Facility Support: For The Northeast National Ion Microprobe Facility (NENIMF)

Woods Hole Oceanographic Institution, Woods Hole MA

Investigators

Abstract

This grant supports the continued operation of the Northeast National Ion Microprobe Facility (NENIMF) as a National Secondary Ion Mass Spectrometry (SIMS) Facility serving the geoscience community. The principal strengths of SIMS relative to other micro-analytical techniques are its high spatial resolution and the capability for high-precision measurements of both concentration and isotopic composition of light elements such as hydrogen, lithium, boron, carbon, nitrogen, and oxygen. The analytical capabilities and expertise of the NENIMF are focused in two areas: determination of magmatic volatiles in silicate glasses and analysis of biogenic carbonates as records of climate change and its impacts on marine organisms, making the NENIMF a unique interdisciplinary resource to the geosciences community, with minimal overlap to the other National SIMS Facilities. Since January 2011, the NENIMF has accommodated 93 users from 47 different institutions, including 14 users from institutions outside the United States. Over the past 22 years, a total of 328 peer reviewed scientific papers have been published using data collected at the NENIMF for an average of 15 publications per year. The NENIMF is equipped with two Cameca SIMS instruments: an IMS 1280 and an IMS 3f. The IMS 1280 is a double focusing mass spectrometer with a large radius magnetic sector (585 mm), and ion optics optimized to attain a mass resolving power (MRP= M/delta M) of 6,000 without significant loss of secondary ion intensity. The IMS 3f is a double focusing mass spectrometer with a small radius magnetic sector that has been used for a wide spectrum of geochemical studies since 1978 and has been upgraded to Linux-based computer control of many components via Labview-based software (LabSIMS). The combination of these 2 instruments and the technical and scientific expertise of the NENIMF provides the geoscience community with a unique resource. Publications related to magmatic volatiles comprised 69% of the NENIMF total over the past 5 years, while 13% were focused on biogenic carbonates. In addition to these areas of specialization, NENIMF users have taken advantage of the Cameca IMS 1280 to work on a range of topics that include B isotopes in MORB glasses and subduction zone minerals, Zr in rutile geospeedometry, Ti diffusion in quartz, and U-Th-Pb dating of monazite and zircon. New analytical protocols developed at the NENIMF over the past few years include high-precision analysis of the isotopic composition of boron in low concentration basaltic glasses, and determination of D/H in the accessory mineral apatite. Support for the NENIMF meets the NSF Broader Impacts criteria in several different ways. Discovery and understanding are advanced while promoting teaching, training, and learning and participation of underrepresented groups is broadened through the involvement of undergraduates, graduate students, and postdocs. WHOI Undergraduate Summer Student Fellows, Postdoctoral Scholars, and WHOI/MIT Joint Program graduate students are specifically targeted for involvement in research projects with NENIMF personnel and WHOI faculty in which they are intimately involved with SIMS techniques. Involvement of young scientists in SIMS-based research is encouraged through annual short-courses. Infrastructure for research and education are enhanced through making both our existing analytical platforms, and those to be developed by the NENIMF personnel during the funding period, available to scientists and students from diverse disciplines. Research results are disseminated broadly to enhance scientific and technological understanding through an average of 15 publications per year that result from use of the facility. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.