PHD Project

September 28, 2022

Developing a microfluorination technique for oxygen isotope analysis on biogenic silica


Human-induced climate change has altered environments around the world. In pursuit of environmental change resilience, we require vital palaeoclimate data and empirical context for contemporary and future climate change.  The oxygen isotope composition of biogenic silica is controlled by prevailing climate conditions and is routinely used to reconstruct past climate. However, the extraction and measurement of oxygen isotopes is a highly specialised technique, but requires large samples, hazardous reagents, and is time and energy inefficient. This restricts the resolution of isotope data available to answer important questions about past climates and environmental change.

The aim of this project is to:

  1. Undertake technical development for a microfluorination system, funded by NERC Strategic Capital, based on high-temperature pyrolysis and high precision isotope ratio mass spectrometry (IRMS). The system will provide substantially higher sample throughput at significantly reduced sample size compared to existing fluorination methods.
  2. Calibrate the system by direct comparison with step-wise fluorination.
  3. Test analytical capability for different types of biogenic silica that can be used to solve fundamental research questions across the UKRI-NERC science remit.
  4. Investigate the application of microfluorination to International Ocean Discovery Program (IODP) and International Continental Scientific Drilling Program (ICDP) core material.

The student will be based at the NERC National Environmental Isotope Facility, British Geological Survey, and will receive full training in IRMS and stable isotope geochemistry in collaboration with the University of Nottingham, as well as receive direct support and the opportunity to undertake a placement with CASE partner, Elementar UK; one of the world’s leading developers of high performance IRMS instrumentation. The student will be part of the BGS University Funding Initiative (BUFI) and will have the opportunity for overseas research visits and conference attendance. The project is in receipt of additional funding from the CASE partner and BUFI.

Applicants will require a minimum of a 2:1 degree that is relevant to the studentship and be able to show a strong background/interest in experimental work, problem solving, method/instrument development, mass spectrometry, isotope analysis, and/or stable isotope geochemistry. Please see the Envision DTP webpage for further information.

For enquiries please contact Dr Jack Lacey (