Improving environmental research through the isotope analysis of ever smaller archives

Lead Research Organisation: CARDIFF UNIVERSITY
Department Name: Sch of Earth and Environmental Sciences


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.


10 25 50