Pgs Geophysical As

Karl Petter Elvestad

Einar Nielsen

Vidar Hovland

Tore Steinsland

Jan Erik Stokkeland

Michael Malling

Martin Austad

Wayne Russell Paull

A system can include a float, a winch, a line, and a collapsible fairing. The winch can be coupled to the float. The line can be associated with the winch, where the winch is configured to extend and retract the line. The collapsible fairing can surround the line. Extension and retraction of the line can cause the collapsible fairing to extend and collapse.

Collapsible fairing

Techniques are disclosed relating to marine geophysical prospecting. According to some embodiments, a survey vessel may tow a streamer through a body of water. If the streamer needs to be maintained (e.g., cleaned, repaired, or serviced), a second vessel may lift the streamer out of the water for this purpose. Techniques are disclosed that are relevant to the handling of protruding members (such as streamer steering devices) on the streamer.

Marine streamer handling

Valves. At least some of the example valves include: a valve body; a valve housing; and a piston that defines a proximal end and a distal end, the piston disposed in a piston bore of the valve housing. The valve defines a closed orientation by a first rotational orientation of the valve housing relative to the valve body, and the valve defines an open orientation by a second rotational orientation of the valve housing distinct from the first rotational orientation.

Method and system of a valve

Buoy for marine surveys. At least some of the illustrated embodiments are a buoy including an elongated main body and a mast system coupled to the elongated main body. The mast system includes: a forward mast; an aft mast; a spanning portion coupled between a distal end of the forward mast and a distal end of the aft mast; and an aperture defined at least in part by the main body, forward mast, aft mast, and spanning portion. The buoy is configured to float in water such that the water level intersects the forward mast and aft mast, the elongated body is submerged, and the spanning portion resides above the water level.

Buoy for marine surveys

A steerable seismic energy source includes at least one float. The floatation device includes a device for changing buoyancy thereof. A frame is coupled to the at least one float. At least one seismic energy source is suspended from the frame. At least one steering device is coupled to the floatation device or the frame. The at least one steering device includes at least one control surface and a control surface actuator coupled to the control surface. The actuator is configured to rotate the control surface to generate hydrodynamic lift at least in a vertical direction.

Depth steerable seismic source array

Techniques are disclosed herein relating to distribution of fluids. These techniques may be useful in, for example, supplying pressurized air to seismic sources (or arrays of seismic sources), such as those used in marine seismic operations. Some embodiments of this disclosure include a pipe that passes through a fluid distribution block. The pipe may be configured such that it is able to slide along and/or twist about a longitudinal axis of the distribution block. This technique may reduce the effects of the various stresses that may operate on marine seismic source equipment as it is towed through a body of water.

Fluid distribution device

A compound buoy. At least some of the illustrative embodiments are buoy systems that include: a surface buoy; a subsurface buoy comprising an elongated outer body; a connector disposed on the lower surface; and a winch having a line, the line coupled between the surface buoy and the subsurface buoy. The buoy system has first configuration in which the upper surface of the subsurface buoy abuts the surface buoy, the abutting relationship held by tension in the line, and the buoy system has a second configuration where a distance between the surface buoy and the subsurface is limited by a length of the line spooled off the winch. In operation, the subsurface buoy supports more of the subsurface load than the surface buoy.

Method and system of a compound buoy

A seismic source array includes at least one float. A plurality of rigid conduit sections each includes a bracket for suspension from the float at a selected depth in a body of water and configured to suspend a seismic energy source therefrom. At least one bend strain relief is coupled between adjacent rigid conduit sections. Each bend strain relief includes a coupling at each longitudinal end. Each bend strain relief includes woven fiber molded into flexible plastic for transmitting axial loading while absorbing bending and torsional stress. A seismic energy source is suspended from each bracket. Lines for operating the seismic energy sources pass through the rigid conduit sections and the at least one bending strain relief.

Coaxial support structure for towed marine seismic source arrays

A method for towing a sensor streamer array in a body of water includes towing a plurality of sensor streamers behind a vessel in the water, measuring tension at a plurality of positions along the array and determining at least one of an optimum operating speed for the vessel, when the streamers and associated towing equipment have become affected by marine debris so as to require cleaning, and an optimum angle of attack of at least one paravane in the towing equipment.

Growing community of inventors

Trogstad, Norway

Karl Petter Elvestad