A method for Se isotope analysis of low ng-level geological samples via double spike and hydride generation MC-ICP-MS

The isotopic signature of the chalcophile, redox-sensitive and moderately volatile element Se in geological materials may offer valuable new insights into the origin and evolution of volatiles in planetary systems. Here, we report a new method for Se isotope determination of low Se containing sample...

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Detalles Bibliográficos
Autores: Kurzawa, Timon, König. Stephan, Labidi, Jabrane, Yierpan, Aierken, Schoenberg, Ronny
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2017
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/414767
Acceso en línea:http://hdl.handle.net/10261/414767
https://doi.org/10.1016/j.chemgeo.2017.06.012
Access Level:acceso abierto
Palabra clave:Selenium isotopes
Heavy stable isotopes
Double spike hydride generation MC-ICP-MS
Mantle geochemistry
Descripción
Sumario:The isotopic signature of the chalcophile, redox-sensitive and moderately volatile element Se in geological materials may offer valuable new insights into the origin and evolution of volatiles in planetary systems. Here, we report a new method for Se isotope determination of low Se containing samples relevant to the Earth's mantle reservoir. We present a method that combines a double spike and hydride generation sample introduction system with a ThermoFisher Scientific® NeptunePlus™ MC-ICP-MS. The measurement routine takes advantage of methane injection in the instrument source during measurement, resulting in enhanced Se signals and suppression of polyatomic interferences. Purification of Se from natural samples was simplified by employing conventional ion exchange chromatography procedures. An external reproducibility of 0.15‰ (2σ) on δ82/76Se values for measurements performed on natural samples with Se abundances down to ~5 ng is obtained. We demonstrate that our technique allows the determination of Se isotope signatures of low Se-bearing geological materials with complex matrices such as mafic igneous rocks, which is essential to extend the Se isotopic investigation to Se-depleted planetary reservoirs such as the Earth's mantle.