A marine seismic acquisition system includes a frame that includes a central longitudinal axis and members that define orthogonal planes that intersect along the central longitudinal axis; a data interface operatively coupled to the frame; hydrophones operatively coupled to the frame; a buoyancy engine operatively coupled to the frame where the buoyancy engine includes at least one mechanism that controls buoyancy of at least the frame, the hydrophones and the buoyancy engine; and at least one inertial motion sensor operatively coupled to the frame that generates frame orientation data, where the hydrophones, the buoyancy engine and the at least one inertial motion sensor are operatively coupled to the data interface.

A marine seismic acquisition system includes a frame that includes a central longitudinal axis and members that define orthogonal planes that intersect along the central longitudinal axis; a data interface operatively coupled to the frame; hydrophones operatively coupled to the frame; a buoyancy engine operatively coupled to the frame where the buoyancy engine includes at least one mechanism that controls buoyancy of at least the frame, the hydrophones and the buoyancy engine; and at least one inertial motion sensor operatively coupled to the frame that generates frame orientation data, where the hydrophones, the buoyancy engine and the at least one inertial motion sensor are operatively coupled to the data interface.

Calibration based on twist and orientation for towed object can include determining an amount of twist as a function of length of a portion of a towed object based on output of tilt sensors in the portion of the towed object and a model that describes the twist along the portion of the towed object. An orientation of a seismic sensor can be determined based on the determined amount of twist and a position of the seismic sensor along a length of the portion of the towed object. The seismic sensor can be calibrated based on the orientation.

There is provided a spreading device (100) for trawl fishing and seismic survey operations. The device has an upper frame (111), an intermediate frame (113) and a lower frame (112). There are at least two upper panels (22, 23) between the upper and intermediate frames, and at least two lower panels (22, 23) between the intermediate and lower frames. One of the upper panels and one of the lower panels adjustable in its angle of attack with respect to other panels. There is provided a manual means for adjusting the angle of attack of the adjustable panels.

The presently disclosed technology relates to an arrangement for seismic acquisition where the spacing between adjacent pairs of receiver and sources lines is not all the same. Some receiver and/or source lines and/or receiver and/or source spacings are larger and some are smaller to provide a higher quality wavefield reconstruction when covering a larger total area or for a similar total area of seismic data acquisition, while providing a wavefield that is optimally sampled by the receivers and sources so that the wavefield reconstruction is suitable for subsurface imaging needs.

In the field of marine geophysical surveying, systems and methods for controlling the spatial distribution or orientation of a geophysical sensor streamer or an array of geophysical sensor streamers towed behind a survey vessel are provided. Various techniques for changing the spatial distribution or orientation of such geophysical sensor streamers in response to changing conditions are provided. For example, crosscurrent conditions may be determined based on configuration data received from positioning devices along the length of a streamer, and a new desired orientation for the streamer may be determined based on the crosscurrent conditions. The new desired orientation may include a new desired feather angle for the streamer.

A seismic streamer includes an outer sheath that forms an interior region of the seismic streamer of which a portion is filled with a gel or liquid. The streamer also includes at least one stress member placed off-center in the interior region, and multiple sensors mounted proximate to a center of the interior region, where the sensors include a pressure sensor and a motion sensor. The streamer further includes multiple tilt sensors mounted along the interior region. A method of manufacturing a seismic streamer includes placing at least one stress member off-center along a first direction, mounting multiple spacers along the stress member, and affixing sensors to respective spacers, where the sensors include a pressure sensor and a motion sensor. The method further includes mounting tilt sensors along the first direction and affixing an outer sheath to the streamer that forms an interior region of the seismic streamer.

A marine array having various embodiments of a modular foil system is disclosed. The modular foil system may be configured to generate lift when towed in a marine environment, and thus used to move, position, and/or depress instrument of the array. The modular foil system may include multiple groups of foil sections, each having an angle of attack that is adjustable relative to other groups of foil sections. For example, each group may be supported by a pair of through cables, and an actuator may adjust a tension in one or both of through cables, thereby alerting the angle of attack. The pair of through cables may converge toward one another at connection points adjacent opposing ends of a given group of foil sections of the modular system. The connection points thus establishing a modular framework to couple the given group to other groups of foils of the system.

A method includes: towing sources in a wide-tow source survey configuration; actuating at least one of the sources to create a signal; detecting the signal with a first receiver of a first plurality of streamers; and detecting the signal with a second receiver of a second plurality of streamers, wherein: the second plurality of streamers are interspersed with streamers from the first plurality of streamers in the port outer region and in the starboard outer region. A system includes: sources in a wide-tow source survey configuration and coupled to the survey vessel; a first plurality of streamers comprising a regular streamer spread and coupled to the survey vessel; and a second plurality of streamers coupled to the survey vessel, wherein: the second plurality of streamers are interspersed with streamers from the first plurality of streamers in the port outer region and in the starboard outer region.

A system for bridle bite adjustment can include a tow rope coupled to a paravane at a first position on a lever arm and a spur line coupled to the paravane at a second position on the lever arm. The system can also include a winch to adjust a deployed length of the tow rope. The tow rope and the lever arm can adjust a bridle bite of the paravane by when the deployed length of the tow rope is adjusted by the winch, thereby balancing tension between the tow rope and the spur line.