Abstract: The present invention relates to streamer cables. One embodiment of the present invention relates to a method for preparing a streamer cable. The method may comprise retrofitting the streamer cable with a solid void-filler material, where the streamer cable was configured as a liquid-filled streamer cable. The retrofitting may comprise introducing a void-filler material into the streamer cable when the void-filler material is in a liquid state and curing or otherwise solidifying the void-filler material to a solid state. In another embodiment, the present invention relates to a streamer cable comprising an outer skin and-at least one sensor positioned within the outer skin. The streamer cable may also comprise a solid void-filler material positioned between the outer skin and the at least one sensor, wherein the solid void-filler material is coupled to the at least one sensor.

Abstract: Embodiments described herein relate to an apparatus and method for deployment and retrieval of one or more seismic devices in a deep water marine environment. In one embodiment, a method for deploying and positioning ocean bottom equipment is described. The method includes attaching at least one article having a negative buoyancy to a support cable, lowering the at least one article into the water column from two or more points of suspension on a surface of the water column, at least one of the two or more points of suspension being movable relative to the other point of suspension, and manipulating tension of the support cable, length of the support cable, position of the support cable, and distance between the two or more points of suspension to cause the at least one article to fall to a bottom of the water column at a predetermined location on the bottom.

Abstract: A geophysical sensor cable has one or more sensor cable sections. Each of the sensor cable sections is provided with seismic and electromagnetic sensors arranged along said cable. The seismic sensors include a hydrophone and a seismic component receiver for seismic vector measurements while the sensor cable is at the sea-floor. The electromagnetic sensors include both E-field sensors and H-field sensors. The E-field sensors include pairs of first and second electrodes arranged with different positions along the cable and connected to a voltage amplifier. The H-field sensors include three mutually orthogonally arranged H-field component sensors.

Abstract: A system for towing a marine geophysical sensor streamer includes a lead in line extending from a tow vessel. A streamer front end termination is coupled to an end of the lead in line and to a forward end of the sensor streamer. A floatation device is coupled by a line proximate to the front end termination. A winch is disposed on the floatation device to extend and retract the line. A depth sensor is disposed proximate the front end termination. A controller is in signal communication with the winch and the depth sensor so that the forward end of the streamer is maintained at a selected depth in the body of water.

Abstract: A technique for acquiring wide azimuth seismic data using simultaneous shooting is presented in which a plurality of seismic sources are positioned to achieve a desired crossline sampling as a function of the number of passes. This is accomplished by “interleaving” sources as deployed in the spread, as positioned in multiple passes, or some combination of these things, to achieve an effective shotline interval during acquisition or an effective crossline sampling less than their crossline source separation.

Abstract: Methods and apparatus for cable termination and sensor integration at a sensor station within an ocean bottom seismic (OBS) cable array are disclosed. The sensor stations include a housing for various sensor components. Additionally, the sensor stations can accommodate an excess length of any data transmission members which may not be cut at the sensor station while enabling connection of one or more cut data transmission members with the sensor components. The sensor stations further manage any strength elements of the cable array.

Abstract: The present invention provides a method and apparatus for determining the position of a seismic cable being used to perform a marine seismic survey. The apparatus includes at least one seismic sensor and a plurality of sources deployed in a manner that is structurally independent of the seismic sensors and adapted to provide a positioning signal distinguishable from a seismic survey signal to the seismic sensors.

Abstract: A method and apparatus for acquiring seismic signals from beneath a salt region in the earth. In one embodiment, the method includes tuning an air gun array to a first bubble oscillation; towing the air gun array in the water at a depth of at least 10 meters, in which the air gun array has a total volume in a range of about 6780 cubic inches to about 10,170 cubic inches; directing acoustic signals with the air gun array down through the water into the earth beneath the salt region; towing one or more seismic streamers in the water at one or more depths, in which at least one of the depths is at least 10 meters, in which each streamer comprises a plurality of hydrophones disposed therealong; and recording with the hydrophones seismic signals reflected from strata in the earth beneath the salt region.

