Formation Mechanism of “Large-Area Sweating” Water Seepage from Deep Mine Sandstone Pores

Figure 3

The original samples were divided into four groups to carry out various laboratory tests. (a) Height 25.4-50.8 mm and diameter 25.4 mm for the porosity and permeability tests. (b) Casting thin sections for the Zeiss Imaging-2M polarizing microscope observations. (c) Height 6 mm and diameter 4 mm for the SEM observations. (d) Crushing, grinding, and removing cement with hydrochloric acid and drying for the grain sizes analysis.