BGS blogs

My role as a stable isotope research assistant

Charlotte Hipkiss has recently taken up a new position in the National Environmental Isotope Facility at BGS and gives us a little insight into her new position.

19/12/2023

Charlotte Hipkiss working in the National Environmental Isotope Facility (NEIF). BGS © UKRI.

In July, I started my role as a stable isotope research assistant at the National Environmental Isotope Facility (NEIF) at BGS’s headquarters in Keyworth, Nottinghamshire.

Before I took on this role, I was studying for my PhD in ocean and earth science at the University of Southampton. My project involved the use of stable isotopes as part of a multi-proxy study to reconstruct climatic and environmental changes in tropical South Pacific islands during the late Holocene. The aim was to try and identify periods of drought and whether they were related to the timing of human migration across the tropical Pacific.

During the course of my PhD studies, I took part in a placement scheme that enabled me to gain experience working in the stable isotope facilities at BGS, learning preparation protocols and getting some hands-on experience with mass spectrometry. This enabled me to have a smooth transition into my new role as a stable isotope research assistant.

My new role so far has primarily involved analysing organic samples for the stable isotopes of carbon and nitrogen with Dr Jack Lacey. We work with a range of samples including lake sediments, ocean sediments and plants. The sample preparation involves using acid to remove any inorganic carbon from the sediment; the acid is then washed-out using water and the samples are dried. Following this, they are ground and weighed into small tin capsules ready for analysis. The data these analyses produce will provide scientists with information such as changing environmental conditions through time, including changes to vegetation, productivity and human effects on environmental systems.

These samples are analysed using our Isoprime PrecisION with Elementar vario ISOTOPE cube, which calculates the percentage carbon (C) and nitrogen (N) content, as well as the stable isotope values for δ¹⁵N and δ¹³C. This system works by combusting the samples at 950°C so they transform into gas. The gas is then passed through a series of traps that remove any unwanted contaminants or water and reduce the gas down to the elements we want to measure. The gas is then passed through to the mass spectrometer, where it is measured against a monitoring gas. This has let me experience independently running the organics mass spectrometer, giving me the chance to learn more about the system, and offers regular problem-solving opportunities.

I have also had time to learn the process for running the small carbonates mass spectrometer with our geochemistry technician, Kotryna Savickaite. This has involved working with very different materials such as corals, shells and other marine organisms. It has been good to get involved with other aspects of the varied work we do at NEIF and expand on my skills and knowledge in this area.

Everyone in the stable isotope team has been friendly and welcoming and I am keen to continue learning more about the work that goes on at BGS and get involved with some cool science.