What is Precambrian?

What Does Precambrian Mean

The first thing we are going to do is determine the etymological origin of the Precambrian term. In this sense, we can say that it is the result of the sum of the Latin prefix “pre-”, which means “before”, and Cambrian, which derives from the Latin voice “Cambria”, which refers to the original natives of what today it would be Wales.

The Precambrian is one of the periods of the geology timescale . This is the first stage in the history of the planet, which begins with the formation of the Earth and extends about 570 million years ago . When it is written with a lowercase initial, the term refers to what is related to that period.
During the Precambrian , primary life forms began to emerge. This period lasted between 4,000 and 5,000 million years, until the Cambrian began . Due to the antiquity, the low amount of fossils found and the orogenic modifications, it is very difficult to carry out studies on these years.

It is considered that the Precambrian is divided, in turn, into three periods:

-Hadic Aeon, a phase that took place in the period between 4,500 and 3,800 million years. In it there was a great meteoric bombardment and the Earth, the Moon and the lithosphere were formed.

-Archaic Aeon, covers the phase between 3,800 and 2,500 million years. The first continents emerged and plate tectonics began.

-Eon Proterozoic, dated between 2,500 and 540 million years. In this phase, the first continents shape Pangea I, the first eukaryotic cells appear and the Ozone Layer is formed.
Among the most salient events that occurred in the Precambrian , are the appearance of Ediacaran organisms and the first sponges , the division of the supercontinent known as Rodinia , the emergence of Columbia , the oxygenation of the atmosphere and even the development of our satellite. natural (the Moon ) through the collision between the Earth and a planet called Theia .
In addition to all the above, we cannot ignore other important events that are considered to have taken place in the stage in question:

-The hydrosphere was formed as well as the atmosphere itself.

-The first continental nuclei arose, which were given the name of cratons.

-It was home to a great ice age.

-There were glacial periods that alternated with others of a desert nature, let's put it like this.

-This period is significant due to the fact that it currently occupies 88% of Earth's history.
The Precambrian was a period of great geological modifications. Experts have determined that volcanic activity sent carbon dioxide and water vapor into the proto-atmosphere , causing the temperature to drop. From then on, the rocks began to solidify. Water vapor was also key to the development of the oceans.

With the oxygenation of the atmosphere in the Precambrian , on the other hand, the ozone layer was formed about 1.8 billion years ago, protecting living organisms from the solar ultraviolet rays.

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