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The Karoo’s shale gas resource could potentially change the economic landscape of South Africa, as it held significant energy and job creation potential, University of the Free State director of ground water studies Dr Danie Vermeulen said on Wednesday.
Citing a study by Econometrix, he said shale gas could create an estimated 300 000 to 700 000 direct and indirect jobs. “This won’t all be happening in the Karoo, but looking at this in a bigger picture, you’ll see that there are other job opportunities linked to this industry.”
Vermeulen said the country would never know the real extent of the potential and whether there was a viable source of shale gas in the Karoo if the experts were not allowed to carry out research, or in other words, do exploration.
At 485-trillion cubic feet, South Africa is estimated to host the world’s fifth-largest shale gas deposit, after China, the US, Argentina and Mexico.
Vermeulen questioned whether South Africa had enough water for hydraulic fracturing, or fracking, which involves blasting water mixed with sand and chemicals underground to free trapped hydrocarbons from shale formations. “This too will remain unknown until research has been carried out,” he said.
He pointed out that while fracking used significantly less water than other industries such as coal mining, it would take place in one of the country’s driest regions.
Further, Vermeulen said that, unlike earlier years, flow-back water would be stored in sealed tanks and not in flow-back dams, while fracking would not contaminate the water in an area, as the drilling of the wells would go far deeper than the groundwater aquifers. “Every well has four steel casings – one within the other – with the gaps between them sealed with cement,” he said.
In September, Mineral Resources Minister Susan Shabangu lifted a moratorium on the exploration for natural gas in the Karoo. Companies such as Royal Dutch Shell, Falcon Oil & Gas and Bundu Oil & Gas are now looking to employ the practice.
Vermeulen said that Shell currently had an exploration licence of about 90 000 km2, but would essentially only be able to explore 28% of this range, as the Square Kilometre Array radio telescope project; the South African Large Telescope in Sutherland; farmland; water pipelines and other infrastructure intercepted the land.
Further, in this 28%, the company would need to find “sweetspots” which did not contain dolerite, as dolerite intrusions could exceed 900 °C, which could be detrimental to exploration. “Ultimately, this would leave the exploration company with about 5% of this 90 000 km2 to explore.”
He concluded that boreholes were generally sunk and the shale fractured in a relatively short timeframe, with the only visible evidence of a gas well being a pipeline leading from the well to a central storage facility. “When a gas well is spent, the surface area could be fully rehabilitated, although the chemicals pumped into the earth’s crust can never be removed.
“Thus far, I will promote it, because we need energy in this country.”
The March 2012 Econometrix report found that shale gas would add between R80-billion and R200-billion to the country’s yearly gross domestic product if only a small portion of the speculated shale resource base was exploited.
Edited by: Mariaan Webb
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