What are fossil fuels?

Let me begin with a little bit of high school revision. Fossil fuels are composed primarily of carbon and hydrogen. There are basically three types of fossil fuels on Earth: coal, oil, and natural gas. It's common knowledge that fossil fuels are the remains of prehistoric plants and animals. That's why they're called "fossil fuels" (although they're not literally made from prehistoric bones, or at least not in any significant amount). Over a period of millions of years, these organic remains decomposed, and they got buried deep beneath rock and sea beds. A combination of heat and pressure caused the organic material to chemically alter into the fuel resources that we're familiar with today. The fuels became trapped between layers of rock in the Earth's geological structure, thus preserving them and protecting them from the elements up to the present day.

Hang on. Let's stop right there. Fossil fuels are dead plants and animals. And we burn them in order to produce the energy that powers most of our modern world (86% of it, to be precise). In other words, modern human civilisation depends (almost exclusively) upon the incineration of the final remains of some of the earliest life on Earth. In case there weren't enough practical reasons for us to stop burning fossil fuels, surely that's one hell of a philosophical reason. Wouldn't you say so?

The term "fossil fuels" seems to be bandied about more and more casually all the time. World energy is built upon fossil fuels, and this is of course a massive problem for a number of practical reasons. We should all be familiar by now with these reasons: they're a non-renewable source of energy; they're a major source of greenhouse gas emissions (and hence a major contributor to global warming); and they generate toxic air and water pollution. However, we seldom seem to stop and simply think about the term "fossil fuels" itself, and what it means.

The various fossil fuels trace their origins back to anywhere between 60 million and 300 million years ago. Coal is generally considered to be the older of the fuels, with most of it having formed 300 to 350 million years ago during the Carboniferous period (the period itself is named after coal). 300 million years ago, life on Earth was very different to how it looks today. Most of the world was a giant swamp. Continents were still unstable and were entirely unrecognisable from their present shapes and positions. And life itself was much more primitive: the majority of lifeforms were simple microscopic organisms such as phytoplankton; plants were dominated by ferns and algae (flowers weren't yet invented); terrestrial animals were limited to small reptiles and amphibians (the long-lost ancestors of those we know today); and only fish had reached a relatively more advanced state of evolution. Birds and mammals wouldn't be invented for quite a few more million years.

Coal is believed to be composed of the remains of all of these lifeforms, to some extent. The largest component of most coal is either plant matter, or the remains of microscopic organisms; however, the primitive animals of the Carboniferous period are no doubt also present in smaller quantities.

Oil and natural gas — which are typically formed and are found together — are believed on the whole to have formed much later, generally around 60 million years ago. Like coal, oil and natural gas are composed primarily of plant matter and of microscopic organisms (with both being more of marine origin for oil and natural gas than for coal). It's a popular belief that oil contains the decomposed remains of the dinosaurs; and while this is probably true to some extent, the reality is that dinosaurs and other complex animals of the time are probably only present in very small quantities in oil.

So, all of the three fossil fuels contain the remains of dead plants and animals, but:

  • the remains contain far more plant (and microscopic organism) matter than they do animal matter;
  • the remains have been chemically altered, to the extent that cell structures and DNA structures are barely present in fossil fuels; and
  • most of the lifeforms are from a time so long ago that they'd be virtually unrecognisable to us today anyway.

And does that matter? Does that in any way justify the fact that we're incinerating the remains of ancient life on Earth? Does that change the fact that (according to the theory of evolution) we're incinerating our ancestors to produce electricity and to propel our cars?

I don't think so. Life is life. And primitive / chemically altered or not, fossil fuels were not only life, they were the precursor to our own life, and they were some of the first true lifeforms ever to dwell on this planet. I don't know about you, but I believe that the remains of such lifeforms deserve some respect. I don't think that a coal-fired power station is an appropriate final destination for such remains. Carboniferous life is more than simply historic, it is prehistoric. And prehistoric life is something that we should handle with dignity and care. It's not a resource. It's a sacred relic of a time older than we can fathom. Exploiting and recklessly destroying such a relic is surely a bad omen for our species.

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Fossils truly depicts our own life cycle, how dinosaurs evolved to the present day man. Fossils are limited source of energy so we should use them wisely.


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suloshi fernando

it's a very facinating site i have read but there is a tiny problem that is it didn't answer my question and my question was "when fossil fuels was formed what was the geological name?" i wish you will improve and make it more facinating......

Suloshi Feranndo