A method for seismic processing includes receiving measured seismic data collected by recording seismic waves that propagate through a subterranean domain, simulating synthetic seismic data using a model of the subterranean domain, generating a first time-space panel including the measured seismic data and a second time-space panel including the synthetic seismic data, applying a first moving window to the first time-space panel and a second moving window to the second time-space panel, determining a misfit by comparing the measured seismic data in the first moving window with the synthetic seismic data in the second moving window, and adjusting the model based on the misfit.

A multi-wavefield seismic detection method and system based on construction noise of a shield machine. Multi-wavefield seismic information such as a body wave and a surface wave formed during propagation of a seismic wave generated by excitation in a stratum is obtained by using noise information caused by the construction of a shield machine as a seismic source, a stratum velocity model along a tunnel is constructed through joint inversion, and reflection wave information or the like is used for migration imaging, to eventually implement relatively accurate detection of a geological condition in front of a tunnel face of shield construction.

Logging of data by a downhole tool disposed in a borehole may be affected by tool wave effects. The tool waves appear in the first echo of casing wave arrivals and the amplitudes may be much larger than casing wave arrivals. The estimates of casing wave amplitude are biased due to these tool wave arrivals when using conventional cement-bond logging (CBL) processing. An automated adaptive inversion-based array processing for CBL evaluation using a downhole tool provides an improvement in the calculation of a bonding index.

A multi-wavefield seismic detection method and system based on construction noise of a shield machine. Multi-wavefield seismic information such as a body wave and a surface wave formed during propagation of a seismic wave generated by excitation in a stratum is obtained by using noise information caused by the construction of a shield machine as a seismic source, a stratum velocity model along a tunnel is constructed through joint inversion, and reflection wave information or the like is used for migration imaging, to eventually implement relatively accurate detection of a geological condition in front of a tunnel face of shield construction.

A retrofit valve shutoff device is provided that comprises a coupling key for coupling with an actuator of a shutoff valve on a fluid supply line, an inertial measurement unit for generating one or more signals in response to arrival of seismic waves, a motor for rotating the coupling key and the actuator of the shutoff valve, and a processing unit for receiving the one or more signals from the inertial measurement unit, analyzing the received signals to determine whether to close the shutoff valve, and sending a signal to the motor to rotate the coupling key and the actuator of the shutoff valve to close the shutoff valve based on the analysis of the received signals.

A method and system for estimating a full elastic tensor. The method may comprise taking a measurement for compressional wave sonic data and cross-dipole shear data with a sonic logging tool at a first location as cross-dipole data, processing the compressional wave sonic data to produce a compressional wave slowness (P), and processing the cross-dipole shear data to produce a fast horizontal polarized shear wave slowness (SH) and a slow quazi-vertical shear wave slowness (qSV) as a function of depth. The method may further comprise setting an initial guess for at least five constants of the full elastic tensor for Vertical Transversely Isotropy (VTI) symmetry, determining a modeled slowness surfaces from the full elastic tensor, and comparing the modeled slowness surfaces with measured values of the P, the SH, and the qSV. The method may be performed by a system comprising a sonic logging tool and an information handling system.

Methods and systems for forming a three-dimensional (“3D”) seismic image of a subterranean region of interest is disclosed. The method includes obtaining a seismic dataset a seismic trace for each of a plurality of pairs of one source and one receiver location and obtaining a 3D travel-time cube for each source location and each receiver location. The method further includes dividing the seismic dataset into a plurality of seismic subsets composed of set of source locations, set of receiver locations a seismic trace for each pair of source and receiver location and the 3D travel-time cube for each source for each receiver location. The method still further includes transmitting, to a random-access memory block of a computer processing unit the seismic subset, and forming a seismic partial image based on the seismic subset, and determining the 3D seismic image based on a combination of the seismic partial images.

A vehicle with a LIDAR system, the LIDAR system having an emitter, receivers and a controller. The emitter emitting a Fourier series sum signal with each frequency given a substantially randomized phase. The receivers include a first receiver receiving a portion of the signal proximate to the LIDAR system; and a second receiver receiving a portion of a reflected signal, the reflected signal being a portion of the series sum signal after being reflected off of an object. The controller is coupled to the emitter and the receivers. The controller being configured to de-convolve the portion of the reflected signal received by the second receiver with the portion of the series sum signal received by the first receiver, and to estimate a distance to the object dependent upon an identified time delay between the portion of the reflected signal and the portion of the series sum signal.

A system (100) for monitoring a subterranean structure comprises an array (10) with n acoustic sensors capable of detecting P-waves and/or S-waves from the subterranean structure and a central controller (120) for receiving a signal (X) from the sensors. The system further comprises a lookup table (20) comprising a pre-computed travel time curve (24) expressed as relative arrival times of a signal from a location (L.sub.m) to each of the sensors (1−n); a comparison unit for comparing the received signal (X) with the pre-computed travel time curve (24), and means for raising an alarm if the received signal (X) matches the precomputed travel time curve (24). Preferably, the alarm is raised if a computed semblance value (26, 27) exceeds a predefined threshold. The system may monitor several locations (L.sub.m) in parallel using a fraction of the computer resources and time required by prior art techniques.

A method for borehole measurements may comprise receiving one or more signals from a linear receiver array, computing an arctan of a Hilbert Transform, isolating a first arriving energy, selecting a reference instantaneous phase on a reference receiver, finding the reference instantaneous phase for the linear receiver array, computing a relative travel time shift, combining a reference pick time with a relative time, and determining a travel time. A system for borehole measurements comprise a conveyance, a bottom hole assembly attached to the conveyance, a linear receiver array, wherein the linear receiver array is disposed on the bottom hole assembly, and a computer system connected to the linear receiver array.