Abstract: A vibratory casing recovery bottom hole assembly and a method of recovering casing in a wellbore. The vibratory casing recovery bottom hole assembly includes a casing spear, a flow modifier and a dynamic amplification tool. The flow modifier produces cyclic variations in fluid pressure through the assembly at a first frequency and the bottom hole assembly is configured to have a natural or resonant frequency when vibrated to be near or at the first frequency. The dynamic amplification tool induces vibration in the bottom hole assembly while ensuring the dynamic amplification factor of the system is greater than one so as to transmit maximum vibration to the casing at the casing spear. Embodiments of dynamic amplification tools are described.

Abstract: A method of recovering casing in a wellbore using a vibratory casing recovery bottom hole assembly. In a vibratory casing recovery bottom hole assembly having a casing spear, a flow modifier and one or more further elements including a shock sub. The flow modifier produces cyclic variations in fluid flow through the assembly at a first frequency and at least one of the elements is configured to have a natural or resonant frequency when vibrated to be near or at the first frequency. By tuning elements of the bottom hole assembly to be close or at the frequency of the output of the flow modifier, the dynamic amplification factor of the system is maximised and longer lengths of casing can be recovered. A method of recovering casing using the vibratory casing recovery bottom hole assembly is also described. Further embodiments include a casing cutter and a hydraulic jack.

Abstract: A method of recovering casing in a wellbore using a vibratory casing recover), bottom hole assembly. In a vibratory casing recover), bottom hole assembly having a casing spear, a flow modifier and one or more further elements including a shock sub. The flow modifier produces cyclic variations in fluid flow through the assembly at a first frequency and at least one of the elements is configured to have a natural or resonant frequency when vibrated to be near or at the first frequency. By tuning elements of the bottom hole assembly to be close or at the frequency of the output of the flow modifier, the dynamic amplification factor of the system is maximised and longer lengths of casing can be recovered. A method of recovering casing using the vibratory casing recover), bottom hole assembly is also described. Further embodiments include a casing cutter and a hydraulic jack.

Abstract: A vibratory casing recovery bottom hole assembly and a method of recovering casing in a wellbore. The vibratory casing recovery bottom hole assembly includes a casing spear, a flow modifier and a dynamic amplification tool. The flow modifier produces cyclic variations in fluid pressure through the assembly at a first frequency and the bottom hole assembly is configured to have a natural or resonant frequency when vibrated to be near or at the first frequency. The dynamic amplification tool induces vibration in the bottom hole assembly while ensuring the dynamic amplification factor of the system is greater than one so as to transmit maximum vibration to the casing at the casing spear. Embodiments of dynamic amplification tools are described.

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: 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.

Abstract: The present invention provides a steerable hydrofoil. The apparatus includes at least one steerable hydrofoil panel, at least one body part coupled to the at least one steerable hydrofoil panel to allow the at least one steerable hydrofoil panel to rotate about an axis, and at least one actuator for rotating the at least one steerable hydrofoil panel by a selected angle about the axis.

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: A seismic survey system includes a winch having a winch cable coupleable to a source array towable between two deflected lead-ins, a positioning system for determining a current position of the source array and a controller for adjusting the winch to modify the current position of the source array to a desired crossline position. The winches may be attached to the deflected lead-ins or mounted on a tow vessel. The winches exert lateral forces on the source array, derived from the deflected lead-ins, to control the inline position of the source array. A method includes positioning a seismic source array in tow behind a vessel comprises determining a current position of the source array and adjusting a lateral force applied to the source array to move the source array to a desired crossline position. Optionally, by adjusting the gun cable winch, the inline position may be controlled.

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: 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.

Abstract: A method for use in seismic surveying includes determining the shape of a seismic cable during a seismic survey; determining the tension on the seismic cable at a plurality of points along the seismic cable; and predicting a current that will impact the seismic cable from the determined shape and the determined tension. The method may be practiced two-dimensionally in the context of a marine survey employing a towed streamer array or three-dimensionally in the context of laying an array of ocean bottom cables on the seabed. The predicted currents can, in some embodiments, be used to make steering corrections for the seismic cables.

Abstract: A system for adjusting a deflector in a seismic survey comprises a generally upright deflector body and at least one bridle connected to a seismic cable. The bridle includes an upper segment secured to an upper connection point on the deflector body, and a lower segment coupled to a lower connection point on the deflector body. The upper bridle segment, lower bridle segment and deflector body define a geometry between themselves. This geometry is adjustable by at least one actuator so as to control the tilt angle of the deflector body.

Abstract: A seismic survey system includes a winch having a winch cable coupleable to a source array towable between two deflected lead-ins, a positioning system for determining a current position of the source array and a controller for adjusting the winch to modify the current position of the source array to a desired crossline position. The winches may be attached to the deflected lead-ins or mounted on a tow vessel. The winches exert lateral forces on the source array, derived from the deflected lead-ins, to control the inline position of the source array. A method includes positioning a seismic source array in tow behind a vessel comprises determining a current position of the source array and adjusting a lateral force applied to the source array to move the source array to a desired crossline position. Optionally, by adjusting the gun cable winch, the inline position may be controlled.

Abstract: A seismic survey system includes a winch having a winch cable coupleable to a source array towable between two deflected lead-ins, a positioning system for determining a current position of the source array and a controller for adjusting the winch to modify the current position of the source array to a desired crossline position. The winches may be attached to the deflected lead-ins or mounted on a tow vessel. The winches exert lateral forces on the source array, derived from the deflected lead-ins, to control the inline position of the source array. A method includes positioning a seismic source array in tow behind a vessel comprises determining a current position of the source array and adjusting a lateral force applied to the source array to move the source array to a desired crossline position. Optionally, by adjusting the gun cable winch, the inline position may be controlled.

Abstract: A seismic survey system includes a winch having a winch cable coupleable to a source array towable between two deflected lead-ins, a positioning system for determining a current position of the source array and a controller for adjusting the winch to modify the current position of the source array to a desired crossline position. The winches may be attached to the deflected lead-ins or mounted on a tow vessel. The winches exert lateral forces on the source array, derived from the deflected lead-ins, to control the inline position of the source array. A method includes positioning a seismic source array in tow behind a vessel comprises determining a current position of the source array and adjusting a lateral force applied to the source array to move the source array to a desired crossline position. Optionally, by adjusting the gun cable winch, the inline position may be controlled.

Abstract: A system for adjusting a deflector in a seismic survey comprises a generally upright deflector body and at least one bridle connected to a seismic cable. The bridle includes an upper segment secured to an upper connection point on the deflector body, and a lower segment coupled to a lower connection point on the deflector body. The upper bridle segment, lower bridle segment and deflector body define a geometry between themselves.

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.

Abstract: The present invention provides an apparatus and a method for reducing wing-tip vortex energy during seismic exploration. The apparatus includes a vortex concentrator of deployed proximate a tip of a hydrofoil and a vortex reducing device deployed proximate the vortex concentrator.

Abstract: A method for use in seismic surveying includes determining the shape of a seismic cable during a seismic survey; determining the tension on the seismic cable at a plurality of points along the seismic cable; and predicting a current that will impact the seismic cable from the determined shape and the determined tension. The method may be practiced two-dimensionally in the context of a marine survey employing a towed streamer array or three-dimensionally in the context of laying an array of ocean bottom cables on the seabed. The predicted currents can, in some embodiments; be used to make steering corrections for the seismic cables.