%0 Journal Article
%T U-Pb zircon in situ dating with LA-MC-ICP-MS using a mixed detector configuration
%A Chemale Jr
%A Farid
%A Kawashita
%A Koji
%A Dussin
%A Ivo A.
%A ¨¢vila
%A Jana¨ªna N.
%A Justino
%A Dayvisson
%A Bertotti
%A Anelise
%J Anais da Academia Brasileira de Ci¨ºncias
%D 2012
%I Academia Brasileira de Ci¨ºncias
%R 10.1590/S0001-37652012005000032
%X 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 ¦̀m and, in some cases, of 15 and 40 ¦̀m. 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.
%K mc-icp-ms
%K shrimp
%K faraday cups
%K multi-ion counting system
%K u-pb in situ zircon dating.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S0001-37652012000200005&lng=en&nrm=iso&tlng=en