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	Provedor de dados Anais da ABC (AABC) (4) Autor Hartmann,Léo A. (4) Leite,Jayme A.D. (2) Santos,João O.S. (2) Bastos-Neto,Artur C. (1) Chemale Júnior,Farid (1) Dussin,Ivo A. (1) Jelinek,Andréa R. (1) Kawashita,Koji (1) Liu,Dunyi (1) Massonne,Hans-Joachim (1) McNaughton,Neal J. (1) Mcnaughton,Neal J. (1) Porcher,Carla C. (1) Takehara,Lucy (1) Wang,Yenbin (1) Mais... Palavra-chave SHRIMP (2) Zircon geochronology (2) Chemical abrasion (1) Encantadas Complex (1) Fluorite (1) Geochronology (1) ID-TIMS (1) LA-MC-ICPMS (1) Metamorphism (1) Paleoproterozoic (1) Pedras Grandes Suite (1) Protolith age (1) Santa Maria Chico Granulitic Complex (1) Trans-Amazonian Cycle (1) U-Pb dating (1) Ultramafic amphibolite (1) Zircon (1) Zircon dissolution (1) Mais... Tipo do documento Info:eu-repo/semantics/article (3) Info:eu-repo/semantics/other (1) Ano 2012 (1) 2008 (1) 2005 (1) 2003 (1) País Brazil (4) Idioma Inglês (4)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 4 Primeira ... 1 ... Última U-Pb dating by zircon dissolution method using chemical abrasion Anais da ABC (AABC) Takehara,Lucy; Chemale Júnior,Farid; Hartmann,Léo A.; Dussin,Ivo A.; Kawashita,Koji. Chemical abrasion was carried out on zircons grains of the Temora II standard 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 (ID-TIMS) method. The proposed methodology was herein applied in order to reduce primarily the effects of secondary Pb loss, the presence of common lead and/or silicate impurities. Nine Temora II zircon grains were analyzed by the laser ablation method yielding an age of 418.3±4.3 Ma. Zircon grains of a same population were separated for chemical abrasion before dissolution and mass spectrometry analyses. Six fractions of them were separated for isotope dissolution using 235U-205Pb... Tipo: Info:eu-repo/semantics/other Palavras-chave: Chemical abrasion; ID-TIMS; LA-MC-ICPMS; U-Pb dating; Zircon dissolution. Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000200011 Protolith age of Santa Maria Chico granulites dated on zircons from an associated amphibolite-facies granodiorite in southernmost Brazil Anais da ABC (AABC) Hartmann,Léo A.; Liu,Dunyi; Wang,Yenbin; Massonne,Hans-Joachim; Santos,João O.S.. U-Pb dating of zircon was undertaken with the Beijing SHRIMP II (sensitive high resolution ion microprobe) on anamphibolite facies granodiorite and an almandine-albite granulite from the Santa Maria Chico Granulitic Complex, southern Brazilian Shield. This work was also done to unravel protolith ages which are often hidden in the array of partly reset data. The obtained metamorphic ages of the granodiorite gneiss and the granulite are 2035 ± 9 Ma and 2006 ± 3 Ma, respectively. These data are within the range of metamorphic ages determined in previous studies (2022 ± 18 Ma and 2031 ± 40 Ma). However, protolith ages for the granodiorite (2366 ± 8 Ma) and the granulite (2489 ± 6 Ma) were obtained which are outside the previously recognized range (>... Tipo: Info:eu-repo/semantics/article Palavras-chave: Protolith age; Paleoproterozoic; Zircon geochronology; Santa Maria Chico Granulitic Complex; SHRIMP. Ano: 2008 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652008000300014 SHRIMP U-Pb zircon dating of Pedras Grandes Suite, southern Santa Catarina State, Brazil Anais da ABC (AABC) Jelinek,Andréa R.; Bastos-Neto,Artur C.; Leite,Jayme A.D.; Hartmann,Léo A.; McNaughton,Neal J.. Two major magmatic pulses of the granitic Florianópolis Batholith in Santa Catarina State, southern Brazil, occurred between 613±5Ma and 595±5 Ma, during the Neoproterozoic Brasiliano Cycle. These ages were obtained by U-Pb isotopic determinations with the sensitive high mass-resolution ion microprobe on igneous zircons from Pedras Grandes Suite in Santa Catarina State. Euhedral zircons remained unaltered close to a fluorite vein deposited at 180?C or more. These ages suggest a northern limit for the Pedras Grandes Suite, explaining the spatial relationship between the fluorite veins and the source rock. Tipo: Info:eu-repo/semantics/article Palavras-chave: SHRIMP; Pedras Grandes Suite; Zircon; Geochronology; Fluorite. Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652005000100010 Metamorphic evolution and U-Pb zircon SHRIMP geochronology of the Belizário ultramafic amphibolite, Encantadas Complex, southernmost Brazil Anais da ABC (AABC) Hartmann,Léo A.; Santos,João O.S.; Leite,Jayme A.D.; Porcher,Carla C.; Mcnaughton,Neal J.. The integrated investigation of metamorphism 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 Complex. Magmatic evidence of the magnesian basalt or pyroxenite protolith is only preserved in cores of zircon crystals, which are dated at 2257 ± 12 Ma. Amphibolite facies metamorphism M1 formed voluminous hornblende in the investigated rock possibly at 1989 ± 21 Ma. This ultramafic rock was re-metamorphosed at 702±21 Ma during a greenschist facies eventM2; the assemblage actinolite + oligoclase + microcline + epidote + titanite + monazite formed by alteration of hornblende. The metamorphic events are probably related... Tipo: Info:eu-repo/semantics/article Palavras-chave: Ultramafic amphibolite; Zircon geochronology; Encantadas Complex; Trans-Amazonian Cycle; Metamorphism. Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000300010 Registros recuperados: 4 Primeira ... 1 ... Última

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