Zircon U-Pb
Provenance and age delimitation of Quadrila´tero Ferrı´fero sandstones based on zircon U–Pb isotopes
... metamorphic zircon and present in two preserved metamorphic rims (sample 2, grain b32; sample 5, grain b8; Table ...dated zircon crystals are magmatic, because the Th/U ratios are greater than ...
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Tectonic evolution of the southern margin of the Amazonian craton in the late Mesoproterozoic based on field relationships and zircon U-Pb geochronology
... New U-Pb zircon geochronological data integrated with field relationships and an airborne geophysical survey suggest that the Nova Brasilândia and Aguapeí belts are part of the same monocyclic, ...
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Metamorphic evolution and U-Pb zircon SHRIMP geochronology of the Belizário ultramafic amphibolite, Encantadas Complex, southernmost Brazil
... and zircon U-Pb SHRIMP geochronology of the Belizário ultramafic amphibolite from southernmost Brazil leads to a better understanding of the processes involved in the generation of the Encantadas ...
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Intracratonic Palaeoproterozoic granitoids in northern Finland: prolonged and episodic crustal melting events revealed by Nd isotopes and U-Pb ages on zircon
... Deepening of the sedimentary basin caused accu- mulation of more fine-grained sediments represent- ed by phyllites and black schists, belonging to the Sa- vukoski Group. These pelitic metasediments are con- formably ...
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Braz. J. Geol. vol.47 número4
... provided zircon U-Pb ages of 579 ± 13 Ma and 569 ± ...by U-Pb LA-ICP-MS method in lapilli-tufs previously con- sidered as part of the AVF, is ...the U-Pb zircon ...
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Braz. J. Geol. vol.47 número2
... 1.1). Zircon U-Pb data pro- vided consistent ages of 2165 ± 7 Ma, 2170 ± 7 Ma, 2170 ± 7 Ma, 2161 ± 4 Ma and 2175 ± 8 Ma, dating emplacement of these gran- itoids as Paleoproterozoic ...
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Brazilian Journal of Geology
... 1.1). Zircon U-Pb data pro- vided consistent ages of 2165 ± 7 Ma, 2170 ± 7 Ma, 2170 ± 7 Ma, 2161 ± 4 Ma and 2175 ± 8 Ma, dating emplacement of these gran- itoids as Paleoproterozoic ...
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Protolith age of Santa Maria Chico granulites dated on zircons from an associated amphibolite-facies granodiorite in southernmost Brazil
... of zircon SHRIMP U-Pb ages was obtained by Hartmann et ...Archean zircon U-Pb ion microprobe age ...magmatic zircon during a granulite facies growth ...
9
REPOSITORIO INSTITUCIONAL DA UFOP: U–Pb ages and Hf-isotope data of detrital zircons from the late Neoarchean-Paleoproterozoic Minas Basin, SE Brazil.
... and U mineralizations, the late Neoarchean to Paleoproterozoic Minas Basin (Minas Supergroup, SE of Brazil) is one of the best-studied basins in South ...detrital zircon U– Pb age patterns ...
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Zircon ages delimit the provenance of a sand extrudite from the Botucatu Formation in the Paraná volcanic province, Iraí, Brazil
... detrital zircon crystals from a sand extrudite, Cretaceous Paraná volcanic province, set limits on the origin of the numerous sand layers present in this major flood basalt ...The zircon U-Pb ...
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A proveniência dos sedimentos e cinzas vulcânicas dos sedimentos Permianos da Bacia do Paraná: implicações para a história geológica do sul-sudoeste de Gondwana
... present U-Pb and Lu-Hf detrital zircon data and whole rock Sm-Nd isotope data for samples across the ...profile. Zircon U-Pb data of the lower to middle part of the Permian (Rio ...
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REPEATED PARTIAL MELTING EVENTS IN POLYMETAMORPHIC CARLOS CHAGAS BATHOLITH: IMPLICATIONS FOR TECTONO- METAMORPHIC EVOLUTION OF THE ARAÇUAÍ OROGEN, SOUTHEASTERN BRAZIL
... Detrital zircon U-Pb data of the quartzites indicates five main peaks at ...youngest zircon population indicate maximum sedimentation age around 900 Ma (Gonçalves-Dias et ...similar ...
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Age of pegmatites from eastern Brazil and implications of mica intergrowths on cooling rates and age calculations
... The Rio Doce valley in the Governador Valadares region comprises rocks such as gneisses, a supracrustal schist sequence, sericite quartzite, and intrusive granitoids (Almeida, 1981; Cunningham et al., 1996; Oliveira et ...
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U –Pb ages of shocked zircon grains link distal K–Pg boundary sites in Spain and Italy with the Chicxulub impact
... In the present study, individual shocked zircon from the K–Pg clay layer in Spain and Italy again indicates a dominant Pan-African source age of 549.5 Ma, indistinguishable from the ages determined in those ...
8
Polímeros vol.8 número2
... Embora os valores de Ts tenham sido na mesma ordem de grandeza, 63,1°C, 68,9°C, 80,5°C, 80,5°C e 86°C, a atividade hidrolítica da colagenase só foi observada para PB tratados com uma concentração de GA de até ...
9
Repositório Institucional da UFPA: Geology, Geochemistry, and Geochronology (U-Pb) of the Rio Fortuna Gneiss - Serra do Baú Intrusive Suite - Paraguá Terrane - SW Amazonian Craton
... The rocks in this unit are of a slightly expanded acidic nature, with SiO 2 values between 67.17 and 75.76%. The Harker diagrams (Fig. 5) show coherent variation trends, with negative linear correlations between silica ...
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REPOSITORIO INSTITUCIONAL DA UFOP: U-Pb geochronology of the Lagoa Real uranium district, Brazil : implications for the age of the uranium mineralization.
... date zircon and titanite grains from the S~ao Timoteo granitoid, and albite-rich rocks from the Lagoa Real district in order to assess the age of granite emplacement, defor- mation/metamorphism and uranium ...
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U-Pb dating by zircon dissolution method using chemical abrasion
... for U-Pb dating prior to analyses using in situ Laser Ablation-MultiCollector Ion Coupled Plasma Mass Spectrometer (LA-ICPMS) followed by the Isotope Dissolution Thermal Ionization Mass Spectrometer ...
7
New U-Pb SHRIMP zircon ages for pre-variscan orthogneisses from Portugal and their bearing on the evolution of the Ossa-Morena Tectonic Zone
... SHRIMP U-Pb zircon ages for the Portalegre and Alcáçovas orthogneisses document a complex pre- Variscan history for the Iberian basement in ...
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Repositório Institucional da UFPA: Evolução geológica da porção centro-sul do Escudo Guianas com base no estudo geoquímico, geocronológico (evaporação de Pb e U-Pb ID-TIMS em zircão) e isótopo (Nd-Pb) dos granitóides paleoproterozóicos do sudeste de Rorai
... Hornblenda e biotita (meta)granitóides, milonitos, leucognaisses e granulitos, com estruturas preferencialmente NE-SW e E-W, ocorrem no Domínio Güiana Central (DGC), próximo do limite com o Domínio Uatumã-Anauá (DUA), ...
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