Improving environmental research through the isotope analysis of ever smaller archives

我们的目标是建立第一台配备新一代超灵敏探测器（以下简称microTIMS）的英国热电离质谱仪。这种新一代质谱仪允许精确测量非气态元素的同位素组成（例如，Sr，Nd，Pb，Ca，Os），样品加载量大大降低（低至10皮克，与主流仪器相比，在加载量<1纳克时精度提高8-10倍），动态范围增大（提高10倍，测试数据来自IsotopX）。microTIMS将与现有的原位和同位素比值测定专用仪器相结合，在卡迪夫大学建立一个向整个NERC社区开放的同位素微量分析中心。尽管过去几十年来同位素地球化学领域的不断技术创新取得了显著突破，一些重要的地质和环境档案仍然没有得到充分的研究，因为其中的关键同位素示踪剂无法测量足够精确。我们的目标是利用microTIMS前所未有的能力，在地球和环境科学的几个长期存在的问题上开辟新的天地。我们将首先针对卡迪夫大学成功的NERC资助的研究小组的职权范围内的问题：首先，我们将使用microTIMS开辟同位素岩石学领域，通过该同位素测量在晶体尺度上进行，并直接置于岩石学观察的背景下。这种方法将有助于解开岩浆从源到喷口演化的复杂性，并有助于改善对地幔动力学、大陆地壳和地球构造体制的演化、岩浆在喷发前的储存和聚集以及矿产资源形成的限制。从而能够产生成对的百年尺度的海洋环流、大陆风化和气候变化记录。此外，microTIMS将打开关键站点的Nd同位素分析有孔虫存在，但稀缺，如半远洋粘土和深太平洋网站。这些档案包含了大量目前无法阅读的信息，涉及海洋气候系统在一系列时间尺度上运行的许多过程和临界点。第三，我们将提高对环境中人为放射性核素和微量金属污染的扩散和流动性的认识。微型TIMS的使用将使我们能够分析稀有放射性核素和铅同位素，并追踪从源头到底栖生物吸收的直接联系，从而揭示污染物的迁移、生物可利用性和毒性。microTIMS的使用和维护将由卡迪夫的技术和学术人员提供支持。我们将建立一个由外部用户组成的科学咨询小组，其使命将是就科学优先事项提出建议，并确保广泛的社区获得资产。早期职业研究人员将优先获得该资产，以确保在最新一代英国地球化学家中传播尖端分析方法。此外，将要求该资产的学术用户在开放获取的出版物中发布使用microTIMS生成的数据集，并将其存档在国家地球科学数据中心。

We aim to set up the first UK-based Thermal Ionisation Mass Spectrometer equipped with a new generation of ultra-sensitive detectors (hereafter referred to as microTIMS). This new generation of mass spectrometers allows precise measurement of the isotope composition of non-gaseous elements (e.g., Sr, Nd, Pb, Ca, Os) with much lowered sample loads (down to 10 picograms, with 8-10 increase in precision at loads <1nanogram relative to mainstream instruments) and uncreased dynamic range (10 times improvement, test data from IsotopX). The microTIMS will be combined with existing instrumentation dedicated to in situ and isotope ratio determination to create a centre for isotope microanalysis open to the entire NERC community at Cardiff University.While constant technological innovations in isotope geochemistry over the last decades have allowed notable breakthroughs, several critical geological and environmental archives remain vastly understudied because key isotope tracers within them cannot be measured precisely enough. Our ambition is to use the unprecedented capabilities of the microTIMS to break new grounds on several longstanding problems in Earth and Environmental Sciences. We will first target questions within the remit of successful NERC-funded research groups at Cardiff University:First, we will use the microTIMS to open up the field of isotope petrology, by which isotope measurements are made on the crystal scale and directly put in the context of petrological observations. Such an approach will allow disentangling the complexities of magma evolution from source to vent and allow improved constraints on mantle dynamics, the evolution of continental crust and tectonic regime on Earth, the storage and assembly of magma before eruption and the formation of mineral resources.Second, we will apply the powerful neodymium and lead isotope tracers to small foraminiferal and authigenic samples, enabling the generation of paired centennial-scale records of ocean circulation, continental weathering and climate variability. Furthermore, microTIMS will open up critical sites for Nd isotopic analysis where foraminifera are present but scarce, such as hemipelagic clays and deep Pacific sites. These archives contain a wealth of currently unreadable information about many processes and tipping points in the ocean-climate system operating on a range of timescales. Third, we will improve our understanding of the spread and mobility of anthropogenic radionuclides and trace-metal pollution in the environment. Use of the microTIMS will allow us to unravel pollutant migration, bioavailability and toxicity by allowing the analysis of rare radionuclides and Pb isotopes and tracing the direct link from source to uptake into benthic organisms.Critical to the impact of the asset is community access and availability of outputs. Usage and maintenance of microTIMS will be supported by the technical and academic staff at Cardiff. We will create a scientific advisory panel composed of external users whose mission will be to advise on the scientific priorities and ensure broad community access to the asset. Early career researchers will be given priority access to the asset to ensure spreading of cutting-edge analytical methods amongst the newest generation of UK geochemists. Furthermore, academic users of the asset will be requested to publish datasets generated using microTIMS in open-access publications and archive them at the National Geoscience Data Centre.