U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration

Detalhes bibliográficos
Autor(a) principal: Chemale Jr, Farid
Data de Publicação: 2012
Outros Autores: Kawashita, Koji, Dussin, Ivo A., Ávila, Janaína N., Justino, Dayvisson, Bertotti, Anelise
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Repositório Institucional da UnB
Texto Completo: http://repositorio.unb.br/handle/10482/28257
https://dx.doi.org/10.1590/S0001-37652012005000032
Resumo: The LA-MC-ICP-MS method applied to U-Pb in situ dating is still rapidly evolving due to improvements in both lasers and ICP-MS. To test the validity and reproducibility of the method, 5 different zircon samples, including the standard Temora-2, ranging in age between 2.2 Ga and 246 Ma, were dated using both LA-MC-ICP-MS and SHRIMP. The selected zircons were dated by SHRIMP and, after gentle polishing, the laser spot was driven to the same site or on the same zircon phase with a 213 nm laser microprobe coupled to a multi-collector mixed system. The data were collected with a routine spot size of 25 μm and, in some cases, of 15 and 40 μm. A careful cross-calibration using a diluted U-Th-Pb solution to calculate the Faraday reading to counting rate conversion factors and the highly suitable GJ-1 standard zircon for external calibrations were of paramount importance for obtaining reliable results. All age results were concordant within the experimental errors. The assigned age errors using the LA-MC-ICP-MS technique were, in most cases, higher than those obtained by SHRIMP, but if we are not faced with a high resolution stratigraphy, the laser technique has certain advantages.
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spelling Chemale Jr, FaridKawashita, KojiDussin, Ivo A.Ávila, Janaína N.Justino, DayvissonBertotti, Anelise2017-12-07T04:58:00Z2017-12-07T04:58:00Z2012An. Acad. Bras. Ciênc.,v.84,n.2,p.275-296,2012http://repositorio.unb.br/handle/10482/28257https://dx.doi.org/10.1590/S0001-37652012005000032The LA-MC-ICP-MS method applied to U-Pb in situ dating is still rapidly evolving due to improvements in both lasers and ICP-MS. To test the validity and reproducibility of the method, 5 different zircon samples, including the standard Temora-2, ranging in age between 2.2 Ga and 246 Ma, were dated using both LA-MC-ICP-MS and SHRIMP. The selected zircons were dated by SHRIMP and, after gentle polishing, the laser spot was driven to the same site or on the same zircon phase with a 213 nm laser microprobe coupled to a multi-collector mixed system. The data were collected with a routine spot size of 25 μm and, in some cases, of 15 and 40 μm. A careful cross-calibration using a diluted U-Th-Pb solution to calculate the Faraday reading to counting rate conversion factors and the highly suitable GJ-1 standard zircon for external calibrations were of paramount importance for obtaining reliable results. All age results were concordant within the experimental errors. The assigned age errors using the LA-MC-ICP-MS technique were, in most cases, higher than those obtained by SHRIMP, but if we are not faced with a high resolution stratigraphy, the laser technique has certain advantages.O método LA-MC-ICP-MS utilizado para datação U-Pb in situ está cada vez mais preciso e reprodutível devido à melhor desempenho técnico das microssondas a LASER e os espectrômetro de massa com plasma acoplado indutivamente (ICP-MS). Com intuito de testar a validade e a reprodutibilidade deste método, 5 amostras diferentes foram selecionadas (incluindo o padrão Temora 2), com idades entre 2.2 Ga e 246 Ma, para serem analisadas por ambos os métodos LA-MC-ICPMS e SHRIMP. Os zircões selecionados foram primeiramente datados com SHRIMP e após foram polidos para que fossem realizadas, na maior parte dos casos, as datações com microssonda a LASER de 213 nm acoplada a um espectrômetro de massa com multicoletor misto (copo Faraday e MIC´s), no mesmo local ou fase do grão. Os dados foram obtidos pela ação do laser com tamanho de feixe igual a 25 μm, e mais raramente de 15 e 40 μm. A calibração cuidadosa entre o copo Faraday e MIC´s foi realizada com solução diluída de U-Th-Pb para calcular a taxa de conversão entre os coletores e o uso de um padrão de comportamento homogêneo e constante durante as análises, o padrão GJ-1, para a calibração externa foram decisivas para a obtenção de resultados confiáveis. Todas as idades obtidas foram concordantes dentro dos erros experimentais. Os erros obtidos pelo método LA-MC-ICP-MS foram, na maior parte, mais altos do que aqueles obtidos pelo método SHRIMP. A utilização do LA-MC-ICPMS pode ser vantajosa para obtenção de idades U-Pb in situ, desde que não seja necessária a definição estratigráfica de alta resolução.Em processamentoAcademia Brasileira de CiênciasU-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configurationinfo:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleMC-ICP-MSSHRIMPFaraday cupsMulti-ion Counting SystemU-Pb in situ zircon datingMC-ICP-MSSHRIMPCopos FaradaySistema de Contagem de Multiplicadores de ionsDatação in situ de U-Pb em zircãoinfo:eu-repo/semantics/openAccessengreponame:Repositório Institucional da UnBinstname:Universidade de Brasília (UnB)instacron:UNBORIGINALaop3312.pdfapplication/pdf49987924http://repositorio2.unb.br/jspui/bitstream/10482/28257/1/aop3312.pdf1570159f3ea4cc0f734267420b2c456aMD51open access10482/282572023-09-26 22:41:45.205open accessoai:repositorio2.unb.br:10482/28257Biblioteca Digital de Teses e DissertaçõesPUBhttps://repositorio.unb.br/oai/requestopendoar:2023-09-27T01:41:45Repositório Institucional da UnB - Universidade de Brasília (UnB)false
dc.title.pt_BR.fl_str_mv U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
title U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
spellingShingle U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
Chemale Jr, Farid
MC-ICP-MS
SHRIMP
Faraday cups
Multi-ion Counting System
U-Pb in situ zircon dating
MC-ICP-MS
SHRIMP
Copos Faraday
Sistema de Contagem de Multiplicadores de ions
Datação in situ de U-Pb em zircão
title_short U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
title_full U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
title_fullStr U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
title_full_unstemmed U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
title_sort U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
author Chemale Jr, Farid
author_facet Chemale Jr, Farid
Kawashita, Koji
Dussin, Ivo A.
