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).

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, …

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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 …

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 …

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 classify …

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

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 …

May 31, 2025 · What is geological time scale? The Geological Time Scale is a chronological system used by geologists and paleontologists to describe the timing and relationships of events that have …

It is a reference and communication system for comparing rocks and fossils from throughout the world and is geology’s equivalent of the periodic table of the elements. The geological time scale is …