Magnesium isotope analysis of olivine and pyroxene by SIMS: Evaluation of matrix effects.

ABSTRACT: The performance of multi-collector secondary ion mass spectrometry (MC-SIMS) for Mg isotope ratio analysis was evaluated using 17 olivine and 5 pyroxene reference materials (RMs). The Mg isotope composition of these RMs was accurately and precisely determined by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS), and these measured isotope ratios were used to evaluate SIMS instrumental mass bias as a function of the forsterite (Fo) content of olivine. The magnitude of the Mg isotope matrix effects were ~3‰ in δ²⁵Mg, and are a complex function of olivine Fo content, that ranged from Fo_59.3 to Fo₁₀₀. In addition to these Mg isotope matrix effects, Si⁺ ion yields and Mg⁺/Si⁺ ion ratios varied as a complex

SUBMITTER: Fukuda K 

PROVIDER: S-EPMC8637499 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature