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Signal analysis and/or correction

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367 - Communications, electrical: acoustic wave systems and devices

367014000 - SEISMIC PROSPECTING

367037000 - Land-reflection type

Patent class list (only not empty are listed)

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Class / Patent application numberDescriptionNumber of patent applications / Date published
367050000 Timing correction 53
367043000 Filters 49
367056000 Particular source-receiver array 23
367041000 Transmitted correlation 17
367040000 Received correlation 13
367047000 Amplitude 12
367049000 Frequency 9
367059000 Compositing system 8
367058000 By receiver pattern arrangement 2
20120026834OBTAINING A RESPONSE BASED ON DIFFERENCING OF OUTPUTS OF SENSORS - A sensor assembly has first sensors spaced apart along a first direction, and second sensors oriented in a second direction generally orthogonal to the first direction. Differencing of outputs of the first sensors is performed, and differencing of outputs of the second sensors is performed. A signal output is produced by combining the differenced outputs of the first sensors and the differenced outputs of the second sensors, where the signal output represents a seismic response of a subterranean structure.02-02-2012
20110249530ARRANGING SENSOR ASSEMBLIES FOR SEISMIC SURVEYING - To perform seismic surveying, a plurality of sensor assemblies are provided, where each of multiple ones of the plurality of sensor assemblies has a seismic sensor and a divergence sensor, and where the divergence sensor is used to measure noise. In addition, the plurality of sensor assemblies are arranged in a layout designed to acquire seismic signals in a target sampling pattern, where the layout is independent of provision of sensor assemblies for noise acquisition.10-13-2011
367042000 Standard correlation 1
20100302905METHOD FOR MONITORING A SUBSOIL ZONE, PARTICULARLY DURING SIMULATED FRACTURING OPERATIONS - A method and device for monitoring a subsoil zone, wherein a plurality of receivers are arranged on a surface of the soil or near said surface, straight above a geological zone to be monitored, comprising the following steps: generating a set of reference seismic data; recording seismic data by means of said receivers; correlating the seismic data recorded with the reference seismic data; comparing each trace of the correlated data, with correlated traces located in a vicinity of said trace, in order to evaluate a similarity of each correlated trace with the adjacent correlated traces; and, detecting a microseismic event occurring in the subsoil zone by analysing said similarity. The method and device enables real-time monitoring.12-02-2010
Entries
DocumentTitleDate
20100195437VELOCITY MODEL FOR WELL TIME-DEPTH CONVERSION - Systems and methods create a velocity model for well time-depth conversion. In one implementation, a system optimizes a time-depth relationship applied to data points from a single well to estimate coefficients for a velocity function that models the data points. The system optimizes by reducing the influence of outlier data points, for example, by weighting each data point to decrease the influence of those far from the velocity function. The system also reduces the influence of top and bottom horizons of geological layers by applying data driven techniques that estimate the velocity function without undue dependence on the boundary conditions. The system can optimize estimation of a rate of increase in velocity to enable the velocity function to go through a data point on each top horizon. The system may also estimate each base horizon from trends in the data points and adjust the velocity function to go through a data point on each base horizon.08-05-2010
20100008187METHOD OF SEISMIC SURVEYING - A method enables the time required to complete a seismic survey and the noises recorded in the seismic data to be reduced. One aspect of the method includes actuating a first vibrator group to start a first sweep at time T01-14-2010
20100157731AUTOMATIC DISPERSION EXTRACTION OF MULTIPLE TIME OVERLAPPED ACOUSTIC SIGNALS - Slowness dispersion characteristics of multiple possibly interfering signals in broadband acoustic waves as received by an array of two or more sensors are extracted without using a physical model. The problem of dispersion extraction is mapped to the problem of reconstructing signals having a sparse representation in an appropriately chosen over-complete dictionary of basis elements. A sparsity penalized signal reconstruction algorithm is described where the sparsity constraints are implemented by imposing a l06-24-2010
201001186504D SEISMIC SIGNAL ANALYSIS - Methods of seismic data collection are described that reduce the amount of data required, reduce noise in the data collected and collect more data in areas where data collection is required. This results in a dramatic reduction of datasets required and improves noise reduction in data collected. By reducing the amount of data collected and increasing the noise reduction, a more accurate seismic survey is conducted at a dramatically reduced cost.05-13-2010
20090154291Attenuating Noise in Seismic Data - The technologies described herein include systems and methods for reducing noise in seismic data. More specifically, implementations may determine an amount of over-sampling for a frequency range of seismic data. Then, implementations may determine frequency bands based on the over-sampling. For each frequency band minimum-noise seismograms may be selected from consecutively occurring blocks of seismograms, and the remaining seismograms within each block may be discarded. The minimum-noise seismograms may then be used to reconstruct the discarded seismograms. The reconstructed seismograms may contain less noise than the original seismograms and, consequently, the seismic data may contain less noise.06-18-2009
20130070562Method and System for Passive Electroseismic Surveying - A method of passive surveying comprises generating one or more detected signals by passively detecting a signal generated within a subsurface earth formation due to a seismoelectric response or an electroseismic response in at least one porous subsurface earth formation containing at least one fluid, and processing the one or more detected signals to determine at least one property of the subsurface earth formation.03-21-2013
20090092007IDENTIFYING AN INTERNAL MULTIPLE GENERATOR IN A SUBTERRANEAN STRUCTURE - A technique is provided for identifying an internal multiple generator in a subterranean structure. The technique includes injecting wavefields at different levels in the subterranean structure, where the different levels are proximate a predicted location of the internal multiple generator. Wavefields induced by the injected wavefields are recorded and the effect of the internal multiple generator based on the recorded wavefields is determined.04-09-2009
20100091611NEAR-SURFACE GEOMORPHOLOGICAL CHARACTERIZATION BASED ON REMOTE SENSING DATA - A technique includes receiving first data belonging to a first type of remote sensing data for a region of interest and receiving second data belonging to a different second type of remote sensing data for the region of interest. The technique includes determining at least one geomorphological feature of the region of interest based at least in part on the first and second data.04-15-2010
20110013482Variable Timing ZENSEIS - Seismic systems and methods are provided to collect variable seismic data, for coordinating source energy and receiver data as well as using both to obtain high resolution seismic data.01-20-2011
20090238040METHOD FOR IMAGING THE EARTH'S SUBSURFACE USING PASSIVE SEISMIC SENSING - A method of imaging the Earth's subsurface using passive seismic emissions includes detecting seismic signals originating from within the Earth's subsurface over a selected time period using an array of seismic sensors deployed proximate the Earth's surface. Hypocenters of seismic events in the subsurface are determined from the detected signals. Seismic signals detected at selected ones of the seismic sensors are cross-correlated to signals detected at other selected ones of the seismic sensors. The cross-correlated signals are processed to obtain a reflectivity series at a geodetic position of the selected one of the seismic sensors. A spatial distribution of at least one seismic property in the subsurface is determined using the determined hypocenters and the reflectivity series.09-24-2009
20090052278GENERATING SWEEP SEQUENCES - A technique includes generating one or more sweep sequences for one or more seismic vibrators for a seismic survey and evaluating a cost for the sequence(s). The technique includes perturbing the sequence(s) and continuing the evaluation and perturbing until the cost is within a limit or a maximum number of perturbations is reached.02-26-2009
