A method and apparatus for operating a single source vessel along a survey path, the source vessel towing a source and a first plurality of streamers; operating a streamer vessel along the survey path, the streamer vessel towing a second plurality of streamers; actuating the source; acquiring near-offset data with a first plurality of receivers; and acquiring long-offset data with a second plurality of receivers. A system includes a source vessel coupled to: a source; and a near-offset survey spread; a streamer vessel coupled to a long-offset survey spread, wherein a streamer spacing density of the long-offset survey spread is no greater than a streamer spacing density of the near-offset survey spread; and a survey plan including navigation information for the source vessel and the streamer vessel, wherein the navigation information directs the source vessel and the streamer vessel along a common survey path while the source is actuated.

A seismic survey system is provided. The system can include a source array including a first sub-source array and a second sub-source array. The system can include a streamer coupled with the first sub-source array and a streamer coupled with the second sub-source array. The system can include a receiver array including a plurality of receivers. The system can include a lateral cable coupled with at least one of a first diverter or a second diverter and at least one of the first sub-source array or the second sub-source array. The system can include a positioning cable coupled with the first diverter and a positioning cable coupled with the second diverter. The system can include a power cable. The system can include a seismic data acquisition unit array including a plurality of seismic data acquisition units disposed on a seabed.

An autonomous sensor node for undersea seismic surveying is formed as a sphere with density similar to sea water in order to minimize effects of noise. The node is capable of measuring both seismic pressure waves and water-borne particle velocity in three dimensions. The node floats above the seafloor to greatly decrease the impact of shear wave noise contamination generated by seabed waves. The node is attached to an anchor resting on the seabed by a tether. The tether is configured to prevent transfer of any tensile forces caused by shear waves in the seabed stratum from the anchor to the node. The tether may have a varying density along its length to entirely attenuate any force transfer from the seafloor.

Embodiments herein include a fairing for a marine seismic array system that includes a foil having a leading edge and a trailing edge and defining a chord length and a span length, a first interior conduit oriented along the span length aft of the leading edge, and a second interior conduit oriented along the span length forward of the trailing edge. The conduits are separated by a distance. A first cable having a first length extends within the first conduit and a second cable having a second length extends within the second conduit, and the fairing can rotate about the first cable within the first conduit.

Geophysical survey methods. At least some of the example embodiments are methods of performing a marine geophysical survey including: towing a plurality of sensor streamers behind a tow vessel, each sensor streamer coupled to the tow vessel by a respective lead-in cable; towing, by the tow vessel, a plurality of lead vessels with each lead vessel pulling a respective seismic source, each lead vessel pulled by a respective tow cable and at least one intermediate cable; actuating the respective seismic sources pulled by the plurality of lead vessels; and gathering seismic data by each of the sensor streamers.

Systems and methods for removing galvanic distortion caused by near-surface inhomogeneities from surface-to-borehole (STB) measurements are disclosed. Corrected STB measurements may provide for a representation of the resistivity of an oil-bearing reservoir and may be used to determine movement of a waterfront within the reservoir caused by waterflooding of the reservoir.

A device for holding one or more seismic nodes during a seismic survey includes a body having an outer surface configured to be seated against a surface of the ground during the seismic survey. In addition, the device includes a first receptacle extending from the outer surface into the body. Further, the device includes a second receptacle extending from the outer surface into the body. Each receptacle has a central axis. A first reference plane containing the central axis of the first receptacle is oriented perpendicular to the central axis of the second receptacle.

The invention relates to a carrier (5) for transporting seismic nodes (9) to and from a sea floor (4), comprising an interior (8) for storing the nodes and a node transfer position (10) for transferring nodes (9) to and from the carrier (5); a support (14) for supporting the nodes (9) in a row (33) between the interior (8) of the carrier (5) and the node transfer position (10); and an endless driven belt or chain (11) with pushers (19) for pushing the row (33) of nodes (9). The invention also relates to a seismic node (9) adapted to use in the carrier (5). Further the invention relates to a method for loading seismic nodes (9) into the carrier (5), and a method for unloading seismic nodes (9) from the carrier (5).

The present invention concerns a method for determining the optimum positioning of source-receiver pairs capable of acquiring seismic data, comprising: a first step of identifying a zone of interest having been the subject of an earlier seismic acquisition, in order to obtain an image of the subsoil of same; a second step of obtaining seismic data acquired during the earlier seismic acquisition of said zone of interest during a time of interest; a third step of applying a partial or total demigration of seismic data, in order to determine the positions of each source-receiver pair having contributed to the image of said subsoil of said zone of interest during said time of interest; a fourth step of obtaining unprocessed traces for said source-receiver pair positions; a fifth step of selecting at least one optimum unprocessed trace from among said unprocessed traces; and a sixth step of determining the source-receiver pair positions corresponding to said at least one optimum unprocessed trace.

A seabed object detection system is provided. The system can include a receiver array. The receiver array can include a plurality of receivers disposed on a plurality of streamers. The plurality of streamers can include a central port side streamer, a central starboard side streamer, an auxiliary port side streamer and an auxiliary starboard side streamer. The system can include a source array. The source array can include a plurality of sources. The plurality of sources can include a central port side source, a central starboard side source, an auxiliary port side source, and an auxiliary port side streamer. The source array towed during a first pass can define a first path. The source array towed during a second pass can define a second path. The first path can be interleaved with the second path such that the first path overlaps the second path.