Method for remodeling three-dimensional pore structure of core

Abstract

The invention relates to a method for remodeling a three-dimensional pore structure of a core. The method comprises the following steps of carrying out high-resolution three-dimensional micro-CT (Captive Test) on a full diameter core so as to generate full diameter core CT data; selecting a core matrix from the full diameter core to carry out a higher-resolution three-dimensional micro-CT or a casting sheet experiment so as to obtain the information of a pore structure of the matrix; obtaining a secondary three-dimensional pore structure through three-dimensional CT remodeling by utilizing the full diameter core CT data; obtaining the three-dimensional pore structure of the matrix through the three-dimensional CT remodeling by utilizing the obtained information of the pore structure of the matrix or through geological statistics remodeling by utilizing sheet images; integrating the three-dimensional pore structure of the full diameter core with the three-dimensional pore structure of the matrix so as to obtain a three-dimensional fine pore structure of the core, which is provided with both secondary pore characteristics and matrix pore characteristics; and obtaining parameters of pore structures with different dimensions of the core and parameters of connectivity of three-dimensional space according to the three-dimensional fine pore structure of the core.

Description

technical field [0001] The present invention relates to the technical fields of core analysis, description, oil and gas reservoir evaluation, etc., in particular to the description and quantitative analysis of the three-dimensional distribution and spatial connectivity of different types of pores such as reservoir core matrix, secondary fractures and caves, etc., specifically a A method for reconstructing the three-dimensional pore structure of a rock core. Background technique [0002] As reservoirs with low porosity, low permeability, and complex lithology gradually become important targets for oil and gas exploration, a series of petrophysical problems related to pore structure are gradually emerging, such as: how to explain the permeability of reservoirs with the same lithology and similar porosity Huge difference in rate and resistivity? How to determine the effectiveness of low porosity and permeability reservoirs and so on. Both theory and practice have shown that i...

AI Technical Summary

Problems solved by technology

The resolution of the electron microscope is high, and the fine pore throat characteristics of the core can be obtained, but its disadvantage is that only the two-dimensional pore structure characteristics can be obtained, and the three-dimensional characteristics such as the spatial connectivity characteristics of the pores cannot be obtained.

In addition, the volume of samples analyzed by electron microscopy is very small, which can basically only reflect the characteristics of matrix and micropores, and cannot obtain the characteristics of larger-scale secondary pores such as cracks and caves.

Cast thin sections can only reflect the two-dimensional characteristi

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