The present invention relates to a vector sensor for measuring particle movement in a medium. The vector sensor comprises a magnetic body that is held at a certain distance from a magnetometer in such a way that the magnetic body can move in time with a passing particle movement, wherein the magnetometer is arranged to detect the oscillations in the magnetic field that the movements in the medium produce.

This invention provides a system apparatus and method for ship-towed deployment of a non-linear volumetric array of hydrophones, allowing line-intersect or line-transect sampling of marine mammal populations through passive acoustic monitoring, enabling unambiguous real-time three-dimensional localization of single sounds received through a low-cost, modular, robust, stable, small, light, neutrally to slightly negatively buoyant volumetric array having low self-noise and low flow noise, that avoids putting high tension on the tow cable and that is compatible with standard hydrophones, instrumentation, cabling, and analytical software.

A hydrophone array tool as described herein is configured to locate leakages throughout a borehole with improved accuracy using acoustic beamforming techniques with acoustic velocity estimation. An acoustic beamforming processor generates an initial beamforming map and corresponding initial estimated leakage location using acoustic measurements throughout the borehole. The acoustic beamforming processor generates additional beamforming maps at the initial estimated leakage location, each additional beamforming map corresponding to an acoustic velocity within a range of anticipated acoustic velocities. An acoustic velocity estimator determines an acoustic velocity corresponding to a beamforming map with spatial statistics that indicate a most prominent leakage location. The acoustic beamforming processor updates the leakage location according to this beamforming map for improved accuracy.

It is proposed a seismic data acquisition device (400) intended to be placed on an ocean bottom floor, comprising a polymeric casing (412) defining a chamber that houses at least art of a data acquisition system (440, 444, 445); and a metallic device (414) in which the polymeric casing (412) is trapped, the metallic device (414) comprising two metallic beams (4141, 4142) that extend on opposite sides of the polymeric casing (412).

It is also proposed a method for assembling such a device and a corresponding method for seabed seismic data acquisition.

The present disclosure belongs to the technical field of an ultrasonic sound field measuring system, and relates to a manual acoustic axis aligning method for an ultrasonic sound field measuring system. The method comprises: obtaining an intersection between a current acoustic axis and a plane by scanning two detection planes, and calculating an inclination angle of the current acoustic axis; judging whether the inclination angle is less than an adjustment threshold. The method does not depend on the specific mechanical implementation of adjusting an acoustic axis angle. The iterative algorithm combined with geometric information can converge quickly. The criterion of intersection between the acoustic axis and the plane used is not limited to the amplitude criterion, and other criteria can be introduced by increasing the distance between two planes to increase the robustness of measuring the acoustic axis angle.

A packed sensor line array system includes sensors mounted outboard of cable packs wrapped around a central mandrel. The system may have multiple rows (layers) of the sensors and cable packs, surrounded by a cannister. Cable retainers may be used to retain cable ends near sensors, to keep the cable ends out of the way of subsequent winding operations. The winding may be done in situ, with the mandrel mounted to a rotatable chuck that is rotated to wind the individual cable packs sequentially around the mandrel, with positioning of the sensors outboard of the windings occurring between the winding operations. A positionable indexing tool may be coupled to and moved along the mandrel, to define a space along the mandrel for each cable pack winding.

This invention provides a system apparatus and method for ship-towed deployment of a non-linear volumetric array of hydrophones, allowing line-intersect or line-transect sampling of marine mammal populations through passive acoustic monitoring, enabling unambiguous real-time three-dimensional localization of single sounds received through a low-cost, modular, robust, stable, small, light, neutrally to slightly negatively buoyant volumetric array having low self-noise and low flow noise, that avoids putting high tension on the tow cable and that is compatible with standard hydrophones, instrumentation, cabling, and analytical software.

The disclosure generally relates to a method, apparatus and system to deploy aquatic sensors to obtain oceanographic data. In an exemplary embodiment, a free-floating or untethered sensor receives signals from different transmitters. The signals may be configured to travel through air and/or water. The sensor records each signals' time of arrival and determines its location in relationship to known transmitters based on the signal travel time. The position of each sensor may be determined by triangulation to several devices whose positions are known. The distances from the sensor in question to each device is measured by means of time-of-flight measurements for a wireless signal from the sensor to each known-position device. Other methods such as trilateration or dead-reckoning may also be used. The sensor may additionally collect and record oceanographic or other environmental data.

This disclosure is related to hydrophones, for example hydrophones that may be used in marine seismic surveying, permanent reservoir monitoring, downhole acoustic monitoring in a wellbore, and/or various other applications. Some embodiments of a hydrophone according to this disclosure are constructed such that a longitudinal stiffness of the hydrophone is greater than a circumferential stiffness of the hydrophone. In some embodiments, however, the longitudinal stiffness may be somewhat less than the circumferential stiffness. For example, the longitudinal stiffness may be greater than one half the circumferential stiffness in some cases.

A hydrophone free from internal leads and further including a stabilizing jacket is described. The hydrophone uses the metallic end caps of the stabilizing jacket to complete the circuit thereby eliminating the need for internal leads. Further, the stabilizing jacket results in a hydrophone configuration that can withstand harsher conditions while nonetheless providing excellent detection capabilities.