CN-121995519-A - Crack characteristic inversion method, system, storage medium and electronic equipment

CN121995519ACN 121995519 ACN121995519 ACN 121995519ACN-121995519-A

Abstract

The invention belongs to the technical field of geophysics and provides a fracture characteristic inversion method, a system, a storage medium and electronic equipment, wherein the method comprises the steps of simulating a hydrocarbon fluid filling process based on a digital core sample, and acquiring distribution conditions and saturation of the hydrocarbon fluid in the filling process; the method comprises the steps of constructing crack models with different inclination angles based on digital core samples, respectively simulating hydrocarbon fluid filling processes of the crack models by combining distribution conditions and saturation of hydrocarbon fluid in the filling processes, obtaining acoustic parameters and electrical parameters of the hydrocarbon fluid in the filling processes of the crack models, generating inversion models according to the acoustic parameters and the electrical parameters corresponding to all the crack models, inverting characteristics of actual cracks and physical parameters of a reservoir based on the inversion models, and obtaining a crack characteristic inversion result. And taking the digital core sample as input, establishing an acoustic and electric inversion template aiming at a heterogeneous medium of hydrocarbon-containing fluid, and accurately inverting the fracture characteristics and reservoir physical parameters.

Inventors

YANG ZHIFANG
GUO CHEN
LI XIAOMING
Yan xinfei
LING BOWEN
ZOU TIAN
ZHANG JIN

Assignees

中国石油天然气集团有限公司

Dates

Publication Date: 20260508
Application Date: 20241106

Claims (10)

