Abstract: A method for determining upgoing pressure components of seismic signals from signals detected by combined pressure responsive sensors and motion responsive seismic sensors disposed in a plurality of laterally spaced apart streamers includes determining a threshold time at which angle of incidence error in the motion responsive signals in the cross-line direction falls below a selected threshold. Below the threshold time, the motion responsive signals are corrected for angle of incidence in the in-line and cross-line directions. Above the threshold time, the motion responsive signals are corrected for angle of incidence only in the in-line direction. Both sets of incidence corrected measured motion responsive signals, and the pressure responsive signals are used to determine upgoing or downgoing pressure components or upgoing or downgoing motion components of the measured motion responsive and pressure responsive seismic signals.

Abstract: A method of assessing acquisition errors in seismic images in a seismic data volume. The method includes selecting a seismic attribute in a seismic data volume and then stacking seismic quality image measurements taken along the selected attribute. The stacked measurements are then related on the basis of any vertical correlation and any vertically correlated feature is identified as a cobweb. Any identified cobwebs are removed from the seismic data volume.

Abstract: Method for processing a set of seismic cubes corresponding to the same acquisition zone and at different source/receiver offset and/or angle of incidence values, characterized in that at least one seismic cube is determined, which is an estimation of the component common to at least two seismic cubes corresponding to different offset and/or angle of incidence values.

Abstract: A technique includes obtaining particle motion data and pressure data that are acquired by seismic sensors while in tow. The sensors are part of a plurality of streamers, and the pressure and particle motion data contain surface ghosts. The technique includes processing the particle motion data and the pressure data to generate a data set that is indicative of a pressure wavefield at positions between the streamers and is substantially free of the surface ghosts.

Abstract: Certain embodiments of the present invention provide a system for improved signal processing within a remote sensor system. The system includes a detection component and a classification component. The detection component is adapted to detect an event. The classification component is adapted to classify the event based at least in part on a situation. Certain embodiments of the present invention provide a method for improved signal processing within a remote sensor system. The system includes determining a situation, detecting an event, and classifying the event based at least in part on a situation.

Abstract: The present invention incorporates the use of model-driven and data-driven methodologies to attenuate multiples in seismic data utilizing a prediction model which includes multiply-reflected, surface-related seismic waves. The present invention includes beam techniques and convolving a predicted multiples beam with a segment of a modeled pegleg beam to obtain a convolved multiples beam. The convolved multiples beam can then he deconvolved to attenuate the multiples that are present in the original input beam.

Abstract: Seismic image filtering machines, systems, program products, and computer implemented methods are provided to generate a filtered seismic image responsive to filtered seismic image data generated by attenuating coherent seismic noise from surface waves of an unfiltered wavefield constructed from unfiltered seismic image data through a single downward extrapolation of the unfiltered wavefield using a plurality of nonstationary convolution operators to perform localized filtering at each of a plurality of spatial locations of the unfiltered wavefield. Various embodiments, for example, can beneficially handle strong lateral velocity variations thus making various embodiments effective tools to remove complicated coherent seismic noise which is typically in the form of exponentially decaying evanescent waves.

Abstract: Certain embodiments of the present invention provide a system for improved signal processing within a remote sensor system. The system includes a detection component and a processing component. The detection component is adapted to detect an event and generate a signal based at least in part on the event. The processing component adapted to process a signal based at least in part on a situation. Certain embodiments of the present invention provide a method for improved signal processing within a remote sensor system. The method includes determining a situation, detecting an event, generating a signal based at least in part on the event, and processing the signal based at least in part on the situational parameter.

Abstract: Certain embodiments of the present invention provide a system for improved signal processing within a remote sensor system. The system includes a detection component and a processing component. The detection component is adapted to detect an event and generate a signal based at least in part on the event. The processing component adapted to determine an envelope of the signal based at least in part on a situation. Certain embodiments of the present invention provide a method for improved signal processing within a remote sensor system. The system includes detecting an event, generating a signal based at least in part on the event, and determining an envelope of the signal based at least in part on a situation.

Abstract: Systems and methods for enhancing the resolution of a seismic data image displayed on a face of a sampling probe. The enhanced image represents a maximum resolution of at least a portion of the seismic data image. The seismic data image is enhanced by extracting seismic data that are perpendicular to a reflection surface that is closest to a center of the sampling probe and positioning the extracted seismic data in a visible planar face of the sampling probe.