Abstract: A method for marine seismic surveying includes towing seismic sensors in a plurality of streamers in the water, actuating a seismic energy source in the water at selected times and detecting seismic signals at the sensors resulting from the actuation of the source. A data trace is created for each of the detected signals. At least one Fresnel zone is determined for at least some of the seismic data traces. A contribution of each of the traces to each one of a plurality of bins defined in a predetermined pattern is computed, based on the Fresnel zone associated with each trace. Based on the computed contributions, a maximum lateral distance between corresponding seismic sensors is determined that will result in a contribution sum above a selected threshold.

Abstract: A system comprises towed marine seismic equipment marine seismic equipment, adapted for towing through a body of water; and a surface covering, with longitudinal ribs, attached to the marine seismic equipment to reduce drag. A method comprises towing marine seismic equipment having a surface covering, with longitudinal ribs, attached thereto to reduce drag.

Abstract: An apparatus includes a streamer cable having one or more seismic devices disposed within a polymer body and about a core. The polymer body includes a channel defined therein for receiving one or more wires connecting the seismic devices. The wires include slack for withstanding the tensional forces experienced by the streamer cable during deployment and operation. Associated methods are also described.

Abstract: A technique facilitates performance of seismic surveys in a variety of land and marine environments. The technique employs one or more optical fibers designed for deployment in a seismic survey region. Each optical fiber comprises multiple seismic sensors that are formed in the optical fiber, and those multiple seismic sensors are utilized in detecting reflected seismic signals.

Abstract: A technique includes performing at least one intervening towed seismic survey after a prior towed seismic survey and before a future towed seismic survey. The prior towed seismic survey has associated first streamer positions, and the future towed seismic survey has associated second streamer positions that do not coincide with the first streamer positions. The technique includes using measurements that are acquired in the intervening towed seismic survey(s) to link the prior towed seismic survey to the future towed seismic survey for time lapse analysis involving the prior and future towed seismic surveys.

Abstract: A method and control device for controlling the position of a marine seismic streamer spread and the ability for controlling individual marine seismic streamers both in shape and position relative to other marine seismic streamers and thereby counter effects from crosscurrent or other dynamic forces in a towed spread behind a seismic survey vessel. The system includes sensor means for determining information to control the streamer and a control device 10, including a housing 11 mechanically and at least partly electrically connected in series between two adjacent sections of the streamer 13, at least three control members 20 projecting from the housing 11, and control means adjusting the respective angular positions of the control members 20 so as to control the lateral and vertical position of the streamer 13.

Abstract: A method and apparatus for a seismic cable is described. The apparatus includes a plurality of cable segments comprising at least a first cable segment and a second cable segment coupled by a connector. The connector comprises a cylindrical body having a first diameter, a portion of the body having a second diameter that is smaller than the first diameter and centrally positioned between opposing ends of the body, a first coupling section having a terminating end of the first cable segment anchored therein, and a second coupling section having a terminating end of the second cable segment anchored therein, at least a portion of the first and second coupling sections being rotatably coupled to respective ends of the body, wherein the connector isolates the first cable segment from the second cable segment. A method of deployment and retrieval of the seismic cable is also described.

Abstract: A technique includes receiving seismic data acquired by an array of seismic sensors during a towed marine survey of a subsurface and performing migration velocity analysis to determine a background velocity model of the subsurface based at least in part on particle motion derived from the seismic data.

Abstract: A marine cable for seismic surveys is described with a plurality of ceramic pressure sensors arranged in groups of at least two pressure sensors with a group output being representative of the vertical pressure gradient at the group location, and an inclinometric system including one or more transducers for determining the orientation of the sensors of the group in order to determine their true vertical separation.

Abstract: A seismic streamer includes a jacket covering an exterior of the streamer. At least one strength member extends the length of the jacket. The strength member is formed as a substantially flat belt having a width to thickness ratio of at least 10. At least one sensor holder is coupled to the at least one strength member. The at least one sensor holder includes at least one arcuate opening for receiving the at least one strength member. The at least one arcuate opening is laterally displaced from a center of the at least one sensor holder such that when the at least one strength member is disposed therein the at least one strength member is substantially tube shaped and substantially coaxial with the jacket.

Abstract: A system and method for deployment of a plurality of seismic recorder assemblies from a survey vessel on the ocean bottom is disclosed. The seismic recorder assemblies are self contained, autonomous nodal devices which are capable of receiving and recording reflected seismic energy and storing the data locally while operating for an extended period of time. The assemblies each have two or more attachment points for the connection of separate connecting cable segments.

