The geologic time scale is a way of representing deep time based on events that have occurred through Earth's history, a time span of about 4.54 ± 0.05 billion years. [3]

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Dec 1, 2025 · The geologic time scale is the “calendar” for events in Earth history. It subdivides all time into named units of abstract time called—in descending order of duration— eons, eras, …

Jan 11, 2025 · The Geologic Time Scale or Geological Time Scale (GTS) is a chronological framework that organizes Earth’s history into various units based on geological and …

Feb 13, 2023 · The geologic time scale (GTS) is a chronological framework that organizes Earth’s 4.6 billion-year history based on major geological and biological events. It allows scientists to …

Oct 5, 2021 · Geologic time scale showing the geologic eons, eras, periods, epochs, and associated dates in millions of years ago (MYA).

The Geologic Time Scale above is a helpful reference to use along with the information provided below. The left half shows a timeline of Earth’s geologic history which is split into Eons, Eras, …

The geologic time scale is a system of chronological classification used to organize and subdivide Earth's history. It is based on the physical and biological evidence preserved in the rock record.

The BGS geological timechart provides colourful reference material for use in schools, colleges and at home, setting out the geological timescale and geochronological terms we use at BGS.

This page contains the latest version of the International Chronostratigraphic Chart (v2024-12) which visually presents the time periods and hierarchy of stratigraphic names of Earth's …