Abstract: A method for estimating seismic data from sources of noise in the earth surrounding a first seismic receiver and a second seismic receiver. The method includes calculating a Green's function G?(X1, X2) between a first seismic receiver X1 and a second seismic receiver X2 using interferometry. The first seismic receiver X1 is located at a distance away from the second seismic receiver X2. After calculating the Green's function G?(X1, X2), the method may include steps for determining an estimate of one or more non-physical wavefields present in the Green's function G?(X1, X2) and determining a filter to remove the non-physical wavefields from the Green's function G?(X1, X2) based on the estimate of the non-physical wavefields. The filter may then be applied to the Green's function G?(X1, X2) to obtain a Green's function G?(X1, X2) free of non-physical wavefields.

Abstract: Techniques are disclosed for determining the bearing from a three-axis geophone to a seismic source, such as a person or other man-made seismic source. In one embodiment, the techniques are implemented as a method that includes receiving outputs from a three-axis geophone (x axis, y axis and z axis outputs), computing a magnitude signal based on the x and y axis outputs, determining locations of each local peak in the magnitude signal, computing a bearing estimate for each peak, and computing a median of the bearing estimates. The resulting median bearing is an estimate of the bearing from the geophone to a target seismic source. In one such case, computing the magnitude signal based on the x and y axis outputs is performed in response to detecting the target seismic source in the phase-shifted z axis output.

Abstract: A method for data processing includes transforming measurement data acquired in the time domain during an oilfield operation into a second domain to produce transformed data; identifying distortions in the transformed data; removing the distortions from the transformed data; and transforming back from the second domain to the time domain to produce cleaned-up data. The transforming measurement data may use a Fourier transform or a wavelet transform. The method may further include compressing the cleaned-up data or reconstructing signals from the cleaned-up data. A method for data processing includes decomposing measurement data, which are acquired in an oilfield operation, using a low pass filter to produce a first dataset; decomposing the measurement data using a high pass filter to produce a second dataset; removing distortions from the second dataset to yield a corrected second dataset; and reconstructing a corrected dataset from the first dataset and the corrected second dataset.

Abstract: A technique for decomposing a recorded wave field represented in a set of multicomponent, marine seismic data centers around a computer-implemented method including: estimating the statistics of the noise terms in each one of a predetermined group of seismic measurements in a seismic data set acquired in a marine survey; modeling the physical propagation of a recorded wave field represented in the seismic data set from the estimated statistics; and estimating a directional component of the recorded wave field from the physical propagation model that minimizes error relative to the seismic measurements.

Abstract: A method for the quantitative characterization of a seabed sediment composition and a seabed's layered subbottom structure from at least one normal-incidence, single-channel reflection acoustic amplitude time series seismogram is disclosed. The method detects a plurality of reflections from subbottom interfaces in said seismograms, determines the traveltime, the polarity and the reflectivity of each detected reflection, determines the intrinsic attenuation of the sediment layer between pairs of adjacent reflections, and determines the acoustic properties, layer thicknesses and material properties of the seabed's layered subbottom structure as a function of said traveltimes, polarities and reflectivities of the detected reflections and said intrinsic attenuation of the sediment layer between pairs of adjacent reflections. A forward model describing the physical relationship between the material properties and the acoustic properties of seabed sediments is also disclosed.

Abstract: A method of analyzing an electromagnetic wavefield includes the steps of measuring the electric and magnetic fields at at least one receiver, formulating a respective spatial domain filter in respect of each of mutually orthogonal components of each of the electric and magnetic fields, and applying the filters to the measured acquired data to decompose the wavefield into upgoing and downgoing components.

Abstract: A method for generating an average gamma factor for recorded PS data and recorded PP data. The method includes mapping one or more arrival times of the recorded PS data onto one or more expected arrival times of the recorded PP data using an estimated average gamma factor, identifying one or more corresponding pairs of events in the recorded PS data and the recorded PP data using forward modeling, applying geophysical reasoning on the corresponding pairs of events and generating the average gamma factor.

Abstract: One embodiment of the present invention provides a system that removes noise from an image. During operation, the system first identifies blobs in the image, wherein a blob is a set of contiguous pixels which possibly represents a character or a portion of a character in the image. Next, the system analyzes the blobs to dynamically determine a “noise threshold” for the blobs. The system then removes blobs from the image which are below the noise threshold.

