WiscSIMS


ACCESS GUIDE TO THE Wisc-SIMS LABORATORY The WiscSIMS ion microprobe facility is partly supported by a grant from the Instrumentation and Facilities Program, Division of Earth Sciences, National Science Foundation. Currently, the following stable isotope analyses are well-established and routinely available to external users. The beam sizes are typically 10µm and analyses take 3-10min/spot. Mineral analysis is limited by availability of standards. Potential users should inquire about creation of other standards. Oxygen isotopes (δ¹⁸O) with ~10µm spots: Zircon, quartz, olivine (Fo≥60), pyroxene, garnets, titanite, calcite, aragonite, dolomite, magnesite-siderite, plagioclase, K-feldspar, spinel, chromite: precision typically ~0.3‰ (2SD) Carbon isotopes (δ¹³C) with ~8µm spots: Diamond, graphite: precision typically ~0.4‰ (2SD) Calcite, aragonite, dolomite, magnesite-siderite,: precision typically ~0.7‰ (2SD) Sulfur isotopes (δ³⁴S) with ~10µm spots: Pyrite, pyrrhotite, chalcopyrite: precision typically ~0.4‰ (2SD) Si isotope (δ³⁰Si) with ~10µm spots: Quartz: precision typically ~0.2‰ (2SD) We request the users to obtain EPMA data of individual spots prior to SIMS analyses for correction of matrix effect. An analysis with smaller beam sizes down to 2µm (15-30min/spot) is available for some systems, but analysis is slower and with degraded precision (~1‰). Other applications with more difficult samples, requiring new standards, or with Li isotopes (δ⁷Li), Mg three isotopes (δ²⁵Mg and δ²⁶Mg), oxygen three isotopes (δ¹⁸O, δ¹⁷O, and Δ¹⁷O), and sulfur three isotopes (δ³⁴S, δ³³S, and Δ³³S) may also be available. Please contact us for more detailed information. APPLICATIONS FOR INSTRUMENT TIME* should be sent to WiscSIMS with a brief description of the project and samples. The WiscSIMS Oversight Board allocates instrument time according to the scientific merits and feasibility of the project. Applications should be made by grant PIs. FEE SCHEDULE: Since WiscSIMS receives a subsidy from NSF/EAR Instrumentation and Facilities Program, external NSF-funded investigators receive priority in allocation of instrument time and are eligible to perform analyses at a subsidized rate. The current subsidized rate is $1,440/day (12 hours), applied to US federally-funded research. The unsubsidized rate is $3,600/day (12 hours). PUBLICATION AND ACKNOWLEDGEMENT: We request that any data produced from WiscSIMS lab explicitly recognize NSF support in the acknowledgements of the journal articles with the following sentence: "WiscSIMS is partly supported by NSF (EAR03-19230, EAR07-44079)." WiscSIMS subscribes to the UCLA Protocol for collaborative research. “While all the personnel of the ion probe group take an active interest in assisting visitors, we have always sought flexible arrangements in defining our specific roles in the projects of external facility users. Specifically, this means that we have no requirement (explicit or implicit) that WiscSIMS scientists become actively involved in scientific interpretations, and certainly no expectation for co-authorship on routine data acquisition work. It has been our experience, however, that many visitors seek our expertise in the interpretative aspects of their work and many projects have tangibly benefited from collaborative efforts. We believe that it is not only useful, but necessary, that the facility be staffed by expert scientists who are not merely technologists but are also actively engaged in geochemical research.” CONTACT PERSONNEL: John Valley, Professor of Geology and Chair of the Oversight Board (email) Noriko Kita, Director of the Ion Microprobe Laboratory (email) © The Department of Geoscience, University of Wisconsin-Madison Page created: February 14, 2008; updated August 11, 2010. For comments and corrections please email.