Fracture-vug type medium permeability calculation method and system based on fractal geometric dimension

Abstract

The invention relates to a fracture-vug type medium permeability calculation method and system based on fractal geometric dimensions. The method comprises the following steps: constructing a fracture-vug type medium model of a fracture-vug type porous medium sample; calculating flow parameters of the fracture-vug type porous medium sample according to the fracture-vug type medium model on the basis of a fractal theory; the flow parameters comprise the cross sectional area, the length and the total flow of the fracture-cavity type porous medium sample; and substituting the flow parameters into a flow equation of the fracture-vug type porous medium sample, and calculating the permeability of the fracture-vug type porous medium sample. The method comprises the following steps: firstly, constructing a fracture-vug type medium model, then loading the fracture-vug type medium model to different degrees according to the property of a fractal structure of a fracture-vug type oil reservoir and based on a fractal theory, calculating flow parameters under different stresses, and further determining the permeability under different stresses. According to the method, under the condition of considering the flow characteristics and fractal characteristics of the fracture-vug type medium, the permeability of the fracture-vug type medium is accurately predicted.

Description

technical field [0001] The invention relates to the technical field of oil reservoir detection, in particular to a method and system for calculating the permeability of fracture-cavity media based on fractal geometric dimensions. Background technique [0002] With the continuous consumption of fossil energy, the degree of exploration and development of petroleum resources has been deepened, and the types of newly discovered oil and gas reservoirs have become more and more complex in recent years, and fractured-vuggy carbonate reservoirs are one of them. Due to the comprehensive influence of rock structure, diagenetic epigenesis, structural fracture, and dissolution on the reservoir space, the reservoir structure of carbonate reservoirs is very complex, with multi-scale characteristics in space and time, resulting in It is quite difficult to accurately calculate the permeability of fracture-cavity reservoirs. Quantitative calculation and prediction of carbonate reservoir per...

AI Technical Summary

Problems solved by technology

At present, there are mainly two methods for simulating fractures in fractured-cavity reservoirs. One is the equivalent multi-media method, which is only suitable for network-shaped and uniformly distributed fractures, and cannot accurately simulate the flow of large fractures; the other is the discrete fracture network. method, this method cannot consider the simultaneous existence of multi-scale fractures and the model has a huge amount of calculation

And the numerical method requires tedious calculations, which limits its ability to analyze the stress sensitivity

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