20120063263METHODS AND SYSTEMS FOR SEISMIC SIGNAL DETECTION - Methods and systems utilizing seismic sensors configured or designed for use in seismic signal detection. The seismic sensors output displacement signals of a displacement sensor superimposed on velocity signals generated by a moving coil of the seismic sensors.03-15-2012
20110292764Bayesian DHI for Seismic Data - A method of locating subsurface hydrocarbon reservoirs includes acquiring seismic data, extracting seismic data attributes from the seismic data, calculating exemplar data group probability density function values using distribution values associated with the seismic attributes and applying Bayesian inversion to determine the likelihood of subsurface hydrocarbons.12-01-2011
20110085416SYSTEM AND METHOD FOR DETERMINING A FREQUENCY SWEEP FOR SEISMIC ANALYSIS - A sweep generator is employed to generate a sweep to be used by a seismic vibrator device for generating a desired target output spectrum, wherein the frequency sweep is designed so as to comply with one or more constraints imposed by the seismic vibrator device and/or imposed by the environment in which the device is to be used. In one embodiment, a sweep generator determines a sweep for achieving a desired target output spectrum by a given seismic vibrator device in compliance with at least a pump flow constraint imposed by the seismic vibrator device. In another embodiment, a sweep generator determines a sweep for achieving a desired target output spectrum by a given seismic vibrator device in compliance with all of multiple operational constraints of the seismic vibrator device, such as both mass displacement and pump flow constraints. Environmental constraints may also be accounted for in certain embodiments.04-14-2011
20090207693Seismic Location and Communication System - A method and system for determining the location of miners trapped in an underground mine that includes recording a reference seismic signature for each of a plurality of underground base stations in the mine in advance of an emergency. The reference seismic signatures are created by generating first a seismic signal with a high signal-to-noise ratio at each base station, monitoring the signal with a permanent array of surface seismic sensors, and recording each unique signature on a central computer. In the event of an emergency, trapped miners can generate a second seismic signal at any of the underground base stations which can be easily identified with the central computer by using the pre-recorded reference seismic signature to overcome a weak signal-to-noise ratio.08-20-2009
20110286305TIME REVERSE IMAGING OPERATORS FOR SOURCE LOCATION - A method and system for processing synchronous array seismic data includes acquiring synchronous passive seismic data from a plurality of sensors to obtain synchronized array measurements. A reverse-time data propagation process is applied to the synchronized array measurements to obtain a plurality of dynamic particle parameters associated with subsurface locations. Imaging conditions are applied to the dynamic particle parameters to obtain image values associated with subsurface energy source locations.11-24-2011
20080232193Methods for Noise Removal and/or Attenuation from Seismic Data by Wavelet Selection - Seismic data traces contain noises that may exist in the form of wavelets and be represented by wavelets. A method is established for removing or attenuating the noises in the seismic data traces by removing the wavelets or representing wavelets of noises in the seismic data traces. The method involves three steps. (1) Decomposition of each seismic data trace into a set of time dependent wavelets of different shapes. The obtained wavelets can be named with their dominant frequency or other characteristics of the wavelets. (2) Proper selection of the wavelets to form a new set of wavelets that contains mostly signal wavelets and rejects the wavelets of noises and representing wavelets of noises as mush as possible. This step can also be described as to remove the wavelets of noises and representing wavelets of noises from the obtained set of wavelets from step one and form a new set of wavelets. (3) Composition or reconstruction of a new seismic data trace with the new selected set of wavelets. The new reconstructed seismic data trace is the resulting seismic data trace. It normally have much higher signal to noise ratio than the original seismic data trace.09-25-2008
200901803513-D TAU-P INTERPOLATION - Methods and apparatus for removing noise from signal traces collected during a seismic gather, particularly removing the aliased energy in the time-slowness (tau-P) domain so that aliasing noise does not lead to high noise levels in the inverse transformed data are provided. Removal of the aliasing noise may provide for quieter seismic traces and may increase the likelihood for successful three-dimensional (3-D) tau-P interpolation and detection of seismic events.07-16-2009
20120014216Time reverse reservoir localization - A method and system for processing synchronous array seismic data includes acquiring synchronous passive seismic data from a plurality of sensors to obtain synchronized array measurements. A reverse-time data process is applied to the synchronized array measurements to obtain a plurality of dynamic particle parameters associated with subsurface locations. These dynamic particle parameters are stored in a form for display. Maximum values of the dynamic particle parameters may be interpreted as reservoir locations. The dynamic particle parameters may be particle displacement values, particle velocity values, particle acceleration values or particle pressure values. The sensors may be three-component sensors. Zero-phase frequency filtering of different ranges of interest may be applied. The data may be resampled to facilitate efficient data processing.01-19-2012
20100309749METHODS AND SYSTEMS FOR MULTICOMPONENT TIME-LAPSE SEISMIC MEASUREMENT TO CALCULATE TIME STRAINS AND A SYSTEM FOR VERIFYING AND CALIBRATING A GEOMECHANICAL RESERVOIR SIMULATOR RESPONSE - A system, method, and computer program configured to provide an electronic method for seismic time-lapse characterization of an underground formation are provided. The method includes decomposing, with microprocessor executing a predefined set of instructions stored in a memory, baseline and monitor seismic survey data of a formation into a four dimensional Clifford Algebraic form; extracting, via the microprocessor, time delays from a matrix of decomposed sensor measurement vectors generated based on the four dimensional Clifford Algebra form; and determining, via the processor, time strains for the underground formation from differences in the extracted time delays from the matrix before displaying the determined time strains for the underground formation to a user via a monitor or a hard copy printed document. A procedure is also provided to calibrate and refine the static and dynamic models of an underground formation using the results from the seismic time-lapse characterization.12-09-2010
20110141848Optimizing a Seismic Survey for Source Separation - A technique includes determining at least one parameter that characterizes a seismic survey in which multiple interfering seismic sources are fired and seismic sensors sense energy that is produced by the seismic sources. The determination of the parameter(s) includes optimizing the seismic survey for separation of the sensed energy according to the seismic sources.06-16-2011
20110194377APPARATUS AND METHOD FOR IMAGING A SUBSURFACE USING ACCUMULATED ENERGY OF WAVEFIELD - Provided is an apparatus of imaging a subsurface of a target area. The apparatus includes: an observed wavefield acquiring unit configured to acquire an observed wavefield for a target area based on seismic data; a parameter storage configured to store a characteristic parameter for the target area; a modeled wavefield creator configured to create a modeled wavefield corresponding to the observed wavefield using the characteristic parameter stored in the parameter storage; an energy calculator configured to calculate accumulated energies of the observed wavefield and the modeled wavefield, wherein the accumulated energies are defined as energies accumulated over time with respect to the observed wavefield and the modeled wavefield; and a parameter updating unit configured to update the characteristic parameter stored in the parameter storage such that a difference between the accumulated energy of the observed wavefield and the accumulated energy of the modeled wavefield is minimized.08-11-2011
