Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Seismic source element modules can each include a seismic source element. Spacer modules can each have a hydrofoil shape. A first end of the spacer modules can be coupled to a respective first one of the seismic source element modules. A second end of the spacer modules can be coupled to a respective second one of the seismic source element modules. The source element modules and the spacer modules can collectively form a rigid structure.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.