Middle Jurassic

The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from 176 to 161 million years ago. In European lithostratigraphy, rocks of this Middle Jurassic age are called the Dogger. This name in the past was also used to indicate the Middle Jurassic epoch itself, but is discouraged by the IUGS, to distinguish between rock units and units of geological time.