It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (a scientific branch of geology that aims to determine the age of rocks).

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

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 paleontological evidence. It …

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, periods, epochs, and ages.

Jan 23, 2026 · 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 classify …

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, Periods, and …

Geologists have divided Earth's history into a series of time intervals. These time intervals are not equal in length like the hours in a day. Instead the time intervals are variable in length. This is because …

Our site features an interactive, detailed timeline that visually guides you through Earth's eons, eras, periods, and epochs. Beyond the timeline, we offer a suite of powerful practical tools designed for …

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 geological history. …