Micro-FTIR analysis system

虽然研究人员普遍认为，斑岩和浅成热液矿床中的金属和硫的来源是长英质岩浆，金属运输的介质是岩浆源的含水流体，但这种流体在岩浆中的浓度、其组成（包括运输金属的挥发性物质的浓度）、其性质（液体或蒸汽）以及其析出的时间却知之甚少。在岩浆结晶过程中被困在矿物深处的硅酸盐玻璃包裹体，为回答这些问题提供了理想的信息来源。从火山学的角度来看，这些包裹体还提供了有关溶出挥发性物质（H2O, CO2, SO2）的性质和组成的重要信息，这些挥发性物质控制着岩浆上升的速度以及喷发的方式和强度。然而，为了能够正确地解释对这些挥发物析出的控制，更具体地说，它们在硅酸盐熔体和含水流体之间的分配，需要在已知压力和温度条件下对已知成分的岩浆进行实验。麦吉尔大学（McGill University）和西蒙弗雷泽大学（Simon Fraser University）正在进行旨在解决这些问题的研究，这在很大程度上依赖于分析硅酸盐玻璃挥发性成分的能力。从历史上看，获得此类数据的首选方法是二次离子质谱法（SIMS）。然而，最近微傅立叶变换红外光谱技术的发展使后者成为一种非常有吸引力、廉价和优越的获取此类数据的手段。该提案是申请人和共同申请人的联合倡议，他们在几个项目中合作，需要硅酸盐玻璃挥发性分析的能力。该申请要求获得资金，以获得用于此目的的微型ftir光谱仪和红外显微镜，这些仪器将安置在麦吉尔大学。该设备将用于支持申请人和共同申请人以及13名研究生和2名博士后的研究。

Although researchers are generally agreed that the source of the metals and sulphur in porphyry and epithermal mineral deposits is a felsic magma, and that the medium of metal transport is an aqueous fluid of magmatic origin, the concentration of this fluid in the magma, its composition, including the concentration of volatile species that transport metals, its nature (liquid or vapour) and the timing of its exsolution are poorly known. Silicate glass inclusions, which are trapped at depth in minerals forming during the crystallization of the magma, provide an ideal source of information for answering these questions. From the perspective of volcanology, such inclusions also provide essential information on the nature and composition of the exsolving volatile species (H2O, CO2, SO2) that control the rate of magma ascent and the style and intensity of eruptions. In order, however, to be able to properly interpret the controls on the exsolution of these volatiles, and more specifically, their partitioning between the silicate melt and the aqueous fluid, experiments are required at known pressure and temperature conditions for magmas of known composition. Research designed to address these issues is being conducted at McGill University and Simon Fraser University and depends heavily on the ability to be able to analyse the volatile composition of silicate glass. Historically, the preferred means of obtaining such data was secondary ion mass spectrometry (SIMS). However, recent developments in micro-FTIR (Fourier-Transform Infrared) spectroscopy make the latter a very attractive, inexpensive and superior means of obtaining such data. This proposal is a joint initiative of the applicant and co-applicants, who are collaborating in several projects requiring a capability for volatile analysis of silicate glasses. The application requests funds to obtain a micro-FTIR spectrometer and infrared microscope for this purpose, which will be housed at McGill University. The equipment will be used to support the research of the applicant and co-applicants and that of 13 graduate students and two post-doctoral fellows.