Research project awarded time on Edinburgh Ion Microprobe to investigate meteorite composition
Access to specialist facilities will support investigations which may shed light on origins of Earth and our solar system.
Professor Hilary Downes and Dr Nachiketa Rai (Leverhulme Post-Doctoral Fellow) have had their application to use the Ion Microprobe Facility (located in the School of Geosciences, Grant Institute, University of Edinburgh) approved. Access to these specialist facilities is worth £7500 to the project which is investigating ureilites, a particular kind of meteorite, to gain insights into the origins of the Earth. Ureilites are made of olivine and pyroxene, similar to the Earth’s upper mantle, but they also contain carbon in the form of graphite, diamond and metals.
Professor Downes explains why understanding ureilites in more detail can reveal much about the early origins of our solar system: ‘Ureilites are commonly thought to be analogues for the processes which formed the early Earth’s core and mantle. Olivines in these meteorites often display reduction rims containing blebs of iron metal. These were produced by a redox process (similar to the process used in blast furnaces for industrial iron making) which reduced FeO in the olivine to Fe-metal in the presence of carbon as a reducing agent.'
'We plan to analyse the ratio of the different isotopes of oxygen in two places inside crystals of olivine (a common mineral often called peridot) . Whether the ratios of the oxygen isotopes are the same or different in the centres and the edges of the olivines will enable us to test two competing ideas about the way in which the olivines were formed. This will help us to understand how asteroids were formed and how they started to acquire the layered internal structure seen in planets like the Earth.’
Professor Downes teaches on a range of Earth and Planetary Sciences programmes, including Mineralogy and Volcanology (CertHE) and Environmental Geology (BSc).