42 results about "Petrophysics" patented technology

A method of characterizing a borehole traversing an earth formation including (a) obtaining an array of data from a formation characterization tool, wherein the data describes a section of the borehole; (b) computing at least one spatial characteristic describing the relative position of pairs of data; (c) assigning said pairs of data to bins based on the spatial characteristic, wherein the size of the bins are selected based on the tool; (d) transforming the data to petrophysical properties of the borehole; (e) calculating the variance of each bin; (f) developing a model of the variances; (g) determining at least one geostatistical parameter using the model; and (h) upscaling the geostatistical parameters to characterize a region of said earth formation. The method may further include generating a heterogeneity index log using the geostatistical model parameters. The method may be implemented using a computer program product for processing and interpreting borehole data.

The disclosed embodiments include a system and method for performing a simulation to seismic process. In one embodiment, the system is configured to perform operations comprising constructing a petrophysical realization and selecting a candidate model for fluid flow simulation using the petrophysical realization. Empirical petrofacies definitions is applied on the selected candidate model and assigning relative permeability at each node of the petrofacies definitions of the selected candidate model. The operations performs flow simulation on selected candidate model and performs analysis on the results of the simulation on selected candidate model to verify rock type flow units. The dynamic and static simulation results are synthesized such that the combined data yield a measurable rock property that may be compared to seismic properties and used to calibrate subsequent iterations of the static earth model. The continued iteration of the workflow may then be undertaken with the updated/refined earth model.

Disclosed are various embodiments of a workflow or method for petrophysical rock typing of carbonates in an oil or gas reservoir or field comprising determining a Data Scenario (DS) for the reservoir or field, determining a plurality of Depositional Rock Types (DRTs) for the reservoir or field, determining a Digenetic Modification (DM) from a plurality of diagenetic modifiers or primary textures associated with the plurality of DRTs, selecting a Reservoir Type (RT) corresponding to the plurality of DRTs,determining at least one pore type, and determining, on the basis of the plurality of DRTs, the Diagenetic Modification (DM), and the at least one pore type, a plurality of Petrophysical Rock Types (PRTs) associated with the RT.

The invention provides a method for calculating shear wave velocity of a sandstone formation, and belongs to the field of rock physics and geophysical logging. The method comprises the following steps: (1) inputting an actually-measured longitudinal wave velocity Vp, density, porosity phi and a shale content Vsh curve of the sandstone formation, and setting an initial value and an interval of a consolidation coefficient c; (2) calculating a dry rock elastic modulus; (3) calculating a saturated rock elastic modulus, and calculating to obtain a calculated longitudinal wave velocity; (4) establishing an error function between the actually-measured longitudinal wave velocity Vp and the calculated longitudinal wave velocity; (5) within the value range of the consolidation coefficient c, changing the value of the consolidation coefficient c by using the interval, repeating the step (2) to the step (4) once when the changing is implemented every time to obtain the error function corresponding to each new consolidation coefficient c, comparing the error functions corresponding to all the consolidation coefficients c to find a consolidation coefficient c' which enables the error function to be minimum, and calculating the obtained shear wave velocity, namely the solved shear wave velocity, by virtue of the consolidation coefficient c' which enables the error function to be minimum.

The invention provides a rock compressibility-based carbonatite stratum pore pressure calculating method. The method comprises, according to mechanical theories on rock porous elasticity, analyzing the constitutive relation between rock compressibility and pore pressure as well as effective stress, and combining the Biot-Willis effective stress las to establish a carbonatite pore pressure predicting quantitative model for representing the relation between pore pressure and rock compressibility; performing a large amount of lithostratigraphic compressibility testing and data simulation, according to a fit quantitative relation between lithostratigraphic compressibility and effective stress as well as porosity, combining with carbonatite petrophysical simulation data to perform examination analysis of the pore pressure predicting quantitative model. Actual measurement shows that the pore pressure is high in correlation with key parameters in the pore pressure predicting quantitative model. From the perspective of petrophysics and based on the rock compressibility, the rock compressibility-based carbonatite stratum pore pressure calculating method theoretically establishes the quantitative model reflecting the pore pressure-rock compressibility constitutive relation and reduces influence of subjective cognition on pore pressure prediction.