Abstract: An apparatus includes a streamer having one or more seismic data acquisition devices enclosed within a skin. The skin has a modulus of elasticity of at least 30 MPa to attenuate a flow noise.

Abstract: An apparatus includes a streamer having one or more sensor holders for retaining seismic sensors therein. A housing is disposed about a sensor with a gel-like material disposed between the housing and the sensor, thereby decoupling the sensor from its surroundings. The housing is disposed in the sensor holder and the streamer is filled with either liquid or another gel-like material.

Abstract: An apparatus includes a streamer having one or more sensor holders for retaining seismic sensors therein. The sensor holders have a reduced cross-sectional area to increase gel continuity and coupling through the streamer.

Abstract: A seismic streamer includes at least one array of sensors each disposed in a sensor holder at longitudinally spaced apart locations. A longitudinal orientation of at least one sensor or at least one sensor holder is different from that of the other sensors along the length of the array.

Abstract: A towed array is provided with hot-film sensors and anemometer circuitry to calculate the angle of inclination of the towed array in real time during deployment of the towed array in a sea water environment. The hot-film sensors are arranged in pairs along the length of the towed array to increase the sensitivity of the inclination angle determinations and are located flush with an exterior surface of the towed array to minimize interference with the operation of the towed array. The pairs of hot-film sensors determine the local shear stresses on the towed array, and these measurements are converted to inclination angles using an empirically derived look-up table.

Abstract: Systems and methods for automatic steering of marine seismic sources are described. One system comprises a marine seismic spread comprising a towing vessel and a seismic source, the seismic source comprising one or more source arrays each having a center of source array, each source array having one or more source strings; a seismic source deployment sub-system on the towing vessel, the sub-system controlled by a controller including a software module, the software module and the deployment sub-system adapted to control an inline distance between one of the centers of source array and a target coordinate. It is emphasized that this abstract is provided to comply with the rules requiring an abstract, allowing a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: A marine seismic exploration method and system comprised of continuous recording, self-contained ocean bottom pods characterized by low profile casings. An external bumper is provided to promote ocean bottom coupling and prevent fishing net entrapment. Pods are tethered together with flexible, non-rigid, non-conducting cable used to control pod deployment. Pods are deployed and retrieved from a boat deck configured to have a storage system and a handling system to attach pods to cable on-the-fly. The storage system is a juke box configuration of slots wherein individual pods are randomly stored in the slots to permit data extraction, charging, testing and synchronizing without opening the pods. A pod may include an inertial navigation system to determine ocean floor location and a rubidium clock for timing. The system includes mathematical gimballing. The cable may include shear couplings designed to automatically shear apart if a certain level of cable tension is reached.

Abstract: A cleaning robot may be provided having a case and a sensor assembly. The sensor assembly may include a sensor hole having a first opening provided at an outer surface of the case and a second opening provided inwardly of the first opening, with respect to a center of the case. Additionally, the sensor assembly may include a sensor element configured to receive a signal and the sensor element may be provided inwardly of the first opening.

Abstract: A seismic survey system includes at least one autonomously operated vehicle and at least one seismic energy source associated with the autonomously operated vehicle. The autonomously operated vehicle includes a controller programmed to operate the at least one seismic energy source at selected times and to cause the autonomously operated vehicle to follow a predetermined geodetic path.

Abstract: A technique includes obtaining first data indicative of seismic measurements acquired by seismic sensors of a first set of towed streamers and obtaining second data indicative of seismic measurements acquired by seismic sensors of a second set of towed streamers. The second set of towed streamers is towed at a deeper depth than the first set of towed streamers. The technique includes interpolating seismic measurements based on the first and second data. The interpolation includes assigning more weight to the second data than to the first data for lower frequencies of the interpolated seismic measurements.

Abstract: A technique includes obtaining different sets of data, which are provided by seismic sensors that share a tow line in common. Each data set is associated with a different spatial sampling interval. The technique includes processing the different sets of data to generate a signal that is indicative of a seismic event that is detected by the set of towed seismic sensors. The processing includes using the different spatial sampling intervals to at least partially eliminate noise from the signal.

