Timeline of glaciation

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Climate history over the past 500 million years, with the last three major ice ages indicated, Andean-Saharan (450 Ma), Karoo (300 Ma) and Late Cenoizic. A less severe cold period or ice age is shown during the Jurassic-Cretaceous (150 Ma).

There have been five or six major ice ages in the history of Earth over the past 3 billion years. The Late Cenozoic Ice Age began 34 million years ago, its latest phase being the Quaternary glaciation, in progress since 2.58 million years ago.

Within ice ages, there exist periods of more severe glacial conditions and more temperate referred to as glacial periods and interglacial periods, respectively. The Earth is currently in such an interglacial period of the Quaternary glaciation, with the last glacial period of the Quaternary having ended approximately 11,700 years ago, the current interglacial being known as the Holocene epoch.[1] Based on climate proxies, paleoclimatologists study the different climate states originating from glaciation.

Known ice ages[edit]

Major known ice ages shown in blue.

Name Period (Ma) Period Era
Pongola 2900 – 2780[2] Mesoarchean
Huron 2400 – 2100 Siderian
Rhyacian
Paleoproterozoic
Sturt
Marino
Gaskiers
Baykonur
715 – 680
650 – 635
580
547
Cryogenian

Ediacaran
Neoproterozoic
Andean-Saharan
(incl. Hirnantian and Late Ordovician glaciation in general)
450 – 420 Late Ordovician
Silurian
Paleozoic
Karoo 360 – 260 Carboniferous
Permian
Paleozoic
Late Cenozoic Ice Age
(incl. Quaternary glaciation)
34 – present Late Paleogene (Oligocene)
Neogene
Quaternary
Cenozoic


1010

Precambrian " "
Hadean Archean Proterozoic Phane
Eo- Paleo- Meso- Neo- Paleo- Meso- Neo- P M C
9 8 7 6 5 4 3 2 1

109

Proterozoic Phanerozoic
Neoproterozoic Paleozoic Mesozoic Cenozoic
Tonian Cryogenian Ediacaran Cambr Ordov Si Devon Carbon Permi Trias Juras Creta P-gene
9 8 7 6 5 4 3 2 1

108

Mesozoic Cenozoic
Cretaceous Paleogene Neogene Quat
Late Paleocene Eocene Oligocene Miocene Plio
9 8 7 6 5 4 3 2 1

107

Neogene Quaternary
Miocene Pliocene Pleistocene
Tortonian Messinian Zanclean Piacenzia Gelasian Calabrian Ionian
9 8 7 6 5 4 3 2 1

106

Pleistocene
Calabrian Ionian Tarantian
9 8 7 6 5 4 3 2 1

105

Pleistocene Subatlantic
9 8 7 6 5 4 3 2 1

104

9 8 7 6 5 4 3 2 1

Descriptions[edit]

The third ice age, and possibly most severe, is estimated to have occurred from 720 to 635 Ma (million years) ago,[3] in the Neoproterozoic Era, and it has been suggested that it produced a second[4] "Snowball Earth", in which the Earth iced over completely. It has been suggested also that the end of this second cold period[4] was responsible for the subsequent Cambrian Explosion, a time of rapid diversification of multicelled life during the Cambrian Period. However, this hypothesis is still controversial,[5][6] though is growing in popularity among researchers, as evidence in its favor has mounted.[who?]

A minor series of glaciations occurred from 460 Ma to 430 Ma. There were extensive glaciations from 350 to 250 Ma.

The Late Cenozoic Ice Age has seen extensive ice sheets in Antarctica for the last 34 Ma. During the last 3 Ma ice sheets have also developed on the northern hemisphere. This phase is known as the Quaternary glaciation, and has seen more or less extensive glaciation on 40,000 and later, 100,000 year cycles.

Nomenclature of Quaternary glacial cycles[edit]

Whereas the first 30 million years of the Late Cenozoic Ice Age mostly involved Antarctica, the Quaternary has seen numerous ice sheets extending over parts of Europe and North America that are currently populated and easily accessible. Early geologists therefore named apparent sequences of glacial and interglacial periods of the Quaternary Ice Age after characteristic geological features, and these names varied from region to region. It is now more common for researchers to refer to the periods by their marine isotopic stage number.[7] 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.[8] The names system has mostly been phased out by professionals, who instead use the marine isotopic stage indexes for all technical discussions. 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).[9]

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.[8]

Historical nomenclature in the Alpes[edit]

Historical nomenclature in Great Britain and Ireland[edit]

Historical nomenclature in Northern Europe[edit]

Historical nomenclature in North America[edit]

Historical nomenclature in South America[edit]

Uncertain Correlations[edit]

It has proved difficult to correlate the traditional regional names with the global marine and ice core sequences. The indexes of MIS often identify several distinct glaciations that overlap in time with a single traditional regional glaciation. Some modern authors use the traditional regional glacial names to identify such a sequence of glaciations, whereas others replace the word “glaciation” with “complex” to refer to a continuous period of time that also includes warmer stages. As shown in the table below, it is only during the last 200-300 thousand years that the time resolution of the traditional nomenclature allow for direct correspondence with MIS indexes.

