Magnetometer as an orientation sensor

• US 9,910,063 B2
• Filed: 02/09/2016
• Issued: 03/06/2018
• Est. Priority Date: 04/21/2015
• Status: Active Grant

• Current Assignee: PGS Geophysical As (PGS ASA)
• Original Assignee: PGS Geophysical As (PGS ASA)
• Inventors: Sdow, Gustav Gran Mattias, Hegna, Stian
• Primary Examiner(s): Bennett, G. Bradley
• Application Number:
  US15/019,831
• Publication Number:
  US 20160313366A1
• Time in Patent Office: 756 Days
• Field of Search: 33303, 33355 R
• CPC Class Codes: B63B 21/66 Equipment specially adapted for towing underwater objects or vessels, e.g. fairings for tow-cables paravanes for dragging fishing nets A01K73/02; salvaging underwater vessels or objects B63C7/00; towed underwater vessels B63G8/42
• CPC Class Codes: G01C 21/1654 with electromagnetic compass
• CPC Class Codes: G01C 21/185 for gravity
• CPC Class Codes: G01C 21/188 for accumulated errors, e.g. by coupling inertial systems with absolute positioning systems
• CPC Class Codes: G01C 9/02 Details
• CPC Class Codes: G01P 15/02 by making use of inertia forces using solid seismic massesG01P15/14 takes precedence
• CPC Class Codes: G01P 21/00 Testing or calibrating of apparatus or devices covered by the preceding groups
• CPC Class Codes: G01V 1/184 Multi-component geophones
• CPC Class Codes: G01V 1/189 Combinations of different types of receiving elements
• CPC Class Codes: G01V 1/201 Constructional details of seismic cables, e.g. streamers integrated optoseismic systems G01V1/226; line connectors in general H01R, transducer mountings in general G10K11/004
• CPC Class Codes: G01V 1/3808 Seismic data acquisition, e.g. survey design
• CPC Class Codes: G01V 11/00 Prospecting or detecting by methods combining techniques covered by two or more of main groups G01V1/00 - G01V9/00
• CPC Class Codes: G01V 3/15 specially adapted for use during transport, e.g. by a person, vehicle or boat
• CPC Class Codes: G01V 3/18 specially adapted for well-logging

Abstract

Included are methods and systems for marine geophysical surveying. A system includes a streamer; a sensor package coupled to the streamer, wherein the sensor package comprises a primary orientation sensor and a complimentary orientation sensor, wherein the complimentary orientation sensor comprises a magnetometer, wherein the primary orientation sensor and the complimentary orientation sensor are capable of collecting data indicative of the orientation of the streamer; and geophysical sensors distributed on the streamer.

Claims

1. A system comprising:

a streamer;

a sensor package coupled to the streamer, wherein the sensor package comprises a primary orientation sensor and a complimentary orientation sensor, wherein the complimentary orientation sensor comprises a magnetometer, wherein the primary orientation sensor and the complimentary orientation sensor are capable of collecting data indicative of the orientation of the streamer, wherein the data from the complimentary orientation sensor is used to determine roll angle of the streamer; and

geophysical sensors distributed on the streamer.

2. The system of claim 1 wherein the primary orientation sensor and the complimentary orientation sensor are co-located.

3. The system of claim 1 wherein the primary orientation sensor and the complimentary orientation sensor are integrated.

4. The system of claim 1 wherein the primary orientation sensor comprises an accelerometer.

5. The system of claim 1 wherein the primary orientation sensor comprises a micro-electrical mechanical systems accelerometer.

6. The system of claim 1 wherein the complimentary orientation sensor comprises a permalloy.

7. The system of claim 1 wherein the primary orientation sensor is DC-coupled to the Earth'"'"'s gravitational field and wherein the complimentary orientation sensor is DC-coupled to the Earth'"'"'s magnetic field.

8. The system of claim 1 wherein each geophysical sensor is selected from the group consisting of a seismic sensor, a geophone, a hydrophone, an accelerometer, an electromagnetic field sensor, and combinations thereof.

9. The system of claim 8 wherein at least one of the geophysical sensors comprises a non-gimbaled AC-coupled motion sensor.

10. The system of claim 1 wherein the streamer comprises a plurality of sensor packages, wherein the sensor packages have a spacing on the streamer of about 2 meters to about 50 meters, and wherein each sensor package in the plurality of sensor packages comprises a primary orientation sensor.

11. A system comprising:

a streamer;

a plurality of sensor packages coupled to the streamer, wherein each of the sensor packages comprise a primary orientation sensor and a complimentary orientation sensor, wherein the complimentary orientation sensor comprises a magnetometer, wherein the primary orientation sensor comprises a DC-coupled accelerometer;

wherein the primary orientation sensor and the complimentary orientation sensor are capable of collecting data indicative of the orientation of the streamer wherein the data from the complimentary orientation sensor is used to determine roll angle of the streamer; and

geophysical sensors distributed on the streamer, wherein each of the geophysical sensors is selected from the group consisting of a seismic sensor, a geophone, a hydrophone, an accelerometer, an electromagnetic field sensor, and combinations thereof.

12. The system of claim 11 wherein the primary orientation sensor and the complimentary orientation sensor are co-located.

13. The system of claim 11 wherein at least one of the geophysical sensors comprises a non-gimbaled AC-coupled motion sensor.

14. The system of claim 11 wherein the sensor packages have a spacing on the streamer of about 2 meters to about 50 meters.

15. A method comprising:

towing a streamer behind a survey vessel in a body of water, wherein the streamer comprises a sensor package comprising a primary orientation sensor and a complimentary orientation sensor, wherein the complimentary orientation sensor is a magnetometer;

turning the survey vessel;

receiving data from the primary orientation sensor and the complimentary orientation sensor indicative of the orientation of the streamer during the turn of the survey vessel, the data from the complimentary orientation sensor being used to determine roll angle; and

using the data from the complimentary orientation sensor to mitigate noise present in the data from the primary orientation sensor.

16. The method of claim 15 further comprising:

detecting energy using one or more geophysical sensors disposed on the streamer; and

producing a geophysical data product from the detected energy indicative of certain properties of a subsurface formation below the body of water.

17. The method of claim 15 further comprising importing the geophysical data product into the United States.

18. The method of claim 15, measuring acceleration with the primary orientation sensor.

19. The method of claim 15, further comprising co-locating the primary orientation sensor and the complementary orientation sensor on a circuit board.

20. The method of claim 15, wherein the step of using the data from the complimentary orientation sensor to mitigate noise present in the data from the primary orientation sensor comprising using the data from the complimentary orientation sensor to determine roll angle of the streamer while the survey vessel is turning to mitigate effects of overlaid linear acceleration on the data from the primary orientation sensor.