20120033529OPTIMAL SOURCE SIGNATURE DETERMINATION - The invention relates to processing seismic data that includes signals from at least two sources and typically three or four sources where source separation is necessary for geophysical analysis. Specifically, the present invention is an analytical technique that quickly creates a more accurate source signature delivered by analysis of the source generated data contamination present in the separated data. The technique is to invert a segment of the data using a seed source signature and compute an error that reflects the generated data contamination observed in the separated source data. The source signature is iteratively revised as the segment is continually inverted with the goal of finding the optimal source signature that provides the lowest computed error. The source signature that provides the lowest error is, or is very close to, the true source signature and is then used in the separation process for the entire composite data set. This will provide much more information for geophysical interpretation.02-09-2012
20110199858ESTIMATING INTERNAL MULTIPLES IN SEISMIC DATA - A method for estimating internal multiples in seismic data. The method includes selecting a subset from a set of regularly sampled seismic data based on a low-discrepancy point set. The method may then include integrating one or more depth integrals of the inverse-scattering internal multiple prediction (ISIMP) algorithm over each data point in the subset. After integrating the depth integrals, the method may then include integrating a function of the integrated depth integrals using a quasi-Monte Carlo (QMC) integration over the subset, thereby generating an estimate of the internal multiples.08-18-2011
20090296523JOINTLY INTERPOLATING AND DEGHOSTING SEISMIC DATA - A technique includes representing actual measurements of a seismic wavefield as combinations of an upgoing component of the seismic wavefield and ghost operators. Interpolated and deghosted components of the seismic wavefield are jointly determined based at least in part on the actual measurements and the representation.12-03-2009
20100271903Extending the Coverage of VSP/CDP Imaging by Using First-Order Downgoing Multiples - First-order free-surface multiples recorded in VSP data or reverse VSP data are processed using VSP/CDP method to produce an image of the subsurface. This image produces a larger coverage than that obtained in 3-C 3-D processing of reflection data acquired in the VSP.10-28-2010
20080291781PROCESS AND PROGRAM FOR CHARACTERISING EVOLUTION OF AN OIL RESERVOIR OVER TIME - Evolution of an hydrocarbon reservoir in the process of producing is carried out by co-analyzing the changes in the propagation times and seismic amplitudes of a seismic wavelet along propagation paths in the ground. A base survey of the reservoir is provided, with a set of seismic traces at a first time T associated to a first velocity field V11-27-2008
20110205843METHOD OF PROCESSING SEISMIC DATA - One or more methods and systems for processing seismic data to improve resolution of seismic images are provided. In one or more embodiments the method can include constructing a plurality of ray path traces. Each ray path trace can have a first portion for a first vertical location and a second portion for a second vertical location. An impinging angle for each ray path trace is held constant for the first vertical location and the second vertical location.08-25-2011
20110188347VOLUME IMAGING FOR HYDRAULIC FRACTURE CHARACTERIZATION - Methods and systems are described for measuring effects of a hydraulic fracturing process. The techniques can utilizes cross-well seismic technology, such as used in Schlumberger's DeepLook-CS tools and service, or in some case surface to borehole or borehole to surface seismic technology. The downhole seismic sources at known locations can be conventional sources or can be other types of equipment operating at known locations such as perforation guns. The source is activated or swept creating energy which is transmitted through the formation. The energy is recorded at the receiver array and processed to yield a tomographic image indicating changes in the subterranean formation resulting from the hydraulic fracturing process. The process can be performed pre and post hydraulic fracture stimulation to generate a difference image of propped fractures in the reservoir.08-04-2011
20100020640DYNAMIC SOURCE PARAMETER SELECTION FOR SEISMIC VIBRATOR DATA ACQUISITION - A method and system of operating single vibrator source points for seismic data acquisition includes acquiring real-time field survey locations for a first plurality of seismic vibrators, determining at least one geometrical relationship between each of the first plurality of seismic vibrators as a function of the field survey locations, selecting a second plurality of seismic vibrators from the first plurality of vibrators as a function of the at least one geometrical relationship, selecting source parameter data for the second plurality of seismic vibrators as a function of the field survey locations and driving the second plurality of seismic vibrators to propagate seismic energy into the earth. A third plurality of vibrators is selected based on geometrical relationships and associated source parameters are determined based on vibrator locations. Multiple vibrator groups may acquire data continuously without interruption.01-28-2010
20120069707METHOD FOR MONITORING A SUBSOIL ZONE, PARTICULARLY DURING STIMULATED FRACTURING OPERATIONS - The invention relates to a method for monitoring a subsoil zone, wherein a plurality of receivers are arranged on a surface of the soil or near said surface, straight above a geological zone to be monitored, comprising the following steps: generating a set of reference seismic data recording seismic data by means of said receivers; correlating the seismic data recorded (03-22-2012
20090080287Method for Estimating Absorption Parameter Q(T) - A method and apparatus for a method for generating an estimated value of absorption parameter Q(t). In one embodiment, the method includes receiving an input seismic trace, applying a time variant Fourier transform to the input seismic trace to generate a time variant amplitude spectrum of the input seismic trace, dividing the natural logarithm of the time variant amplitude spectrum by −πf, and performing a power series approximation to the result with an index starting from one to generate an estimated value of R(t). R(t) is a ratio between traveltime t and the absorption parameter Q(t). The method further includes dividing t by R(t) to generate the estimated value of the absorption parameter Q(t).03-26-2009
20130215716Integrated Passive and Active Seismic Surveying Using Multiple Arrays - Microseismic mapping using buried arrays with the integration of passive and active seismic surveys provides enhanced microseismic mapping results. The system is initially set up by recording seismic data with the buried array installation while shooting a significant portion of the 3D surface seismic survey. The 3D surface seismic survey provides the following data: shallow 3D VSP data from the buried arrays; P-wave and converted wave data for the area covered by the buried array that benefits from the planned data integration processing effort; and microseismic data and associated analysis.08-22-2013
20090122643METHOD FOR ACOUSTIC IMAGING OF THE EARTH'S SUBSURFACE USING A FIXED POSITION SENSOR ARRAY AND BEAM STEERING - A method for seismic surveying includes disposing a plurality of seismic sensors in a selected pattern above an area of the Earth's subsurface to be evaluated. A seismic energy source is repeatedly actuated proximate the seismic sensors. Signals generated by the seismic sensors, indexed in time with respect to each actuation of the seismic energy source are recorded. The recorded signals are processed to generate an image corresponding to at least one point in the subsurface. The processing includes stacking recordings from each sensor for a plurality of actuations of the source and beam steering a response of the seismic sensors such that the at least one point is equivalent to a focal point of a response of the plurality of sensors.05-14-2009
20100149916Processing Seismic Vibrator Signals Having Distinguishing Signatures - A method and apparatus for generating a seismic source signal are provided for generating energy in the form of a plurality of time sequence vibratory signals, the vibratory signals being partitioned as a function of time and/or frequency, wherein each of the plurality of signals comprises a distinguishing signature. The partitioned vibratory signals are emitted into a terrain of interest as seismic source signals for conducting a seismic survey06-17-2010