Marine
isotope
stage
Period (ka)
[11]
Historical regional names
Alpine region Great Britain N. Europe N. America S. America
MIS 19 790-761 AC AC AC Pre-illinois
MIS 18 761-712 AC AC AC Pre-illinois
MIS 17 712-676 AC AC AC Pre-illinois
MIS 16 676-621 AC AC AC Pre-illinois
MIS 15 621-563 AC Cromer? Cromer? Pre-illinois
MIS 14 563-533 AC Cromer? Cromer? Pre-illinois
MIS 13 533-478 AC Cromer? Cromer? Pre-illinois
MIS 12 478-424 Mindel? Anglia? Elster? Pre-illinois
MIS 11 424-374 AC Hoxne? AC Pre-illinois
MIS 10 374-337 Mindel? Anglia? Elster? Pre-illinois
MIS 9 337-300 Mindel-Riss? Hoxne? Holstein? Pre-illinois
MIS 8 300-243 Riss? Wolston Saale? Illinois?
MIS 7 243-191 AC Wolston AC AC
MIS 6 191-130 Riss Wolston Saale Illinois
MIS 5e 123 (peak) Riss-Würm Ipswich Eem Sangamon Valdivia
MIS 5d 109 (peak) AC Devens/Early D.[12] Weichsel/Herning[13] AC AC
MIS 5c 96 (peak) AC Devens/Early D.[12] Weichsel/Brørup[13] AC AC
MIS 5b 87 (peak) AC Devens/Early D.[12] Weichsel/Rederstall[13] AC AC
MIS 5a 82 (peak) AC Devens/Early D.[12] Weichsel/Odderade[13] AC AC
MIS 4 71-57 Würm Devens/Middle D.[12] Weichsel/Middle W.[13] Wisconsin Llanquihue
MIS 3 57-29 Würm Devens/Middle D.[12] Weichsel/Middle W.[13] Wisconsin Llanquihue
MIS 2 29-14 Würm/LGM Devens/Dimlington Weichsel/LGM Wisconsin/Vashon Llanquihue/LGM
MIS 1 14-present (Holocene) Flandria (Holocene) (Holocene) (Holocene)
Table explanation
Extensive interglacial (similar to Holocene)
Moderate interglacial
Intermediate climate
Moderate glaciation
Extensive glaciation (similar to LGM)
AC = Ambigous correlation

Sources[edit]

For sources to the tables, see the individual linked articles.

See also[edit]

References[edit]

  1. ^ Walker, M., Johnsen, S., Rasmussen, S. O., Popp, T., Steffensen, J.-P., Gibbard, P., Hoek, W., Lowe, J., Andrews, J., Bjo¨ rck, S., Cwynar, L. C., Hughen, K., Kershaw, P., Kromer, B., Litt, T., Lowe, D. J., Nakagawa, T., Newnham, R., and Schwander, J. 2009. Formal definition and dating of the GSSP (Global Stratotype Section and Point) for the base of the Holocene using the Greenland NGRIP ice core, and selected auxiliary records. J. Quaternary Sci., Vol. 24 pp. 3–17. ISSN 0267-8179.
  2. ^ Robert E. Kopp; Joseph L. Kirschvink; Isaac A. Hilburn & Cody Z. Nash (2005). "The Paleoproterozoic snowball Earth: A climate disaster triggered by the evolution of oxygenic photosynthesis". Proc. Natl. Acad. Sci. U.S.A. 102 (32): 11131–6. Bibcode:2005PNAS..10211131K. doi:10.1073/pnas.0504878102. PMC 1183582. PMID 16061801.
  3. ^ "Chart". International Commission on Stratigraphy. Archived from the original on 2017-01-13. Retrieved 2017-02-14.
  4. ^ a b Miracle Planet: Snowball Earth, (2005) documentary, Canadian Film Board, rebroadcast 25 April 2009 on the Science Channel (HD).
  5. ^ van Andel, Tjeerd H. (1994). New Views on an Old Planet: A History of Global Change (2nd ed.). Cambridge UK: Cambridge University Press. ISBN 0-521-44755-0.
  6. ^ Rieu, Ruben; et al. (2007). "Climatic cycles during a Neoproterozoic "snowball" glacial epoch". Geology. 35 (4): 299–302. Bibcode:2007Geo....35..299R. doi:10.1130/G23400A.1. Archived from the original on 2012-05-16.
  7. ^ Gibbard, P.; van Kolfschoten, T. (2004). "Chapter 22: The Pleistocene and Holocene Epochs" (PDF). In Gradstein, F. M.; Ogg, James G.; Smith, A. Gilbert. A Geologic Time Scale 2004. Cambridge: Cambridge University Press. ISBN 0-521-78142-6.
  8. ^ a b Davis, Owen K. "Non-Marine Records: Correlations with the Marine Sequence". Introduction to Quaternary Ecology. University of Arizona. Archived from the original on 2017-07-27.
  9. ^ Kukla, George (August 2005). "Saalian supercycle, Mindel/Riss interglacial and Milankovitch's dating". Quaternary Science Reviews. 24 (14–15): 1573–83. Bibcode:2005QSRv...24.1573K. doi:10.1016/j.quascirev.2004.08.023.
  10. ^ https://www.britannica.com/science/Menapian-Glacial-Stage
  11. ^ Lisiecki, Lorraine E.; Raymo, Maureen E. (2005). "A Pliocene-Pleistocene stack of 57 globally distributed benthic δ18O records". Bibcode:2005PalOc..20.1003L. doi:10.1029/2004PA001071.
  12. ^ a b c d e f Delaney, Catherine (2003). "The Last Glacial Stage (the Devensian) in Northwest England" (PDF). North West Geography. 3 (2): 27–37. ISSN 1476-1580.
  13. ^ a b c d e f Lokrantz, Hanna; Sohlenius, Gustav (2006). Ice marginal fluctuations during the Weichselian glaciation in Fennoscandia, a literature review (Technical Report TR-06-36) (PDF). Stockholm: Svensk Kärnbränslehantering AB (Swedish Nuclear Fuel and Waste Management Co).

External links[edit]

The dictionary definition of glaciation at Wiktionary