The geologic time scale (GTS) is a system of chronological dating that classifies geological strata (stratigraphy) in time. It is used by geologists, paleontologists, and other Earth scientists to describe the timing and relationships of events in geologic history.
Scientists use the geologic time scale to illustrate the order in which events on Earth have happened. ... Later, scientists used absolute dating to determine the actual number of years ago that events happened. The geologic time scale is divided into eons, eras, periods, and epochs.
