From a report submitted by Robin Haller, University of Glasgow.
This project aimed to study the effects of terrestrial weathering on CM chondrites of different petrologic type with the help of laboratory experiments. For the experiments, eighteen chips of the meteorites Chwichiya 002, Murchison and Kolang were reacted with artificial rainwater under oxidising conditions for 30 and 180 days. The research grant from the Meteoritical Society helped to fund the analytical methods needed to study the results of the experiments, which included the analysis of reacted solutions (leachates) by ICP-OES and IC and meteorite surfaces by SEM/EDS. The experiments were conducted in collaboration with the Department of Environment and Geography at the University of York for which parts of the grant were highly appreciated to fund travel and analytical methods. Thin sections were made from some reacted meteorite chips of interest to study the effects of terrestrial alteration in more detail. As the meteorite chips were all fairly small (~100 mg each), the thin sections needed to be fabricated by an external specialist for which some funds of the research grant were used.
Especially the SEM work on the meteorite chip surfaces and the ICP-OES were of great use for the project and also for the personal academic development of the grant recipient. Results of the experiments were used to validate and support kinetic weathering models and built the foundation for a PhD thesis chapter and a research paper.
Research paper “The effect of terrestrial weathering on the mineralogy and petrologic (sub)types of CM chondrites explored by kinetic modelling and laboratory experiments” published 2026 in Meteoritics and Planetary Science by Robin L. Haller, Martin R. Lee and Mark E. Hodson.