Oil Shale

Of growing importance in the area of energy is Oil Shale, which is also known as "the rock that burns". Simply put, this is a type of spongy rock that contains a lot of oil-like organic material called kerogen.

Oil shale forms in much the same way that biotic oil deposits form. Organic matter is deposited on the ground or bottom of a water body, and it is then covered with silt. This is then compressed into rock.

The difference between shale and other fossil fuel deposits is that the oil is trapped inside the rock. It has not been squeezed out to form pools of liquid oil such as found in scattered form in the Bakken oil field.

The implications of this are immediately obvious. If we are to extract fuel from these rocks it is going to require a time consuming and energy intensive process. Such a process does exist and the ever rising cost of oil is making that process more economically viable as time passes.

The Extraction Process

The issue with oil shale is that extracting and refining the hydrocarbons in the rock is a difficult and expensive process. This becomes obvious when we consider the amount of processing involved in regular oil, as shown below:

The shale rock is first mined, then crushed, then it has to be heated in the absence of oxygen to high temperatures (up to 500 degrees Celsius or 932 Farenheit) where the kerogen breaks up into smaller molecules. This process is called "cracking". The smaller oil-like substances that result from the cracking process then need to be refined in the same way that regular crude oil is, using the process of fractional distillation.

The Future for Oil Shale

Whether oil from shale rock will become a major source of fuel in the future is not clear. At present a great deal of Western infrastructure relies on oil and other hydrocarbon "fossil" fuels. If this infrastructure is not upgraded to make use of renewable energy sources then at some stage large scale production of fuel from shale will become economically viable. Given that there are immense amounts of oil bearing shale present in the world that dwarf the amount of crude oil available, it is highly likely that the most promising of these fields, such as the Green River Formation, will be opened up for commercial production in the near future.

However, the effects on the environment from utilizing all the fossil fuel sources on earth could be disastrous. Surely it makes more sense to develop more commercial scale renewable energy sources to replace our dependence on oil and like fuels.