An internal structure detection system includes: two kinds of sensors with different operating principles for receiving reflected waves of vibration applied to an inspection target in an investigation area; and a processing apparatus that detects an internal structure of the inspection target by using the sensor data received by the two kinds of sensors. The two kinds of sensors are deployed in the investigation area with different densities, in a distributed manner.

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.

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.

The present invention provides a technique to separate compressional seismic waves from shear seismic waves and to determine their direction of propagation to enhance the seismic monitoring oil and gas reservoirs and the seismic monitoring of hydrofracturing in oil and gas wells. The invention utilizes various combinations of multi-component linear seismic sensors, multi-component rotational seismic sensors, and pressure sensors. Sensors are jointly deployed in arrays of shallow monitoring wells to avoid the complicating effects of the free surface of the earth. The emplacement of sensors in the shallow monitoring wells may be permanent. The method has a wide range of application in oil and gas exploration and production. This abstract is not intended to be used to interpret or limit the claims of this invention.

Methods, systems, and computer-readable medium to perform operations for suppressing seafloor geophone seismic data noise. A computing system applies a vertical geophone de-noise process to enhance a compressional wave signal that is free from (independent of) shear energy leakage. This enhances the signal to noise (S/N) ratio of the vertical geophone component and concurrently make the vertical geophone component consistent with a hydrophone component.

Systems and methods of near surface imaging and hazard detection with increased receiver spacing are provided. The system includes: a first string of one or more acoustic sources, a second string of one or more acoustic sources opposite the first string, a first one or more hydrophones mounted within a predetermined distance of the first string, and a second one or more hydrophones mounted within the predetermined distance of the second string. The first one or more hydrophones records an acoustic shot generated from the first string. The second one or more hydrophones records the acoustic shot and acoustic reflections corresponding to the acoustic shot. The system generates an image from the recorded acoustic shot and the acoustic reflections.

Systems and methods of placing wells in a hydrocarbon field based on seismic attributes and quality indicators associated with a subterranean formation of the hydrocarbon field can include receiving seismic attributes representing the subterranean formation and seismic data quality indicators. A cutoff is generated for each seismic attribute and seismic data quality indicator. A weight is assigned to each seismic attribute and seismic data quality indicator. The weighted seismic attributes and data quality indicators are aggregated for each location in the hydrocarbon field. A risk ranking is assigned based on the weighted seismic attributes and data quality indicators associated with each location in the hydrocarbon field based on the cutoffs. A map is generated with each location on the surface of the subterranean formation color-coded based on its assigned risk ranking.

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.

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.

Systems and methods of placing wells in a hydrocarbon field based on seismic attributes and quality indicators associated with a subterranean formation of the hydrocarbon field can include receiving seismic attributes representing the subterranean formation and seismic data quality indicators. A cutoff is generated for each seismic attribute and seismic data quality indicator. A weight is assigned to each seismic attribute and seismic data quality indicator. The weighted seismic attributes and data quality indicators are aggregated for each location in the hydrocarbon field. A risk ranking is assigned based on the weighted seismic attributes and data quality indicators associated with each location in the hydrocarbon field based on the cutoffs. A map is generated with each location on the surface of the subterranean formation color-coded based on its assigned risk ranking.