Instrument upgrades and supporting equipment to establish a SIMS facility at Memorial university

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A Cameca IMS 4f ion microprobe Secondary Ion Mass Spectrometer (SIMS) will be upgraded and equipped to permit high precision in situ stable isotope and trace element analyses of nanogram samples of solid natural materials. The unique capabilities of the SIMS technique for the analysis of small objects, small volumes and small samples will be applied to a wide variety of studies in Earth and Environmental Science, including: i) Ore deposits genesis. A study of the giant Voisey's Bay deposit will examine episodicity of magmatic inputs, and determine whether sequential aliquots of assimilated S (and Se) are reflected as zonations within the ores. If this proves to be the case, then paired sulphur isotope and Se/S microanalysis will assist in delineation and extension of orebodies as mine development continues. Complementary ion imaging studies will also be applied to optimization of process metallurgy, and the environmental control of tailings and waste containments. ii) Volcanology. Microanalysis of sulphur isotopes in erupted materials will be applied to understanding the pre-eruptive accumulation of gaseous sulphur within convergent plate boundary volcanoes such as Nevado del Ruiz, Colombia. These volcanoes can release extremely large volumes of SO2 - with consequences for both volcanic explosivity hazard and recycling of S to the atmosphere, affecting climate and producing acid rain. iii) Marine Biomineralization/Paleoclimatology. SIMS analysis will be applied to the environmental monitoring of modern coral reefs. For example, in areas compromised by mine tailings, ion imaging can reveal the distribution of contaminant metals resident in entrained particles within the coral skeletons. This study will also use microanalyses of oxygen and carbon isotopes to detect short term changes in reef coral skeletons due to environmental stress such as severe storms or large fires. Fine scale determination of Sr/Ca ratios and oxygen isotopes in deep water coral species will be used to study the temperature record on the continental slope off Newfoundland and Labrador, as a monitor of the strength of the Labrador Current over time.