Paravane for floating barrier A paravane (20) including at least one foil with a first side, a second side, a leading end, a trailing end, a top and a bottom, wherein at least one foil is straight (1) and at least one second foil is curved (2), where one side of the straight foil and the other side of the curving foil are interconnected by a number of stays (3), where at least one foil is connected at the top to at least a first buoyant body (10) and that at least the one plane at the bottom is connected to at least one ballast element (13), and that at the second side of the straight foil there are at least one towline (8) and a tow eye (9) by which there is achieved a paravane (20) that can keep an arrangement of lines, nets, floats in a water body in a position suitable for performing the task.

A body towed by a cable behind a ship and commonly referred to as a towfish, the towfish includes a structure configured to move through the water in a horizontal main direction and at least one appendage configured to generate on the towfish a downwardly directed hydrodynamic lift (P) when the towfish is moving through the water under the effect of the towing, the appendage being orientable so as to modify its lift. The towfish comprises a bracket capable of rotational movement with respect the structure about a horizontal axis perpendicular to the horizontal main direction, the cable being attached to the bracket. An orientation (γ) of the appendage, allowing it to alter the lift (P), is dependent on an angle (β) formed between the bracket and the structure about the horizontal axis.

A seismic data acquisition positioning apparatus is provided. The apparatus can include a seismic data acquisition unit. The unit can include a case having an internal compartment. The unit can include a power source, a clock, a seismic data recorder, a control unit, and at least one sensor disposed within the case. The apparatus can include a hanging unit including a beacon unit. The apparatus can include a connector having a first end coupled with the seismic data acquisition unit and having a second end coupled with the hanging unit. The connector can pivot about the first end of the connector.

A vessel system includes a hull configured to provide buoyancy, one or more seismic sources configured to generate seismic energy, and a deployment apparatus configured to deploy the seismic sources from the hull to a water body or water column. A control system can be configured to operate the deployment apparatus, in order to deploy the seismic sources.

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 stable towable submersible device includes a rigid body that is towed at a positive pitch angle relative to the device's direction of motion. An acoustic projector housing extends vertically from the rigid body. When the rigid body rolls about its roll axis, which is tilted at the positive pitch angle, the acoustic projector rolls about the roll axis changing the acoustic projector's angle of attack relative to the direction of motion and generates a restoring force causing the acoustic projector to rotate back to a generally vertical orientation.

A foil for a towed cable includes a body defining at least two conduits. The body has a foil shape having a leading edge and a trailing edge. The foil shape defines a first surface extending between the leading edge and the trailing edge configured to provide lift. The foil shape defines a second surface opposed to the first surface extending between the leading edge and the trailing edge. The foil shape defines first and second lateral sides that extend between respective lateral edges of the first and second surfaces, the leading edge, and the trailing edge. A first conduit is defined within the forward half of the body adjacent to the leading edge, is open to each of the first and second lateral sides, and is configured to receive a cable therethrough. A second conduit may be defined within the body and filled with buoyant material.

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.

A lift based acoustic source is towable in an undersea environment by a towing vessel. A controller provides a combined lift control signal and an acoustic source signal. A control cable is joined between the towing vessel and a towed depressor having an active lift control system. The combined signal is used to control the towed depressor active lift control system. The towed depressor lift fluctuates in response to the source signal to generate the undersea acoustic signal. A hydrophone or hydrophone array can be provided for measuring the generated acoustic signal for feedback and monitoring.