Abstract
The whole-rock trace-element compositions of igneous rocks provide primary geochemical information about their petrogenesis. Such compositions can be determined by LA–ICP–MS analysis of fused-glass samples as well as the conventional solution ICP–MS method. However, in contrast to basalt and andesite, the fused-glass method is not suitable for Si-rich rocks (granite and rhyolite) due to the difficulty of making homogeneous glasses. To extend the method to Si-rich rocks, we adopted an MgO dilution process to prepare fused glasses and evaluated the technique by analysis of granite and rhyolite reference materials. Dilution of 30 mg of powdered samples with 10 mg MgO facilitated the preparation of homogeneous fused-glass samples of felsic rocks. LA–ICP–MS analyses indicate that the fused glass is homogeneous in the contents of most incompatible elements considered in igneous petrology. The glass enables the analysis of these elements in felsic rocks within 20% deviation from reference data. The sample data are consistent with reference values for rhyolite although Zr and Hf data deviate significantly (by ~40%) from reference values for granitic rocks.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.