Influence of Overlying Caprock on Coalbed Methane Migration in the Xutuan Coal Mine, Huaibei Coalfield, China: A Conceptional Analysis on Caprock Sealability

Figure 9

Permeability of cap rock samples under different confining pressures. Note: loose bed refers to Quaternary and Neogene rocks; Redbed refers to Paleogene rock. Note: the data points were derived from the average values of four surface drilling holes (75-7, 74-7, 74-11, 67-11, 73-14, and 75-8) that were calculated by the permeability of the coal-bearing rocks (sandstone, mudstone, and siltstone), Paleogene rocks (Redbed), and Neogene and Quaternary rocks (Loose bed).

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