A minor series of glaciations occurred from 460 Ma to 430 Ma. There were extensive glaciations from 350 to 250 Ma. The current ice age, called the Quaternary glaciation, has seen more or less extensive glaciation on 40,000 and later, 100,000 year cycles. We are currently in an interglacial period, as the last glacial period ended about 10,000 years ago.
|30 - present||Neogene||Cenozoic|
|Karoo||360 - 260||Carboniferous and Permian||Paleozoic|
|Andean-Saharan||450 - 420||Ordovician and Silurian||Paleozoic|
|800 - 635||Cryogenian||Neoproterozoic|
|Huronian glaciation||2100 - 2400||Siderian and Rhyacian||Paleoproterozoic|
Originally, the periods were named after characteristic geological features, and these names varied from region to region. It is now more common to refer to periods by their marine isotopic stage number. The marine record preserves all the past glaciations; the land-based evidence is less complete because successive glaciations may wipe out evidence of their predecessors. Ice cores from continental ice accumulations also provide a complete record, but do not go as far back in time as marine data. Pollen data from lakes and bogs as well as loess profiles provided important land-based correlation data. The names system has not been completely filled out since the technical discussion moved to using marine isotopic stage numbers. For example, there are five Pleistocene glacial/interglacial cycles recorded in marine sediments during the last half million years, but only three classic interglacials were originally recognized on land during that period (Mindel, Riss and Würm).
Land-based evidence works acceptably well back as far as MIS 6, but it has been difficult to coordinate stages using just land-based evidence before that. Hence, the "names" system is incomplete and the land-based identifications of ice ages previous to that are somewhat conjectural. Nonetheless, land based data is essentially useful in discussing landforms, and correlating the known marine isotopic stage with them.
|Alpine||N. American||N. European||Great Britain||S. American|
|Flandrian||interglacial||present – 12||1||Holocene|
|Devensian||Llanquihue||glacial period||12 – 110|| 2-4|
|Riss-Würm||Sangamon||Eemian||Ipswichian||interglacial||110 – 130||5e|
|2nd||Riss||Illinoian||Saale||Wolstonian or Gipping||Santa María||glacial period||130 – 200||6|
|Mindel-Riss||Yarmouth||Holstein||Hoxnian||interglacial(s)||200 – 300/380||7,9,11|
|3rd – 5th||Mindel||Kansan||Elsterian||Anglian||Río Llico||glacial period(s)||300/380 – 455||8,10,12|
|Günz-Mindel||Aftonian||Cromerian*||interglacial(s)||455 – 620||13-15|
|7th||Günz||Nebraskan||Menapian||Beestonian||Caracol||glacial period||620 – 680||16|
Older periods of the Pleistocene
|Pastonian Stage||interglacial||600 – 800|
|Pre-Pastonian Stage||glacial period||800 – 1300|
|Bramertonian Stage||interglacial||1300 – 1550|
**Table data is based on Gibbard Figure 22.1.
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