Tim Elliott

This PhD project at the University of Bristol's School of Earth Sciences focuses on benchmarking the major element isotopic compositions of chondritic meteorites, which are crucial for understanding the compositional evolution of the proto solar nebula and planetary formation processes. Chondritic meteorites serve as a reference for the bulk composition of the solar system, and comparing their isotopic signatures with those of planetary bodies can reveal key insights into the mechanisms of planet growth, such as volatile loss during accretion. The research aims to construct a robust new dataset for the isotopic composition of four major planetary-forming elements: silicon (Si), magnesium (Mg), calcium (Ca), and nickel (Ni). The project leverages innovative measurement methodologies developed by the Bristol Isotope Group, including advanced mass spectrometry techniques (MC-ICPMS) and novel double spiking methods tailored for three-isotope systems. Initial work will focus on Ni isotopes using conventional double spiking, followed by Si and Mg using critical mixture double spiking, and finally Ca, which requires specialized collision cell MC-ICPMS due to isobaric interferences. Sample preparation and characterization are integral to the project, involving petrographic analysis and microbeam techniques to ensure representative sampling and accurate documentation of meteorite petrology. The project will also address the effects of fluid alteration in carbonaceous chondrites, contextualizing Mg and Ni isotopic variations through sequential analyses informed by oxygen isotope measurements. The successful candidate will join the Bristol Isotope Group and receive comprehensive training in laboratory techniques, mass spectrometry, and microbeam analysis. Collaboration with cosmochemists and participation in national and international conferences are expected, with opportunities to publish research findings. Applicants should possess a strong background in Earth or Planetary Sciences or related physical sciences, preferably at MSci or MSc level, and demonstrate enthusiasm for laboratory work and analytical research. The application deadline is 14.00 GMT, 25th February 2026. Interested candidates should apply online to the University of Bristol, selecting PhD in Geology as the programme. For further enquiries, contact Prof Tim Elliott at [email protected].