The invention belongs to the technical field of petrophysics, and discloses a quantitative rock Biot coefficient calculation method considering multiple influence factors. The method comprises the steps that according to a conventional logging curve, determining a saturated rock bulk modulus and a pore mixed fluid equivalent bulk modulus under the corresponding depth of the logging point; the rockmatrix mineral bulk modulus corresponding to a logging point is determined by utilizing a self-adaptive matrix mineral modulus inversion theory, then comprehensive pore structure parameters representing a rock pore structure are calculated, and finally a quantitative rock Biot coefficient considering multiple influence factors is calculated. According to the Biot coefficient expression provided by the invention, the accuracy of estimating the Biot coefficient is improved, lithology limitation is avoided, and the universality of the calculation expression is improved.

The invention relates to a device and a method for measuring ground stress by using a core of an oil well. According to the technical scheme, an adjustable screw seat is arranged on the bottom of an experimental flat plate; a leveller, a laser transmitter, a light filter, a single-slit structure, a double-slit structure, a light shading barrel, a light screen and a micrometering eyepiece are sequentially arranged on the upper portion of the experimental flat plate; the leveller detects whether the experimental flat plate is horizontal or not through air bubbles in the leveller; the laser transmitter transmits monochromatic light with the wavelength of lambda; red light with the long wavelength is used; the single-slit structure is used for forming a line light source; and the micrometering eyepiece is used for measuring distances among a plurality of bright rays. The device for measuring the ground stress by using the core of the oil well has the advantages that the device is reasonable in design, simple in structure, easy to operate, easy to machine and manufacture, convenient to carry and low in cost and can measure strain of rock accurately, the magnitude of the ground stress can be determined through petrophysics parameters, and the device has an important guidance significance on high-efficiency development of an oilfield. Moreover, the device is convenient to carry and high in practicality, and can be used in a drill core store of the oilfield.

The invention relates to the technical field of petrophysics, in particular to a rock acoustic characteristic analysis method based on a digital rock core. The invention discloses a digital rock coreacoustic characteristic analysis method at different temperatures. The method comprises the following steps: A, constructing a multi-component three-dimensional digital rock core; B, calculating the bulk modulus and shear modulus of each component in the digital rock core at different temperatures; and C, calculating the stress-strain of the digital rock core by taking the result obtained in the step B as an input parameter, and obtaining the elastic modulus and the sound wave speed through the stress-strain. According to the invention, the construction of the high-resolution digital rock coreis realized, the relationship between the elasticity modulus and the temperature is constructed, and a digital rock core acoustic parameter simulation method at different temperatures is developed. By simulating the elasticity modulus and the sound wave speed of the rock core at different temperatures, the change rule of the temperature on the acoustic characteristics and the electrical characteristics of the rock is analyzed.

The invention discloses an anisotropic petrophysical calibration method based on a shale crystal geometrical factor orientation function. The core of the method is to use multiple anisotropic petrophysical models in combination of the crystal geometrical factor function. The method, based on multiple disciplines such as petrophysics, crystallography, mathematical modeling and like, converts well logging and core data to P-wave and S-wave velocity models and solves the problem of simulation of equivalent velocities in underground anisotropic media.

The invention relates to an examination success rate prediction device and method, a readable medium and electronic equipment. According to the technical scheme provided by the embodiment of the invention, based on the upper and lower limit theory of petrophysics, the score of the target part of each single subject is taken as the score under the relatively easy condition, and each upper limit index of the single subject is obtained by combining the total score of the target part and the percentage of each recording line; the method also includes taking the total score of the single family obtained by the shortened time simulation test as a score under a relatively difficult condition, and obtaining each lower limit index of the single family in combination with the total score of the single family and the percentage of each admission line; and obtaining the examination success rate of the single family based on the average value of each upper limit index and each lower limit index. Therefore, the technical scheme provided by the embodiment of the invention can automatically calculate the single-subject examination success rate, and has the advantages of simplicity and rapidness.

The invention provides a method and a system for improving logging shear wave velocity prediction precision, and belongs to the technical field of petrophysics and geophysical logging. The method comprises the steps that the regression relation between pore structure parameters of characteristic wells in a work area and the porosity and the shale content is counted, and the transverse wave speed of a to-be-predicted well in the work area is predicted through the regression relation, wherein the characteristic well is a well logging with transverse wave well logging information in the work area, and the to-be-predicted well is a well logging without transverse wave well logging information in the work area, namely a well logging needing to predict the transverse wave speed. According to themethod, rock pore structure parameters are introduced into logging shear wave velocity prediction, so that the logging shear wave velocity prediction precision is improved.