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U-Pb ages and Hf isotope compositions of zircons in plutonic rocks from the central Famatinian arc, Argentina
(Pergamon-Elsevier Science Ltd, 2017-07)
The Famatinian arc formed around the South Iapetus rim during the Ordovician, when oceanic lithosphere subducted beneath the West Gondwana margin. We present combined in situ U–Th–Pb and Lu–Hf isotope analyses for zircon ...
A combined zircon Hf isotope and whole-rock Nd and Sr isotopes study of Carboniferous A-type granites, Sierras Pampeanas of Argentina
(Pergamon-Elsevier Science Ltd, 2020-06)
We report new whole-rock Nd and Sr isotope data for two strongly peraluminous and one slightly peraluminous Carboniferous A-type granitic plutons in the eastern Sierras Pampeanas of Argentina. Our study also integrates ...
Lu-Hf ratios of crustal rocks and their bearing on zircon Hf isotope model ages: The effects of accessories
(Elsevier Science, 2018-05)
All other factors being equal, the calculation of zircon Hf two stage model ages (T DM Hf) depends on the particular Lu/Hf value assumed for the magmatic source, the effect being more pronounced as the age difference between ...
Zircon O- and Hf-isotope constraints on the genesis and tectonic significance of Permian magmatism in Patagonia
(Geological Soc Publ House, 2017-09)
The genesis of Permian magmatism in southern South America is actively debated, particularly in relation to the origin of Patagonia. U-Pb zircon ages of c. 255 Ma for igneous rocks from the basement of Tierra del Fuego are ...
The petrogenesis of back-arc magmas, constrained by zircon O and Hf isotopes, in the Frontal Cordillera and Precordillera, Argentina
(Springer, 2020-08-29)
The Andean margin of the South American continent has been magmatically and tectonically active for over 330 million years. It is the type location where “Cordilleran-type” magmatism and orogenesis are manifest. In Argentina ...
The Malvinas (Falkland) Islands revisited: The tectonic evolution of southern Gondwana based on U-Pb and Lu-Hf detrital zircon isotopes in the Paleozoic cover
(Pergamon-Elsevier Science Ltd, 2017-07)
The first U-Pb and Hf-Lu isotopic data of detrital zircons from Devonian strata of the Malvinas (Falkland) Islands allow re-evaluation of different hypotheses regarding their location before the breakup of Gondwana. Of the ...
Barren Miocene granitoids in the Central Andean metallogenic belt, Chile: Geochemistry and Nd-Hf and U-Pb isotope systematics
(Servicio Nacional de Geología y Minería (SERNAGEOMIN), 2010)
In situ isotopic analyses of U and Pb in zircon by remotely operated SHRIMP II, and Hf by LA-ICP-MS: an example of dating and genetic evolution of zircon by 176Hf/177Hf from the Ita quarry in the Atuba Complex, SE BrazilAnálises in situ de U e Pb em zircão por SHRIMP II por controle remoto e de Hf por LA-ICP-MS: um exemplo de datação e da evolução genética de zircão através da razão 176Hf/177Hf em amostra da pedreira Ita no Complexo Atuba, SE Brasil
(Universidade de São Paulo, Instituto de Geociências, 2009)
Archean crustal evolution in the Southern São Francisco craton, Brazil: constraints from U-Pb, Lu-Hf and O isotope analyses
(Elsevier Science, 2016-12)
In this study we present U–Pb and Hf isotope data combined with O isotopes in zircon from Neoarchean granitoids and gneisses of the southern São Francisco craton in Brazil. The basement rocks record three distinct magmatic ...