Method to determine the deviation of seismic equipment from a planned curved path
View Patent ↗A group of techniques can be used to determine if components of a seismic spread have deviated from a planned path during a coil or other curved and substantially circular acquisition pattern. In one aspect, and in general, the presently disclosed techniques include a computer-readable program storage medium for determining the deviation of spread array element from a planned curved path during a towed-array marine seismic survey. The method comprises: determining a nominal position of the spread array element at a given point in the planned curved path; determining the actual position of the spread array element; and performing an error analysis predicated on the nominal and actual positions.
1. A computer-implemented method for determining a deviation of a spread array element from a planned curved path during a towed-array marine seismic survey, comprising:
towing a seismic survey spread using a survey vessel wherein the seismic survey spread includes the spread array element associated therewith:
determining a nominal position of the spread array element at a given point in the planned curved path, wherein the planned curved path is selected from at least one of a coil path, a circular path, an ovoid path, an elliptical path, and a figure-eight path;
determining an actual position of the spread array element; and performing an error analysis based on the nominal position and the actual position; and
correcting an error in the actual position of the spread array element based on the error analysis.
2. The computer-implemented method of claim 1 , wherein determining the nominal position of the spread array element comprises determining the nominal position from an equipment nominal offset and a shot number.
3. The computer-implemented method of claim 1 , wherein determining the nominal position of the spread array element comprises determining a distance along and a distance across.
4. The computer-implemented method of claim 1 , wherein determining the actual position of the spread array element comprises determining the actual position using acoustic ranging or a Global Positioning System (GPS).
5. The computer-implemented method of claim 1 , wherein performing the error analysis comprises performing the error analysis during the marine seismic survey to correct a position error for the spread array element.
6. The computer-implemented method of claim 1 , wherein performing the error analysis comprises performing the error analysis after the marine seismic survey for quality control.
7. The computer-implemented method of claim 1 , wherein performing the error analysis comprises performing at least one of: determining a difference between a desired position and the actual position of the spread array element; issuing one or more steering commands to one or more steering devices based on the difference; producing a plot based on the difference between a desired position and the actual position; computing one or more statistics establishing whether one or more survey specifications are being met; and displaying the plot to the user.
8. A programmed computing apparatus located on board a survey vessel comprising:
a processor located on board the survey vessel and one or more communication devices located at a seismic survey spread, the one or more communication devices being in communication with the processor:
a storage on board the survey vessel accessible by the processor;
a software component residing on the storage that, when executed by the processor, will perform a method for determining a deviation of a spread array element from a planned curved path during a towed-array marine seismic survey, wherein the planned curved path is selected from at least one of a coil path, a circular path, an ovoid path, an elliptical path, and a figure-eight path, the method comprising:
determining a nominal position of the spread array element at a given point in the planned curved path;
determining an actual position of the spread array element; and performing an error analysis based on the nominal position and the actual position; and
correcting an error in the actual position of the spread array element based on the error analysis.
9. The programmed computing apparatus of claim 8 , wherein determining the nominal position of the spread array element comprises determining the nominal position from an equipment nominal offset and a shot number.
10. The programmed computing apparatus of claim 8 , wherein determining the nominal position of the spread array element comprises determining a distance along and a distance across.
11. The programmed computing apparatus of claim 8 , wherein determining the actual position of the spread array element comprises determining the actual position using acoustic ranging or a Global Positioning System (GPS).
12. The programmed computing apparatus of claim 8 , wherein performing the error analysis comprises performing the error analysis during the marine seismic survey to correct a position error for the spread array element.
13. The programmed computing apparatus of claim 8 , wherein performing the error analysis comprises performing the error analysis after the marine seismic survey for quality control.
14. The programmed computing apparatus of claim 8 , wherein performing the error analysis comprises performing at least one of:
determining a difference between a desired position and the actual position of the spread array element;
issuing one or more steering commands to one or more steering devices based on the difference;
producing a plot based on the difference between a desired position and the actual position;
computing one or more statistics establishing whether one or more survey specifications are being met; and
displaying the plot to the user.
15. A method, comprising:
towing a seismic survey spread using a survey vessel along a curved path selected from at least one of a coil path, a circular path, an ovoid path, an elliptical path, and a figure-eight path; and
positioning a spread array element of the seismic survey spread during the traversal, comprising:
determining a nominal position of the spread array element at a given point in the curved path;
determining an actual position of the spread array element; performing an error analysis based on the nominal position and the actual position; and
correcting an error in the actual position of the spread array element based on the error analysis.
16. The method of claim 15 , wherein determining the nominal position of the spread array element comprises determining the nominal position from an equipment nominal offset and a shot number.
17. The method of claim 15 , wherein determining the nominal position of the spread array element comprises determining a distance along and a distance across.
18. The method of claim 15 , wherein determining the actual position of the spread array element comprises determining the actual position using acoustic ranging or a Global Positioning System (GPS).
19. The method of claim 15 , wherein performing the error analysis comprises performing the error analysis during the seismic survey to correct a position error for the spread array element.
20. The method of claim 15 , wherein performing the error analysis comprises performing the error analysis after the seismic survey for quality control.
21. The method of claim 15 , wherein performing the error analysis comprises performing at least one of:
determining a difference between a desired position and the actual position of the spread array element;
issuing one or more steering commands to one or more steering devices based on the difference;
producing a plot based on the difference between a desired position and the actual position;
computing one or more statistics establishing whether one or more survey specifications are being met; and
displaying the plot to the user.