Abstract: A system includes an interface and a processor. The interface receives seismic datasets, which are associated with multiple firings of a set of at least one seismic source. Each dataset is acquired by seismic sensors during a different time period of a sequence of time periods that are limited by times at which the set of seismic source(s) are fired. The processor, for each of the firings of the set of seismic source(s), generates an associated shot record based on information contained at least two of the datasets.

Abstract: 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.

Abstract: A method for processing seismic data. The method may include splitting the seismic data into multiple datasets according to one or more offsets; determining a first shift amount in three or more dimensions of the seismic data between a dataset having a first offset and a dataset having a second offset, determining a second shift amount in the three or more dimensions between the dataset having the second offset and a dataset having a third offset, determining a cumulative shift amount based on a shift of the first shift amount and the second shift amount and determining a corrected dataset based on the dataset having the third offset and the cumulative shift amount.

Abstract: Method of processing seismic data corresponding to acquisitions carried out in a medium exhibiting azimuthal anisotropy, characterized in that for two sets of data corresponding, for one and the same seismic variable and for one and the same ground zone, to at least two different source/azimuth receiver pair sectors, an average between the data which correspond to the azimuth considered and data which correspond, for the same variable and the same ground zone, to a perpendicular azimuth sector is determined for each of the azimuths considered, and in that an estimate of the part common to the two sets thus obtained of averaged data is determined.

Abstract: Method for controlling the phase spectrum of seismic data to match assumptions inherent in subsequent processing steps. The source signature, after processing with the same initial processing steps used on the data, is used to design a phase control filter that shapes the seismic data to have a minimum phase spectrum or whatever other phase spectrum the subsequent processing algorithms may assume. The processed data is then filtered with a second phase-control filter, also designed using the parallel-processed signature, to shape the data to zero phase or whatever other phase may be desired for interpretation of the data.

Abstract: 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.

Abstract: A calculated vertical velocity sensor signal is determined from a recorded pressure sensor signal. A constructed vertical velocity sensor signal is determined as a linear combination of the calculated vertical velocity sensor signal and a recorded vertical velocity sensor signal in dual-sensor seismic streamer data, using a mixture coefficient as a proportionality constant. An upgoing pressure wavefield component is determined as one half of a difference of the recorded pressure sensor signal and the constructed vertical velocity sensor signal, as a function of the mixture coefficient. An error in the upgoing pressure wavefield component is determined by propagating errors in the recorded pressure sensor signal and constructed vertical velocity sensor signal terms. A value of the mixture coefficient is determined that minimizes the error in the upgoing pressure wavefield component.

Abstract: A wavelet-based method for improving the quality of seismic data utilizing the intercept determined by applying least squares regression to the wavelet transform of a seismic trace. The intercept is calculated for every time point of the wavelet transform for each seismic trace. The intercepts are then plotted versus time or depth. These plots are used in place of seismic traces themselves to create two dimensional and three dimensional seismic section images. In one embodiment, the real and imaginary portions of the selected wavelet transform are weighted to generate a finer representation of the intercept. In another embodiment, a minimum amplitude value is utilized to establish a noise floor, thus stabilizing the regression calculation. In yet another embodiment, a taper of the amplitude is applied to wavelet enhance the resolving power of the wavelet.

Abstract: Seismic data collected by a group of seismic receivers is received, and properties of coherent noise for plural modes of the coherent noise based on the received seismic data are computed to produce a model of the coherent noise for the plural modes. Using the model, the coherent noise is simulated to generate a synthetic noise.

Abstract: A method for acquiring and analyzing time-series data using singularities is described. This method allows for the analysis of data over a wide spectrum of frequencies. Once the data is acquired in an oil field, singularities of the data are extracted; and the extracted singularities are utilized to interpret the formation properties related to the data.

Abstract: A subterranean structure is characterized using composite seismic response data received from a plurality of sources. Phase encoding is applied to the data in which phase shifts are selected based on frequency variation of noise terms. The phase-encoded data is then migrated and a representation of the subterranean structure is produced according to the migrating.

Abstract: Systems and methods for monitoring time-dependant subsurface changes from imperfectly repeated data measurements.

