Patent ID: 7221620

Claim:
An apparatus for seismic measurements, comprising: a seismic source; a plurality of streamers having hydrophone devices, said seismic source and said plurality of streamers being towed behind a vessel; a pair of deflectors submerged in the sea; a wire fastened between the deflectors, said wire limiting spacing between and outward movement of the deflectors transverse to a direction of travel of the vessel as the vessel moves, said plurality of streamers mounted on said wire with a spacing therebetween in a range of 1 to 25 meters, said wire when stretched between the deflectors causing the streamers attached thereto to maintain a set spacing, said plurality of streamers extending parallel to the vessel's direction of travel and having a lengthwise extent that is 25% to 400% of the spacing between the steamers with a minimum lengthwise extent of 25 cm and a maximum lengthwise extent of 100 meters; a hydrophone signal cable connecting said plurality of streamers together, said hydrophone signal cable extending along said wire, each streamer having m hydrophones, analog signals from said m hydrophones being summed up, the m hydrophone devices of each streamer forming a single-channel hydrophone device, a total of n streamers being mounted on the hydrophone signal cable, thereby forming a total of n single channel hydrophone devices; and an n-channel sampling device for sampling all the n single-channel hydrophone devices simultaneously.