Shale matrix reservoir pore space representation method

Abstract

The invention relates to a characterization method for pore space of shale matrix reservoirs. Based on different types of pores in shale gas reservoir cores, based on the superposition coupling method, a construction theory for digital cores generated by a hybrid method while considering organic pores and inorganic pores is established. with method. The digital core that considers organic pores and inorganic pores is constructed by superposition algorithm, which not only retains the geometric topology information of inorganic pores, but also retains the spatial position information of organic micropores, and can describe the special pore distribution characteristics of shale rocks at the same time. The established digital core was analyzed for geometric topology, and the pore radius distribution and coordination number fit well with the experimental results, which verified the correctness of the construction method and numerical analysis method. This method establishes a basic platform for subsequent shale medium pore structure analysis and microscopic flow simulation.

Description

technical field [0001] The invention relates to the technical field of numerical simulation of oil and gas field development engineering, in particular to a characterization method for pore space of shale matrix reservoirs. Background technique [0002] In order to realize the efficient development of shale gas reservoirs, the study of gas migration mechanism in micro-nano pores is one of the key mechanical issues, and digital cores are the basis for micro-nano scale flow simulation. Therefore, the identification and quantitative description of shale micro-nano pores and the establishment of an accurate characterization method for shale reservoir pore space have become the focus and difficulty of research. [0003] The pore structure of shale is complex, including nanoscale organic pores, nano-micron pores in inorganic minerals, and micron-millimeter natural fractures. Mud shale has different degrees of thermal evolution, resulting in different types of pores. The phase st...

AI Technical Summary

Problems solved by technology

However, whether it is directly constructed by physical methods or randomly reconstructed using two-dimensional image data, only digital cores of a single scale or single composition can be constructed, which is not accurate enough for shale with strong heterogeneity. Some scholars suggest that Characterization means for industrial CT-micro CT-nano CT / FIB series scanning analysis

But even so, it is difficult to consider both organic and inorganic pores at the same scale

Images