Multi-element analysis of melt and fluid inclusions with improved detection capabilities for Ca and Fe using laser ablation with a dynamic reaction cell ICP-MS

Analysis of melt and fluid inclusions by laser ablation inductively coupled plasma mass spectrometry has contributed significantly to our understandin g of magmatic and hydrothermal processes. The combination of laser ablation and ICP-MS detection allows the quantification of it wide variety or eleme nts in inclusions its small as 10 mum. The transient nature of the signal a nd the low amount of sample material have maintained quadrupole based ICP-M S as the instrumentation of choice. due to high sensitivities combined with fast sequential detection capabilities. However, the detection of some ele ments was limited due to polyatomic and isobaric interferences. Recently in troduced dynamic reaction cell technology offers the reduction of interfere nces commonly found in ICP-MS and thus the determination of important eleme nts with improved signal to noise ratio. The capability of a dynamic reacti on cell for multi-element analysis with short transient signals was studied for the simultaneous determination of major, minor and trace element conce ntrations in single fluid and melt inclusions. Analyses performed with the dynamic reaction cell were compared with results obtained ill the standard mode operation of the ICP-MS. The results show that the reaction cell is we ll Suited for fast transient multi-element analysis, providing very compara ble results to the standard mode. Hydrogen has been found efficient for rem oving Ar+ and Ar-based polyatomic ions from the mass spectrum when a buffer gas is added to enhance thermalization of the ions. Due to this, the limit s of detection for Ca were improved by 2.5 orders of magnitude and a factor of 20 for Fe using the most abundant isotopes for analysis.