Acquisition of a multi-collector, inductively coupled plasma mass spectrometer (MC-ICP-MS)

将在威斯康星州-麦迪逊大学的放射性同位素实验室安装一台电感耦合等离子体质谱仪。 新的MC-ICP-MS将取代1999年安装的现有仪器，并将与最近安装的飞秒激光消融系统相结合。 新仪器将用于同位素地球化学三个领域的研究：金属稳定同位素、铀系地质年代学和长寿命同位素地质年代学及放射性成因示踪剂。 稳定金属同位素的工作将包括涉及Mg、Si和Fe的研究，主要精力放在同位素分馏因子的实验测定上。 此外，一项重要的工作将涉及太古代和元古代带状铁地层、黑色页岩和碳酸盐岩的原位同位素分析。 铀系地质年代学的研究将致力于了解100 kyr火山系统的演化，其中将238 U-230 Th年龄与40 Ar/39 Ar年龄以及广泛的地球化学数据（包括Sr、Nd、Pb和Hf同位素）进行比较。 一项关于破火山口复合体的新倡议将与早先关于中央喷口/复合火山的工作进行比较。 关于长寿命地质年代学系统和同位素示踪剂（包括U-Th-Pb、Lu-Hf和Rb-Sr）的工作将包括通过飞秒激光烧蚀进行的原位U-Pb/Lu-Hf锆石研究，以及对相同材料的O和Li同位素研究;项目将包括Hadean锆石以及白垩纪锆石，这是更广泛的时间尺度计划的一部分。 此外，还将采用飞秒激光烧蚀法对长石进行现场Sr和Pb同位素分析，用于物源研究和火山演化研究;对于前者，Sr和Pb分析将与单颗粒40 Ar/39 Ar分析相结合。 新的仪器将由学生和博士后在威斯康星大学麦迪逊分校使用，也将接待来自中西部和其他地区的访问科学家。

An Inductively Coupled Plasma Mass Spectrometer (MC-ICP-MS) will be installed in the Radiogenic Isotope Laboratory at the University of Wisconsin - Madison. The new MC-ICP-MS will replace an existing instrument that was installed in 1999, and will be coupled to a recently installed femtosecond laser ablation system. The new instrumentation will be used for research in three areas of isotope geochemistry: metal stable isotopes, U-series geochronology, and long-lived isotope geochronology and radiogenic tracers. Work in stable metal isotopes will include studies involving Mg, Si, and Fe, with a major effort expended on experimental determination of isotope fractionation factors. In addition, a significant effort will involve in situ isotopic analysis of Archean and Proterozoic banded iron formations, black shales, and carbonates. Research in U-series geochronology will be directed towards understanding the evolution of 100 kyr volcanic systems, where 238U-230Th ages are compared with 40Ar/39Ar ages, as well as extensive geochemical data, including Sr, Nd, Pb, and Hf isotopes. A new initiative on caldera complexes will provide comparisons with earlier work on central vent/composite volcanoes. Work on long-lived geochronological systems and isotope tracers, including U-Th-Pb, Lu-Hf, and Rb-Sr, will include in situ U-Pb/Lu-Hf zircon studies by femtosecond laser ablation, coupled with O and Li isotope studies of the same materials; projects will include Hadean zircons, as well as Cretaceous zircons that are part of a broader timescale initiative. In addition, in situ Sr and Pb isotope analyses of feldspars by femtosecond laser ablation will be pursued, both for provenance studies, as well as volcanic evolution studies; for the former, Sr and Pb analysis will be coupled to single-grain 40Ar/39Ar analysis. The new instrumentation will be used by students and post-docs at UW-Madison, and will also host visiting scientists from the Midwest and other areas.