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, periods, …

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

The geological history of Earth follows the major geological events in Earth's past based on the geologic time scale, a system of chronological measurement based on the study of the planet's rock layers …

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 …

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

Feb 13, 2023 · The answer is the geologic time scale, a system that divides Earth’s history into eons, eras, periods, and epochs. It’s the timeline that connects rocks to time — and time to life.

Rise of civilization and agriculture. Extinction of large mammals in northern hemisphere. Modern humans appear. Four major glaciations cause rapid shifts in ecological communities. Extensive …

May 13, 2025 · The geologic time scale is a system used by scientists to describe Earth's history in terms of major geological or paleontological events (such as the formation of a new rock layer or the …

Jan 11, 2025 · Learn about the geologic time scale or GTS. Discover what it is, how it is divided, and the characteristics of each time period.

The geologic time scale divides up the history of the earth based on life-forms that have existed during specific times since the creation of the planet. These divisions are called geochronologic units (geo: …