Earth Sciences

Geological ages

Geological ages or periods are what geologists and paleontologists use to organize the temporal flow of history on Earth's surface. Because of the great space of time, 4.5 billion years, it is most useful if it is divided into different stages in order to study it. These divisions are not randomly assigned but correspond to the different changes that have occurred in the geology, geography, climate, and other characteristics of the earth. For the most part, they follow the evolution of life or the lack of it. The transformation that occurs in geological periods can be caused by some important geological event, such as a collision within the solar system, such as a comet or a meteor. Prolonged volcanic episodes can also be an important agent of change.

What are geological ages?

A geological age is an extended unit of time that includes millions of years in which a series of biological and geological changes occur that are directly related to the formation of the Earth and the life on it.

About geological ages

The geological ages of the earth are four and are as follows:

Classification of geological ages

The history of the earth is classified into five important stages, each with a different number of years. This classification is as follows:


Among the main characteristics that we can mention about geological ages are the following:

What are the geological ages for?

The geological ages serve to determine the epoch in which the rocks were formed, the strata and the step and transformation that the living beings had until reaching their present state. The study of climate, oceans and continents is possible through the study of geological ages.


In ancient Greece, Aristotle observed that fossils of seashells on the rocks resembled those found on beaches. He concluded that the fossils in the rocks were made up of living animals and reasoned that the positions of land and sea had changed over long periods of time. Leonardo da Vinci agreed with Aristotle’s interpretation that fossils represented the remains of ancient life. Persian geologist Avicenna and 13th-century Dominican bishop Albert the Great extended Aristotle’s explanation of a theory of a petrifying fluid. At the end of the 17th century, Nicholas Steno pronounced the principles of geological time scales. Steno argued that layers of rock or strata were placed in succession, each representing a “portion” of time. He also formulated the law of superposition, which states that any given stratum is probably older than the previous ones and younger than those below.

Written by Gabriela Briceño V.

How to cite this article?

Briceño V., Gabriela. (2019). Geological ages. Recovered on 23 February, 2024, de Euston96:

Recommended for you