Archean

Definitions

  • WordNet 3.6
    • adj archean of or relating to the earliest known rocks formed during the Precambrian Eon
    • n Archean the time from 3,800 million years to 2,500 million years ago; earth's crust formed; unicellular organisms are earliest forms of life
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Usage

In literature:

This vast period of time, which includes the beginning, is known among geologists as Archean time.
"The Prehistoric World" by E. A. Allen
We are looking now at the close of the era which geologists call Archean, because it is ancient beyond knowledge.
"The Book of the National Parks" by Robert Sterling Yard
It is the home of the Archean granite, and its basins are of a fathomless dust.
"Whispering Smith" by Frank H. Spearman
The Archean protaxis is sometimes spoken of as a plateau, but probably half of it falls below 1000 ft.
"Encyclopaedia Britannica, 11th Edition, Volume 5, Slice 2" by Various
As regards the life of the Archean, or, as some call it, the "Archeozoic" period, we know nothing.
"Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 4" by Various
Australia is essentially the fragment of a great plateau land of Archean rocks.
"Encyclopaedia Britannica, 11th Edition, Volume 2, Slice 8" by Various
Archean slates and schists.
"North America" by Israel C. Russell
In the geological history of France there have been two great periods of folding since Archean times.
"Encyclopaedia Britannica, 11th Edition, Volume 10, Slice 7" by Various
They are in fact the typical rocks of the Archean (Lewisian, Laurentian, &c.) series.
"Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 2" by Various
At one time these rocks were regarded as Archean gneisses of a special type.
"Encyclopaedia Britannica, 11th Edition, Volume 12, Slice 3" by Various
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In science:

Also depicted are the periods during which glaciations were seen on Earth: The late Archean (3 Gyr) and mid-Proterozoic (2.2-2.4 Gyr BP) which correlate with the previous LMC perigalacticon passage , , and the consequent SFR peak in the MW and LMC.
The Spiral Structure of the Milky Way, Cosmic Rays, and Ice Age Epochs on Earth
Gya rocks.” This puts us smack dab in the Archean.
Astrophysics in 2005
Data gathered from seismic experiments were averaged globally for similar geological and tectonic settings (such as Archean, early Proterozoic, rifts, etc.).
Geo-neutrinos and Earth's interior
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