1. A fracture characterization inversion method, the method comprising: simulating a filling process of the hydrocarbon fluid based on the digital core sample, and acquiring the distribution condition and the saturation of the hydrocarbon fluid in the filling process; based on the digital core sample, constructing crack models with different inclination angles, and respectively simulating hydrocarbon fluid filling processes of the crack models by combining the distribution condition and the saturation of hydrocarbon fluid in the filling process; Respectively acquiring acoustic parameters and electrical parameters in the hydrocarbon fluid filling process of each crack model, establishing an anisotropic acoustic-electric joint graph plate according to the acoustic parameters and the electrical parameters corresponding to all the crack models, and generating an inversion model; and based on the inversion model, the fracture characteristics and the reservoir physical parameters are inverted by combining the acoustic parameters and the electrical parameters of the actual core, and the fracture characteristic inversion result is obtained.
2. The method of claim 1, wherein simulating the hydrocarbon fluid filling process based on the digital core sample to obtain the distribution and saturation of the hydrocarbon fluid during the filling process comprises: generating a core pore model, a dominant channel model and an unoccupied channel model based on the digital core sample, wherein the core pore model comprises natural fractures, the dominant channel model comprises fractures extending in a direction away from hydrocarbon fluid, and the unoccupied channel model comprises fractures extending in the direction of hydrocarbon fluid; simulating a hydrocarbon fluid filling process of the core pore model, a hydrocarbon fluid filling process of the dominant channel model, and a hydrocarbon fluid filling process of the non-dominant channel model respectively; and obtaining the distribution condition and the saturation of the hydrocarbon fluid in the filling process of the hydrocarbon fluid in the model of the non-dominant channel.
3. The method of claim 1, wherein constructing fracture models of different inclination angles based on the digital core sample, and simulating hydrocarbon fluid filling processes of each fracture model respectively in combination with distribution and saturation of hydrocarbon fluid during filling processes, comprises: Based on the digital core sample, respectively constructing a crack model without an inclination angle, a crack model with an inclination angle of 30 degrees, a crack model with an inclination angle of 45 degrees, a crack model with an inclination angle of 60 degrees and a crack model with an inclination angle of 90 degrees, wherein each crack model is a three-dimensional model; and respectively simulating the hydrocarbon fluid filling process of the crack model without the inclination angle, the crack model with the inclination angle of 30 degrees, the crack model with the inclination angle of 45 degrees, the crack model with the inclination angle of 60 degrees and the crack model with the inclination angle of 90 degrees by combining the distribution condition and the saturation degree of the hydrocarbon fluid in the filling process.
4. The method of claim 1, wherein the obtaining acoustic parameters and electrical parameters of each fracture model during the hydrocarbon fluid filling process, and establishing an anisotropic acoustic-electric joint plate according to the acoustic parameters and electrical parameters corresponding to all fracture models, and generating an inversion model, comprises: Acquiring a longitudinal wave velocity change curve, a transverse wave velocity change curve and a resistivity change curve of the fracture model in the hydrocarbon fluid filling process; Generating an acoustic wave velocity-saturation line graph according to the longitudinal wave velocity change curve and the transverse wave velocity change curve corresponding to the crack model in the hydrocarbon fluid filling process and combining the distribution condition and the saturation of the hydrocarbon fluid in the filling process; And establishing the anisotropic acoustic-electric joint graph plate according to the corresponding longitudinal wave velocity change curve, the corresponding transverse wave velocity change curve, the corresponding acoustic wave velocity-saturation line graph and the corresponding resistivity change curve in the hydrocarbon fluid filling process of all the fracture models, and generating the inversion model.
5. The method of claim 4, wherein the acquiring the fracture model during hydrocarbon fluid filling, the longitudinal wave velocity profile and the transverse wave velocity profile, the resistivity profile, comprises: in the process of simulating hydrocarbon fluid injection by the fracture model, applying acoustic wave excitation at the boundary of the fracture model, recording a longitudinal wave waveform and a transverse wave waveform, calculating the longitudinal wave velocity and the transverse wave velocity, and generating a longitudinal wave velocity change curve and a transverse wave velocity change curve; in the process of simulating hydrocarbon fluid injection, the crack model applies electrical excitation to the boundary of the crack model, acquires electric field intensity and current density, determines a resistivity tensor value according to the electric field intensity and the current density, and generates the resistivity change curve.
6. The method of claim 4, wherein the creating an anisotropic acoustic-electric joint map and generating an inversion model from the corresponding longitudinal wave velocity profile, transverse wave velocity profile, and acoustic velocity-saturation line graph, and resistivity profile of all fracture models during hydrocarbon fluid filling comprises: According to the corresponding resistivity change curves of all the fracture models in the hydrocarbon fluid filling process, and by combining the distribution condition and saturation of the hydrocarbon fluid in the filling process, a resistivity-fracture inclination angle-saturation line graph is generated; And in the hydrocarbon fluid filling process by combining all the fracture models, establishing an anisotropic acoustic-electric joint graph plate and generating an inversion model by combining a corresponding longitudinal wave velocity change curve, a corresponding transverse wave velocity change curve, a corresponding resistivity change curve, a corresponding acoustic wave velocity-saturation line graph and a corresponding resistivity-fracture inclination angle-saturation line graph.
7. The method of claim 5, wherein three electrical stimuli are applied to different directions at the boundaries of the fracture model.
8. The fracture characteristic inversion system is characterized by comprising a first simulated filling module, a fracture simulated filling module, an inversion model generation module and an inversion module; The first simulation filling module is used for simulating the filling process of the hydrocarbon fluid based on the digital core sample and obtaining the distribution condition and the saturation of the hydrocarbon fluid in the filling process; the crack simulation filling module is used for constructing crack models with different inclination angles based on the digital core sample, and respectively simulating hydrocarbon fluid filling processes of the crack models by combining the distribution condition and the saturation of hydrocarbon fluid in the filling process; The inversion model generation module is used for respectively acquiring acoustic parameters and electrical parameters in the hydrocarbon fluid filling process of each crack model, establishing an anisotropic acoustic-electric joint graph plate according to the acoustic parameters and the electrical parameters corresponding to all the crack models, and generating an inversion model; the inversion module is used for inverting the fracture characteristics and the reservoir physical parameters based on the inversion model by combining the acoustic parameters and the electrical parameters of the actual core, and obtaining fracture characteristic inversion results.
9. A computer-readable storage medium storing one or more programs, characterized in that, The fracture characterization inversion method of any one of claims 1-7 may be implemented when the one or more programs are executed.
10. An electronic device comprising a processor, a communication interface, the computer-readable storage medium of claim 9, and a communication bus, wherein the processor, the communication interface, and the computer-readable storage medium communicate with each other over the communication bus; It is characterized in that the method comprises the steps of, The processor is configured to execute a program stored in a computer-readable storage medium.

