A method for calculating sandstone permeability based on microscopic image processing

Abstract

The invention discloses a method for calculating the permeability of sandstone based on microscopic image processing. After the pore network image; the surface porosity of the sandstone microscopic image is determined according to the binarized pore network image; the particle diameter is determined according to the pore network image after pore throat enhancement; the pore curvature is determined according to the pore network image after pore throat enhancement; The permeability of sandstone is obtained by calculating the surface porosity, particle diameter and pore tortuosity. Aiming at the situation that it is difficult to obtain a large number of plunger cores, the invention only extracts the microscopic parameters of sandstone and calculates the permeability of sandstone through image processing through easily obtained rock microphotographs taken by small fragmented cores, so as to make up for the lack of permeability data. , to better guide the exploration and development of sandstone oil and gas reservoirs.

Description

technical field [0001] The invention relates to a sandstone permeability calculation method based on microscopic image processing, and belongs to the technical field of oil and natural gas exploration and development. Background technique [0002] Permeability refers to the ability of a rock to allow fluid to pass through under a certain pressure difference. It is a parameter that characterizes the ability of the rock itself to conduct liquids. This parameter is very important for the evaluation of oil and gas reservoirs. At present, there are two main types of commonly used methods for rock permeability evaluation: the first type is direct laboratory measurement, that is, the permeability of plunger cores is measured by a permeability meter. The advantage of this method is high accuracy, but requires a large number of columns. The plug core is measured. The second type is logging calculation and acquisition. According to the different logging methods used, it can be divide...

AI Technical Summary

Problems solved by technology

At present, there are two main types of commonly used methods for evaluating rock permeability: the first is direct laboratory measurement, that is, using a permeability meter to measure the permeability of a plunger core. This method has the advantage of high accuracy, but requires a large number of columns. plug core for measurement

The second type is the calculation and acquisition of well logging. According to the different logging methods used, it can be divided into the permeability calculated by conventional logging and the permeability calculated by nuclear magnetic resonance logging. The advantage of this method is that it can continuously calculate the reservoir Permeability, but also need a large number of core gas porosity and permeability data for porosity-permeability relationship fitting, and also need to obtain logging data

[0003] When it is difficult to obtain the plunger core (the core is fragile, etc.), and the gas permeability data of the core is lacking, the rock permeability evaluation will be more difficult

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