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(Reference retrieved automatically from SciELO through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

In situ Sr isotope analyses by LA-MC-ICP-MS of igneous apatite and plagioclase from magmatic rocks at the CPGeo-USP

Full text
Author(s):
Patricio Montecinos Munoz [1] ; Adriana Alves [2] ; Rogério Guitarrari Azzone [3] ; Pablo Cordenons [4] ; Sandra Morano [5] ; Walter Sproesser [6] ; Solange de Souza [7]
Total Authors: 7
Affiliation:
[1] Universidade de São Paulo. Institute of Geosciences - Brasil
[2] Universidade de São Paulo. Institute of Geosciences - Brasil
[3] Universidade de São Paulo. Institute of Geosciences - Brasil
[4] Universidad de Buenos Aires. Department of Geological Sciences - Argentina
[5] SENS Representações Comerciais - Brasil
[6] Universidade de São Paulo. Institute of Geosciences - Brasil
[7] Universidade de São Paulo. Institute of Geosciences - Brasil
Total Affiliations: 7
Document type: Journal article
Source: BRAZILIAN JOURNAL OF GEOLOGY; v. 46, p. 227-243, 2016-06-00.
Abstract

ABSTRACT: This contribution describes the successful implementation of in situ Sr isotope analyses by LA-MC-ICP-MS at the CPGeo-USP. The choice for an analytical configuration using measurements of half-masses allows the accurate assessment of lanthanide interferences, permitting the determination of Sr isotopes in important REE-rich accessory phases, such as apatite. Likewise, the on-peak-zero method effectively corrects the background contribution (both from Kr and residual Sr contributions from previous ablations) to the signals of the unknown samples. The analytical campaigns resulted in an accuracy, in respect to reference TIMS values, better than 57 ppm (~ ±0.000057 2σ SD) for a modern coral and the Batjberg clinopyroxene which impart significant quality to our data. Similarly, the majority of the stable Sr isotope ratios are close to the accepted values, which also confirms the effectiveness of the method. The achieved accuracy allows the identification and investigation of spatially-controlled isotopic heterogeneities on the micrometric scale in several Sr-rich minerals (apatite, carbonates, plagioclase, and clinopyroxene) with important implications to the understanding of relevant geochemical processes, particularly AFC, source geochemical heterogeneities and magma-mixing. (AU)

FAPESP's process: 10/20425-8 - Petrology of Meso-Cenozoic alkaline mafic magmatism of the southeastern part of the Brazilian Platform (SP): lamprophyre dikes and cumulitic stocks
Grantee:Rogério Guitarrari Azzone
Support Opportunities: Regular Research Grants
FAPESP's process: 11/07074-4 - Combination of quantitative textural analyses and in situ chemical-isotopic techniques in the study of felsic microgranular enclaves: implications to the evolution of magmatic chambers
Grantee:Adriana Alves
Support Opportunities: Regular Research Grants
FAPESP's process: 10/20380-4 - Development of the phosphate Lu-Hf geochronology at University of São Paulo: New apllication for high-precision Lu-Hf isotope micro-analysis in the oil and gas exploration
Grantee:Patricio Rodrigo Montecinos Muñoz
Support Opportunities: Scholarships in Brazil - Post-Doctoral