Method for optimizing acoustic source array performance

Patent metadata

Field	Value
Publication number	US-9500761-B2
Application number	US-201314047664-A
Country	US
Kind code	B2
Filing date	Oct 7, 2013
Priority date	Dec 17, 2008
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

A technique facilitates obtaining seismic data in a marine environment. An array of acoustic sources is deployed in a marine environment. The array can be utilized for creating acoustic pulses that facilitate the collection of data on subsea structures. The methodology enables optimization of acoustic source array performance to improve the collection of useful data during a seismic survey.

First claim

What is claimed is:

1. A method, comprising:
deploying an array of acoustic sources in a marine environment;
creating acoustic pulses with the acoustic sources to obtain data on subterranean formations; and
deliberately delaying triggering of the acoustic sources with respect to one another in a manner such that the power spectrum of the array is attenuated at frequencies outside of a desired seismic frequency band without substantially affecting output within the desired frequency band.

2. The method of claim 1 , wherein deliberately delaying comprises selecting time delays such that signal amplitudes outside a predetermined seismic band are attenuated while signal amplitudes within the predetermined band are substantially unaffected.

3. The method of claim 2 , wherein selecting time delays comprises confining the time delays to a window length that is greater than 1 millisecond.

4. The method of claim 2 , wherein selecting comprises selecting time delays that are randomly drawn from a chosen distribution.

5. A method, comprising:
operating an array of acoustic sources in a marine environment to obtain seismic data;
using the array of acoustic sources to deliver primary pressure pulses into the marine environment; and
deliberately delaying primary pressure pulses such that the power spectrum of the array is attenuated at frequencies outside of a desired seismic frequency band without substantially affecting output within the desired frequency band.

6. The method of claim 5 , wherein the delays are substantially uniformly distributed.

7. A method, comprising:
operating an array of acoustic sources in a marine environment to obtain seismic data;
using the array of acoustic sources to deliver pressure pulses into the marine environment; and
operating components of the array so that the firing of the components happens with a delay between each other over time, thereby reducing the maximum output of the array.

8. The method of claim 7 , wherein the firing of the components of the array is based on a predetermined pattern.

9. A method, comprising:
positioning a seismic source array of a seismic survey region, the seismic source array comprising components that each generate an output amplitude, the source array therefore together generating an output amplitude;
activating the seismic source array so that there is a delay between different components within the seismic source array thereby reducing the output amplitude of the seismic source array; and
recording seismic signals reflected from subterranean formations.

10. The method of claim 9 , wherein the outputs of the components in the seismic source array are controlled by a control system that is operatively couples to the seismic source array.

Assignees

• Westerngeco Llc
• Westerngeco Llc

Inventors

• Hopperstad Jon-Fredrik
• Laws Robert Montgomery
• Melboe Aslaug Strømmen

Classifications

• G01V1/00 Primary

  Seismology; Seismic or acoustic prospecting or detecting · CPC title

• G01V1/3808

  Seismic data acquisition, e.g. survey design · CPC title

• G01V1/08

  involving time-delay devices · CPC title

• G01V1/006 Primary

  generating single signals by using more than one generator, e.g. beam steering or focusing arrays (G01V1/13, G01V1/3861 take precedence) · CPC title

• G01V1/3861 Primary

  control of source arrays, e.g. for far field control · CPC title