The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies, paleomagnetic properties, and fossils.

Dec 1, 2025 · It subdivides all time into named units of abstract time called—in descending order of duration— eons, eras, periods, epochs, and ages. The enumeration of those geologic time …

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

Each eon, era, period, and epoch is defined by major geological or paleontological events. The eons are the Hadean, Archean, Proterozoic, and Phanerozoic. The Phanerozoic Eon is 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.

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.

May 13, 2025 · Scientists use the geologic time scale to organize Earth's long history into eons, eras, and periods. The Phanerozoic eon is known for the appearance and dominance of …

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. …

These are further divided into Eras, which are divided into periods, which are still divided further in Epochs. Geologists do this to be precise about the time in which a geologic event occurs. …

In addition to the relative dating of periods in Earth's history for which we have rocks preserved, geologists are now able to assign absolute age dates to critical intervals.