ABSTRACT
Methane in coal formed and accumulated over geologic time. The main methane mass is found in virgin rock in a system that consists of cracks, canals, and open pores (that determine •ltration capacity) and closed pores (not connected by means of transport links with •ltration capacity). The seam methane pressure in virgin rock is homogeneous because of the homogeneous structure constants according to Bernoulli’s equation and its pressure correlates with rock pressure.
