Mining Publication: Effects of Hydraulic Stimulation on Coalbeds and Associated Strata
In studies conducted by the Bureau of Mines, two test areas were hydraulically stimulated and exposed by mining: one in the Pittsburgh coalbed at the Vesta No. 5 Mine, Washington County, Pennsylvania; and one in the Illinois No. 6 Coalbed at the Inland Mine, Jefferson County, Illinois. Induced fractures were contained totally within the coalbed with no adverse effect on the stability of associated rock strata. Induced fractures were vertical and were propagated normal to the direction of least residual tectonic stress. Gas production was increased fivefold to twentyfold by hydraulic stimulation.