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:
System and method for controlling an instrumented cable (30) towed in water, such as a marine seismic streamer and/or an instrumented towed cable array (streamer array), to which at least one instrumented cable (30), control devices (10, 20) are arranged to control the individual instrumented cables (30) both in shape and position in relation to other instrumented cables (30) and then counteract cross currents and/or other dynamic forces affecting a towed cable array behind a seismic survey vessel (50). The wings (12, 23) of the control devices (10, 20) are provided with acoustic transmitter/receiver means (14) and electronics for acoustic ranging, and the vessel (50) and one or more tail buoys (60) are provided with acoustic transmitter/receiver means (62) and electronics for acoustic ranging, and is provided with instrumentation for absolute position and velocity.
Abstract:
In various embodiments, a multilayer jacket for a seismic streamer is disclosed. The multilayer jacket comprises an outer layer comprising a water-resistant and wear-resistant material. The multilayer jacket further comprises an inner layer comprising a hydrocarbon impermeable material.
Abstract:
Disclosed herein are various embodiments of a method and apparatus to enhance spatial sampling in all nominally horizontal directions for Dual-Sensor seismic data at the bottom of a body of water such as the ocean. The sensor apparatus on the water bottom is comprised of sensing elements for linear particle motion, for rotational motion, for pressure measurement, for pressure gradients, and for static orientation. Stress and wavefield conditions known at the water bottom allow numerical calculations that yield enhanced spatial sampling of pressure and nominally vertical linear particle motion, up to double the conventional (based on physical sensor locations) Nyquist spatial frequency in two nominally horizontal independent directions. The method and apparatus have a wide range of application in Ocean Bottom Seismic 3D, 4D, and Permanent Reservoir Monitoring surveys, and other marine seismic surveys, in oil and gas exploration and production.
Abstract:
Streamers used in mapping strata beneath a marine body are described, such as in a flexible neutrally buoyant towed array. A connector is used to longitudinally join a first and second streamer section and/or to connect a streamer section to a streamer stabilizer. The connector contains at least one of: (1) means for distributing axial stress over a larger volume or along a longer x-axis length of the streamer relative to the absence of the means for distributing; (2) forming an increasing radius of curvature along the length of the connector as a function of distance from the first leading streamer cable section; and (3) co-moving an inner stress bearing element and an outer wall of the connector preventing intermediate streamer elements, such as a wire bundle from picking up noise related to the movement stress.
Abstract:
A seismic streamer and associated method are provided. The seismic streamer may include a seismic streamer core having a cylindrical configuration. A melt-processable thermoplastic layer may be coupled with the seismic streamer core, the melt-processable thermoplastic layer being extruded to form a first tube. An elastomeric layer may be coupled with the melt-processable thermoplastic layer, the elastomeric layer being extruded to form a second tube.
Abstract:
A marine seismic system having a tow vessel; a first tow member connected to the tow vessel; a second tow member connected to the tow vessel; a first distance member having a first end connected to the first tow member and a second end connected to the second tow member; and a first attachment device connecting the first end to the first tow member, the first attachment member operational between an engaged position securing the first end of the distance member in a fixed position relative to the first tow member and a disengaged position permitting the first attachment device to move along a portion of the first tow member.
Abstract:
Disclosed arc methods and systems for using a rigid-stem assembly comprising a plurality of interconnected rigid stems in a marine survey. An embodiment discloses a geophysical sensor streamer comprising a rigid-stem assembly comprising a plurality of rigid stems that are interconnected and each comprise a stem body defining, one or more interior chambers, wherein a geophysical sensor is incorporated into one or more of the rigid stems.
Abstract:
An acoustic array hose is provided for towing behind a marine vessel. The acoustic array includes acoustic sensors, a hydraulic fill-fluid circumferentially surrounding the acoustic sensors, and an array hose wall of polyurethane with single wall carbon nanotubes embedded therein. The hose wall circumferentially surrounds the hydraulic fill fluid along a length of the array hose. When an electrical current is applied to the towed array, the nanotubes align with the hose wall with the effect of strengthening the hose wall of the towed array.
Abstract:
Performing a geophysical survey beneath a surface obstruction, or around a fixed object or formation. At least some of the example embodiments include: programming a towing pattern into an autonomous underwater vehicle; and towing a sensor streamer under the surface obstruction, or around the fixed object or formation by the autonomous underwater vehicle. In some of the embodiments, the sensor streamer comprises a distributed sensor in the form of an optical fiber. In some of the embodiments, the optical fiber is encapsulated in an outer covering of resilient material, the resilient material exposed to the water during the towing.