Ávila, Janaína N.
Justino, Dayvisson
Bertotti, Anelise
author_role author
author2 Kawashita, Koji
Dussin, Ivo A.
Ávila, Janaína N.
Justino, Dayvisson
Bertotti, Anelise
author2_role author
author
author
author
author
dc.contributor.author.fl_str_mv Chemale Jr, Farid
Kawashita, Koji
Dussin, Ivo A.
Ávila, Janaína N.
Justino, Dayvisson
Bertotti, Anelise
dc.subject.keyword.pt_BR.fl_str_mv MC-ICP-MS
SHRIMP
Faraday cups
Multi-ion Counting System
U-Pb in situ zircon dating
MC-ICP-MS
SHRIMP
Copos Faraday
Sistema de Contagem de Multiplicadores de ions
Datação in situ de U-Pb em zircão
topic MC-ICP-MS
SHRIMP
Faraday cups
Multi-ion Counting System
U-Pb in situ zircon dating
MC-ICP-MS
SHRIMP
Copos Faraday
Sistema de Contagem de Multiplicadores de ions
Datação in situ de U-Pb em zircão
description The LA-MC-ICP-MS method applied to U-Pb in situ dating is still rapidly evolving due to improvements in both lasers and ICP-MS. To test the validity and reproducibility of the method, 5 different zircon samples, including the standard Temora-2, ranging in age between 2.2 Ga and 246 Ma, were dated using both LA-MC-ICP-MS and SHRIMP. The selected zircons were dated by SHRIMP and, after gentle polishing, the laser spot was driven to the same site or on the same zircon phase with a 213 nm laser microprobe coupled to a multi-collector mixed system. The data were collected with a routine spot size of 25 μm and, in some cases, of 15 and 40 μm. A careful cross-calibration using a diluted U-Th-Pb solution to calculate the Faraday reading to counting rate conversion factors and the highly suitable GJ-1 standard zircon for external calibrations were of paramount importance for obtaining reliable results. All age results were concordant within the experimental errors. The assigned age errors using the LA-MC-ICP-MS technique were, in most cases, higher than those obtained by SHRIMP, but if we are not faced with a high resolution stratigraphy, the laser technique has certain advantages.
publishDate 2012
dc.date.issued.fl_str_mv 2012
dc.date.accessioned.fl_str_mv 2017-12-07T04:58:00Z
dc.date.available.fl_str_mv 2017-12-07T04:58:00Z
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
format article
status_str publishedVersion
dc.identifier.citation.fl_str_mv An. Acad. Bras. Ciênc.,v.84,n.2,p.275-296,2012
dc.identifier.uri.fl_str_mv http://repositorio.unb.br/handle/10482/28257
dc.identifier.doi.pt_BR.fl_str_mv https://dx.doi.org/10.1590/S0001-37652012005000032
identifier_str_mv An. Acad. Bras. Ciênc.,v.84,n.2,p.275-296,2012
url http://repositorio.unb.br/handle/10482/28257
https://dx.doi.org/10.1590/S0001-37652012005000032
dc.language.iso.fl_str_mv eng
language eng
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
eu_rights_str_mv openAccess
dc.publisher.none.fl_str_mv Academia Brasileira de Ciências
publisher.none.fl_str_mv Academia Brasileira de Ciências
dc.source.none.fl_str_mv reponame:Repositório Institucional da UnB
instname:Universidade de Brasília (UnB)
instacron:UNB
instname_str Universidade de Brasília (UnB)
instacron_str UNB
institution UNB
reponame_str Repositório Institucional da UnB
collection Repositório Institucional da UnB
bitstream.url.fl_str_mv http://repositorio2.unb.br/jspui/bitstream/10482/28257/1/aop3312.pdf
bitstream.checksum.fl_str_mv 1570159f3ea4cc0f734267420b2c456a
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repository.name.fl_str_mv Repositório Institucional da UnB - Universidade de Brasília (UnB)
repository.mail.fl_str_mv
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