USING A DISTRIBUTED OPTICAL ACOUSTIC SENSOR TO POSITION AN OBJECT

• US 20120020184A1
• Filed: 07/26/2010
• Published: 01/26/2012
• Est. Priority Date: 07/26/2010
• Status: Abandoned Application

• Current Assignee: WesternGeco LLC (Schlumberger NV)
• Original Assignee: WesternGeco LLC (Schlumberger NV)
• Inventors: Wilson, Colin, Robertsson, Johan O. A., Kragh, Julian Edward (Ed), Muyzert, Everhard, Welker, Kenneth E., Miller, Douglas
• Application Number:
  US12/843,416
• Publication Number:
  US 20120020184A1
• Time in Patent Office: Days
• US Class Current: 367/16
• CPC Class Codes: G01H 9/004 using fibre optic sensors light guides per se G02B6/00, acousto-optical devices specially adapted for gating or modulating in optical wave guides G02F1/125
• 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 1/3835 measuring position, e.g. by GPS or acoustically

Abstract

A distributed optical acoustic sensor is provided along a structure in a body of water. The distributed optical acoustic sensor is used to detect acoustic waves generated by at least one acoustic source for positioning of at least one object in relation to the structure.

Claims

1. A method comprising:

providing a distributed optical acoustic sensor along a structure in a body of water; and

using the distributed optical acoustic sensor to detect acoustic waves generated by at least one acoustic source for positioning of at least one object in relation to the structure.

2. The method of claim 1, wherein the at least one object includes one or more portions of the structure, and wherein using the distributed optical acoustic sensor comprises receiving backscattered optical signals from the distributed optical acoustic sensor to determine one or more positions of the one or more portions of the structure.

3. The method of claim 2, wherein the structure is a marine streamer having sensors to perform subterranean surveying, and wherein receiving the backscattered optical signals comprises receiving the backscattered optical signals for positioning the streamer.

4. The method of claim 1, wherein the at least one acoustic source is mounted on the structure.

5. The method of claim 1, wherein the at least one object includes an external object separate from the structure, and wherein using the optical acoustic sensor comprises using the distributed optical acoustic sensor to detect proximity of the external object to the structure.

6. The method of claim 5, wherein the external object is one of a marine vessel and a living being.

7. The method of claim 5, wherein positioning the external object is performed as part of passive acoustic monitoring.

8. The method of claim 1, wherein the at least one acoustic source includes acoustic pingers along the structure, the method further comprises activating the acoustic pingers to generate the acoustic waves.

9. The method of claim 1, wherein providing the distributed optical acoustic sensor comprises providing the distributed optical acoustic sensor that has an optical fiber, wherein the optical fiber is coupled to an optical source that emits optical signals into the optical fiber, and the optical fiber is coupled to a receiver to receive backscattered optical signals responsive to the optical signals emitted by the optical source.

10. The method of claim 9, further comprising:

analyzing the backscattered optical signals to perform positioning of the at least one object, wherein the backscattered optical signals are affected by strain on one or more portions of the optical fiber caused by the acoustic waves.

11. A system comprising:

at least one acoustic source to generate acoustic waves;

an elongate structure for deployment in a body of water; and

a distributed optical acoustic sensor arranged along the elongate structure, the distributed optical acoustic sensor configured to produce optical backscattered signals responsive to the acoustic waves for positioning at least one object in relation to the structure.

12. The system of claim 11, wherein the distributed optical acoustic sensor comprises at least one optical fiber to receive optical signals launched from an optical source and to return the optical backscattered signals in response to the launched optical signals.

13. The system of claim 12, further comprising:

a receiver to receive the optical backscattered signals; and

a signal processing module configured to analyze data representing the optical backscattered signals to perform positioning of the at least one object.

14. The system of claim 11, wherein the at least one source includes one or more acoustic pingers along the structure.

15. The system of claim 11, wherein the at least one source is positioned on a component separate from the structure, wherein the component includes one of a marine vessel, a platform, a buoy, and an aircraft.

16. The system of claim 11, wherein the at least one object is an external object separate from the structure, and wherein the at least one source is part of the external object.

17. The system of claim 11, wherein the structure has survey sensors configured to receive signals reflected from or affected by a subterranean structure.

18. The system of claim 17, wherein the survey sensors comprise seismic sensors or electromagnetic sensors.

19. An article comprising at least one computer-readable storage medium storing instructions that upon execution cause a processor to:

receive data representative of optical backscattered signals from a distributed optical acoustic sensor, wherein the distributed optical acoustic sensor is arranged along a structure deployed in a body of water, and wherein the optical backscattered signals are affected by acoustic waves impinging on the distributed optical acoustic sensor; and

analyze the data to determine one or more positions of at least one object of interest in relation to the structure.

20. The article of claim 19, wherein the at least one object of interest includes portions of the structure or an external object that may collide with the structure.