Paleozoic Era, also spelled Palaeozoic, major interval of geologic time that began 541 million years ago with the Cambrian explosion, an extraordinary diversification of marine animals, and ended about 252 million years ago with the end-Permian extinction, the greatest extinction event in Earth historyPaleozoic times saw parts of what was to become the Scotia Sea situated close to the paleo-Pacific margin of Gondwana.
The Mesozoic Era began 252.2 million years ago,The ancestors of major plant and animal groups that exist today first appeared during the Mesozoic, but this era is best known as the time of the dinosaurs.Three of the most important periods of the Mezozoic were The Triassic Period, The Jurassic Period, and The Cretaceous Period.Two of the largest volcanic events in Earth’s history occurred during the Mesozoic. The Central Atlantic Magmatic Province, a huge volume of basalt, was created at the end of the Triassic during the initial rifting of Pangea.
The Cenozoic Era was the third of the major eras of Earth's history, it began about 66 million years ago and is extending to the present. It was the Era in which the continents got into their actual geographic positions and during which Earth's organisms evolved toward actual plants and animals. Extinction of many groups of giant mammals, allowed smaller species to diversify because of their predators no longer existed.
Periods: Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene.
Cenozoic
Precambrian
Geological Time Scale
Paleozoic
The Precambrian age is the earliest geological which are marked by sedimentary rocks of different layers. Each rock is a permanent record of earth’s past including the fossilized remains of the animals and plants which were form with the rocks.
Then they were divided into Eons:
Periods: The Hadean (4600–4000 Ma), Archean (4000-2500 Ma) and Proterozoic (2500-541 Ma).
Mesozoic Era
