Gaskiers Ice Age

from Wikipedia, the free encyclopedia

The Gaskiers Ice Age was an ice age of the Ediacarian approx. 584 to 582 million years ago (according to more recent results, however, already approx. 579 million years ago). It was the last and at the same time the shortest of at least three major ice ages in the era of the Neoproterozoic . Due to its shortness of only 1 to 2 million years (or only approx. 340 thousand years) it is assumed that, in contrast to the Sturtic Ice Age and Marino Ice Age , it did not lead to global glaciation (" Snowball Earth "). Nevertheless, the Gaskier Ice Age also had a major impact on the development of life on earth. It led to the widespread extinction of the first multicellular animal creatures, the acritars . After the end of the Gaskiers Ice Age, the ocean's oxygen levels rose significantly. This rise is considered to be a prerequisite for the appearance of the first complex eukaryotes and the development of the Ediacaran fauna . The first macrofossils of the Ediacaria fauna, the fossils of Charnia , are dated a few million years after the Gaskiers Ice Age or less than 9.5 million years after the Gaskiers Ice Age.

The Gaskiers Ice Age was named after the Gaskiers Formation near Gaskiers in Newfoundland ( Canada ), which is rich in Ice Age rocks from this time. Further evidence of this Ice Age was found in Northern Europe, China, Australia and South America.

Individual evidence

  1. ^ GM Narbonne, S. Xiao, GA Shields: The Geologic Time Scale. Elsevier, 2012, Chapter 18, p. 413.
  2. Jump up ↑ Judy P. Pu, Samuel A. Bowring, Jahandar Ramezani, Paul Myrow, Timothy D. Raub, Ed Landing, Andrea Mills, Eben Hodgin, Francis A. MacDonald: Dodging snowballs: Geochronology of the Gaskiers glaciation and the first appearance of the Ediacaran biota . In: Geology . tape 44 , no. 11 , 2016, p. 955 , doi : 10.1130 / G38284.1 .
  3. ↑ a b Judy P. Pu et al
  4. ↑ DE Canfield, SW Poulton, GM Narbonne: Late-Neoproterozoic deep-ocean oxygenation and the rise of animal life . In: Science . tape 315 , no. 5808 , January 2007, p. 92-95 , doi : 10.1126 / science.1135013 , PMID 17158290 .
  5. ^ S. Xiao, M. Laflamme: On the eve of animal radiation: phylogeny, ecology and evolution of the Ediacara biota . In: Trends Ecol. Evol. (Amst.) . tape 24 , no. 1 , January 2009, p. 31-40 , doi : 10.1016 / j.tree.2008.07.015 .