a different orthogonal horizontal axis

5. The apparatus of claim 1, wherein the sensor units are spaced apart pursuant to a spacing distance of at least approximately three quarters to one wavelength of a slowest velocity of interest.

6. The apparatus of claim 5, wherein the slowest velocity of interest comprises a velocity associated with a ground roll.

7. The apparatus of claim 1, wherein the array of seismic sensor units is adapted to measure a one-dimensional survey geometry.

8. The apparatus of claim 1, wherein the array of seismic sensor units is adapted to measure a two-dimensional survey geometry.

9. The apparatus of claim 1, wherein the array of seismic units further comprises:

additional seismic units, each additional sensor unit comprising a particle motion sensor and not including any rotation sensors.

10. The apparatus of claim 9, wherein the seismic sensor units comprising particle motion sensors and rotation sensors are distributed in the vicinity of an obstruction and the additional seismic sensor units are distributed in a region away from the obstruction.

11. The apparatus of claim 1, further comprising:

packages, each package being associated with one of the seismic sensor units and containing the particle motion and rotation sensor of the unit.

12. The apparatus of claim 1, wherein the array of sensor units is located on a land surface or located in a borehole.

13. The apparatus of claim 1, wherein at least one of the seismic sensor units comprises:

a housing having a feature to enhance seismic coupling of the particle motion sensor and the rotation sensor.

14. The apparatus of claim 13, wherein the housing comprises a curved base plate.

15. The apparatus of claim 13, wherein the housing comprises at least three pins adapted to extend into the earth'"'"'s surface.

25. The system of claim 21, wherein the processor uses the particle motion and rotation rate data to separate compression and shear wavefields.

16. A method comprising:

receiving particle motion data and rotation rate data; and

processing the particle motion and rotation rate data to construct a subsurface image.

17. The method of claim 16, wherein the processing comprises:

attenuating at least one of a ground roll and an airwave.

18. The method of claim 16, wherein the attenuating comprises interpolating the wavefield at positions other than positions at which the particle motion and rotation rate data were acquired.

19. The method of claim 16, wherein the attenuating comprises applying an anti-aliasing filter.

20. The method of claim 16, wherein the processing comprises separating compression and shear wavefields.

21. A system comprising:

an interface to receive particle motion data and rotation rate data; and

a processor to process the particle motion and the rotation rate data to determine a subsurface image.

22. The system of claim 21, wherein the processor attenuates at least one of a ground roll and an airwave.

23. The system of claim 22, wherein the processor interpolates the wavefield at positions other than positions at which the particle motion and rotation rate data where sampled.

24. The system of claim 22, wherein the processor applies an anti-aliasing filter.