London-listed Fortune Oil in China has nearly doubled its paper holdings after a study of rock strata by Chinese geologists revealed 40.5 billion cubic metres of gas in place at the Liulin block, Shanxi province.

Methane levels in the coal-bed gases was 91 percent, while carbon-dioxide content of 3.9 percent meant gas quality suited natural gas transport by pipeline.

“The gas in place was estimated using the known thickness of the coal seams down to seam 10, which is at a depth of 500 metres to 1000m below ground,” a statement said, adding, “All these gas resources are therefore potentially accessible.”

Real gas recovery is dependent on “coal permeability, ground conditions and local coal mining as well as the need to de-water and develop each main seam in turn.”