The pore geometry and topology properties of pore space in rocks are significant for a better\nunderstanding of the complex hydrologic and elastic properties. However, geometry and topology\ninformation about the sandstone pore structures is not fully available. In this study, we obtained the\ntopological and geometrical pore parameters from a representative elementary volume (REV) for\nfluid flow in sandstone samples. For comparison, eight types of sandstones with various porosities\nwere studied based on the X-ray micro-computed tomography technique. In this study, the REV\nsize was selected based on the parameters from the respective pore network models (PNM), not just\nthe porosity. Our analysis indicates that despite different porosity, all the sandstone samples have\nhighly triangular-shaped pores and a high degree of pore structural isotropy. The high porosity group\nsandstones exhibit wider ranges of pore sizes than the low porosity group sandstones. Compared to the\nhigh porosity group sandstones, the low porosity group sandstones samples showing a higher global\naspect ratio, indicating some pores exist in the form of bottlenecks. The pore topological properties of\ndifferent sandstones show a high dependence of the porosity. The high porosity group sandstones\nobtain large coordination numbers, large connectivity densities and low tortuosities. The results from\nthis study will help better understand the complex pore structure and the fluid flow in sandstone.
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