20100149915Acquiring Seismic Vibrator Signals Having Distinguishing Signatures - A method and apparatus for generating a seismic source signal are provided for generating energy in the form of a plurality of time sequence vibratory signals, the vibratory signals being partitioned as a function of time and/or frequency, wherein each of the plurality of signals comprises a distinguishing signature. The partitioned vibratory signals are emitted into a terrain of interest as seismic source signals for conducting a seismic survey.06-17-2010
20100157732Time Reverse Reservoir Localization - A method and system for processing synchronous array seismic data includes acquiring synchronous passive seismic data from a plurality of sensors to obtain synchronized array measurements. A reverse-time data process is applied to the synchronized array measurements to obtain a plurality of dynamic particle parameters associated with subsurface locations. These dynamic particle parameters are stored in a form for display. Maximum values of the dynamic particle parameters may be interpreted as reservoir locations. The dynamic particle parameters may be particle displacement values, particle velocity values, particle acceleration values or particle pressure values. The sensors may be three-component sensors. Zero-phase frequency filtering of different ranges of interest may be applied. The data may be resampled to facilitate efficient data processing.06-24-2010
20100157730METHOD OF SUBSURFACE IMAGING USING MICROSEISMIC DATA - A method of subsurface imaging is disclosed, the method involving using input data relating to the geometry of a fracture in a subsurface medium, mechanical properties of the medium and in-situ stress states in the medium, to model the behaviour of the fracture and obtain predicted information relating to deformation of the fracture. The predicted information is then used to constrain the interpretation of measured microseismic data caused by movement of the fracture to determine characteristics of the movement and/or failure of the fracture.06-24-2010
20100157729Seismic Method For Vehicle Detection And Vehicle Weight Classification - A system is provided for detecting the passage of vehicles and the classification thereof by weight using geophone outputs and a unique density measurement in which the number of peaks of the geophone signal above a predetermined threshold over a number of time frames indicates the presence of a vehicle, with the number of time frames in which the density exceeds the threshold indicating whether the vehicle is a heavy vehicle such as a tank, or a light vehicle such as a car, with the threshold eliminating both manmade and natural noise, as well as distinguishing seismic vibrations due to personnel and animals. In one embodiment, various thresholds are utilized to detect the onset of vehicle presence and the end of the event.06-24-2010
20100260011CADENCE ANALYSIS OF TEMPORAL GAIT PATTERNS FOR SEISMIC DISCRIMINATION - Systems, methods, and apparatus are described that provide for analysis of seismic data. Features of temporal gait patterns can be extracted from seismic/vibration data. A mean temporal gait pattern can be determined. A statistical classifier can be used to model features of the data. The model can be used to classify the data. As a result, discrimination of seismic sources can be performed. Systems for discrimination of seismic data are also described. A system can include a vibration sensor system configured and arranged to detect vibrations. A system can also include a processor system configured and arranged to receive data from the vibration sensor, recognize the seismic data as belonging to a particular class of seismic data, and produce an output signal corresponding to the recognized particular class of seismic data.10-14-2010
20100238765RESERVOIR CHARACTERIZATION FROM MULTICOMPONENT MICROSEISMIC DATA - A method for determining seismic anisotropy of subsurface rock formations includes measuring passive seismic signals at a plurality of locations above an area of the Earth's subsurface to be surveyed. The compressional- and shear-wave arrival times from at least one origin location of a seismic event occurring in the subsurface are determined from the measured seismic signals. The arrival times are inverted to obtain values of the seismic anisotropy parameters.09-23-2010
20090116336Determining Orientation For Seafloor Electromagnetic Receivers - Method for updating a velocity model (05-07-2009
20110128817GEOPHYSICAL SIGNAL PROCESSING - A method of processing geophysical signals obtained by monitoring the response of the earth to an source using a plurality of receivers is described including the evaluation of sums or integrals of functions of weighted signal values over a one or multidimensional domain such that the domain is split into a plurality of simplices and the signal values are interpolated across the simplices using a non-linear approximation of the function, the approximation including signals and gradients of the signals, and the evaluated sums or integrals are used to obtain a representation of characteristics of the earth.06-02-2011
20100039893METHOD FOR SEISMIC MONITORING OF A FORMATION HYDRAULIC FRACTURING - The invention relates to oil-gas engineering, in particular to maintaining wells in the oil-gas industry and, more specifically the hydraulic fracturing seismic monitoring.02-18-2010
20090073807GENERATING SEISMIC VIBRATOR SIGNALS - A method and apparatus for generating a seismic source signal are provided for generating energy in the form of a plurality of time sequence vibratory signals, the vibratory signals being partitioned as a function of time and/or frequency, wherein each of the plurality of signals comprises a distinguishing signature. The partitioned vibratory signals are emitted into a terrain of interest as seismic source signals for conducting a seismic survey.03-19-2009
20110128818EXTRACTION OF DISCRETE RECORDS FROM CONTINUOUS SEISMIC RECORDINGS - An adaptive signal separation is provided that isolates signal data and listening data from multiple continuous overlapping seismic signals.06-02-2011
20110110190METHOD FOR VELOCITY MODEL BUILDING AND ANALYSIS - Method for velocity model building and analysis using wavefield-coordinates reflection operators in wave-equation migration or reverse-time migration.05-12-2011
20090067286DISPERSION EXTRACTION FOR ACOUSTIC DATA USING TIME FREQUENCY ANALYSIS - This invention pertains to the extraction of the slowness dispersion characteristics of acoustic waves received by an array of two or more sensors by the application of a continuous wavelet transform on the received array waveforms (data). This produces a time-frequency map of the data for each sensor that facilitates the separation of the propagating components thereon. Two different methods are described to achieve the dispersion extraction by exploiting the time frequency localization of the propagating mode and the continuity of the dispersion curve as a function of frequency. The first method uses some features on the modulus map such as the peak to determine the time locus of the energy of each mode as a function of frequency. The second method uses a new modified Radon transform applied to the coefficients of the time frequency representation of the waveform traces received by the aforementioned sensors. Both methods are appropriate for automated extraction of the dispersion estimates from the data without the need for expert user input or supervision03-12-2009
20110044132Removing Ground-Roll from Geophysical Data using Source-Receiver Interferometry - A method for processing geophysical data. The method includes applying a first interferometry on an estimate of a direct ground roll between a receiver location and one or more boundary source locations and an estimate of a direct ground roll between one or more boundary receiver locations and each boundary source location to generate an interferometric estimate of a direct ground roll between the receiver location and each boundary receiver location. The method then includes applying a second interferometry on geophysical data between the source location and each boundary receiver location and the interferometric estimate of the direct ground roll between the receiver location and each boundary receiver location to generate an interferometric estimate of a direct and scattered ground roll between the source location and the receiver location. After applying the second interferometry, the method then includes removing the interferometric estimate of the direct and scattered ground roll between the source location and the receiver location from geophysical data acquired at the receiver location due to a source at the source.02-24-2011
