Fracking, the commonly known term for Hydraulic fracturing, is a form of mining which forces natural gas out of the Earth's crust. It is different from conventional drilling used to extract oil or gas. During fracking, a vertical well is extended into a horizontal well which penetrates the shale layers. Shale is a type of rock made up of clay sediments, quartz, and other minerals.
Windmills of the Karoo
Typical area in the Karoo where fracking will take place
The Karoo grey shale layers are rich in natural gas and are considered to be the richest sources of shale gas fossil fuel in the world.
The grey shale layer is usually 2 - 3 kilometer deep, but the depth varies. In some places, e.g. Lainsburg, the shale layer appears on the surface.
The entire Karoo Basin had very large rivers with extended floodplains, all covered in vast swamps, buried in layers of sediment, formed the shale gas that is now in demand.
Fuel Companies: areas of operation in South Africa
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The following fuel companies are currently operating in South Africa:
- Anglo Coal
- Falcon O&G
- Sasol/Statoil/Chesapeake
- Shell
- Sunset Energy
Of all of the above, Shell is the largest company that has an interest in fracking in South Africa. Our government has allowed Shell to start a five-year exploration phase late in 2013. During this phase, no actual fracking may take place. Instead, environmental assessments will be carried out, such as measuring the composition of chemicals in existing municipal and other wells in the area. All these wells, there are several thousands of them, draw water from the water table.
Fracking allows oil and gas companies to extract shale gas that is tightly bound to shale. It is estimated that shale gas releases 48% less greenhouse gas than coal burning.
Fracking: How it works
Hydraulic fracturing causes natural faults (weak joints) in the shale to open up and release shale gas. Hydraulic fracturing is achieved by injecting more than 2 million cubic meters of water per annum into the well. The volume of this water is equivalent to 150 large swimming pools. The water is mixed with sand, a variety of salts, and several toxic chemicals. This is done under extremely high pressure which causes local earthquakes and allows the Karoo shale to crack and release gas into the open fissures (cracks). The sand in the mixture keeps the fissures open so that the gas can flow up the well to be collected on the surface.
"Well to Hell" Russia's 12 km-kola-super-deep borehole
This hole is known as "The Well to Hell" happened in Siberia Russia. According to the Bible, the world itself will become a living hell in the end days! Researchers plan to drill a 10-kilometer hole in the Eastern Cape to study what the effects of fracking for shale gas will have on the environment.
Stop Fracking!
Fracking remains a controversial issue as a result of its potential impact on the environment. The process weakens the Earth's crust to enable the gasses and toxic chemicals in the fracking fluid can escape to the surface. The Karoo basin also has large, underground, natural salt lakes. Fracking can cause this salt water to rise and infiltrates the freshwater aquifers and the water table.
On the hunt for shale gas in The Karoo
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The chemical mixture contains cancer-causing substances and other poisons that may cause illness. In addition to shale gas, methane is also released and is potentially explosive. Heavy machinery and trucks will have an effect on the environment. To date, all forms of purification and the disposal of the toxic wastewater has proven to be less than successful and no one has found a way to purify polluted underground water.
In the USA where fracking has been done for several decades, human diseases and livestock losses have been reported, which may have been caused by water consumed from wells near fracking sites.
Some countries like France and Bulgaria, have banned fracking.
