Abstract: The present invention relates to the field of marine towing operations for marine seismic survey systems and seismic data gathering. More specifically, the present invention relates to seismic sources and receiver sensor cables, streamers, floats etc., that have means for adjusting and keeping a desired position in an array during a tow behind a vessel. The apparatus comprises a pulley apparatus, being a kind of miming block (1), connected with and supporting marine equipment (3, 3?). The miming block (1) is configured to attach to the deflected lead wire or tow wire (2, 9). It has means for traveling along the wire (2, 9).

Abstract: The present invention relates to the field of marine towing operations for marine seismic survey systems and seismic data gathering. More specifically, the present invention relates to seismic sources and receiver sensor cables, streamers, floats etc., that have means for adjusting and keeping a desired position in an array during a tow behind a vessel. The apparatus comprises a body (10) with means for being towed behind a vessel, means for connecting with and supporting and steering submerged marine seismic equipment laterally in the water and means for remote control from vessel. The body (10) of the apparatus has a forward positioned float unit (16) with an elongated rear float (12) hinged at the rear of the forward float. The forward float unit has vertical wings (18, 18?) with means for adjusting angle of attack in water.

Abstract: A positioning system (100) for marine seismic surveying, comprising a towing vessel (110), a source array (120) and a receiver array (130) with several streamers (131). Each streamer (131) comprises at least three birds (134) and positioning sensors (134-137) wherein several seismic receivers (132) are placed between each pair of birds (134). The system (100) comprises a dynamic model wherein each streamer (131) is represented by a fitted B-spline curve and each bird (134) is associated with a constant velocity and a constant acceleration; and a Kalman filter using the dynamic model and observations from the positioning sensors (134-137) to provide a geodetic position of each seismic receiver (132) with better accuracy than the dynamic model alone and observations alone within a time interval ?t equal to or less than a minimum time between shots determined by the source array (120).

Abstract: The invention provides a system (100) for marine seismic surveying, comprising a towing vessel (110) with a controller, a source array (120) and a receiver array (130) with several streamers (131). The source array (120) comprises n>4 identical subarrays (121) configured as at least (n?1) seismic sources S1, . . . , Sn-1, wherein adjacent subarrays (121) are part of at least two sources Si, Sj at different times.

Abstract: The invention concerns a system (100) for detecting pollution (2) on or at a sea surface (3), wherein the system (100) is adapted for mounting on a marine vessel (1). The system comprises a detector (110) with a LIDAR for providing digital pollution data (112) relating to pollution (2) in a region (40) along a path (4) travelled by the marine vessel (1); a positioning system (120) for providing positioning data; a clock (131) for providing a digital timestamp; and a computer (130) for collecting, combining and storing digital data (141). The computer (130) is configured to execute a secure hashing algorithm (133) on pollution data (112) with associated positioning data and a timestamp to produce a digest, execute an encryption function (134) on the digest using a private key (sk) and to store the data (141) and encrypted digest (142) in a database (140).

Abstract: A cable fairing (fairing) (40) for reducing the flow resistance for a cable (45) has a wing formed cross section with a wide, rounded front and a tapered tail, a through-going cable channel (46) for the cable (45) perpendicular to the cross section of the widest part of the cross section. The wing profile comprises an elastic material of sufficient stiffness to maintain the shape when it is towed thereby causing flow resistance. The cable fairing (40) has slots (42) cut into the elastic material from the tail towards the cable channel (46), so that the tail comprises slats (41) which can be bent parallel to the cable channel (46) to reduce the cross-section of the cable fairing. By this is low flow resistance, as from a stiff cable jacket, combined with sufficient elastic deformability so the cable (45) with attached cable fairings (40), can be winched and pass through narrow openings in the deployment and retrieval, and wound onto a reel for storage and transport.

Abstract: The invention relates to a seismic streamer (1) for underwater towing at a towing speed in ice-free or wholly or partially icy water, the streamer (1) is provided with birds (2) spaced along the streamer, the streamer including the birds (2) has negative buoyancy, the birds have wings (8) which can be set so that the birds during movement in the water apply an upward or downward force on the streamer. The streamer (1) is provided with buoyant bodies (4) spaced along the streamer, the buoyant bodies are connected to the streamer by spacer elements (5), the streamer including the birds, the buoyant bodies with associated spacer elements and any other equipment together have positive buoyancy. The invention also relates to a corresponding method for securing a seismic streamer (1) from damage at a substantial reduction or cessation of towing speed when towing underwater in ice-free or wholly or partially icy water.

Abstract: A seismic data acquisition system comprising a composite marine seismic cable and a winch, the composite marine seismic cable comprising a sensor cable and a lead-in cable for providing electrical connections to the sensor cable, and the winch comprising a first cable compartment for the lead-in cable and a second cable compartment for the sensor cable, wherein the lead-in cable and the sensor cable may be deployed or recovered independently of each other.

Abstract: A bend stiffener (7) is described, which surrounds the end portion of an elongate, essentially cylindrical object, as for instance a flexible pipe (2) or a cable, extending from a subsea installation to a surface vessel, and is connected to an end piece (1) or end flange of the pipe (2) at a connection to the vessel, wherein the bend stiffener (7) is provided by a plurality of inner, essentially cylindrical clamps (5) made having a longitudinal groove (8) for receiving spring rods (3) in their outer surface, which clamps (5) surround the pipe (2), and there is provided a plurality of outer, essentially cylindrical clamps (6) which in their inner surface are made having longitudinal grooves (8) for receiving the spring rods (3), the grooves (8) in the inner and outer clamps (5, 6) corresponding to each other when the outer clamp (6) is mounted around the inner clamp (5), and a plurality of clamp sets (5, 6) are arranged spaced apart from each other in vicinity of the end piece (1), the spring rods (3) being se