The term fosìl dereviva from the Latin “fosilis” is used to refer to all those vestiges of ancient organisms that, thanks to the sedimentation of the rocks, have been preserved over time since through it they become part of the crust land. For fossilization to occur, the organism must have been buried shortly after its death.
Fossilization is carried out through a series of both physical and chemical processes, causing the organism to undergo a series of transformations both in its structure and in its composition, fossilization is considered a very strange phenomenon, since the vast majority of the parts that make up the beings of organic origin decompose after dying over time and this process requires many years.
The process can be carried out in three different ways:
The mineralization: here the bones or the residues thereof are changed, since minerals that these structures are modified to contain the agregarles minerals, after that the remains are converted into rock.
Carbonization: the fossilized body loses substances such as oxygen, nitrogen and hydrogen, being composed mainly of carbon, usually occurring in plants or animals that have died as a result of crushing rocks.
Casting and molding: they are positive or negative images of the fossils or their parts, it can be of three types. The exterior, which is when the body suffers an impression only on its exterior or on its surface, thanks to substances such as clay that cover it. The interior, in this case the fossil takes the internal form of the organism, since the substance penetrates inside it, thus leaving an internal mold. Finally, there is the counter mold, in order to carry it out, it is necessary to first form a first mold and from it the second and final mold will be formed, which will be an exact replica of the fossilized organism.
Fossils represent an important part for sciences such as geology and biology, since thanks to them it has been possible to determine the chronological scales used in stratigraphy, in addition to being able to determine the ages of the layers of the earth.