20110044131Method for Passive Seismic Emission Tomography Including Polarization Correction for Source Mechanism - A method for seismic event mapping includes selecting a plurality of subvolumes representing possible locations of origin of a seismic event in the Earth's subsurface. For each subvolume a plurality of possible directions of motion of subsurface formations is selected. For each subvolume and each possible direction of motion, polarity correction is applied to seismic signals recorded at a plurality of positions proximate a volume of the Earth's subsurface to be evaluated. The polarity correction is based on the direction of motion and the position of each seismic sensor with respect to the subvolume. The recorded, polarity corrected seismic signal recordings are time aligned. The time aligned recordings are summed. A most likely direction of motion and subvolume position are determined based on a selected attribute of the summed, time aligned seismic signals.02-24-2011
20110085418Joint Interpretation of Rayleigh Waves and Remote Sensing for Near-Surface Geology - A computer implemented technique for use in seismic data interpretation and, more particularly, with respect to near-surface geological structures, includes a computer-implemented method, including: jointly interpreting a plurality of complementary data sets describing different attributes of a near-surface geologic structure; and ascertaining a near-surface geomorphology from the joint interpretation. In another aspect, the technique includes a program storage medium encoded with instructions that, when executed, perform such a method. In yet another aspect, the method includes a computing apparatus programmed to perform such a method.04-14-2011
20110242937Method for separating up and down propagating pressure and vertical velocity fields from pressure and three-axial motion sensors in towed streamers - A measured pressure field, a measured vertical velocity field, and two measured orthogonal horizontal velocity fields are obtained. A programmable computer is used to perform the following. A scaling factor is determined from water acoustic impedance, the measured pressure field, and the horizontal velocity fields. One of the measured pressure field and measured vertical velocity field is combined with one of the measured vertical velocity field scaled by the scaling factor and the measured pressure field scaled by the scaling factor, generating one of up-going and down-going pressure and velocity wavefields.10-06-2011
20110085417String of Sensor Assemblies Having a Seismic Sensor and Pressure Sensor - A system includes an electrical medium and a string of sensor assemblies having corresponding outputs connected to the electrical medium, where at least one of the sensor assemblies includes a seismic sensor to measure seismic waves propagated through a subterranean structure, and a pressure sensor. The sensor assembly further includes at least one matching circuit connected to an output of at least one of the seismic sensor and pressure sensor, where the at least one matching circuit is configured to suppress noise. An output signal of the at least one matching circuit is connected to the electrical medium to produce a combined signal that is representative of characteristics of the subterranean structure and in which the noise is suppressed.04-14-2011
20090022010EARTH ANALYSIS METHODS, SUBSURFACE FEATURE DETECTION METHODS, EARTH ANALYSIS DEVICES, AND ARTICLES OF MANUFACTURE - Earth analysis methods, subsurface feature detection methods, earth analysis devices, and articles of manufacture are described. According to one embodiment, an earth analysis method includes engaging a device with the earth, analyzing the earth in a single substantially lineal direction using the device during the engaging, and providing information regarding a subsurface feature of the earth using the analysis.01-22-2009
20080232195Apparatus and Method for Processing Geophysical Information - A seismic information processing method for determining a property related to an earth subsurface structure includes performing a first processing operation on geophysical information using a computer operating according to a first processing parameter set and generating a first result from the first processing operation. The method may include performing a second processing operation on the first result using the computer and generating a second result from the second operation. At least one measurement point of the second result is evaluated using the computer. The first processing parameter set may be varied at least once to a second processing parameter for processing the geophysical information. The first operation, the second operation and the evaluation are repeated using the second processing parameter set. At least one of the first result, the second result and the evaluation is used for generating the property relating to the earth subsurface structure.09-25-2008
20090168600SEPARATING SEISMIC SIGNALS PRODUCED BY INTERFERING SEISMIC SOURCES - A technique includes obtaining seismic data indicative of measurements acquired by seismic sensors of a composite seismic signal produced by the firings of multiple seismic sources. The technique includes associating models that describe geology associated with the composite seismic signal with linear operators and characterizing the seismic data as a function of the models and the associated linear operators. The technique includes simultaneously determining the models based on the function and based on the determined models, generating datasets. Each dataset is indicative of a component of the composite seismic signal and is attributable to a different one of the seismic sources.07-02-2009
20080205193Method for continuous sweeping and separation of multiple seismic vibrators - A method for simultaneously operating multiple seismic vibrators using continuous sweeps (little or no “listening” time between sweeps) for each vibrator, and recovering the separated seismic responses for each vibrator with the earth signature removed. Each vibrator is given a unique, continuous pilot signal. The earth response to the motion of each vibrator is measured or estimated. The vibrator motion records for each vibrator and the combined seismic data record for all the vibrators are parsed into separate shorter records. The shorter records are then used to form a system of simultaneous linear equations in the Fourier transform domain, following the HFVS method of Sallas and Allen. The equations are then solved for the separated earth responses.08-28-2008
20100329077REGULARISATION OF IRREGULARLY SAMPLED SEISMIC DATA - There is provided a method of spatially shifting seismic signals acquired through a seismic survey using the steps of identifying within the signals a set of N actual locations of seismic receivers and corresponding N seismic signals received by the set of seismic receivers; identifying a set of N′ desired locations of seismic receivers; and determining a set of N′ signal values at said N′ desired locations by evaluating for each of said N′ signal values a weighted sum of the N seismic signals, wherein the weights are at least partly determined by the relative distance between pairs of locations selected from said set of N actual locations of seismic receivers.12-30-2010
20110096626Machine, Program Product and Method to Determine a First Arrival of a Seismic Trace - Embodiments of a machine, program product and computer implemented method to perform a process of picking an initial first arrival from at least one trace of the plurality of seismic traces and a process of refining the initial first arrival pick based upon a comparison of the initial first arrival pick with first arrival pick of adjacent traces is disclosed. Such embodiments perform the steps of: centering a main time window around each of the plurality of possible first arrivals for the seismic traces, setting a start of the time window to zero, transforming the plurality traces into a plurality of peak spike traces; dividing the main window into a plurality of sub-windows; comparing each of the plurality of peak spikes in the sub-window, determining the first arrivals, and determining if the first arrival is a desired pick.04-28-2011
20110096625Methods to Process Seismic Data Contaminated By Coherent Energy Radiated From More Than One Source - This invention discloses methods of processing data using a computer to separate out geophysical exploration response at receivers corresponding to one source among many sources by determining at least one spatio-temporal variant directional propagation attribute of the responses at receivers corresponding to the one source and by decomposition or filtering process using the determined attribute.04-28-2011
