Steering for coverage in seismic surveys
AssigneeCgg Services SAS
InventorsTimothee Moulinier, Thomas Mensch
Life of this patent
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Abstract
A method for steering a marine seismic acquisition system by determining a steering point associated with towed seismic equipment is described. Coverage boundaries for a current line in a seismic survey and for an already acquired adjacent line in the seismic survey are computed. Cross-line distances between the coverage boundary for the current line and the coverage boundary for the adjacent line are computed based on a set of specifications for the seismic survey. A steering point associated with towed seismic equipment is determined based on the computed cross-line distances. A least one steering command for a steering element in the marine seismic acquisition system is generated based on the determined steering point.
Claims10
A method for configuring a marine seismic acquisition system, the method comprising:
- computing coverage boundaries for a current line in a seismic survey and for an already acquired adjacent line in the seismic survey;
- computing cross-line distances between the coverage boundary for the current line and the coverage boundary for the adjacent line based on a set of specifications for the seismic survey;
- determining a steering point associated with towed seismic equipment based on the computed cross-line distances;
- and
- generating at least one steering command for a steering element in the marine seismic acquisition system based on the determined steering point,
- wherein the method further comprises:
- computing a coverage at a common midpoint (CMP) of each offset class for the seismic survey;
- determining a cross-line distance for each CMP offset class needed to meet coverage criteria for the seismic survey;
- using the determined cross-line distances, select a CMP at a fold limit associated with the seismic survey from each offset class;
- and
- selecting, as the steering point, the CMP associated with one of the offset classes which has the largest cross-line distance.
A system for collecting seismic data comprising:
- at least one vessel that tows seismic equipment capable of generating and/or receiving seismic waves;
- and
- a processor, associated with a navigation system, which is configured to:
- compute coverage boundaries for a current line in a seismic survey and for an already acquired adjacent line in the seismic survey;
- compute cross-line distances between the coverage boundary for the current line and the coverage boundary for the adjacent line based on a set of specifications for the seismic survey;
- determine a steering point associated with towed seismic equipment based on the computed cross-line distances;
- and
- generate at least one steering command for a steering element in the system based on the determined steering point,
- wherein the processor is further configured to:
- compute a coverage at a common midpoint (CMP) of each offset class for the seismic survey;
- determine a cross-line distance for each CMP offset class needed to meet coverage criteria for the seismic survey;
- use the determined cross-line distances to select a CMP at a fold limit associated with the seismic survey from each offset class;
- and
- select, as the steering point, the CMP associated with one of the offset classes which has the largest cross-line distance.
Dependencies are inferred from the claim text.