3D visualization of tectonic coal microstructure and quantitative characterization on topological connectivity of pore-fracture networks by Micro-CT

Research on the connectivity characteristics and topological relationships of pore-fracture networks is crucially significant for systematic understanding microstructure evolution original tectonic coals. From aspects digitization, visualization, non-destruction, topologization quantitation, Micro-CT adopted to characterize original, reconstructed The results indicate that roughly vertical distribution among cleat system in coal regularly splits matrix into several cubic blocks. Tectonism induces fundamental transformation microstructure, associated with well-developed micro-fractures sporadic pores distributed spatial scale. With external stress loading, internal sharply decline gradually evolves widely-distributed pore locally disorderly dispersed micro-fractures. Following morphological thinning algorithm, skeletonization models were created demonstrate mean tortuosity has highest value 1.2213, followed by coals 1.1741 1.1205, respectively. Based skeletonization, “ball-rod” model its quantitative parameters reveal equivalent structure space significantly increases, compared coal; however, after loading decreases slightly 37.75%. may facilitate generate a high coordination number >10, enhancing nevertheless, dropped dramatically due loading. mentioned above, pore-scale flow simulation micro-topological PNMs was conducted discovering pressure distributions different directions are more concentrated uniform than while latter non-uniform pattern structural anisotropy heterogeneity. aforementioned have guiding significance revealing network coal, as well fluid transporting visualization.