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Precambrian Research, 2012
Abstract China contains three major Precambrian blocks, the North China, South China and Tarim cratons, separated and sutured by Phanerozoic orogenic belts. The North China Craton (NCC) contains rocks as old as 3.8 Ga, but is dominated by Neoarchean igneous rocks that were formed during two magmatic events at 2.8–2.7 Ga and 2.55–2.50 Ga.
Zhao, G, Cawood, PA
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Abstract China contains three major Precambrian blocks, the North China, South China and Tarim cratons, separated and sutured by Phanerozoic orogenic belts. The North China Craton (NCC) contains rocks as old as 3.8 Ga, but is dominated by Neoarchean igneous rocks that were formed during two magmatic events at 2.8–2.7 Ga and 2.55–2.50 Ga.
Zhao, G, Cawood, PA
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Life on Land in the Precambrian
Science, 1994Microfossils have been discovered in cavity-fill and replacement silica that occurs between chert-breccia clasts in 1200-million-year-old paleokarst at the top of the Mescal Limestone, central Arizona, and in ∼800-million-year-old paleokarst at the top of the Beck Spring Dolomite, southeastern California.
R J, Horodyski, L P, Knauth
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Precambrian Research, 1986
Abstract The Subcommission on Precambrian Stratigraphy, consisting at the time of its last formal meeting in 1982 of 12 titular Members and 30 Correspondents, has been actively working toward an acceptable subdivision of Precambrian time for more than a decade.
Kenneth A. Plumb, Harold L. James
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Abstract The Subcommission on Precambrian Stratigraphy, consisting at the time of its last formal meeting in 1982 of 12 titular Members and 30 Correspondents, has been actively working toward an acceptable subdivision of Precambrian time for more than a decade.
Kenneth A. Plumb, Harold L. James
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, 2008 John Carney tells us how two Leicestershire schoolboys were early discoverers of rare Precambrian fossils in the ...
Carney, John, British Geological Survey
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Subdivision of the Precambrian
Geological Society, London, Memoirs, 1985Abstract The Precambrian record is so fragmentary and from such widely contrasting terrains that attempts to erect any formal subdivisions would appear to be premature. The methods that have been used in the Phanerozoic rocks cannot be used for subdividing the Precambrian as they are peculiarly suitable for fossiliferous largely undeformed ...
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Nature, 1963
IN his recent book on The Geological Aspects of the Origin of Life on Earth, Prof. M. G. Rutten has adopted as his central thesis the postulate that the Earth retained its primaeval reducing atmosphere up to 1,500–2,000 million years ago. This conclusion is based on the premise that the gold–uranium ores of the Witwatersrand (South Africa), Blind River
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IN his recent book on The Geological Aspects of the Origin of Life on Earth, Prof. M. G. Rutten has adopted as his central thesis the postulate that the Earth retained its primaeval reducing atmosphere up to 1,500–2,000 million years ago. This conclusion is based on the premise that the gold–uranium ores of the Witwatersrand (South Africa), Blind River
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The Development and Diversification of Precambrian Life
Origins of Life, 1974During the past decade, important strides have been made toward deciphering the paleobiology of the Precambrian Eon, the earliest seven-eighths of Earth history. This progress has accrued chiefly from micropaleontological and organic geochemical studies of fine-grained, ancient cherts.
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A Discussion on the evolution of the Precambrian crust - Crustal development in the Precambrian
Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1973Abstract The oldest Archaean rocks in most shield regions are largely granulites and gneisses, and in west Greenland there is evidence of 1000 Ma of crustal history before the final high-grade metamorphism. Archaean greenstone belts are mostly younger than the high-grade terrains although in some areas, such as southern Africa, this ...
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