Abstract: Embodiments herein include a fairing for a marine seismic array system that includes a foil having a leading edge and a trailing edge and defining a chord length and a span length, a first interior conduit oriented along the span length aft of the leading edge, and a second interior conduit oriented along the span length forward of the trailing edge. The conduits are separated by a distance. A first cable having a first length extends within the first conduit and a second cable having a second length extends within the second conduit, and the fairing can rotate about the first cable within the first conduit.

Abstract: An automatic water sampler is disclosed. The automatic water sampler of the present invention comprises: a driving unit operated according to the pressure measured by a pressure sensor; a driving magnet approaching a driven magnet according to the operation of the driving unit; and a first wire unlocked by a control rod according to the movement of the driven magnet. The present invention can provide an automatic water sampler, which improves inaccuracy due to conventional interference of an ocean current, flow velocity, and the like, and manual water sampling by depth by automatically sampling water at the correct depth recognized through a pressure sensor, thereby enabling reliability and accuracy of a sample to be ensured and sampling expenses to be remarkably reduced.

Abstract: Disclosed are apparatus and methods for determining characteristics of a target region which is embedded in background material below a body of water. In accordance with one embodiment, a resistivity background is determined. In addition, characteristics of an electric dipole due to the target region are determined. A resistance for the target region is then computed using the characteristics of the electric dipole and the resistivity background. Other embodiments, aspects and features are also disclosed.

Abstract: A disclosed direct velocity seismic sensor includes a housing, a proof mass suspended in the housing by a resilient component, and a motion dampener that damps oscillation of the proof mass to a degree that displacement of the proof mass relative to the housing is substantially linearly proportional to a rate of change of seismic displacements of the housing over a frequency range of interest. A described method for constructing a seismic sensor includes using a calculated resonant frequency to determine a damping factor that causes the displacement of the proof mass to be substantially proportional to the rate of change of seismic displacement of the housing. One illustrative disclosed system includes an optical velocity sensor and a detector where a light beam produced by the velocity sensor and a reference beam interfere at the detector, and the detector produces a signal indicative of a velocity experienced by the velocity sensor.

Abstract: Technologies are provided for underwater measurements. A system includes an underwater vessels including: a plurality of sensors disposed thereon for measuring underwater properties; and a programmable controller configured to selectively activate the plurality of sensors based at least in part on underwater pressure. A user may program at what pressure ranges certain sensors are activated to measure selected properties, and may also program the ascent/descent rate of the underwater vessel, which is correlated with the underwater pressure.

Abstract: Method for determining the thickness of an upper layer of a fluid mass comprising at least this upper layer and a lower layer lying thereunder, such as a waterway with a navigable upper layer and a viscous mud layer located thereunder, wherein the viscosity of the fluid of the lower layer is greater than the viscosity of the fluid of the upper layer, wherein a body freely movable in the fluid mass is moved through the fluid mass at a velocity such that the body enters a state of equilibrium substantially at the interface between the lower and upper layer; the depth position of the body is determined at successive points in order to know the thickness of the upper layer at these points; and the resistivity of the fluid in the vicinity of the body is measured at successive points.

Abstract: A method for processing seismic data. The method may include (1) receiving seismic data acquired by an ith seismic sensor of a plurality of seismic sensors and (2) determining an ith value to represent an ith power spectral density curve that corresponds to the seismic data. The method may then repeat steps (1)-(2) for each seismic sensor. The method may then include generating an expected value curve based on the ith value for each power spectral density curve. The method may then compare each ith value to the expected value curve and identify invalid seismic sensors based on the comparison. After identifying the invalid seismic sensors, the method may process the seismic data without seismic data acquired by the invalid seismic sensors to determine one or more locations of hydrocarbon deposits in subterranean geological formations.

Abstract: A float device includes a drive motor provided inside a float hull, a plunger reciprocating along with rotation of the drive motor, an internal oil reservoir for housing an hydraulic oil therein, an externally-opened cylinder attached to the float hull, a buoyant force adjustment piston reciprocating in the cylinder along with exit/entry of the hydraulic oil, and a three-way valve having a first connection port connected to the plunger, a second connection port connected to the internal oil reservoir, and a third connection per connected to the cylinder, for switching the flow between the first connection port and the second connection ports and the flow between the first connection port and the third connection port.

