Archean


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Related to Archean: archaean, Proterozoic

Ar·che·an

also Ar·chae·an  (är-kē′ən)
adj.
1. Of, relating to, or being the older of the two divisions of Precambrian time, from about 3.8 to 2.5 billion years ago, marked by an atmosphere with little free oxygen, the formation of the first rocks and oceans, and the development of unicellular life. See Table at geologic time.
2. Of, relating to, or being the oldest known rocks, those of the Precambrian Eon, that are predominantly igneous in composition.
n.
The Archean Eon. Also called Archeozoic.

[From Greek arkhaios, ancient; see archaic.]

Archean

(ɑːˈkiːən)
adj
(Geological Science) a variant spelling (esp US) of Archaean

Ar•che•an

(ɑrˈki ən)

adj.
of or pertaining to rocks of the Archeozoic portion of the Precambrian Era.
[1870–75]

Ar·che·an

(är-kē′ən)
The earlier of the two divisions of the Precambrian Eon, from about 3.8 to 2.5 billion years ago. During this time, the Earth had an atmosphere with little free oxygen, and the first single-celled life appeared. See Chart at geologic time.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.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
Precambrian, Precambrian aeon, Precambrian eon, Precambrian period - the eon following the Hadean time and preceding the Phanerozoic eon; from about 3,800 million years ago until 544 million years ago
Adj.1.archean - of or relating to the earliest known rocks formed during the Precambrian Eon
geology - a science that deals with the history of the earth as recorded in rocks
early - at or near the beginning of a period of time or course of events or before the usual or expected time; "early morning"; "an early warning"; "early diagnosis"; "an early death"; "took early retirement"; "an early spring"; "early varieties of peas and tomatoes mature before most standard varieties"
Translations
References in periodicals archive ?
In July, KKR placed finance in Chennai-based Archean Salt Holdings, worth INR 135 crore.
TEHRAN (FNA)- Earth's mantle temperatures during the Archean eon, which commenced some 4 billion years ago, were significantly higher than they are today.
Life evolved on Earth during the Archean, between 3.
Evidence of the paradox comes from clues in the rock record that indicate the presence of flowing water as far back as the Archean eon, 3.
Ameyo, empowers customer interaction management of Archean Design and Development, a real estate venture based in Chennai that provides luxury homes catering to the modern lifestyle.
The Pearl Industrial Chemicals Company (PIC) has been established by Bahrain's EBH Holding and India's Archean Group of Companies.
The plant, when fully operational, is expected to produce 60,000 metric tonnes of aluminium fluoride, which is a critical chemical ingredient in the aluminium smelting process, said Chennai-based Archean Group executive director C G Sethuram.
Komatiites are ultramafic volcanic rocks that occur mainly in Archean and Paleoproterozoic greenstone belts.
Over 23% of the world's Archean rocks are comprised of rocks of the Superior Craton.
this second $200,000 payment by Archean Group to commence construction of the 1:10 scale pilot plant will help validate Clean Coal Technologies' patented process to create a cleaner burning fuel.
Sika Resources controlled properties contain Archean greenstone rocks that have numerous northeast-southwest and northwest-southeast trending fault/shear zones, which are similar to other known gold deposits across the Lake Victoria region.