Overview

Recent developments in high efficiency transport systems have transformed the capabilities of laser ablation - inductively coupled plasma - mass spectrometry (LA-ICP-MS).   Analyses can now be performed at around 50x higher speed than the previous generation technology, with high spatial resolutions down to the 1 µm level. The technology has also helped to double mass spectrometer efficiencies (as recently demonstrated by the supervisory team, see Craig et al., 2018), optimising measurement precisions and therefore resolution of compositional change. Developments to the core technology were originally driven by demands for higher throughput imaging in the biosciences (Van Malderen et al., 2016), thus are not yet in routine use for geoscientific applications. However, once fully characterised, the technology has the potential to be the gold standard for laser ablation ICP-MS in the earth sciences, enabling accurate measurement of lower elemental and isotopic concentrations, higher resolution interpretations of compositional change and representing a step change in capabilities for geoscientific applications.

The Chemistry Department at Loughborough University and the Geochronology and Tracers Facility at the British Geological Survey (BGS), have been heavily involved in the development and application of this technology (Douglas et al., 2015 and Managh et al., 2016). Now established as a capability, we wish to implement its wide application to the work of the geoscientific community. Areas of application will focus around U-series and U-Th-Pb geochronology (Horstwood et al., 2016) and elemental and isotope geochemistry, developing methods for their accurate quantification and mapping. Implementing these methods will also require changes in workflow, including improvements in analytical protocols, data handling techniques and the representation of data.

Figure 1. Elemental variation in a retina? Zoning in a garnet? Isotope ratio variation in a stalagmite? The scale and resolution of images for bioscience can be directly related to scales required for applications in geoscience. Here a 1µm laser spot was used to ablate fine structural features in rat retina, prior to ICP-MS analysis.

Methodology

Excimer laser ablation systems (193 nm) are available at both Loughborough and BGS where they will be coupled with a variety of ICP-MS instrumentation (single collector sector field (Loughborough), multiple collector, single collector sector-field and quadrupole (BGS)) using low-dispersion sample transport systems. A range of materials (e.g. carbonates, phosphates, silicates) and applications will be studied to optimise U-series and U-Th-Pb geochronology and elemental and isotope geochemistry using this set-up, mapping the materials down to 1µm spatial resolution and maintaining the best possible precision. The extent and effect of matrix effects on data accuracy will be considered, along with full uncertainty quantification. New data handling methods will be developed, providing the student with proficiency in statistical packages using R, Matlab and similar platforms.

 

Training and Skills

The student will be hosted in the Department of Chemistry, Loughborough University, but will spend considerable time at BGS (nearby at Keyworth). The Doctoral College at Loughborough University will provide training aligned with the Vitae Researcher Development Framework: knowledge and intellectual abilities, personal effectiveness, research governance and organisation, engagement, influence and impact. Relevant courses include statistical methodology, design of multifactor experiments, data management, intellectual property, presentation skills, academic writing and publication strategy. Full access to the BGS BUFI training programme will also be available to the student along with access to other facilities within BGS e.g. scanning electron microscopy.

Timeline

Year 1: CENTA training, Loughborough & BGS training courses, training in ICP-MS and laser ablation analysis at both Loughborough and BGS laboratories, introduction to geochronology and isotope geoscience, initial implementation of high speed sample transfer technologies at BGS and work on case study 1, in-house poster and oral presentations

Year 2: Development of high speed sample transfer technologies at BGS, development of data handling methods and visualisation platforms, completion and publication of case study 1, progression of case studies 2&3, attendance and presentation at national conferences

Year 3: Completion of data handling and visualisation protocols and platforms, completion of case studies 2-4, presentation at international conference, publication of one or more case studies, and commencement of write-up.

Partners and collaboration (including CASE)

This project is in collaboration with Dr. Matthew Horstwood from the British Geological Survey (BGS) at its main Keyworth site. Dr Horstwood has over 15 years’ experience in LA-ICP-MS U-Pb geochronology method development and application to geoscience, supervising postgraduate and postdoctoral students as part of a NERC Facility. The project will be supported by Elemental Scientific Lasers LLC, who have collaborated previously with Loughborough and will continue to provide software/instrumentation upgrades and engineer support. The student will be expected to maintain close contact with the company, which will include visits to their sites at Huntingdon, UK and Bozeman, USA.

Further Details

For information about this project, please contact Dr Amy Managh (A.J.Managh@lboro.ac.uk; http://www.lboro.ac.uk/departments/chemistry/staff/academic-research/amy-managh/) or Dr Matthew Horstwood (msah@bgs.ac.uk; https://www.bgs.ac.uk/staff/profiles/3745.html). For enquiries about the application process, please contact sci-pgr@lboro.ac.uk. Please quote CENTA18-LU9 when completing your online application form: http://www.lboro.ac.uk/study/apply/research/.