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Archean Eon |
Also found in: Dictionary/thesaurus, Wikipedia, Hutchinson | 0.01 sec. |
Archean Eonor Archaean Eon or Archeozoic EonOlder of the two divisions of Precambrian time. The Archean begins with the formation of the Earth's crust 4 billion years ago and extends to 2.5 billion years ago, up to the start of the Proterozoic Eon, the second division of the Precambrian Period. The earliest and most-primitive forms of life (bacteria and cyanobacteria) originated more than 3.5 billion years ago in the middle of the Archean Eon (the Archean's alternative name, Archeozoic, means “ancient life”). How to thank TFD for its existence? Tell a friend about us, add a link to this page, add the site to iGoogle, or visit webmaster's page for free fun content. |
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| This northeastern part of the Superior Province, with good exploration potential for gold, base metals and diamond deposits, represents the largest under-explored frontier region of exposed Archean crust in the Canadian Shield. By slowly chipping away at the rock record, however, researchers are starting to develop a portrait of Earth in its tumultuous first 2 billion years, the Archean era. is a rapidly growing gold producer operating in the large Iron Quadrangle Archean greenstone gold camp near Belo Horizonte, which is the mining capital of Brazil. |
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