Description

Crack characteristic inversion method, system, storage medium and electronic equipment Technical Field The disclosure belongs to the technical field of geophysics, and particularly relates to a fracture characteristic inversion method, a fracture characteristic inversion system, a storage medium and electronic equipment. Background Fractures are prevalent in unconventional energy reservoirs that provide vital pathways for the storage and circulation of oil and gas. Therefore, quantitative prediction and accurate evaluation of reservoir fracture parameters have a vital role in the exploration and development of unconventional hydrocarbon reservoirs. The presence of the fracture significantly increases the permeation and diffusion efficiency of the hydrocarbon fluid, allowing it to more rapidly enter and fill the reservoir. However, in areas without or with less fracture distribution, the fluid filling process is slow, and these complex geological features often lead to uneven distribution of the fluid in the reservoir, and even local blockage in certain areas, further increasing the difficulty of oil and gas exploration and development. In the exploration and development process of oil and gas resources, key parameters such as crack characteristics and the like are deeply understood and accurately predicted, and the method has important significance in optimizing exploitation strategies and improving oil and gas recovery ratio. The distribution of hydrocarbon fluids has a significant effect on the acousto-electric properties of the rock, firstly, the distribution of hydrocarbon fluids has a great effect on the acoustic properties of the rock, the density and compressibility of hydrocarbon fluids are low, the sound velocity of the rock is changed when hydrocarbon fluids exist, and the existence of hydrocarbon fluids has an effect on the propagation and attenuation of sound waves, so that the effect of hydrocarbon fluids needs to be considered in elastic wave exploration to accurately identify underground structures. In terms of electrical properties, the presence of hydrocarbon fluids also affects the resistivity and conductivity of the rock, and as hydrocarbon fluids are often poor conductors of electricity, the presence of hydrocarbon fluids reduces the resistivity of the rock and increases the conductivity of the rock, which is particularly important in oil and gas exploration because changes in resistivity are one of the important indicators for identifying hydrocarbon reservoirs. The acoustic-electrical inversion of the core is to obtain physical parameters of rock by measuring acoustic and electrical properties of a core sample, wherein the physical parameters include but are not limited to acoustic velocity, resistivity and the like, and the physical parameter model of the core is obtained by inversion through a mathematical method. The existing inversion model assumes that the medium is uniform, and has lower inversion accuracy for heterogeneous medium with complex geological structure and reservoir medium filled with hydrocarbon. Most of the existing inversion models assume that the medium is isotropic, and the influence of the anisotropic medium cannot be considered. In the research work of an anisotropic model, the electromagnetic geophysical team of Changan university carries out tensor correction on classical models such as Archie theorem and the like aiming at the electric anisotropy of fractured rock, and predicts fracture morphology and distribution by combining with mechanical tensor, and the artificial sandstone containing directionally arranged cracks is subjected to experiment and theoretical research by using a sound-electricity combination method in the research result of Han Tong city of China petroleum university (Huadong) and the correlation of longitudinal wave speeds and electric conductivities in different directions is analyzed. In summary, the prior art does not have a method for measuring an anisotropic medium to generate an inversion model during hydrocarbon fluid filling. Disclosure of Invention In order to solve the problems, the disclosure provides a fracture characteristic inversion method, a system, a storage medium and electronic equipment, which adopt a fracture model based on a digital core sample to generate different inclination angles, simulate the filling flow of hydrocarbon fluid, acquire electrical parameters and acoustic parameters in the filling process, and generate a graph plate so as to accurately invert the fracture characteristics and reservoir physical parameters of an actual core sample. The invention is realized by the following technical scheme: in a first aspect, an embodiment of the present disclosure provides a fracture feature inversion method, the method including: simulating a filling process of the hydrocarbon fluid based on the digital core sample, and acquiring the distribution condition and the saturation of the hydrocarbon fluid in the fillin