Abstract: A seismic source for generating seismic waves under water includes an operating head having an operating chamber, a cushion chamber, and discharge ports, a firing chamber attached to the operating head, the firing chamber configured to hold compressed air to be discharged through the discharge ports, and a shuttle assembly having a shaft located within the operating head and configured to prevent the compressed air in the firing chamber to enter the discharge ports when in a close state, and to allow the compressed air in the firing chamber to be discharged through the discharge ports when in an open state. The shaft of the shuttle assembly which extends in both the operating chamber and the cushion chamber, has a channel having a varying depth.

Abstract: An air gun for generating seismic waves in a marine environment includes a cylindrical body configured to hold compressed air and having plural air ports for releasing the compressed air from inside the cylindrical body, the cylindrical body extending along a longitudinal axis X, and an extension member attached externally to the body and extending along a radial axis R, which is perpendicular to the longitudinal axis X. The extension member promotes ambient water flowing inside an air bubble generated when the compressed air is released outside the body.

Abstract: A seismic source using tuned pulse sources to form an ultra-low frequency (ULF) cluster intended for use in generating seismic energy impulses for marine seismic exploration and more specifically to improved performance by increasing low frequency output to within a range of 1 Hz to 3 Hz to provide greater penetration of the seismic signal through complex overburden such as salt or basalt.

Abstract: A seismic source having two or more operating heads with a firing chamber pressure vessel of compressed air for generating seismic oscillations at low and ultra-low frequencies (ULF) for marine seismic exploration. The multi-headed sound source increases low frequency signal in ranges from below 1 Hz to around 7 Hz to provide greater penetration of the seismic signal through complex overburden such as salt or basalt, improve velocity model building with methods such as Full Wave Inversion, improve the ability to build blocky reservoir models, and improve resolution by reducing side lobes.

Abstract: A section of a streamer for acoustic marine data collection, the section having a carrier for accommodating seismic sensors, wherein the carrier includes, a single body, a first particle motion sensor located on the single body, and a second particle motion sensor being located on the single body, with a 90° angular offset, about a longitudinal axis of the carrier, relative to the first particle motion sensor; and a tilt sensor coupled to the carrier and having a known direction relative to the first and second particle motion sensors so that the tilt sensor determines an angle of tilt of the carrier about a vertical. The first and second particle motion sensors measure a motion related parameter and not a pressure.

Abstract: A low-vibration collar system for vibration mitigation in a device towed in water. The low-vibration collar system includes a clamp attached to a streamer towed underwater by a seismic vessel, the streamer comprising a plurality of sensors to record seismic data; a collar configured to be attached to the clamp; a connecting mechanism located on the collar and configured to attach an ancillary device to the collar; and a vibration mitigation system configured to attenuate an amplitude of a vibration produced by the ancillary device. The vibration interferes with seismic data recorded by seismic sensors located on the streamer.

Abstract: Method and dynamic vibration absorber device for reducing a resonant frequency of a node to which the dynamic vibration absorber device is attached to. The dynamic vibration absorber device includes a housing configured to be attached to the node; an absorber mass located inside the housing; and first and second diaphragms attached to the housing and configured to suspend the absorber mass inside the housing. The dynamic vibration absorber device changes a resonant frequency of the node to two smaller vibration peaks.

Abstract: An apparatus for indicating overstress in an electro-mechanical cable. The apparatus includes an overstress an overstress indicator cable including at least one non-twisted conductor disposed within a section of the electro-mechanical cable, where the non-twisted conductor is adapted to break when tension in the non-twisted conductor is greater than an allowable working load for the electro-mechanical cable.

Abstract: A section of a streamer for acoustic marine data collection, the section comprising a carrier for accommodating seismic sensors, wherein the carrier includes, a single body, a first particle motion sensor located on the single body, and a second particle motion sensor being located on the single body, with a 90° angular offset, about a longitudinal axis of the carrier, relative to the first particle motion sensor; and a tilt sensor coupled to the carrier and having a known direction relative to the first and second particle motion sensors so that the tilt sensor determines an angle of tilt of the carrier about a vertical, wherein the first and second particle motion sensors measure a motion related parameter and not a pressure.

Abstract: A restrictor device is used on a cable to protect the cable from excessive bending. The restrictor device includes two or more restrictor members having a helix shape extending along a longitudinal axis X; and fasteners that connect the two or more restrictor members to each other to form the restrictor device. At least one property of the two or more restrictor members is selected such that a bending portion of the restrictor device moves along the restrictor device when a magnitude of a force applied to the restrictor device changes.

Abstract: Method and apparatus for mitigating vibrations in a device towed in water. The apparatus includes one or more tuned elastic sections having a complex spring rate and adapted to attenuate vibrations in a specified frequency range; and a head end coupler adapted to couple the apparatus for vibration mitigation to a component of an electro-mechanical cable or a tow assembly. One of the one or more tuned elastic sections is coupled to the head end coupler with a high impedance material interface.