Abstract: This invention provides a method for the quantitation and quality assurance of QPCR data. In particular, the invention provides a method for extracting data curves from a QPCR assay, estimating the shape and characteristics of an amplification curve and producing a quality score metric. The invention also provides a robust method for calculating a threshold cycle (CT) value and classifying the status of the QPCR results.

Abstract: Systems, program product, and methods of suppressing residual water bottom energy in seismic data, are provided. An example of a system, program product, and method can be applied to post-stack datasets and can combine multi-channel deconvolution with novel sorting keys to efficiently identify and suppress residual water bottom energy in common depth point (CDP) stacked seismic data, thereby increasing the resolving power of seismic data leading to an improved interpretation of seismic signals reflected from oil reservoirs.

Abstract: Seismic data may be imaged using or recognizing substantially only primary reflections. Imaging seismic data may include for example integrating a plurality of seismic data points that have substantially similar arrival directions, for example, to a modeled primary ray. Seismic data points may be imaged that for example substantially meet a set of predetermined conditions, for example, conditions substantially unique to primaries, which may include for example arrival direction and angle of reflection.

Abstract: An iterative process is described for obtaining a finite impulse filter to remove noise from seismic data through an iterative process with constraints on the filter applied in both, the original space-time and the transform frequency wave number at each iteration step.

Abstract: Method for survey design including configuring electrodes to reduce near-surface noise in the seismic response from an electroseismic survey of a subterranean formation. Different embodiments of the invention include (1) selective measurement of the surface noise to remove it from the data; (2) suppressing surface noise generation by reducing electric fields in the vicinity of some of the electrodes; (3) creating source signature differences between the near-surface seismic response and the deep response enabling the near surface response to be removed in data processing; (4) applying an external near-surface magnetic field to modulate the near-surface seismic response, enabling it to be removed in processing; and (5) constructing a partial Faraday cage to shield a near-surface region from fields generated by the electrodes.

Abstract: Correcting seismograms to compensate for absorption or dissipative effects that occur in the earth. In one implementation, a ratio of traveltime (t) to absorption parameter (Q) may be computed for each seismogram. The ratio may be referred to as R. Further, the ratio may be computed for a predetermined set of traveltimes. As a result, a system of linear equations may be generated, where each ratio is represented by a linear equation having a number of unknown components. The system of linear equations may then be solved for the unknown components. The solved components may then be recombined or added to generate an estimate of R. In one implementation, only a portion of the solved components may be added. The seismograms may then be corrected using the estimate of R. As such, the seismograms may be corrected for absorption effects in a surface consistent manner.

Abstract: A method determining a calibration filter to calibrate a first component of multi-component seismic data relative to a second component of the seismic data comprises determining the calibration filter from a portion of the seismic data that contains only events arising from critical refraction of seismic energy. The method is particularly suitable for long-off-set data, since the first arrival will be a critical refraction event and an automatic picking method may be used. The present invention also provides a wavenumber dependent calibration filter that is obtained from a calibration filter obtained from data in one offset range and another calibration filter obtained from data in another offset range.

Abstract: Noise may be filtered or attenuated from seismic data by building a four-dimensional volume using the acquired seismic data and then applying a random noise attenuation filter to the four-dimensional volume. The dimensions of the four-dimensional volume may include a trace number dimension, a time dimension, a shot number dimension, and a cable number dimension. The random noise attenuation filter may filter portions of the acquired seismic data if the seismic data is not correlated with respect to other seismic data in the four dimensional volume.

Abstract: A method of filtering seismic signals is described using the steps of obtaining the seismic signals generated by activating a seismic source and recording signals emanating from the source at one or more receivers; defining a source signature deconvolution filter to filter the seismic signal, wherein the filter is scaled by a frequency-dependent term based on an estimate of the signal-to-noise (S/N) based on the spectral power of a signal common to a suite of angle-dependent far-field signatures normalized by the total spectral power of the signatures within the angular suite and performing a source signature deconvolution using the source signature deconvolution filter.

Abstract: An eye opening measurement technique, that does not interrupt a receiver's normal operation, is used as a metric for optimizing any selected parameters of the receiver's operation. If eye opening size decreases, as a result of a change to a receiver parameter, the polarity for stepwise changes is reversed such that the next change is in the opposite direction. Other types of search procedures can be used. Eye opening size is the difference between the eye's upper and lower edges. Measurement of eye opening size is accomplished using a data and auxiliary slicer that find each “edge” of an eye opening based upon the slicers' level of agreement. Depending upon the level of agreement, and whether symbols of the upper or lower region of the eye are counted, the threshold of the auxiliary slicer can be adjusted in the direction necessary to converge on the eye edge sought.

