Journal article

Decontamination of geological samples by gas cluster ion beam etching or ultra violet/ozone

Graham Purvis, Neil Gray, Naoko Sano, Anders Barlow, Charles Cockell, Geoffrey D Abbott, Cees van der Land, Peter Cumpson



The organic matter within rocks contains chemical and isotopic evidence of its provenance, including information on past and extant life. Such information could further the understanding of life on the early Earth and yield evidence of the existence of past life on Mars. However, the collection of geological samples and subsequent transfer to analytical facilities possibly via long-term storage provides ample opportunity for organic contamination from a variety of sources prior to analysis. Erroneous assignment of organic contamination as authentic indigenous organic material is a significant issue in any geological specimen, but is exacerbated in rocks containing trace levels. This investig..

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University of Melbourne Researchers


Awarded by Engineering and Physical Sciences Research Council

Funding Acknowledgements

The Author is deeply grateful for the bursary generously provided by The Leverhulme Trade Charities Trust without which this project would not be possible. Many thanks also to the IODP Gulf of Mexico repository in Texas for the supply of geological samples, and their kind assistance Thanks to all the team at NEXUS, Newcastle University. X-ray photoelectron spectra were obtained at the National EPSRC XPS Users' Service (NEXUS) at Newcastle University, an EPSRC Mid-Range Facility, and Paul Donohoe for operating the pyrolysis-GCMS.