Coal and oil are two of the main sources of human energy. Highly polluting and increasingly replaced by clean energy has marked the history of humanity. Let’s see the origin and when and how coal and oil were formed:
WHEN AND HOW THE COAL WAS FORMED
The first living beings that managed to leave the sea and adapt to living in contact with the air were some algae, from which more complex plants later derived.
Once adapted to the new environment, the plants underwent a very rapid evolution and invaded all the emerged lands, covering them in green and changing the face of our planet.
The period that saw the greatest development of the forests was the Carboniferous, so called because in that distant era the great coal deposits were formed.
The black pieces of anthracite, which are still used today in heating many homes and in industries, therefore have a history of millions of years old.
They were formed from the decomposition of the forests that 300 million years ago covered the earth’s surface. Over time, the huge logs knocked down by old age or windstorms formed high layers of wood, which were later buried by layers of mud and sand.
Other cataclysms caused the subsequent collapse of these deposits. The wood, not being in contact with the air, did not rot but underwent a profound transformation due, in part, to the severe pressures and the terrestrial heat.
What is now left of the ancient forests are the fossil carbon strata found in the subsoil. Depending on the time and conditions in which they were formed, we have different kinds of fossil coal.
WHEN AND HOW OIL WAS FORMED
Today coal has lost the supremacy it held in the field of fuels and has given way to oil, the valuable substance that springs from the deep layers of the soil.
To search for oil, they have gone so far as to make deserts habitable, to build huge floating platforms on the sea, and to drill rocky strata to depths of more than 5,000 meters, investing enormous sums in all of this.
However, these are more than amortized since, once a deposit is reached, more and more tons of “black gold” (this is what oil is called) constantly pour out of the well, which, through special pipelines, is transferred to the refineries. or the tankers.
Oil is younger than coal. Its formation dates back to a more recent period in Earth’s history, more or less to the time of the great dinosaurs. Precisely in the Mesozoic era the undulations and modifications of the earth’s crust continued.
In various regions of the globe, very high deposits of marine and lagoon sediments accumulated, and the stratification of these deposits indicates that many alternating elevations of the lands and seas took place then.
The most important period of the Mesozoic era is the Cretaceous, whose name derives from the term craie , which in France indicates a calcareous powder that was formed precisely in those distant times. It is one of the longest periods in Earth’s history – indeed, it spanned millennia of years.