Abstract: A method for modeling geological structures includes identifying fault planes in a geologic structure, and creating a set of substantially vertically oriented pillars along the fault plane. The pillar grids are then combined into a common three-dimensional grid pillar network, and a two-dimensional plane is defined that intersects the middle node of the pillars. Planes are identified that are oriented in the substantially horizontal direction and horizontal node points are created, and such a process is repeated for other node levels. A skeleton grid is then created by drawing a substantially vertically oriented pillar through each corresponding grid intersection, and then primary horizons as defined by interpretation of seismic data are inserted into the skeleton grid. And, a final scale resolution is created by dividing the spaces bounded between actual horizons and fault planes, and eventual actual part of the outer boundary into one or more horizontally oriented fine layers.

Abstract: A method of processing seismic data includes storing in a single file structure a first type of data representing an inline location, a second type of data representing a crossline location, and a third type of data representing at least one of a depth and time, said first, second and third type of data each being associated with a horizon of a poststack seismic trace at a location defined by said inline location and said crossline location; and storing in said single file structure at least a fourth type of data representing an attribute associated with said horizon of said poststack seismic trace at said location.

Abstract: A method for tracking a sinusoidal electromagnetic signal in noisy data using a Kalman filter or other tracking algorithm. The method is useful for controlled source electromagnetic surveying where longer source-receiver offsets can cause the source signal to decay significantly and be difficult to retrieve from magnetotelluric or other electromagnetic background.

Abstract: Implementations of various technologies for a method for processing seismic data. In one implementation, the method may include receiving a record of seismic data. The record of seismic data may have a plurality of attributes. A first seismic data process may be performed on the record of seismic data. The first seismic data process may generate a plurality of datasets. A selection of a portion of the plurality of attributes for ranking the datasets may be received. A quality score may be determined for each attribute of the portion of the plurality of attributes for each dataset. A ranking may be determined for each dataset based on the quality score.

Abstract: The force exerted by a reciprocating actuator is estimated as a weighted sum of three quantities: a reaction-mass acceleration, a baseplate acceleration, and a relative acceleration of the reaction-mass relative to the baseplate. In one embodiment, acceleration sensors measure the reaction-mass acceleration and the baseplate acceleration; and a displacement transducer measures a relative displacement of the reaction-mass relative to the baseplate. A double-differentiator generates the value of the relative acceleration from the second derivative of the relative displacement. In the sum, the relative acceleration is weighted by factor representative of the ratio of the difference between the masses of the reaction-mass and the baseplate to the sum of the masses of the reaction-mass and the baseplate.

Abstract: A method for determining impedance coefficients of a seismic trace comprises determining reflection coefficients of the seismic trace, for example using a sparse spike inversion, integrating the reflection coefficients with respect to time to obtain impedance coefficients, and filtering the impedance coefficients by applying a low-cut window filter. The window size and/or shape may be defined by a variable parameter which may be either specified by a user or optimized on the basis of a lateral variability parameter calculated for different values of the window parameter.

Abstract: 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.

Abstract: The disclosure describes a method and apparatus for effectively communicating data along an acoustic transmission path. The method comprises driving an acoustic transmitter to send a data signal along the acoustic transmission path, where the signal is distorted by ambient noise. The distorted signal is input to a spaced apart plurality of sensors so that consequent time-delayed signals provide reinforcement of the basic signal and attenuation of the ambient noise component when combined.

Abstract: A method for collecting data for a geographic database is disclosed. Speed and position data are collected using a plurality of mobile computing platforms moving in a geographic region. The speed and position data are analyzed to identify a location of a recurring delay point corresponding to a change in the speed. The geographic database is updated to indicate the location of the recurring delay point.

Abstract: Neural networks may be used to determine and predict formation dip angles and perform quality assurance assessments from data collected with a multi-component induction tool used for well logging. The neural networks make use of corrected, rotated and normalized data to provide the predictions and assessments. Synthetic data using various models is used to train the neural networks. The teachings herein provide for real-time determinations with a substantial degree of accuracy in the results.