Abstract: A detention unit is provided for retrieval of an elongated body (9), such as a cable. The unit includes two or more movable friction surfaces (1, 11) adapted to pull in the elongated body (9). The moveable friction surfaces (1, 11) are arranged relative to each other so that the elongated body (9) may bear or rest against at a part of at least two friction surfaces (1, 11) in a sequential manner. The part of the friction surfaces (1, 11) adapted to pull the elongated body (9) defines a arc section, and each friction surface is provided with a separate propulsion unit (3, 14).

Abstract: A device for retrieving ocean bottom seismic cable as the cable is pulled up from the bottom and hauled aboard a vessel. The cable is first led over a front wheel located on an arm which is pivotally mounted for movement about an axis. The cable is then passed under a second wheel before it is brought aboard the vessel, optionally via one or more additional wheels. A damper is provided between a fixed point on the arm, spaced apart from the axis and a fixed point on the vessel, so that the front wheel is raised in response to lower tension in the cable and is lowered in response to an increase in tension in the cable, thereby counteracting any variations in the tension of the cable.

Abstract: A device for storing ocean bottom seismic cable (1) on board a vessel, which comprises a rack (11) positioned so that the cable (1) can be hung up thereon, moreover, a device for deploying cable stored on the aforementioned device is described, where as an extension to the rack (11) there may be provided an element (18) for guiding the cable (1) astern from the rack and releasing the cable (1) behind the vessel, and also a regulator (19) for controlling the deployment speed of the cable.

Abstract: A float for use in seismic surveys of the sea bed supports a plurality of seismic pulse transmitters (6) which are suspended on lines (7) beneath the float (1). At a distance from the front end of the float (1), on one sidewall thereof, a fastening device for a towing cable and a lead-in for control lines and lines for supplying operating medium to the pulse transmitters are provided. These lines and cables are gathered in a common line (3) which extends behind the tow ship. The line (3), at a distance away from the float (1), is connected to a line (4) which leads to a length-regulating device (12) inside the front section of the float. The float is also provided with at least one motor (10) with a drive shaft (9)leading to hoisting drums (8) for the lines (7) to the respective seismic pulse transmitters (6). Both the motors (10, 12) and the seismic pulse transmitters (6) are connected to the pneumatic supply line.

Abstract: An arrangement for spacing a floating body from a mother vessel during borehole-seismic measurements, wherein the floating body includes at least two buoyant bodies connected by a rigid framework and which supports the seismic equipment, the floating body is maintained in a correct position for transmitting seismic pulses by a crane or boom mounted on the mother vessel, a tube or hose system is mounted on the framework for ejecting a pressurized medium, preferably water, against the side of the vessel through nozzles, and the pressurized medium is transferred to the system through a hose coupled to a source of pressurized fluid on board the vessel.

Abstract: A float for use in seismic surveys of the sea bed supports a plurality of seismic pulse transmitters (6) which are suspended on lines (7) beneath the float (1). At a distance from the front end of the float (1), on one sidewall thereof, a fastening device for a towing cable and a lead-in for control lines and lines for supplying operating medium to the pulse transmitters are provided. These lines and cables are gathered in a common line (3) which extends behind the tow ship. The line (3), at a distance away from the float (1), is connected to a line (4) which leads to a length-regulating device (12) inside the front section of the float. The float is also provided with at least one motor (10) with a drive shaft (9) leading to hoisting drums (8) for the lines (7) to the respective seismic pulse transmitters (6). Both the motors (10, 12) and the seismic pulse transmitters (6) are connected to the pneumatic supply line.

Abstract: An assembly for use in seismic surveys of the sea bed is towed behind a vessel and comprises groups of seismic signal transmitters which are towed through the water, being suspended from float buoys which are combined to form one body which may be formed as a sleeve having limited flexibility. The body is formed with a head member shaped for reducing resistance to the water, and connected to a coupling point for a tow wire to the vessel, which point lies forward of the head member and at the same depth as the transmitters.