Abstract: An anti-biofouling seismic streamer casing (100,100?) is provided that is formed by a flexible tubing (110) coated with a layer of a two-part heat cured silicone elastomer (120). The seismic streamer casing (100, 100?) is formed by a method that includes steps of providing a flexible tubing (200) and pre-treating the outer surface of the tubing (210). Two parts of a two-part silicone elastomer are then mixed together (220). The method also includes coating the mixed two-part silicone elastomer on the flexible tubing (230), and heating the flexible tubing to cure the coating (240).

Abstract: A system comprises towed marine geophysical equipment, adapted for towing through a body of water; and a surface covering, comprising a textural attribute of shark skin, attached to the marine geophysical equipment. A method comprises towing marine geophysical equipment having a surface covering, comprising a textural attribute of shark skin, attached thereto.

Abstract: A method for acquiring three-dimensional seismic data for sub-surface geologic features wherein a seismic source array is moved along a survey pattern having a plurality of source lines of unequal lengths that are substantially parallel to each other and intersect a receiver line. The survey pattern can be repeated in an overlapping and interleaved fashion to survey a larger area.

Abstract: A technique for seismic surveying is presented in which a towed array, marine seismic spread, includes a plurality of streamers and a deflector system. The deflector system laterally spreads the seismic streamers, wherein at least one streamer in the spread is deflected using more than one deflector attached to the tow cable or streamer, and where the deflectors are not connected to a float on the sea surface. Other aspects of the technique include methods for towing such a spread and for controlling such a spread. Still other aspects include computing resources which may be used to perform the methods.

Abstract: A method for operating marine seismic vibrators includes towing at least a first and a second marine seismic vibrator in a body of water beneath the hull of a vessel. At least a third marine seismic vibrator is towed at a selected depth in the water other than beneath the hull of the vessel. The at least first, second and third vibrators are operated to sweep through respective frequency ranges. The first and second frequency ranges have lowermost frequencies and uppermost frequencies respectively differing by a selected sub-harmonic frequency range. The third frequency range has a lowermost frequency at least equal to the uppermost frequency of one of the first and second frequency ranges and traverses a seismic frequency range of interest.

Abstract: A towed array is provided with hot-film sensors and anemometer circuitry to calculate the angle of inclination of the towed array in real time during deployment of the towed array in a sea water environment. The hot-film sensors are arranged in pairs along the length of the towed array to increase the sensitivity of the inclination angle determinations and are located flush with an exterior surface of the towed array to minimize interference with the operation of the towed array. The pairs of hot-film sensors determine the local sheer stresses on the towed array, and these measurements are converted to inclination angles using an empirically derived look-up table.

Abstract: According to the present invention there is provided a vibration isolation section for use in a seismic streamer system, the section including: a resilient sheath arranged to be connected end-to-end in a seismic streamer system and receive axial loads transmitted through the system, wherein the resilient sheath is configured to stretch upon receiving an axial load and substantially convert the axial load into a radial stress; and a support structure housed within the resilient sheath, the support structure including one or more members having substantially constant diameter under load which provides a reaction to the radial stress, thereby providing attenuation to the received axial load.

Abstract: A method of acquiring or processing multi-component seismic data obtained from seismic signals propagating in a medium, the method comprising the steps of: selecting a first portion of the seismic data in which the first arrival contains only upwardly propagating seismic energy above the seafloor; and determining a first calibration filter from the first portion of the seismic data, the first calibration filter being to calibrate a first component of the seismic data relative to a second component of the seismic data.

Abstract: The present invention relates to a seismic cable (3) comprising at least two sensor nodes (4), the cable being adapted to lie permanently on a seabed (5). By covering each sensor node (4) and a length of the cable (3) connecting the sensor nodes (4) with a flexible protective socket (7), there is obtained a leak-tight connection, whereby penetration of water and/or moisture into the components of the sensor node (4) is not permitted.

Abstract: There is described an optical seismic cable (2) comprising a number of sensor units (5) spaced along the length of the cable and a number of connection units (4) spaced along the length of the cable, the cable further comprising a number of first optical fibres extending substantially continuously along the cable from one connection unit to the next, and a number of second optical fibres which each extend part-way along the cable between adjacent connection units, and wherein at each connection unit at least one first optical fibre is joined to a second optical fibre, and wherein at the sensor units sensors are joined to said second optical fibres.

