Community Facility Support: The UCLA National Ion Microprobe

观测科学，如天文学和地质学，直接受到我们用来观察的工具的清晰度的限制，无论它是望远镜还是质谱仪。对于我们可以看到的距离、我们可以看到的精确程度或我们可以看到的规模有多小的每一个数量级的增长，基本的发现都在等待着我们。20世纪60年代，随着现代质谱仪的出现，我们对地球及其在太阳系中的位置的理解发生了革命性的变化，现在可以高度精确地测量元素的同位素比率。这些分析使我们能够确定太阳系的年龄，并确定山脉何时上升或沉积盆地何时达到适合形成石油的温度条件。早期这种测量是在大块岩石样本上进行的，但随着方法的出现，可以对微小的(大约你头上一根头发的宽度)斑点进行分析，我们发现了一个丰富的信息世界，当我们只看大块样本时，我们无法获得这些信息。离子探针出现于20世纪80年代，是地质材料原位微尺度同位素分析的终极工具。然而，这些仪器庞大、复杂、昂贵--如此昂贵，以至于即使是像我们这样庞大和富有的国家，也只能负担得起少数几个地球科学的研究。自1993年加州大学洛杉矶分校接收了北半球的第一个离子微探测器以来，我们运营了一个国家设施，为更广泛的地球科学家社区提供这一专门仪器的接入。300多名外部调查人员，包括许多学生和博士后，已经访问了该设施。与此同时，我们继续肩负起责任，通过研究广泛的重要问题，在社会上展示科学领导力。加州大学洛杉矶分校国家离子微探测器设施产生的数据，如480多篇科学文章所记录的那样，导致了一系列重大发现，如太阳的同位素组成和地球上已知的最古老的水和生命证据的年龄。这笔赠款提供的资金1)确保国家的地球化学家、宇宙化学家和地质年代学家继续使用我们近乎独特的设施，2)为加州大学洛杉矶分校的科学家提供必要的资源，以继续开发和完善现有的和新的研究方法，用于地球化学、地球生物学、宇宙化学和地质年代学的研究。科研训练是设施工作的一个重要方面。2010至2016年间，共发表论文81篇(博士44篇，硕士34篇，学士3篇)根据加州大学洛杉矶分校的离子微探针数据完成了这项研究，另有13篇论文正在进行中。在这笔支助赠款的背景下，我们举办了一次年度讲习班，将全国各地的学生带到加州大学洛杉矶分校，为期一周，学习离子微探测器在地球科学中的应用，并接触离子微探测器和相关设备和技术。超过150名学生参加了这些工作坊。中心科学家继续参与当地和全国的协同活动，包括专业活动和K-12教育和外展。这项提议要求继续支持加州大学洛杉矶分校的离子微探测器实验室作为国家地球科学研究设施。除了使外部调查人员能够进入该设施外，还寻求资金进一步开发分析方法，利用二次离子质谱仪的独特优势，对与地球化学和地质年代学问题有关的同位素丰度进行现场分析。随着新的Cameca IMS1290及其高亮度Hyperion-2离子源的投入使用，我们建议针对我们实验室开展的主要应用对我们的两台仪器进行优化-IMS1270成为专用的U-Pb多采集仪，IMS1290专注于高精度的稳定同位素比率测量。具体地说，我们建议开展：1)SIMS多收集器Lu-Hf同位素分析；2)石英中钛、锆石和金红石温度压力计的交叉校准；3)耳石稳定同位素变化作为鱼类栖息地和生命周期的监测；4)硫同位素作为地球和火星上的地球化学示踪；5)锆石中的C和S作为岩浆挥发监测。

Observational sciences, such as astronomy and geology, are directly limited by the clarity of the tools we use for observing, whether it be a telescope or a mass spectrometer. For every order of magnitude increase in how far we can see, how precisely we can see, or in how small a scale at which we can see, fundamental discoveries await. Our understanding of the Earth and its place in the solar system was revolutionized in the 1960s by the advent of the modern mass spectrometer, which now permits highly accurate measurement of isotope ratios of elements. These analyses permit us to date the age of the solar system and determine when a mountain range rose or when a sedimentary basin reached temperature conditions suitable for forming petroleum. Early such measurements were performed on bulk rock samples, but as methods emerged that permit analysis on tiny (about the width of one of the hairs on your head) spots, we discovered a rich world of information that had eluded us when we looked only at bulk samples. The ion microprobe emerged in the 1980s as the ultimate tool for in situ microscale isotopic analyses of geologic materials. However, these instruments are large, complex, and expensive - so expensive that even a nation as large and rich as ours can only afford to support a handful in the Earth sciences. Since 1993, when UCLA took delivery of the first ion microprobe in the northern hemisphere, we have operated a national facility that provides access of this specialized instrumentation to the broader community of Earth scientists. Over 300 external investigators, including numerous students and postdocs, have accessed the facility. At the same time, we bear a continuing responsibility to demonstrate scientific leadership within the community by pursuing a broad range of important questions. Data produced from the UCLA national ion microprobe facility, as documented in over 480 scientific articles, has led to an array of significant discoveries such as the isotopic composition of the Sun and the age of the oldest known evidence for water and life on Earth. Funds provided in this grant 1) ensure that the nation's geochemists, cosmochemists, and geochronologists continue to have access to our near-unique facilities, and 2) provide UCLA scientists the resources required to continue to develop and refine existing and new methods for research in geochemistry, geobiology, cosmochemistry, and geochronology. Research training is an important aspect of the facility work. Between 2010 and 2016, 81 theses (44 Ph.D., 34 M.S., and 3 B.S.) that relied on UCLA ion microprobe data were completed with another 13 theses ongoing. In context of this support grant, we conduct an annual workshop that bring students from across the country to UCLA for one week to learn about applications of the ion microprobe to the geosciences and to acquire exposure to the ion microprobe and related equipment and techniques. Over 150 students have participated in these workshops. Center scientists continue to be involved in synergistic activities both locally and nationally, including professional activities and K-12 education and outreach.This proposal requests continued support of the UCLA ion microprobe laboratory as a national facility for research in the geosciences. In addition to enabling access to the facility by external investigators, funds are sought to further develop analytical methods that take advantage of the unique strengths of secondary ion mass spectrometry for in situ analyses of isotopic abundances relevant to problems in geochemistry and geochronology. With the commissioning of the new CAMECA ims1290 and its high brightness Hyperion-2 ion source, we propose to optimize each of our two instruments for the principal applications undertaken in our laboratory - the ims1270 to become a dedicated U-Pb multi-collection instrument and the ims1290 to focus on high precision stable isotope ratio measurements. Specifically, we propose to develop: 1) SIMS multi-collector Lu-Hf isotopic analysis, 2) cross-calibration of Ti-in-quartz, Ti-in-zircon, and Zr-in-rutile thermobarometers, 3) correlated stable isotope variations in otoliths as monitors of fish habitat and lifecycles, 4) sulfur isotopes as geochemical tracers on Earth and Mars, and 5) C and S in zircon as magma volatile monitors.