On the basis of high methane content per tonne of coal, Bhatdee is considered a Degree 3 mine under Bharat Choking Coal. (policybazaar.com)
Since methane is a greenhouse gas 25 times as potent as carbon dioxide, such a scenario would trigger a «climate catastrophe», they say, increasing the methane content of the planet's atmosphere twelve-fold, and raising temperatures by 1.3 ˚C. (newscientist.com)
«In an oil reservoir, there is a layer of gas above the oil which has a methane content of 50 to 85 percent. (sciencedaily.com)