Produção Nacional
Guyana: the Lost Hadean crust of South America?
2013; Sociedade Brasileira de Geologia; Volume: 43; Issue: 4 Linguagem: Inglês
10.5327/z2317-48892013000400002
ISSN2317-4889
AutoresSerge Nadeau, Chen Wei, Jimmy Reece, Deokumar Lachhman, Randy Ault, Maria Telma Lins Faraco, Lêda Maria Barreto Fraga, Nélson Joaquim Reis, Léandro Menezes Betiollo,
Tópico(s)Paleontology and Stratigraphy of Fossils
ResumoA Hadean zircon xenocryst with a U-Pb zircon age of 4,219 ± 19 Ma, along with several zircon xenocrysts of Archean age (ca.2,510 to 3,811 Ma) were found in a rock of the Paleoproterozoic Iwokrama Formation, which includes felsic volcanics and co-magmatic granitic intrusions.It demonstrates the existence of an underlying "Lost Hadean Crust", representing the oldest crustal component of the Guiana Shield.Detrital zircons of late Archean age, up to 2,700 Ma, are also present in the high-grade rocks of the Kanuku Complex, located to the south, and may be derived from the same Hadean-Archean crustal block.
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