Research Article
Influence of Overlying Caprock on Coalbed Methane Migration in the Xutuan Coal Mine, Huaibei Coalfield, China: A Conceptional Analysis on Caprock Sealability
Figure 3
Field sampling process of caprocks and the standard sample preparation.
(a) Surface drilling in the field |
(b) The core of drilling hole |
(c) The standard sample () of caprocks |