Kaigas

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Events of the Cryogenian Period
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First sponge-like animal.[2]
Kaigas glaciation?[3]

Kaigas is the hypothesized first major glaciation or snowball earth in the Cryogenian period of the Neoproterozoic Era. During the Kaigas, almost the entire earth was covered with ice sheets up to more than a kilometer thick.[5]

Geological context[edit]

The ice age was first identified in stratigraphic units in Namibia and sedimentary evidence for the glaciation is not seen in the South China Block where other Neoproterozoic snowball earth glactions are identified from the sedimentary record. Instead, the presence of the Kaigas on the South China Block is identified through stable isotope evidence.[6]

References[edit]

  1. ^ a b Arnaud, E.; Halverson, G. P.; Shields-Zhou, G. (30 November 2011). "Chapter 1 The geological record of Neoproterozoic ice ages". Geological Society, London, Memoirs 36 (1): 1–16. doi:10.1144/M36.1. 
  2. ^ Brain, C. K., Prave, A. R., Hoffmann, K. H., Fallik, A. E., Herd D. A., Sturrock, C., Young, I., Condon, D. J., Allison, S. G. (2012). "The first animals: ca. 760-million-year-old sponge-like fossils from Namibia". S. Afr. J. Sci. 108 (8): 1–8. doi:10.4102/sajs.v108i1/2.658. 
  3. ^ Macdonald, F. A.; Schmitz, M. D.; Crowley, J. L.; Roots, C. F.; Jones, D. S.; Maloof, A. C.; Strauss, J. V.; Cohen, P. A.; Johnston, D. T.; Schrag, D. P. (4 March 2010). "Calibrating the Cryogenian". Science 327 (5970): 1241–1243. doi:10.1126/science.1183325. PMID 20203045.  (Duration and magnitude are enigmatic)
  4. ^ "Discovery of possible earliest animal life pushes back fossil record". phys.org. Retrieved 7 December 2012. 
  5. ^ "Chinese Science Bulletin, Volume 54, Number 10". SpringerLink. Retrieved 2012-09-08. 
  6. ^ Zhang, QiRui, XueLei Chu, LianJun Feng. Discussion on the Neoproterozoic glaciations in the South China Block and their related paleolatitudes. 2009 Chinese Science Bulletin 54(10):1797-1800.