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Fossil Fuels Simply Explained
Lives lost billions spent. Pollution...Craziness!
Alternative energy is now a top priority
There seems to be quite a lot of confusion regarding what are fossil fuels; where are they found and where did they come from.
There are three kinds of fossil fuel: coal, oil and natural gas. They are all formed from organic plant life, changed by time, heat and pressure, under the surface of the Earth.
Coal has fallen into disfavour in the US and Britain, although it may soon be making a comeback. It is still the principle fuel in nations such as China, who still run huge mining operations.
Coal was formed from "Coal Measure" forests growing in enormous swamps in and around the Carboniferous period about 300 to 400 million years ago. As the forests died they formed a mass into which oxygen was absent, allowing the growth of bacteria to decay the plant mass until it formed peat. The peat was then crushed under further layers of peat and rotting plants resulting in chemical changes. The first formation was the brownish, crumbly coal known as LIGNITE. As the process continued under more heat and pressure from above, BITUMOUS COAL layers were formed. This was the coal most often used in the family fire grate. It is fairly hard, but easily busted with a light hammer.
If the amount of material above was sufficient, the process continued to one other stage, the formation of the prized ANTHRACITE. This is the rock hard, shiny black coal used by industry and applications requiring a hot-burning, high quality coal. All the energy released by modern man from coal - and, indeed, oil, is that stored by the plants using photosynthesis and the power of the sun, which was hotter back then than it is today.
A host of other products depend on coal and are the reason for its continued mining at a much reduced level in many places.
Oil and natural gas are also fossil fuels - known collectively as PETROLEUM (Greek "Petra," rock...leading to the Spanish "Piedra" and Latin "Oleum," oil)), but formed from teeming trillions of dead planktonic plants that existed close to the surface of the oceans and seas during prehistoric times. When they died, they slowly sank to the sea floor and were buried by subduction eventually, along with the mud that formed the sea bed. Over the millenniums, this mud turned into rock and the organic material formed tiny deposits of carbon-rich KEROGEN. Contrary to what many people imagine, oil does not form huge underground lakes in most cases, but is held in the oil bearing shales and other rock similar to liquid in a sponge and has to be driven out during the drilling process and afterwards. The oil has a tendency to flow upwards and may come up against an impervious layer of igneous rock and be trapped underneath. This situation would be what led to companies drilling into runaway "gushers" of oil and/or gas under huge pressure.
It can be very difficult and expensive to remove oil from oil bearing rock. Sometimes, the natural gas helps to pressurize and force the oil to the surface; alternatively, mining engineers have to pump water and other liquid combinations from the surface to aid in the recovery process. Oil is found in a variety of weights and coloration, the heavier, black oil formed under lower pressure, whereas the lighter oils, formed under high pressure, are pale and thin. All oil has to be refined before it is used. It is then used as petrol and diesel and kerosene and in the manufacture of asphalt, plastics and much more. The several types of gas found are all used and more is collected during the refining process.
In a way, it was a great shame man ever discovered fossil fuels, although it may have been inevitable. But we have learned to depend on them far too much at the expense of viable research leading to technology that would wean us away from such dangerous dependency. Now, we have a situation where oil cartels in the Middle East, as well as greedy domestic corporations, are holding the users to ransom. Prices are rising daily, and they never seem to go back down as once they did. Wars are fought using human rights excuses, but we all know oil and gas plays a large part in the decision to take up arms again. Yet still the large oil concerns continue to suppress, or to ignore, the technology that would allow us to use cleaner fuels and fuels not regulated by greedy commerce. This is hydrogen/electric cars, for example, they are here, but no one will put in the infrastructure needed to accommodate them.
We do seem at the verge of breaking through, however: if not, the price of petrol (gas), along with the draconian insurance and vehicle tax rates, will put car use beyond the possible for many of us.