G01V1/186

Solid-state hydrophone with shielding

A solid-state hydrophone may include a piezoelectric rod positioned between at least two electrodes. The piezoelectric rod may be disposed within a metallic housing to shield the piezoelectric rod and its connections from acoustic and electromagnetic waves. The piezoelectric rod and the electrodes may be potted in the mechanical housing using a potting material that may be positioned adjacent to the piezoelectric rod. At least a layer of the potting material may be positioned between the piezoelectric rod and the metallic housing to physically separate the piezoelectric rod from the metallic housing.

DETERMINING A SEISMIC QUALITY FACTOR FOR SUBSURFACE FORMATIONS FOR MARINE VERTICAL SEISMIC PROFILES

A seismic attenuation quality factor Q is determined for seismic signals at intervals of subsurface formations between a seismic source at a marine level surface and one or more receivers of a well. Hydrophone and geophone data are obtained. A reference trace is generated from the hydrophone and geophone data. Vertical seismic profile (VSP) traces are received. First break picking of the VSP traces is performed. VSP data representing particle motion measured by a receiver of the well are generated. The reference trace is injected into the VSP data. A ratio of spectral amplitudes of a direct arrival event of the VSP data and the reference trace is determined. From the ratio, a quality factor Q is generated representing a time and depth compensated attenuation value of seismic signals between the seismic source at the marine level surface and the first receiver.

Underwater acoustic test system and method

The underwater acoustic test system comprises an underwater acoustic transmitting unit, an underwater acoustic parabolic reflector, an underwater acoustic receiving unit, an orientation control system, and a computer measurement and control system. The underwater acoustic transmitting unit comprises an underwater acoustic signal generator and a transmitting transducer. The underwater acoustic parabolic reflector comprises a central main reflecting area and an edge diffraction processing area, wherein the central main reflecting area is configured for reflecting acoustic wave signals, and the edge diffraction processing area is configured for reducing the influence of the underwater acoustic parabolic reflector on a test area. The underwater acoustic receiving unit comprises a receiving transducer and an underwater acoustic signal receiver. The orientation control system comprises a traveling crane and a test turntable.

METHOD AND APPARATUS FOR IMPLEMENTING A HIGH-RESOLUTION SEISMIC PSEUDO-REFLECTIVITY IMAGE
20230103668 · 2023-04-06 · ·

A method for generating a high-resolution pseudo-reflectivity image of a subsurface region includes receiving seismic data associated with a subsurface region and captured by one or more seismic receivers, constructing a velocity model of the subsurface region based on the received seismic data, performing a seismic migration of the received seismic data based on the constructed velocity model to obtain migrated seismic data, computing polarized normal vectors associated with one or more subsurface reflectors of the subsurface region based on the migrated seismic data, and generating a pseudo-reflectivity image of the subsurface region based on both the computed polarized normal vectors.

Methods for locating underwater objects by sensing pressure waves

An acoustic vector sensor has an array of sensors to detect at least the bearing of a target. The acoustic vector sensor or hydrophone with sensor array avoids the need to deploy multiple hydrophones each with a single sensor. The array of sensor signals can be processed using any one of a number of methods.

Submerged buoy data acquisition system

The present invention discloses a new submerged buoy data acquisition system, including a battery compartment, a main control processor, a GPS receiver, a gigabit Ethernet interface module, and a plurality of data acquisition boards, where the GPS receiver is connected to the main control processor, and the main control processor is connected to a host computer by using the gigabit Ethernet interface module; the data acquisition board includes a hydrophone sensor, a front-end drive circuit, an AD conversion circuit, a clock module, a DA conversion circuit, an FPGA, an ARM processor, and a storage module; the hydrophone sensor is connected to the AD conversion circuit by using the front-end drive circuit, the AD conversion circuit is connected to the FPGA, the FPGA is connected to the ARM processor, the storage module is connected to the ARM processor, the DA conversion circuit is connected to the FPGA and the clock module, the clock module is connected to the FPGA, and the ARM processor is connected to the main control processor. The present invention improves acquisition performance of the submerged buoy data acquisition system, and implements synchronous acquisition and control of the entire system.

Seismic Data Acquisition with Extended Dynamic Range
20230194742 · 2023-06-22 · ·

A marine seismic data acquisition system may include first and second containers deployable in a body of water. The first container includes a first seismic data acquisition channel capable of transducing seismic energy in the body of water having a first maximum amplitude, and the second contain includes a second seismic data acquisition channel capable of transducing seismic energy in the body of water having a second maximum amplitude. The first seismic data acquisition channel is associated with at least a first seismic sensor, and the second seismic data acquisition channel is associated with at least a second seismic sensor. The second sensor corresponds to a same sensor type as the first seismic sensor, and the first maximum amplitude is higher than the second maximum amplitude.

Interleaf packing and deployment system

A packing module includes a volumetrically efficient structure for separately retaining sensors and a cable of a sensor array. The packing module includes a tray that supports the sensors and a retaining leaf arrangement that extends outwardly from the tray to retain the cable on the tray. The retaining leaf arrangement includes a plurality of nested leaves that are spaced relative to each other. Packing the module includes placing the sensors separately and in succession on the tray and inserting a portion of the cable in the retaining leaf arrangement in between each placing of a sensor. The placement of a sensor and insertion of a portion of the cable occurs alternately until the entire sensor array is accommodated. Deployment of the sensor array may occur by alternately removing a sensor and a portion of the cable until the sensor array is displaced from the module.

Buoy based marine seismic survey system and method
09835750 · 2017-12-05 · ·

A seismic survey system for recording seismic data underwater in the presence of underwater currents. The system includes first plural buoys configured to descend in water at a predetermined depth (H1) and each having a seismic receiver for recording the seismic data; a first vessel configured to launch the first plural buoys along a first line; and a second vessel configured to recover the first plural buoys at a second line, wherein there is a predetermined distance between the first and second lines. The first plural buoys are configured to travel underwater, at substantially the first predetermined depth (H1), from the first line to the second line, due exclusively to the underwater currents.

Low frequency emission and recording for seismic data acquisition
09835745 · 2017-12-05 · ·

Presented are methods and systems for collecting marine seismic data. The collected seismic data can be low frequency (e.g., less than 10 Hz) or it can be a full seismic bandwidth (1-200 Hz) depending on if the low frequency tuned sources and tuned receivers are combined with conventional sources and receivers. The low frequency sources can be towed or they can be autonomous and positioned in the survey area by tether, drifting or self-propelled. The tuned low frequency receivers are towed at a depth greater than conventional receivers and the sources can be fired independently or simultaneously.