Patent classifications
G01V1/189
System and method for phased array sound wave advanced geological exploration for shield tunneling machine
The present invention discloses a system and method for phased array sound wave advanced geological exploration for a shield tunneling machine. The system includes a phased array sound wave emitting and receiving apparatus, a probe automatic telescopic apparatus, an automatic protection and cleaning apparatus, and a signal processing and imaging system. Sonic probes are installed on a side wall of a main spoke, opposite to a rotation direction, of a cutterhead of the shield tunneling machine, on the basis of automatic detection of a telescopic state and a contact state, sonic array probes are enabled to make contact with a tunnel face by a hydraulic push rod, a focus sound wave is emitted by using a phased array emitting technology, and a reflected wave signal with front geological information reflected from the front of the tunnel face is received. A scanning direction of a sound wave beam is controlled and changed continuously through a host system, on the premise of obtaining a suspected abnormal body position, the suspected position is imaged in detail by using a focusing image till scanning of a whole two-dimensional section is completed, then the cutterhead is rotated to change an arrangement direction of an array to continue scanning of a next two-dimensional section, and finally three-dimensional geological exploration in front of the tunnel face is realized.
STREAMER MANUFACTURING
A method of manufacturing a streamer section. The method includes coupling together a plurality of prefabricated harness modules. A harness module includes a plurality of geophysical sensors disposed along a length of the harness module and a sensor node communicatively coupled to the plurality of sensors. A first connector is disposed at a first end of the harness module and a second connector disposed at a second end of the harness module. The first connector is coupled to the sensor node and is configured to couple to a second harness module and receive data from a sensor node in the second harness module. The second connector is coupled to the sensor node and is configured to couple to a third harness module and forward data to a sensor node in the third harness module.
HYBRID SEISMIC DATA ACQUISITION DEVICE AND CORRESPONDING METHODS
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.
Seismic system with ghost and motion rejection
An underwater seismic system for reducing noise due to ghost reflections or motion through the water from seismic signals. The system includes two motion sensors. One sensor has a first response and is sensitive to platform-motion-induced noise as well as to acoustic waves. The other sensor has a different construction that isolates it from the acoustic waves so that its response is mainly to motion noise. The outputs of the two sensor responses are combined to remove the effects of motion noise. When further combined with a hydrophone signal, noise due to ghost reflections is reduced.
Dual axis geophones for pressure/velocity sensing streamers forming a triple component streamer
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.
Attenuation of Axial Vibration Noise in Pressure Sensor Measurements
Methods and apparatus are described for reducing noise in measurements made by one or more pressure sensors disposed in a cable having a generally longitudinal axis. Estimated axial vibration noise at a location along the cable is determined based at least in part on measurements from one or more motion sensors disposed along the cable. The estimated axial vibration noise is subtracted from pressure sensor measurements corresponding to the location. The result is noise-attenuated pressure sensor measurements corresponding to the location.
DOWNHOLE PIEZOELECTRIC ACOUSTIC TRANSDUCER
A sensor system for use in a wellbore is provided that can include a piezoelectric transducer for transmitting an acoustic wave into a fluid medium positioned in the wellbore by repeatedly bending between two positions in response to an actuation signal. The piezoelectric transducer can include at least four piezoelectric layers stacked on top of one another. Each of the four piezoelectric layers can be coupled to an adjacent layer via a bonding material. Each of the four piezoelectric layers can include a piezoelectric material, a top electrode coupled to a top surface of the piezoelectric material, and a bottom electrode coupled to a bottom surface of the piezoelectric material. The sensor system can also include a hydrophone for detecting a reflection or a refraction of the acoustic wave off an object in the wellbore and transmitting an associated signal to a processing device.
Use of vector rotational measurements and vector pressure gradient measurements to enhance spatial sampling of dual-sensor water bottom seismic data
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.
Marine seismic acquisition system
A marine seismic acquisition system includes a frame that includes a central longitudinal axis and members that define orthogonal planes that intersect along the central longitudinal axis; a data interface operatively coupled to the frame; hydrophones operatively coupled to the frame; a buoyancy engine operatively coupled to the frame where the buoyancy engine includes at least one mechanism that controls buoyancy of at least the frame, the hydrophones and the buoyancy engine; and at least one inertial motion sensor operatively coupled to the frame that generates frame orientation data, where the hydrophones, the buoyancy engine and the at least one inertial motion sensor are operatively coupled to the data interface.
NEUTRALLY BUOYANT PARTICLE VELOCITY SENSOR
An autonomous sensor node for undersea seismic surveying is formed as a sphere with density similar to sea water in order to minimize effects of noise. The node is capable of measuring both seismic pressure waves and water-borne particle velocity in three dimensions. The node floats above the seafloor to greatly decrease the impact of shear wave noise contamination generated by seabed waves. The node is attached to an anchor resting on the seabed by a tether. The tether is configured to prevent transfer of any tensile forces caused by shear waves in the seabed stratum from the anchor to the node. The tether may have a varying density along its length to entirely attenuate any force transfer from the seafloor.