Patent classifications
G01V2210/6169
MULTI-STACK (BROADBAND) WAVELET ESTIMATION METHOD
Computing device, computer instructions and method for estimating a broadband wavelet associated with a given seismic data set. The method includes receiving broadband seismic data; constructing and populating a misfit function; calculating the broadband wavelet based on the misfit function and the broadband seismic data; and estimating physical reservoir properties of a surveyed subsurface based on the broadband wavelet. The broadband wavelet is constrained, through the misfit function, by (1) an amplitude only long wavelet, and (2) an amplitude and phase short wavelet. The amplitude and phase short wavelet is shorter in time than the amplitude only long wavelet.
SEISMIC PORE-PRESSURE PREDICTION USING PRESTACK SEISMIC INVERSION
A method of predicting pore pressure based on seismic data can include obtaining seismic inversion data based in part on seismic data collected from a formation. The method also includes calculating a pore-pressure transform, wherein the pore-pressure transform comprises parameters derived using measured pore pressure data, upscaled sonic logs, and density logs, wherein the pore-pressure transform comprises an objective function to reduce unphysical variations in predicted pore pressure corresponding to depth. Additionally, the method can include adjusting the pore-pressure transform for sampling bias caused by pore pressure measurements being restricted to a plurality of lithologies by accounting for a difference between upscaled seismic velocities and average sonic velocities within each of the lithologies. Furthermore, the method can include generating pore pressure prediction values based on the pore-pressure transform for the lithologies and the seismic inversion data, and modifying a seismic model based on the generated pore pressure prediction values.
PORE PRESSURE IN UNCONVENTIONAL FORMATIONS
Disclosed are methods, systems, and computer-readable medium to perform operations including: receiving a density log and a compressional slowness log measured in a wellbore located in a formation; generating, based on at least one of the density log or the compressional slowness log, a reference compressional slowness log; determining, for an interval in the formation, a relationship between the compressional slowness log and the reference compressional slowness log; generating, based on the relationship and known pressure information in the interval, a pressure scale for the formation; and using the pressure scale to calculate pressure in the interval.
METHODS AND DEVICES CORRELATING WELL-LOGS TO CUTTINGS LITHOLOGIES FOR SYNTHETIC CORE GENERATION
An exploration method starts from cuttings associated with sampling intervals and well data for a well in a subsurface formation. The cuttings are prepared and analyzed to extract textural and chemical/mineralogical data for plural fragments in each sample that is made of the cuttings in one sampling interval. The method then includes matching lithotypes of rock defined according to the textural and chemical/mineralogical data for each fragment with segments of the well data in the corresponding sampling interval to obtain correspondences between the lithotypes and depth ranges. The correspondences between the lithotypes and the depth ranges may be used as constraints for seismic data inversion.
SYSTEM AND METHOD FOR GENERATING SLOWNESS LOGS IN THINLY LAMINATED FORMATIONS
A method, computer program product, and computing system for generating high resolution slowness logs. The method computer program product, and computing system includes receiving a plurality of sonic logs from at least one sensor array and generating at least one high-resolution slowness log from the plurality of sonic logs based upon, at least in part, monopole and dipole data from the plurality of sonic logs.
DETERMINING A SEISMIC QUALITY FACTOR FOR SUBSURFACE FORMATIONS FROM A SEISMIC SOURCE TO A FIRST VSP DOWNHOLE RECEIVER
A method or system is configured for determining a seismic attenuation quality factor Q for intervals of subsurface formations by performing actions including receiving vertical seismic profile traces. The actions include filtering the vertical seismic profile traces with an inverse impulse response of a downhole receiver. The actions include transforming the vertical seismic profile data from the particle motion measured by the downhole receiver to the far-field particle motions represented by the source wavelet. The actions include determining a ratio of the spectral amplitudes of the direct arrival event of the transformed vertical seismic profile data and the source Klauder wavelet. A quality factor Q is generated representing an attenuation of the seismic signal between the source at ground level surface and the downhole receiver.
Distributed Acoustic Sensing: Locating of Microseismic Events Using Travel Time Information with Heterogeneous Anisotropic Velocity Model
A fracture mapping system for use in hydraulic fracturing operations utilizing non-directionally sensitive fiber optic cable, based on distributed acoustic sensing, deployed in an observation well to detect microseismic events and to determine microseismic event locations in 3D space during the hydraulic fracturing operation. The system may include a weighted probability density function to improve the resolution of the microseismic event on the fiber optic cable.
METHOD AND APPARATUS FOR ESTIMATING S-WAVE VELOCITIES BY LEARNING WELL LOGS
Disclosed are a method and apparatus for estimating S-wave velocities by learning well logs, whereby the method includes a model formation step of forming an S-wave estimation model to output S-wave velocities corresponding to measured depth when the well logs are input based on train data sets including train data having values of multiple factors included in the well logs, the values being arranged corresponding to measured depth, and label data having S-wave velocities corresponding to measured depth as answers, and an S-wave velocity estimation step of inputting unseen data having values of multiple factors included in well logs acquired from a well at which S-wave velocities are to be estimated, the values being arranged corresponding to measured depth, to the S-wave estimation model to estimate S-wave velocities corresponding to measured depth.
PHYSICS-DRIVEN DEEP LEARNING INVERSION COUPLED TO FLUID FLOW SIMULATORS
A method for a physics-driven deep learning-based inversion coupled to fluid flow simulators may include obtaining measured data for a subsurface region, obtaining prior subsurface data for the subsurface region, and obtaining a physics-driven standard regularized joint inversion for at least two model parameters. The method may further include obtaining a case-based deep learning inversion characterized by a contracting path and an expansive path. The method may further include forming the physics-driven deep learning inversion with the physics-driven standard regularized joint inversion, the case-based deep learning inversion, and a coupling operator based on a penalty function. The method may further include forming a feedback loop between the physics-driven standard regularized joint inversion and the case-based deep learning inversion for re-training the case-based deep learning inversion. The method may further include generating an inversion solution for reservoir monitoring.
System and method for spatially imaging and characterizing properties of rock formations using specular and non-specular beamforming
A method for imaging non-specular seismic events as well as correlating non-specular events with physically measurable quantites in a volume of Earth's subsurface. Includes entering as input to a computer signals detected by a plurality of seismic sensors disposed above and/or within the volume in response to actuation of at least one seismic energy source above and/or within the volume. Parameter analysis is performed to populate the initial model with point-wise, best-fit wavefront travel-time approximations. Imaging is performed to obtain undifferentiated specular and non-specular representations of the volume. Specular boundaries are mapped using the imaged volume and using the boundaries to form a model of specular components of the volume. Beamforming is used to characterize seismic attributes associated with specular and non-specular reflections as separate and differentiated data sets.