Abstract: The present invention relates to streamer cables. One embodiment of the present invention relates to a method for preparing a streamer cable. The method may comprise retrofitting the streamer cable with a solid void-filler material, where the streamer cable was configured as a liquid-filled streamer cable. The retrofitting may comprise introducing a void-filler material into the streamer cable when the void-filler material is in a liquid state and curing or otherwise solidifying the void-filler material to a solid state. In another embodiment, the present invention relates to a streamer cable comprising an outer skin and-at least one sensor positioned within the outer skin. The streamer cable may also comprise a solid void-filler material positioned between the outer skin and the at least one sensor, wherein the solid void-filler material is coupled to the at least one sensor.

Abstract: A seismic streamer includes at least one elongated strength member. The seismic streamer further includes a substantially rigid sensor holder coupled to the strength member and fixed in position relative to the strength member. The streamer includes at least one particle motion sensor coupled to the sensor holder and fixed in position relative to the sensor holder.

Abstract: A technique includes generating a data stream that contains data acquired by nodes of a subterranean survey data acquisition network and introducing data into the data stream, which describes an equipment failure that occurred in the network.

Abstract: A system for a more efficient towing of a marine seismic array comprising one or more diverters attached to each lead-in cable. Because each lead-in cable has its own diverter, the need for dedicated towing ropes and taglines between lead-in cables is eliminated, thereby reducing the overall drag and fuel consumption. The diverters of the present invention are directly attached to the respective lead-in cables and are submerged, eliminating the need for taglines and additional flotation. The diverter of the present invention comprises of either a single span-wise hydro foil or two foil sections and is steerable. Similarly, the diverters of the present invention can be installed on the umbilical cables of seismic source subarrays to obtain the same benefits. As such, at least one diverter of the present invention can be attached directly to at least one umbilical cable of the seismic source subarray.

Abstract: Methods for efficiently acquiring full-azimuth towed streamer survey data are described. The methods use multiple vessels to perform coil shooting.

Abstract: A seismic streamer includes a jacket covering an exterior of the streamer. At least one strength member extends along the length of and disposed inside the jacket. At least one seismic sensor is mounted in a housing affixed to the at least one strength member. A void filling material fills the interstices inside the jacket. The housing is configured to isolate the at least one sensor from pressure variations in the void filling material, and the housing is configured to couple the at least one sensor to a body of water outside the streamer.

Abstract: A method for determining quality of signals acquired using marine seismic streamers having pressure responsive sensors and motion responsive sensors includes cross ghosting pressure responsive seismic signals and contemporaneously acquired motion responsive seismic signals. First filters are determined that cause the cross ghosted pressure responsive signals to substantially match the cross ghosted motion responsive signals. Second filters are determined that cause the cross ghosted motion responsive signals to substantially match the cross ghosted pressure responsive signals. The first and second filters are convolved and the convolution is used to determine signal quality.

Abstract: Seismic exploration techniques and the seismic imaging of subsurface layers, particularly apparatus for seismic exploration near the seafloor, are disclosed. The apparatus enables controlled depth towing of detectors to be carried out a short distance above the seafloor. The apparatus includes a streamer depth controller and at least one altitude keeper device, attached at intervals along the length of a towed streamer. The streamer carries detectors for measuring, for example, P- and S-waves in the seafloor.

Abstract: The technique disclosed herein includes a method and apparatus for controlling streamer steering devices to maintain a coil streamer shape that gives coverage for a coil shooting plan. The technique uses solved positions and a target coil streamer shape identified in the shooting plan to determine steering instructions to the streamer steering devices along the streamer.

Abstract: The present invention relates to streamer cables. One embodiment of the present invention relates to a method for preparing a streamer cable. The method may comprise retrofitting the streamer cable with a solid void-filler material, where the streamer cable was configured as a liquid-filled streamer cable. The retrofitting may comprise introducing a void-filler material into the streamer cable when the void-filler material is in a liquid state and curing or otherwise solidifying the void-filler material to a solid state. In another embodiment, the present invention relates to a streamer cable comprising an outer skin and at least one sensor positioned within the outer skin. The streamer cable may also comprise a solid void-filler material positioned between the outer skin and the at least one sensor, wherein the solid void-filler material is coupled to the at least one sensor.