Marine seismic survey method and system
An inventive method provides for control of a seismic survey spread while conducting a seismic survey, the spread having a vessel, a plurality of spread control elements, a plurality of navigation nodes, and a plurality of sources and receivers. The method includes the step of collecting input data, including navigation data for the navigation nodes, operating states from sensors associated with the spread control elements, environmental data for the survey, and survey design data. The positions of the sources and receivers are estimated using the navigation data, the operating states, and the environmental data. Optimum tracks for the sources and receivers are determined using the position estimates and a portion of the input data that includes at least the survey design data. Drive commands are calculated for at least two of the spread control elements using the determined optimum tracks. The inventive method is complemented by an inventive system.
1. A method comprising:
towing a plurality of seismic survey sources and receivers generally behind a vessel having one or more spread control elements;
estimating one or more positions of the sources based on data received from one or more reference points on a seismic survey spread with respect to the earth; and
activating a selected portion of the sources when the selected portion is within a vicinity of desired cross line positions of a desired track.
2. The method of claim 1 , wherein the number of the selected portion of the sources is less than the total number of sources.
3. The method of claim 1 , wherein the receivers are towed in a plurality of linear streamers; and wherein the selected portion of the sources forms at least one linear source array parallel to the streamers.
4. The method of claim 1 , further comprising:
collecting input data from the seismic survey spread having a plurality of spread control elements, a plurality of navigation nodes, and a plurality of sources and receivers;
estimating positions of the sources and receivers using one or more navigation data, one or more operating states, and one or more environmental data;
determining optimum tracks for the sources and receivers using the estimated positions and a portion of the input data that includes at least the survey design data; and
calculating drive commands for at least one of the spread control elements using the determined optimum tracks.
5. The method of claim 1 , wherein the at least one of the spread control elements is a spread control element for a vessel or a spread control element for a receiver.
6. A seismic survey apparatus, comprising:
a vessel;
a plurality of seismic survey sources and receivers generally towed behind the vessel and having one or more spread control elements;
a controller coupled to the seismic survey sources, receivers and the spread control elements, wherein the controller is configured to:
estimate one or more positions of the sources based on data received from one or more reference points on the seismic survey apparatus with respect to the earth; and
selectively activate a portion of the sources that is closest to a vicinity of desired cross line positions of a desired track.
7. The method of claim 1 , wherein the reference points comprise at least two reference points located on opposite corners of the seismic survey spread.
8. The method of claim 1 , wherein the reference points comprise at least two reference points, and wherein each reference point is located at a corner of the seismic survey spread.
9. The method of claim 1 , wherein estimating the positions of the sources comprises estimating the positions of the acoustic positioning receivers on the sources.
10. The method of claim 1 , further comprising steering the selected portion of the sources within a cross line corridor to the vicinity near the desired cross line positions.
11. The method of claim 1 , further comprising estimating the positions of the sources based on data received from one or more acoustic positioning devices.