In recent years we have understood, thanks to a multitude of awareness campaigns, the importance of looking for alternatives to fossil fuels to obtain energy. One of those fossil fuels is oil, that black gold capable of fueling wars, destroying ecosystems and bringing down economies. It may seem like an unlimited resource to us, but clearly it is not. Its main problem is how much it pollutes, but also that, although new wells can be opened, in general it is a finite resource. To understand this, it is best to first be clear about what the origin of oil. And there are still many myths around this topic, such as the one that claims that it comes from dinosaurs.
Oil, broadly speaking, is a substance that simmers for millions of years. Literally. It is formed from organic matter, generally from zooplankton and phytoplankton. Or, in other words, tiny animals and plants, microscopic in some cases, that are deposited in basins of aquatic environments to later decompose.
Now, the decomposition behind the origin of oil is not a normal decomposition of organic matter. It is given to very specific conditions of pressure, oxygen and temperature, which facilitate the appearance of hydrocarbons. But what are those conditions?
Parameters necessary for the origin of oil
A basin is a depressed area of the Earth’s crust in which sediments accumulate.
In aquatic environments, in addition to sediments, remains of organic matter from plankton can be deposited. After, sediments continue to accumulateso that an environment without oxygen is created, in which many of the bacteria that are normally responsible for decomposing that bacteria cannot proliferate.
However, this decomposition occurs in other ways. On the other hand, there are anaerobic microorganisms, capable of decomposing organic matter without the presence of oxygen. Furthermore, when enough sediments have accumulated, pressure and temperature conditions occur that also facilitate the decomposition and transformation of that organic matter into hydrocarbons, which are chemical compounds formed mainly by hydrogen and carbon. The temperature must be within a very specific window, which ranges from 50ºC to 150ºC. If it is below, oil is not formed and if it is above it, it is transformed into gas and is lost.
If everything has gone well, that will be formed black viscous liquidwhich becomes trapped in the rock and must be extracted by drilling wells.
Why is it said that it comes from dinosaurs?
The entire process that gives rise to oil takes millions of years to complete. It is said that the majority of what is extracted today began to form in the Mesozoic. This is a geological era that began ago 251 million years and ended ago 66 million years. Dinosaurs actually lived at that time.
Therefore, since it is often said that the origin of oil is in dead, decomposing animals, the myth has been generated that it is made from dinosaurs. However, we have already seen that these animals are the ones that form zooplankton. Small crustaceans, fish larvae and some microscopic marine animals, such as rotifers. It has nothing to do with the dinosaurs.
Yes, a dinosaur could die, fall into a lake and decompose at the bottom of the water, but the conditions are not the same. Tiny organic matter is needed to fill marine basins and mix with sediments. This is how oil is formed. The rest are myths and it is important to know, although not as important as looking for ways to stop using it.