Improving environmental research through the isotope analysis of ever smaller archives

我们的目标是建立第一个英国的热电离质谱仪，配备新一代超灵敏探测器（以下简称microTIMS）。这种新一代质谱仪可以精确测量非气态元素的同位素组成（例如，Sr, Nd, Pb, Ca, Os），样品负载低得多（低至10皮克，相对于主流仪器，负载<1纳克的精度提高了8-10），动态范围不增加（提高了10倍，来自同位素的测试数据）。microTIMS将与现有的用于原位和同位素比率测定的仪器相结合，创建一个对卡迪夫大学整个NERC社区开放的同位素微量分析中心。虽然同位素地球化学在过去几十年里不断的技术创新取得了显著的突破，但一些关键的地质和环境档案仍未得到充分的研究，因为其中的关键同位素示踪剂无法足够精确地测量。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问题上开辟新的领域。我们将首先针对卡迪夫大学成功的nerc资助研究小组的研究范围内的问题：首先，我们将使用microTIMS开辟同位素岩石学领域，通过该领域，同位素测量可以在晶体尺度上进行，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头到喷口演化的复杂性，并有助于改进对地幔动力学、大陆地壳演化和地球构造机制、喷发前岩浆的储存和组合以及矿产资源形成的约束。其次，我们将把强大的钕和铅同位素示踪剂应用于小型有孔虫和自生样品，从而生成海洋环流、大陆风化和气候变化的成对百年尺度记录。此外，microTIMS将为有孔虫存在但缺乏的钕同位素分析开辟关键地点，如半深海粘土和深太平洋地点。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。三是提高对人为放射性核素和痕量金属污染在环境中的传播和迁移的认识。microTIMS的使用将使我们能够通过分析稀有放射性核素和铅同位素，并追踪从来源到被底栖生物吸收的直接联系，来揭示污染物的迁移、生物利用度和毒性。对资产的影响至关重要的是社区访问和产出的可用性。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，其任务是就科学优先事项提供建议，并确保广泛的社区使用该资产。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，该资产的学术用户将被要求在开放获取出版物中发布使用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.