Earth Geology Geologic Time Scale Tertiary Period

Tertiary Period

The Tertiary time period lasted from 65 to 1.8 million years ago, a time span of 63 million years. The Tertiary Period is the first part of the Cenozoic Era. The term Tertiary was first used in the 1760s to describe the uppermost of a three part division of the rocks in the mountains of northern Italy. These Tertiary rocks were defined based on a particular type of fossil assemblage contained within them. They are located above the rocks of the Cretaceous System and below the rocks of the Quaternary System.