The much-touted vast shale gas potential of South Africa’s Karoo region is “likely highly inflated” with a more realistic estimate of resources a mere fraction of the current highest estimate, according to an academic study.

The likely resource base is still, however, an attractive commercial opportunity, with sweet spots in the play possibly offering more positive numbers, the report published in academic publication South Africa Journal of Science said.

Current resource estimates for shale gas in the semi-arid Karoo region are between 13 trillion cubic feet and 390 Tcf.