Our geologic time scale was constructed to visually show the duration of each time unit. This was done by making a linear time line on the left side of the time columns. Thicker units such as …

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

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, …

At GSA you'll find the resources, confidence, and connections you need to reach fulfilling new heights in your geoscience career.

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.

Table 1 shows some important events in Earth history, presented in the order in which they occurred. The data are also shown on the scale of a calendar year. When geologic time is …

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. …

This timeline shows the Geologic Time Scale with major events. This is a complete, fully interactive timeline chart with 175 geological periods and over 300 events from the formation …