20100165790METHOD FOR DETERMINATION OF THE OIL FORMATION'S WATER-FLOODING AREA RADIUS IN THE WELLBORE ZONE - A method includes installing at least one grounded electrode at a certain distance away from the well sufficient enough to avoid electrical breakdowns and connecting a high-voltage electric capacity meter to a wellhead and to said grounded electrode. A voltage pulse between the wellhead and the electrode. An electric capacity is measured before flooding and in the process of flooding. The oil formation water-flooding area radius value is determined by the flooded area capacity variation in time.07-01-2010
20100165789METHOD FOR DETERMINATION OF THE OIL FORMATION WATER-FLOODING AREA PATTERN AND SIZE IN THE WELLBORE ZONE - The method for the determination of an oil formation's water-flooding area pattern and size in a borehole zone comprises grounded electrode installation at a certain distance away from the borehole sufficient enough to avoid electrical breakdowns. An electrical pulse generator is connected to a wellhead and to the electrode. A voltage pulse is applied between the wellhead and the electrode and electrical and/or acoustic response to electrical disturbances are measured. Pattern and size of the oil formation's water-flooding area is determined by an acquisition and processing system using a 07-01-2010
20110261648FUSING GEOPHYSICAL DATA REPRESENTING A GEOPHYSICAL SPACE - Geophysical data representing at least first and second overlapping geophysical spaces may be aggregated. A first set of geophysical data representing the first geophysical space and a second set of geophysical data representing the second geophysical space may be obtained. The second set of geophysical data may be separate and discrete from the first set of geophysical data. The first set of geophysical data may be transformed from a first parametric domain to a third parametric domain, while the second set of geophysical data may be transformed from a second parametric domain to the third parametric domain. The first set of geophysical data may be fused with the second set of geophysical data in the third parametric domain to create a fused set of geophysical data. The fused set of geophysical data may be transformed from the third parametric domain to a fourth parametric domain.10-27-2011
20110051553DETERMINING THE QUALITY OF A SEISMIC INVERSION - A method for evaluating a quality of a seismic inversion. The method includes performing a first match between seismic data and borehole seismic data at one or more borehole locations to generate an estimate of a wavelet in the seismic data. The method then performs a seismic inversion on the seismic data using the estimate of the wavelet to generate inverted seismic data. After performing the seismic inversion, the method converts the inverted seismic data into one or more reflectivity traces. The method then includes performing a second match between the one or more reflectivity traces and one or more traces in the seismic data and performing a third match between the one or more reflectivity traces and one or more traces in the borehole seismic data. After performing the second and third matches, the method determines the quality of the seismic inversion based on the first match, the second match, the third match or combinations thereof.03-03-2011
20120113750NON-HYPERBOLIC CORRECTION OF SEISMIC DATA - A method for improving seismic images by correction of distortions in the underlying seismic data caused by a near-surface anomaly that produces a non-hyperbolic move-out component of the seismic reflection below the anomaly includes the steps of: 05-10-2012
20120113749Computing a Calibration Term Based on Combining Divergence Data and Seismic Data - Divergence data is received from a divergence sensor and seismic data is received from seismic sensors, where the divergence sensor and seismic sensors are part of a sensor assembly. A calibration term is computed based on combining the divergence data and the seismic data, where the calibration term includes a first parameter that is related to a characteristic of the sensor assembly, and a second parameter that is related to a characteristic of a near-surface subterranean medium.05-10-2012
20120044784DETERMINING A POSITION OF A GEOLOGICAL LAYER RELATIVE TO A WAVELET RESPONSE IN SEISMIC DATA - Determining geological layer location in a subterranean formation, including receiving seismic data representing an interaction of the geological layer with propagation of a seismic wave, identifying a source wavelet representing a portion of the seismic wave impinging on a boundary of the geological layer, providing a geological layer template of the geological layer including primary and secondary reflection interfaces associated with reflectivity based on material properties of the geological layer, generating a wavelet response template by applying the source wavelet to the geological layer template using a mathematical convolution operation to model seismic wave interference caused by the primary and secondary reflection interfaces, identifying an extremum of the seismic data, and determining, based on the extremum, the location of the geological layer in the subterranean formation using the wavelet response template.02-23-2012
20100020641DYNAMIC SOURCE PARAMETER SELECTION FOR SEISMIC VIBRATOR DATA ACQUISITION - A method and system of operating single vibrator source points for seismic data acquisition includes acquiring real-time field survey locations for a first plurality of seismic vibrators, determining at least one geometrical relationship between each of the first plurality of seismic vibrators as a function of the field survey locations, selecting a second plurality of seismic vibrators from the first plurality of vibrators as a function of the at least one geometrical relationship, selecting source parameter data for the second plurality of seismic vibrators as a function of the field survey locations and driving the second plurality of seismic vibrators to propagate seismic energy into the earth. A third plurality of vibrators is selected based on geometrical relationships and associated source parameters are determined based on vibrator locations. Multiple vibrator groups may acquire data continuously without interruption.01-28-2010
20090290449Processing Seismic Data Using Combined Regularization and 4D Binning - To process seismic data, a combined four-dimensional (4D) binning and regularization procedure is performed on the seismic data, where the combined 4D binning and regularization procedure includes computing measures associated with regularization of the seismic data, computing measures associated with 4D binning, and processing the seismic data according to the regularization measures and 4D binning measures.11-26-2009
20120106294Optimization Approach to Q-Factor Estimation From VSP Data - A zero-offset VSP survey is carried out with spaced apart receivers located in a vertical wellbore. Spectra of the signals at the receivers following wavefield separation are estimated. An absorption coefficient is estimated using differences in spectra between all pairs of receivers.05-03-2012
20120106293IMAGE BASED EFFECTIVE MEDIUM MODELING OF THE NEAR SURFACE EARTH FORMATION - This disclosure presents a method that utilizes the seismic image of the near-surface formation to estimate an effective velocity field equivalent to the unknown true velocity field of the soil column, such that the statics shifts derived from the effective velocity field are essentially the same as the statics shifts that would have been computed using the unknown true velocity field. The effective velocity field derived statics shifts can be used to correct distortions caused by the near-surface formation and restore the sesimic image of the subsurface formation.05-03-2012
20120014215Time reverse reservoir localization with borehole data - A method and system for processing synchronous array seismic data includes acquiring synchronous passive seismic data from a plurality of sensors to obtain synchronized array measurements. A reverse-time data process is applied to the synchronized array measurements to obtain a plurality of dynamic particle parameters associated with subsurface locations. These dynamic particle parameters are stored in a form for display. Maximum values of the dynamic particle parameters may be interpreted as reservoir locations. The dynamic particle parameters may be particle displacement values, particle velocity values, particle acceleration values or particle pressure values. The sensors may be three-component sensors. Zero-phase frequency filtering of different ranges of interest may be applied. The data may be resampled to facilitate efficient data processing.01-19-2012
