The invention provides a pore geometric morphology fine characterization method based on confining pore forming of
mineral particles, which comprises the following steps: S1, performing fine characterization of the
mineral particles based on geometric morphology characteristics, and accurately identifying the
mineral particles in combination with characterization results; s2, performing geometric shape quantitative characterization on different types of pores from the angles of pore diameters, roundness, flatness, shape indexes and
corner angle indexes to obtain geometric shape parameters of the pores; s3, on the basis of the recognized mineral particles, the names of confinement pores are determined, clustering analysis is conducted on the confinement pores in combination with the geometric morphology quantitative characterization result obtained in the step S2, and a pore
classification scheme is established; and S4, based on a
classification scheme and a quantitative characterization result, determining development characteristics of shale reservoir pores, establishing a
porosity contribution index model formula, and matching and verifying a reservoir
physical property result. According to the method, through comprehensive analysis of the pore morphological characteristics,
solid data support and theoretical basis can be provided for scientific evaluation of a high-quality pore development mode.