Abstract: A device for disposing an antenna dipole arranged to be submerged in a water mass is described. A first electrode is placed, in an operative position, approximately vertically above and at a distance from a second electrode. A mast is pivotally secured, at a portion distant from, in the operative position, a lower end portion, to a stand. The first electrode is arranged near, in or on an upper end portion of the mast. The second electrode is arranged near, in or on the lower end portion of the mast. The mast and/or stand includes means which are arranged to keep the mast in a prescribed position. The mast and stand are formed substantially of non-magnetic materials.

Abstract: Disclosed are methods and systems for controlling depth profiles of marine geophysical sensor streamers as they are towed in a body of water. An embodiment discloses a method for marine geophysical surveying, the method comprising: towing a geophysical sensor streamer in a body of water having a surface and a floor, the geophysical sensor streamer being coupled to a survey vessel by a lead-in cable, the lead-in cable having a length that extends from the survey vessel; adjusting the length of the lead-in cable to cause a forward end of the geophysical sensor streamer to follow a depth profile; and deflecting the geophysical sensor streamer in the vertical plane at one or more spaced apart locations.

Abstract: An underwater sensor device comprises a submersible housing including one or more housing components, one or more sensors for monitoring and collecting water characteristics, a controller for controlling operations of the one or more sensors and an graphical user interface mounted to the housing that displays the water environmental data. The housing defines a channel that extends through one of the housing components, and at least one of the sensors is mounted to the housing and extends into the channel. The controller is disposed within the housing and is operatively connected to the one or more sensors.

Abstract: A method and system for detecting the location of an air/sea interface on an Instrumented Tow Cable (ITC) when distributed temperature measurements are provided. The air/sea interface is determined by estimating the variance of observed temperature in the proximity of each measurement cell. The method and system described herein uses a sliding variance across the entire cable length. The variance of the cell or cells in the area of the interface has been found to be large compared to other cells. Accordingly, the location of the air/sea interface is determined based on the location of the peak variance. The location of the air/sea interface is used in determining the catenary of the ITC.

Abstract: A method of processing marine magnetic data is disclosed which comprises towing first and second magnetometers M1 and M2 behind a ship (10). Raw magnetic gradient data is obtained from the sensors and the trend of the gradient of the ship bias detected by the sensors determined. The method includes subtracting the trend from the raw magnetic gradient data to obtain corrected gradient data, and processing the corrected gradient data to provide a data output.

Abstract: The present application provides a system, method and apparatus for measuring at least one physical and/or chemical variable at a plurality of different locations within a body of water. The method includes the steps of: providing dynamic measurement means configured to measure the at least one physical and/or chemical variable; towing said measurement means in said body of water at a predetermined depth, and simultaneously taking measurements of least one physical and/or chemical variable, at least periodically, and generating measurement data; and determining the location of the measurement means while taking said measurements of the at least one physical and/or chemical variable and generating corresponding location data. A method for mapping at least one physical and/or chemical variable for a body of water is also disclosed.

Abstract: A method is presented for determining inner and outer boundary layer length scales from a succession of drag measurements of a cylindrical body in order to estimate flow noise and for computational modeling of the dynamics of towed arrays in a fluid medium. A succession of measurements of the total drag on a cylinder under tow at uniform known conditions (flow speed, fluid density, fluid viscosity, cylindrical body geometry) is taken. After each measurement, the cylinder is truncated by a fixed amount, and the process is repeated for the length of the cylinder. The measurements provide a spatially and temporally averaged measure of the mean wall shear stress and momentum thickness, from which the inner and outer length scales can be determined. The inner and outer boundary layer length scales may then be used for estimation of flow noise on towed cylindrical bodies and arrays.

Abstract: An extended optical sensor comprises a plurality of equally spaced intensity-based point sensors connected in parallel such that the optical path lengths are the same within the extended sensor enclosure. The input to the extended sensor is a single optical fiber as is the output.

Abstract: An acoustic warning assembly capable of being launched from an underwater vehicle while being underwater. The acoustic warning assembly includes an acoustosensitive member for collecting above-surface acoustic signals. The acoustic warning assembly also includes a carrier member launchable from the underwater vehicle, the carrier member is designed to carry the acoustosensitive member above-surface. The acoustic warning assembly also includes a communication medium for communicating between the acoustosensitive member and the underwater vehicle, for transmitting the above-surface acoustic signals collected by the acoustosensitive member to the underwater vehicle.

Abstract: Apparatus for studying the variations in hydrodynamic pressure for correlation with fish movement towards and away from zones of danger comprises a hollow winged section having mounted on the surface thereof, piezoelectric sensors, and an accelerometer mounted within the apparatus, for generating electrical signals that are processed and interpreted by remote electronic means.