20100254218Method and Apparatus for Estimating Formation Permeability and Electroacoustic Constant of an Electrolyte-Saturated Multi-Layered Rock Taking Into Account Osmosis - An acoustic source on a logging tool is used to generate acoustic waves in a borehole. Acoustic detectors on the logging tool measure the generated acoustic waves. Electrodes on the logging tool are used to measure the potential resulting from the generated acoustic wave. The output of the hydrophones and the electrodes corresponding to Stoneley wave components of the acoustic wave are processed to provide an estimate of formation permeability, acoustoelectric constant, and a velocity of a propagating second compressional wave in the formation.10-07-2010
20090296524Converted Mode Seismic Survey Design - Method for designing a converted mode (PS or SP) seismic survey to accomplish specified vertical and lateral resolution objectives at target depth. An equation (181) is provided for determining the minimum bandwidth required for a desired vertical resolution at a selected scattering angle, as a function of incident and reflected wave velocities, one of which is the P-wave velocity and the other is the S-wave velocity. A second equation (182) is provided for determining migration acceptance angle from the desired vertical and lateral resolutions. Source and receiver apertures may then be determined by ray tracing. Finally, a third equation (183) is provided for the maximum bin size to avoid aliasing, given the migration acceptance angle and a maximum frequency needed to achieve the bandwidth requirement. Source and receiver spacing may then be based on the maximum bin size.12-03-2009
20110069580MEASURING AND MODIFYING DIRECTIONALITY OF SEISMIC INTERFEROMETRY DATA - Methods and apparatuses are disclosed for replacing the individual receivers used with a seismic interferometry process with an array of seismic receivers and then manipulating the array data in order to measure and modify the typical non-uniform directionality function of the background seismic energy. The non-uniform directionality function is a significant cause of noise with seismic interferometry. Furthermore, the array of receivers may be used to significantly enhance the preferred reflection energy and damp undesirable near surface energy. The directionality function may be modified by using an array of receivers for the virtual source location of seismic interferometry to measure the non-uniform directionality function, generating multiplication factors, and applying the multiplication factors to convert the measured directionality function into a desired directionality function.03-24-2011
20120155217SEISMIC ACQUISITION USING NARROWBAND SEISMIC SOURCES - There is provided herein a system and method of seismic data collection for land and marine data that utilizes narrowband to monochromatic low-frequency non-impulsive sources designed to optimize the ability of migration/inversion algorithms to image the subsurface of the Earth, in particular, full-waveform inversion.06-21-2012
20110103184TECHNIQUE AND SYSTEM FOR DERIVING A TIME LAPSE LOW FREQUENCY MODEL USING BOTH SEISMIC DATA AND A FLOW SIMULATION MODEL - A technique includes determining a change in an elastic property of a region of interest at a second time relative to a first time based on a flow simulation model. The technique includes scaling the determined change in the elastic property based on data acquired in a seismic survey.05-05-2011
20090059721PASSIVE REFLECTIVE IMAGING FOR VISUALIZING SUBSURFACE STRUCTURES IN EARTH AND WATER - A system and method is provided that uses signals from a plurality of seismic sensors to define an acoustic lens for subsurface imaging. More specifically signals provided by an array of sensors/geophones may be utilized to form an acoustic lens that can be focused on a subterranean point by properly adjusting the signals recorded at each sensor prior to summation of those signals. To form such an acoustic lens, each of the seismic sensors is moved onto a hypothetical acoustic lens surface (e.g., spherical surface) having a focal point located on the subterranean point of interest in order to calculate a time delay for each signal. Once the signals for each sensor is time-delayed, information in the time-delayed signals, which is received from the point of interest, may be temporally aligned. Accordingly, the time delayed signals may be combined to generate reflection information for the point of interest.03-05-2009
20120075954Device and Method for Calculating 3D Angle Gathers from Reverse Time Migration - A method for calculating angle domain common image gathers (ADCIGs). The method includes calculating a source wavefield p03-29-2012
20120257476SEISMIC IMAGE ENHANCEMENT - A method can include accessing seismic data; providing a wave function that defines, at least in part, a correlation window length; generating local autocorrelation functions for the seismic data using the correlation window length; performing cross-correlations between the wave function and each of the local autocorrelation functions to provide local cross-correlation coefficient values; determining second derivatives of the local cross-correlation coefficient values to provide local second derivative values; and rendering the local second derivative values to a display. Various other apparatuses, systems, methods, etc., are also disclosed.10-11-2012
20120263015DEVICE AND METHOD FOR CALCULATING 3D REVERSE TIME MIGRATION IN TILTED ORTHORHOMBIC MEDIA - A computing device, computing medium and method for generating an image of a tilted orthorhombic medium. The method includes receiving seismic data related to the tilted orthorhombic medium; calculating a wave propagation with a processing device by applying a second-order equation for reverse time migration to the seismic data to generate a tilted orthorhombic wave propagation; and generating the image of the tilted orthorhombic medium based on the tilted orthorhombic wave propagation.10-18-2012
20100254217Method for Determining the Fluid/Pressure Distribution of Hydrocarbon Reservoirs from 4D Seismic Data - A method including analyzing seismic data relating to a producing hydrocarbon reservoir is disclosed. The seismic data includes first and second sets of seismic data obtained at different times. An interval composed substantially of hard rock is identified in the hydrocarbon reservoir. 4D seismic attributes for the region are calculated. Rock physics relationships are applied to seismic data related to the interval according to the permeability associated therewith. A fluid saturation change or a pressure change of the interval is inferred based on outputs of the first or second sets of rock physics relationships and the calculated 4D attributes for the interval. The inferred fluid saturation change or pressure change of the interval is outputted.10-07-2010
20120140593TIME-LAPSE SEISMIC COMPARISONS USING PRE-STACK IMAGING AND COMPLEX WAVE FIELD COMPARISONS TO IMPROVE ACCURACY AND DETAIL - A method, computer program product and system for improving the accuracy and detail in determining changes in properties associated with sub-surface geological structures. A first and a second time-lapse seismic data taken for a first and a second seismic survey, respectively, are received. If no calibration for the first and second time-lapse seismic data are needed, then an absolute time-lapse comparison is made. In the absolute time-lapse comparison, the time-lapse seismic data taken at a depth level below a reference level is compared with time-lapse seismic data taken at the reference level. If however, calibration is needed, then a residual time-lapse comparison is made. In the residual time-lapse comparison, the derived residual phase and amplitude differences at a depth level below the reference level are compared with the derived residual phase and amplitude differences at the reference level.06-07-2012
20130016582SYSTEM FOR EXPLORATION OF SUBTERRANEAN STRUCTURESAANM Fallet; TrulsAACI OsloAACO NOAAGP Fallet; Truls Oslo NOAANM Woods; ErlingAACI HafrsfjordAACO NOAAGP Woods; Erling Hafrsfjord NO - A system for communication through subterranean structures underneath a surface comprises at least one exploration tool adapted to penetrate into the underground, at least one transmitter, at least one receiver, and signal transfer means for transmitting signals between the exploration tool and a recording unit arranged overground, where at least one of the transmitter or receiver is integrated in the exploration tool. The exploration tool is a device which is able to penetrate into the underground in order to bring equipment into the underground independent of any existing or new wells.01-17-2013
