Abstract: An apparatus for acquiring survey data including streamer equipment comprising a lead-in cable; and a geophysical streamer with a plurality of geophysical sensors distributed along the geophysical streamer, including a forward geophysical sensor; a depressor coupled to the streamer equipment in front of the forward geophysical sensor; a variable tension control device coupled at a back end of the geophysical streamer; and a plurality of tension control system sensors. A method for acquiring survey data including obtaining data from tension control system sensors of a geophysical streamer system; identifying an adjustment to be made to one or more tension control factors of the geophysical streamer system to reduce or control vibrational behavior of streamer equipment of the geophysical streamer system making the adjustment to the one or more tension control factors; and acquiring survey data with the geophysical streamer system.

Abstract: Techniques are disclosed relating to geophysical surveying. In some embodiments, an added unique fold parameter is determined for one or more bins during a survey of a geophysical formation. In some embodiments, the position of one or more elements of a survey system is adjusted based on the added unique fold. In some embodiments, a ratio of the determined added unique fold to a theoretically obtainable added unique fold is determined, and the adjustment may be based on this ratio. In some embodiments, an acceptability parameter is also considered. In some embodiments, survey elements may be steered to increase added unique fold without leaving coverage holes that violate an acceptability criterion. In some embodiments, the steering is performed automatically. In some embodiments, coverage parameters are graphically displayed to an operator.

Abstract: An apparatus for acquiring survey data including streamer equipment comprising a lead-in cable; and a geophysical streamer with a plurality of geophysical sensors distributed along the geophysical streamer, including a forward geophysical sensor; a depressor coupled to the streamer equipment in front of the forward geophysical sensor; a variable tension control device coupled at a back end of the geophysical streamer; and a plurality of tension control system sensors. A method for acquiring survey data including obtaining data from tension control system sensors of a geophysical streamer system; identifying an adjustment to be made to one or more tension control factors of the geophysical streamer system to reduce or control vibrational behavior of streamer equipment of the geophysical streamer system making the adjustment to the one or more tension control factors; and acquiring survey data with the geophysical streamer system.

Abstract: Techniques are disclosed relating to geophysical surveying. In some embodiments, an added unique fold parameter is determined for one or more bins during a survey of a geophysical formation. In some embodiments, the position of one or more elements of a survey system is adjusted based on the added unique fold. In some embodiments, a ratio of the determined added unique fold to a theoretically obtainable added unique fold is determined, and the adjustment may be based on this ratio. In some embodiments, an acceptability parameter is also considered. In some embodiments, survey elements may be steered to increase added unique fold without leaving coverage holes that violate an acceptability criterion. In some embodiments, the steering is performed automatically. In some embodiments, coverage parameters are graphically displayed to an operator.

Abstract: A firearm comprising a frame, a barrel joined to the frame, and a cartridge magazine selectively joinable to the frame; at least one cartridge contained within the cartridge magazine with the cartridge having a casing and at least one projectile, the casing having a cartridge case flange at one end and a mouth on the opposite end; and mechanism for lifting in selective communication with the cartridge and the barrel, with the mechanism for lifting having a ramp that is located adjacent to the end of the cartridge at the cartridge case flange, where the ramp acts selectively on the flange and casing; an extractor rib and barrel rib cooperating to keep extractor locked during cartridge ignition and unlocked substantially after ignition.