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The geological time cale is a chronological system that divides. Earths history into eras, periods and epochs. It’s a way to understand and communicate the timing of geological events and the evolutions of life on Earth.

What is it?

• The Geological Time scale is a chronological system that organizes Earths history into different times periods, based on major geological and biological events.

• It’s like a timeline or a calculator for the earth, Showing how the planet and how its life changed over the billion years.

• The scale is based in the rock record and the fossil record, which provides clues about the past.

• It’s used by the geologists, palaeontologists, and other earth scientists to study the history of earth.

How is it organised?

Eons:

The largest divisions, representing billions of years of earths history. The most recent eon is Phanerozoic.

Eras:

Subdivisions of eons, lasting hundreds of millions of years. The Phanerozoic eon is divided into the Phanerozoic eon is divided into the Paleozoic, Mesozoic, and Cenozoic eras.

Periods:

Smaller units within eras, defined by more prevalent events, For example, the Cenozoic Era is divided into the Paleogene, Neogene, and Quaternary periods.

Epochs:

Further subdivisions of periods, used for more recent geological time.

Ages:

The smallest unit of the timescale, representing relatively small intervals within epochs.