20110158046SEISMIC DATA ACQUISITION AND PROCESSING QUALITY CONTROL - The present invention relates to producing a quality control measure for use during data acquisition and/or data processing of, preferably, seismic data. While or after obtaining the data, a surface consistent decomposition of the data is performed. From the surface consistent decomposition, one may compute a decomposed logarithmic spectra, and from the decomposed logarithmic spectra, one may compute one or more residua. An error attribute based on the one or more residua can be formulated, analyzed, and output. The error attribute can be used as a quality control measure or the analysis result can be used to produce a quality control measure.06-30-2011
20080232194Method of Seismic Surveying - A method enables the time required to complete a seismic survey and the noises recorded in the seismic data to be reduced. One aspect of the method includes actuating a first vibrator group to start a first sweep at time T09-25-2008
20080225641Multi-Component Seismic Data Processing - There is described a method of moveout or velocity analysis of seismic signals using the steps of obtaining such signals 09-18-2008
20130176819DEVICE AND METHOD FOR DE-BLENDING SIMULTANEOUS SHOOTING DATA - A device, medium and method for de-blending seismic data associated with a subsurface of the earth. The method includes a step of receiving seismic data “d” recorded with one or more land receivers, wherein the seismic data includes shot recordings generated by plural sources that are simultaneously actuated; a step of forming either a continuous receiver trace or trace segments from the received seismic data; a step of selecting plural overlapping spatial blocks that cover the surface shot locations; a step of assigning the shot recordings to the plural overlapping spatial blocks; a step of applying a mathematical technique to the recordings to determine de-blended data; and a step of generating an image of the subsurface based on the de-blended data.07-11-2013
20130094326SYSTEM AND METHOD FOR SEISMOLOGICAL SOUNDING - Systems and methods for seismological sounding with acoustic signals and, more particularly, systems and methods for performing geophysical surveys using spread spectrum acoustic waves generated by non-impulsive sources. A spread spectrum signal is generated and coupled to a medium that is to be sounded for propagation of an acoustic wave through the medium. One or more return signals are received from the medium that are generated by interaction between the acoustic wave and the medium. The return signals are possessed to obtain seismic sounding data describing the structural features of the medium.04-18-2013
20130100770Method for Imaging Microseismic Events Using an Azimuthally-dependent Focal Mechanism - Disclosed herein are various embodiments of methods and systems for determining the orientation and direction of first motion of a fault or fracture by optimizing an azimuthally-dependent attribute of signals generated by microseismic sources, comprising: recording microseismic data traces using a of sensors located at a plurality of sensor positions; subdividing the subsurface volume into spatial volumes corresponding to selected time intervals and comprising a plurality of voxels; for each voxel, applying a time shift to the microseismic data traces that is substantially equal to a travel time from each voxel to the corresponding sensor position, and determining for the voxel the orientation and direction of first motion of the fault or fracture corresponding to a maximum value for the voxel of at least one azimuthally-dependent attribute of the microseismic data traces.04-25-2013
20110273959Data Acquisition and Prestack Migration Based on Seismic Visibility Analysis - Seismic visibility analysis of selected subsurface structures is employed to determine surface locations offering high visibility of target events. These locations can then be used as a basis for acquiring additional seismic survey data and/or selecting existing traces for re-migration with more sophisticated migration methods. With either usage, the newly migrated data is expected to offer enhanced images of the target event. In some embodiments, the visibility determination includes using a wave equation based propagator to find, for each of multiple simulated shots, a reflection wavefield from the target event in a seismic model; and to calculate, for each of multiple receiver positions, a contribution signal from each reflection wavefield. The visibility determination further includes converting each contribution signal into a source-receiver visibility value. Because data acquisition and/or re-migration is limited to the selected region, the imaging effort for the target event is significantly reduced.11-10-2011
20130176820SURFACE-CONSISTENT AMPLITUDE AND DECONVOLUTION SIMULTANEOUS JOINED INVERSION - Methods and systems for a surface-consistent amplitude and deconvolution simultaneous joined inversion are described. A one-pass estimation using input trace data for generating gain and deconvolution operator based on a least squares iteration method. A series of iterations are performed simultaneously and independently estimating amplitude scalars and autocorrelation spectra with a common convergence criterion. The gain and deconvolution operator can further be used to correct the input trace data for pre-stack or stack imaging.07-11-2013
20120275267Seismic Data Processing - Provided is a method for processing seismic data. One exemplary embodiment includes the steps of obtaining a plurality of initial subsurface images; decomposing each of the initial subsurface images into components; identifying a set of components comprising one of (i) components having at least one substantially similar characteristic across the plurality of initial subsurface images, and (ii) components having substantially dissimilar characteristics across the plurality of initial subsurface images; and generating an enhanced subsurface image using the identified set of components. Each of the initial subsurface images is generated using a unique random set of encoding functions.11-01-2012
20110310701Seismic Telemetry and Communications System - A system for transmitting telemetry data between an underground structure and a location above the underground structure includes a network of receiving devices within the underground structure which gathers telemetry data from a data transmitter located within the underground structure. An underground broadcasting station in communication with the network of receiving devices includes an underground processing device for converting the telemetry data into an encoded impactor signal and a seismic generator in contact with the underground structure and driven by the encoded impactor signal to broadcast an encoded seismic signal through an adjacent earthen formation. The system includes a receiving station having a seismic sensor and a processing device. The seismic sensor is in contact with the earthen formation at a remote location substantially above the underground structure. The processing device is in communication with seismic sensor and can convert the received encoded seismic signal into telemetry data.12-22-2011
20080285383System and method for processing seismic data for interpretation - A method is provided for processing seismic data for interpretation. The method includes recording an original seismic data trace, decomposing the original seismic data trace into a set of predefined wavelets, and reconstructing a seismic data trace from, at least a subset of, the set of wavelets.11-20-2008
20130201793Vibrator source system for improved seismic imaging - A system for modeling the output signal emanating from a seismic vibrator based on a superposed collection of damped harmonic oscillators, whose critical parameters are determined from signals from accelerometers on the baseplate and reaction mass portions of the vibrator together with the input force (pilot sweep). This modeled output signal is a more accurate representation of the seismic signal that propagates into the earth and may be used in the cross-correlation process to significantly enhance the accuracy of the recorded seismic data. Additionally, by modeling the output signal on a shot by shot basis, any changes in the ground's surface can be monitored and/or documented, and, if required, the sweep parameters can be varied shot by shot for optimum performance.08-08-2013
20130208567PHASE MODULATION AND NOISE MINIMIZATION FOR SIMULTANEOUS VIBROSEIS ACQUISITION - An embodiment of the invention includes simultaneous drive signals whose respective phase angle offset(s) varies over a portion or duration of the simultaneous sweeps. Other embodiments are discussed herein.08-15-2013

Patent applications in class Signal analysis and/or correction

Patent applications in all subclasses Signal analysis and/or correction