Abstract: Method and apparatus for mitigating vibrations in a device towed in water. The apparatus includes one or more tuned elastic sections having a complex spring rate and adapted to attenuate vibrations in a specified frequency range; and a head end coupler adapted to couple the apparatus for vibration mitigation to a component of an electro-mechanical cable or a tow assembly. One of the one or more tuned elastic sections is coupled to the head end coupler with a high impedance material interface.

Abstract: A seismic streamer includes a sensor comprises an axially oriented body including a plurality of axially oriented channels arranged in opposing pairs; a plurality of hydrophones arranged in opposing pairs in the channels; a pair of orthogonally oriented acoustic particle motion sensors; and a tilt sensor adjacent or associated with the particle motion sensors. The streamer has a plurality of hydrophones, as previously described, aligned with a plurality of accelerometers which detect movement of the streamer in the horizontal and vertical directions, all coupled with a tilt sensor, so that the marine seismic system can detect whether a detected seismic signal is a reflection from a geologic structure beneath the streamer or a downward traveling reflection from the air/seawater interface.

Abstract: A seismic streamer includes a sensor comprises an axially oriented body including a plurality of axially oriented channels arranged in opposing pairs; a plurality of hydrophones arranged in opposing pairs in the channels; a pair of orthogonally oriented acoustic particle motion sensors; and a tilt sensor adjacent or associated with the particle motion sensors. The streamer has a plurality of hydrophones, as previously described, aligned with a plurality of accelerometers which detect movement of the streamer in the horizontal and vertical directions, all coupled with a tilt sensor, so that the marine seismic system can detect whether a detected seismic signal is a reflection from a geologic structure beneath the streamer or a downward traveling reflection from the air/seawater interface.

Abstract: Method and apparatus for suppressing cable dynamics in a device towed in water. The apparatus includes at least one section for suppression of motion, wherein the at least one section includes an axial motion suppression section; and the axial motion suppression section comprising equipment for the attenuation of axial vibrations in an electro-mechanical cable. The equipment is configured to produce a digressive stiffness curve.

Abstract: A torque relief system dissipates a torque in a marine cable section to be used for seismic data collection. The system includes a bench having a deadman unit; a tensioning element connected to the deadman unit; a swivel bearing unit connected to the tensioning element and configured to receive a first end of the marine cable section; and at least one bearing unit configured to support the marine cable section with reduced friction so that when the tensioning element tenses the marine cable section, the marine cable section and the first end rotate freely until the torque is dissipated.

Abstract: There is a testing device for testing a sensor. The testing device includes a rotating mechanism; a first rotating plate connected to the rotating mechanism so that the first rotating plate rotates around an orbital axis (Z1); a second plate rotatably attached to the first rotating plate at a rotating point, the second plate having a rotational axis (Z2) offset from the orbital axis (Z1) by a predetermined distance R; and a gripping mechanism attached to the second plate and configured to receive and fix the sensor relative to the second plate. The second plate follows a circular trajectory with constant attitude around the orbital axis (Z1).

Abstract: A method for electrically setting a gap for a piezoelectric pressure sensor. The method includes positioning a piezoelectric flex element on a tray; attaching a voltage source to the piezoelectric flex element of a piezoelectric pressure sensor; applying a voltage from the voltage source to the piezoelectric flex element; curing an adhesive between the piezoelectric flex element and the tray while the piezoelectric flex element is deflected by the voltage; and stopping the voltage from the voltage source to the piezoelectric flex element when the adhesive has been cured.

Abstract: A seismic sensor detects a characteristic of a medium during a seismic survey. The seismic sensor includes a casing; a magnet located inside the casing; a coil assembly located inside the casing, wherein the coil assembly moves relative to the magnet; and a temperature-sensitive device connected to terminals of the coil assembly and configured to improve the damping. The magnet and the coil assembly produce some intrinsic damping and the additional damping introduced by the temperature-sensitive device is selected to counterbalance the temperature-dependent intrinsic damping so that a phase of a recorded seismic signal is compensated for temperature induced magnetic field changes.

Abstract: A switch for a marine seismic sensor. The switch includes a bellows having a closed end, a side portion and an open end, wherein the side portion connects the closed end to the open end, the closed end includes a conductive surface, and the side portion acts as a spring; a base plug that includes first input and first output contacts on a first side and second input and second output contacts on an opposite side; and a plug located in the open end of the bellows and configured to form a chamber, inside which the second input contact and the second output contact are provided. The conductive surface short-circuits the second input contact and the second output contact when a pressure larger than a predetermined pressure (P) acts on the conductive surface.