Abstract:
An apparatus and method for 3D seismic exploration for use in a small ship. The apparatus includes a seismic source towed by the small ship from a rear side thereof, a pair of support rods connected to the rear side and horizontally arranged in two rows behind the seismic source in the direction extending from a sailing direction of the ship, and a plurality of streamers arranged between the support rods in the sailing direction of the ship.
Abstract:
A marine streamer spread for acquiring seismic data, the spread including a streamer having a first portion and a second portion; the first portion including both first pressure sensors and pressure derivative sensors for acquiring the seismic data; and the second portion including second pressure sensors. The first portion imparts ghost diversity to the seismic data by having a variable-depth profile and the pressure derivative sensors impart polarity diversity to the seismic data.
Abstract:
A streamer for seismic prospection comprising directional sensors (20), such as geophones or accelerometers, distributed along the streamer, characterized in that said streamer comprises at least two tilt sensors (30, 40) located in remote positions and in locations distant from the directional sensors (20) and means which determined the effective orientation of each directional sensor (20) by interpolating along the streamer the tilt detected by the two tilt sensors (30, 40).
Abstract:
A seismic detection line includes one or more identified element(s) arranged in a string, and a telemetry link connecting the element(s) along the string to convey seismic data from at least one of the element(s) to a data recorder and identification data to a topology controller. Each of the element(s) includes a respective first identification unit connected to the telemetry link to provide a respective first identifier to the topology controller. A seismic detection system also includes a processor that queries the identified element(s) for their respective identifiers, determines an arrangement of the seismic detection line using the received identifiers, and presents an indication of the determined arrangement. A method of operating a seismic detection line includes transmitting a query along the telemetry link, detecting whether the respective identifier of one of the element(s) was received or not, repeating until termination, and determining and indicating the arrangement.
Abstract:
A stress-relief device is provided, which is configured for being mounted on a geophysical equipment or node connected to at least two cables. The device includes a case configured for surrounding the geophysical equipment or node and for making at least an opening for enabling a connection between each of the at least two cables and the geophysical equipment or node. The device also includes a housing for housing a portion of each of the two cables, the housing being configured for substantially preventing any movement of said portions of the two cables.
Abstract:
An embodiment of the disclosed invention includes a method for attenuating noise during acquisition of marine seismic date. The method includes placing a seismic streamer in a body of water. The seismic streamer includes a streamer body having a length and a channel, a seismic sensor disposed within the channel, and a gel disposed within the channel. The gel has a complex viscosity of at least 50 Pascals and includes a concentration of a polymer between the range of about 5% and about 25% by weight. The method also includes placing a source in the body of water. The seismic streamer and the source are towed through the body of water and the source is fired while being towed through the body of water. Data is collected from the seismic streamer as it is towed through the body of water.
Abstract:
A method for seismic surveying includes positioning a first vessel equipped with first air gun and a first towline at a first selected position and positioning a second vessel equipped with a second air gun and a second towline at a second selected position. The method also includes attaching a transverse tow wire having a paravane fastened at each end to the first towline and the second towline, attaching a streamer cable to the transverse tow wire, and firing at least one of the first air gun and the second air gun and receiving seismic data using the streamer cable.
Abstract:
A technique includes designing a streamer, which includes a cable and seismic sensors based at least in part on a relationship between vibration noise and a bending stiffness of the cable.
Abstract:
A marine seismic streamer comprising a solid, hydrophobic core member that is encased in a hydrophobic streamer skin/casing. The hydrophobic streamer skin may be extruded onto and/or heat welded to the hydrophobic core member. The hydrophobic streamer skin/casing may comprise a thermoplastic polyurethane that includes fluorine and/or silicon moieties, silicon, polydimethylsiloxane or the like. The hydrophobic streamer skin/casing may reduce the drag of the streamer and may provide anti-biofouling properties to the streamer. A hydrophobic paint, coating or polymer may in some instances be disposed on top of the hydrophobic streamer skin/casing.
Abstract:
An anti-biofouling casing for a seismic streamer is described, the anti-biofouling casing comprising a polymer system comprising a hydrophobically-modified base polymer, the hydrophobically-modified base polymer comprising a base polymer having a backbone and a hydrophobically derivatized chain extender coupled to said backbone of said base polymer, wherein the the hydrophobically derivatized chain extender comprises a hydrophobic moiety. The anti-fouling casing comprises a hydrophobic surface to which a layer—such as a coating or a paint—of a material having low surface energy may be coupled to provide an anti-biofouling layer on the seismic streamer.