In March this year Mineral Resources Minister Mosebenzi Zwane announced that the government had given the go-ahead for shale gas development in the Karoo region.
In a speech, Zwane said "Based on the balance of available scientific evidence, government took a decision to proceed with the development of shale gas in the Karoo formation of South Africa".
At the time the department estimated that up to 50 trillion cubic feet (Tcf) of shale gas was recoverable in the Karoo Basin, especially in the Eastern, Northern, and Western Cape provinces.
It now turns out that there is almost 40 times less shale gas in the Karoo than previously thought.
Prof Michiel de Kock, head of Geology, University of Johannesburg says the resource estimations have been decreasing over the years and are based on the organic carbon content of the shales and not on any gas measurements in the Karoo.
A study in 2011 estimated 485 trillion cubic feet. The same people who did the study again in 2013 revised these figures to 390 trillion cubic feet.— Prof Michiel de Kock, head of Geology, University of Johannesburg
All of these are estimations.— Prof Michiel de Kock, head of Geology, University of Johannesburg
Our study found the organic carbon content in the Karoo is overcooked explains De Kock. He goes on to say this means the gas and oil have been released but they weren't preserved well and have overheated.
A realistic estimate of there being gas in these areas would amount to 13 trillion cubit feet, which is still a big resource.— Prof Michiel de Kock, head of Geology, University of Johannesburg
To hear the rest of the interview, listen below: