AP BIOLOGY

Detailed explanation-1: -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, epochs, and ages.

Detailed explanation-2: -They call it the Geologic Time Scale. It divides Earth’s entire 4.6 billion years into 2 major eons.

Detailed explanation-3: -The geologic time scale is a way of representing deep time based on events that have occurred throughout Earth’s history, a time span of about 4.54 ± 0.05 Ga (4.54 billion years).

Detailed explanation-4: -The geological time scale relates stratigraphy (layers of rock) to periods of time. The time scale is used by geologists, palaeontologists and many other Earth scientists to date certain historical events on Earth.

Detailed explanation-5: -The geologic time scale is divided into (from longest to shortest): eons, eras, periods, epochs and ages.