There have been four major periods of glaciation in the Earth's past. The first, and possibly most severe, may have occurred from 800 to 600 million years ago (the late Proterozoic Age) and it has been suggested that it produced a Snowball Earth in which the earth iced over completely. It has been suggested also that the end of this cold period was responsible for the subsequent Cambrian Explosion — this theory is recent and controversial.
A minor series of glaciations occurred from 460 to 430 million years ago. There were extensive glaciations from 350 million years before present to 250 million. The present Pleistocene ice age has seen more or less extensive glaciation on 40,000 and 100,000 year cycles. The last glacial period ended about 10,000 years ago.
| Name
| Inter/Glacial
| Period
| Geologic era
|
Wisconsinan /
Weichsel or Vistula
| glacial period, | 15 – 70
| Quaternary
|
| Sangamon / Eemian
| interglacial, | 70 – 130
|
| Illinoian / Saale
| glacial, | 130 – 180
|
| Yarmouth / Holstein
| interglacial, | 180 – 230
|
| Kansan / Elster
| glacial, | 230 – 300
|
| Aftonian / Cromer
| interglacial, | 300 – 330
|
| Nebraskan / Gunz
| glacial, | 330 – 470
|
| — / Waalian
| interglacial, | 470 – 540
|
| — / Donau II
| glacial, | 540 – 550
|
| — / Tiglian
| interglacial, | 550 – 585
|
| — / Donau I
| glacial, | 585 – 600
|
|
| glacial
| 250-350 Myr
| Devonian, Carboniferous, Permian
|
|
| glacial
| 430-460 Myr
| Ordovician
|
| Sturtian-Varangian (or cryogene)
| glacial
| 650-900 Myr
| late Proterozoic
|
See also
