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

Figure 7

Pore size distributions of cap rock samples from the MIP method. (a) Sandstone, siltstone, and mudstone; (b) Redbed. Note: each rock sample is obtained from the coal-bearing strata and Redbed in the surface drilling hole of 74-11.

(a)

(b)