Cryogenian Period

The Cryogenian Period is the middle period of the Neoproterozoic Era, stretching from. During this period, two major glaciations occurred, the Sturtian and the Marinoan, which were extensive enough to cover the entire surface of the Earth in a snowball Earth scenario. The end of the latter glaciation marked the end of the Cryogenian period.

Before the start of this period, the supercontinent Rodinia had split up, and the continents were drifting apart, closing the Mirovia ocean and forming the Panthallasa ocean.

Adjacent Periods
The Cryogenian Period was preceded by the Tonian Period and succeeded by the Ediacaran Period.