Patent classifications
G01V2210/3248
ENHANCING SEISMIC IMAGES
A method of enhancing seismic images includes receiving a seismic gather. The seismic gather includes a plurality of seismic traces. A feature trace is generated based on the plurality of seismic traces in the seismic gather. For each of the plurality of seismic traces in the seismic gather, a correlation trace is generated based on that seismic trace and the feature trace, the correlation trace is modified using an activation function, and an enhanced trace is generated by multiplying that seismic trace with the modified correlation trace.
Noise removal for distributed acoustic sensing data
An example system for noise removal in distributed acoustic sensing data may include a distributed acoustic sensing (DAS) data collection system and an information handling system coupled thereto. The information handling system may receive seismic information from the DAS data collection system. The seismic information may include seismic traces associated with a plurality of depths in the wellbore. The information handling system may also generate a noise pilot trace by stacking one or more of the seismic traces, and subtract the noise pilot trace from the seismic information received from the DAS data collection system.
Device and method for deblending simultaneous shooting data using an iterative approach
A device, medium and method for deblending seismic data associated with a subsurface of the earth. The method includes a step of receiving seismic data S recorded with one or more seismic receivers, wherein the seismic data S includes shot recordings generated by first and second source arrays that are simultaneously actuated; a step of detecting incoherent energy of the seismic data S using a median filter; a step of replacing incoherent parts of the seismic data with a projection filter to obtain deblended data for one of the two or more source arrays; and a step of generating in a computing device an image of the subsurface based on the deblended data.
Method of removing incoherent noise
Noise is removed from a data set by performing an integral transform operation that converts instances of noise into identifiable artifacts in the transformed data set. A model of the artifacts is constructed by creating a full-domain or partial-domain noise model and performing the same integral transform operation on the noise model. The resulting transformation of the noise model is adaptively subtracted from the transformed data set to remove the noise. The adaptive subtraction may employ a least-square error filter.
Systems and methods for multi-volume directional de-noising
Systems and methods are provided for directional de-noising on seismic data recorded byseismic receivers. A method includes: receiving a seismic dataset, wherein the seismic dataset includes a model dataset and an input dataset to filter; decomposing the model dataset into a plurality of model directions, identifying which of the model directions to keep; and mapping the input dataset along the identified model directions resulting in a filtered output.
Noise model estimation in multimeasurement data
Various implementations described herein are directed to methods for processing seismic data, including estimating a spectral noise power of multi-measurement seismic data received from a multi-dimensional seismic sensor array having multiple seismic sensors. The methods may include receiving a shot record of multi-measurement seismic data in time-domain, partitioning the shot record into overlapping time-space windows, and computing a frequency-domain spectrum for each time-space window. The methods may include computing a signal presence probability for each time-space window using the frequency-domain spectrum and prior probabilities of signal presence and absence for each time-space window. The methods may include iteratively updating a collective spectral noise power by recursively estimating the spectral noise power of a current time-space window based on the frequency spectrum for the current time-space window, the signal presence probability computed for the current time-space window, and a previously estimated spectral noise power of a previous time-space window.
Attenuation of interface waves using single component seismic data
Systems and methods for filtering interface waves from single component seismic data are disclosed. In one embodiment, a method of filtering seismic data includes comparing amplitude coefficients of a matrix storing the seismic data in a time-frequency domain against an amplitude threshold, and comparing frequencies of the matrix against a maximum expected frequency of noise. The method further includes, for each amplitude coefficient having less than the amplitude threshold and an associated frequency less than the maximum expected frequency of noise, scaling the amplitude coefficient to reduce its value. The method also includes performing an inverse time-frequency transformation on the matrix to generate a noise model in a time domain, and subtracting the noise model from the seismic data in the time domain to generate filtered seismic data.
METHOD FOR RANDOM NOISE REDUCTION FROM MRS OSCILLATING SIGNAL USING JOINT ALGORITHMS OF EMD AND TFPF
The instant invention relates to a method for noise reduction from a magnetic resonance sounding (MRS) oscillating signal, and more particularly, to a data processing method for reducing random noise contained in MRS oscillating signal based on joint algorithm principles of EMD and TFPF. A MRS oscillating signal is decomposed into different eigen-mode components by using decomposition characteristic of EMD algorithm; then a signal-dominated eigen-mode component is encoded as an instantaneous frequency of an analytical signal of unit amplitude using TFPF algorithm; and random noise is suppressed with the characteristics that the time-frequency distribution of the analytical signal is concentrated along with the instantaneous frequency. The method requires fewer filtering constraints and is simple to operate without need of designing a filtering interval in the time-frequency domain, and has good adaptability to the MRS oscillating signal with a low signal-noise-ratio.
Land Seismic Sensor Spread with Adjacent Multicomponent Seismic Sensor Pairs on Average at Least Twenty Meters Apart
A system and method for multicomponent noise attenuation of a seismic wavefield is provided. Embodiments may include receiving, at one or more computing devices, seismic data associated with a seismic wavefield over at least one channel of a plurality of channels from one or more seismic sensor stations. Embodiments may further include identifying a noise component on the at least one channel of the plurality of channels and attenuating the noise component on the at least one channel of the plurality of channels based upon, at least in part, the seismic data received from the one or more seismic sensor stations.
ANISOTROPIC NMO CORRECTION AND ITS APPLICATION TO ATTENUATE NOISES IN VSP DATA
A method for performing a formation-related operation based on corrected vertical seismic profile (VSP) data of an earth formation includes performing a VSP survey and applying a normal moveout (NMO) correction equation to the survey data that is a function of source offset to wellhead. The method also includes solving the NMO correction equation using a simulated annealing algorithm having an object function that is a coherence coefficient of semblance analysis of an NMO corrected reflection event within a time window to provide NMO corrected data. The method further includes performing the formation-related operation at at least one of a location, a depth and a depth interval based on the VSP NMO corrected data.