What periods have the earth been divided into since its birth?

The earth has been divided into five periods since its birth: Archean, Archean, Paleozoic, Mesozoic and Cenozoic.

1, Archaean: The earth has just formed, there is no land, there is a Wang Yang. It started about 4.6 billion (or 5 billion) years ago and ended 2.4 billion years ago. The only fossils found are late fungi and low-grade cyanobacteria. Because all rocks have undergone many crustal changes and magmatic activities, deep metamorphism has taken place, and it is difficult to preserve fossils.

2. Proterozoic: the embryonic form of land appeared. The Eurasian plate began to separate in the late stage. Single-celled plankton appear in the ocean. During the long period from 2.5 billion to 800 million years ago, the biological world evolved from prokaryotes to eukaryotes, dominated by fungi and algae, so Proterozoic was also called the era of bacteria and algae.

3. Paleozoic: Seven major plates of Eurasia were basically formed. Production of algae, lower invertebrates and a few plants. Paleozoic includes Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian. Among them, Cambrian, Ordovician and Silurian are collectively referred to as Early Paleozoic, while Devonian, Carboniferous and Permian are collectively referred to as Late Paleozoic.

4. Mesozoic: It can be divided into Triassic, Jurassic and Cretaceous. Animals and plants produced and multiplied in large quantities, the climate began to form, and dinosaurs experienced production and extinction.

5. Cenozoic era: The Cenozoic era 65 million years ago was the latest geological era in the history of the earth. The Cenozoic is divided into three periods: Paleogene, Neogene and Quaternary. The Cenozoic era is characterized by the high prosperity of mammals and angiosperms. Because the biological world gradually presents a modern look, it is named the Cenozoic era, that is, the era of modern biology.

The birth of the universe 654.38+0.5 billion years ago laid the material foundation of the earth. As a planet, the earth originated from the primitive solar nebula 4.6 billion years ago.

Since then, the earth system has changed from simple to complex, and its various components are interrelated and influence each other. The movement of the earth system and the morphological changes, life phenomena and life activities brought about by the movement have all become the history of the earth.

The material that formed the primitive earth is mainly the original material of the nebula disk, and its components are mainly hydrogen and helium, accounting for about 98% of the total mass. In addition, there are solid dust and matter thrown out by the early contraction and evolution stage of the sun. During the formation of the earth, due to the differentiation of substances, light substances are constantly separated from volatile substances such as hydrogen and helium, and are taken out of the solar system by solar light pressure and substances thrown out by the sun. Therefore, only when heavy matter or earth matter is condensed can the original earth gradually form and evolve into today's earth.

In the process of earth evolution, some astronomical and geological events will occur, and the time period of these events is called geological period.

In various geological periods, major events related to the earth, the solar system and the earth in space have left records on the earth itself, crustal movement, strata, rocks, structures, paleontology, paleomagnetism, glaciers, paleoclimate and many other aspects.

In different geological periods, different geological processes have different characteristics.

The history of the earth can be divided into: earth formation period, crust formation period, pre-solar system entry period, solar system entry period, earth-moon system formation period and newborn period, as shown in the following table.

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