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Coalbed methane (CBM) reservoirs are notoriously difficult to characterize for the existence of heterogeneity at several length scales. These length scales affect processes of desorption at the grain scale (<nm), diffusion at the micropore scale (nm), gas seepage at the mesopore (μm) and cleat (mm) scales, and production at scales of meters to kilometers. We report pore properties for 14 coal sublayers from three continuous coal seams (numbers 3, 5, and 11) from southeastern Ordos Basin, China. Semi-bright and semi-dull coals are the main coal types. Characterization and analysis across the scales is by X-ray computed topography (CT), mercury intrusion porosimetry (MIP), N₂ adsorption/desorption [Brunauer–Emmett–Teller (BET)], and nuclear magnetic resonance (NMR). Proximate and maceral group composition analyses show that the ash yield correlates negatively with the vitrinite content. CT scanning …