Imperial College London
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ProfessorMarkSephton

Faculty of Engineering, Department of Earth Science & Engineering

Professor of Organic Geochemistry
 
 
 
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Contact

 

+44 (0)20 7594 6542m.a.sephton Website

 
 
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Location

 

2.34Royal School of MinesSouth Kensington Campus

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Summary

 

Publications

Citation

BibTex format

@article{Sephton:2023:10.1111/MAPS.13952,
author = {Sephton, M and Chan, Q and Watson, J and Burchell, M and Spathis, V and Grady, M and Verchovsky, A and Abernethy, F and Franchi, I},
doi = {10.1111/MAPS.13952},
journal = {Meteoritics and Planetary Science},
title = {Insoluble macromolecular organic matter in the Winchcombe meteorite},
url = {http://dx.doi.org/10.1111/MAPS.13952},
year = {2023}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - The Winchcombe meteorite fell on 28th February 2021 in Gloucestershire, UK. As the most accurately recorded carbonaceous chondrite fall, the Winchcombe meteorite is an opportunity to link a tangible sample of known chemical constitution to a specific region of the solar system whose chemistry can only be otherwise predicted or observed remotely. Winchcombe is a CM carbonaceous chondrite, a group known for their rich and varied abiotic organic chemistry. The rapid collection of Winchcombe provides an opportunity to study a relatively terrestrial contaminant-limited meteoritic organic assemblage. The majority of the organic matter in CM chondrites is macromolecular in nature and we have performed non-destructive and destructive analyses of Winchcombe by Raman spectroscopy, online pyrolysis-gas chromatography (pyrolysis-GC-MS), and stepped combustion. The Winchcombe pyrolysis products were consistent with a CM chondrite, namely aromatic and polycyclic aromatic hydrocarbons, sulfur-containing units including thiophenes, oxygen containing units such as phenols and furans, and nitrogen-containing units such as pyridine; many substituted/alkylated forms of these units were also present. The presence of phenols in the online pyrolysis products indicated only limited influence from aqueous alteration, which can deplete the phenol precursors in the macromolecule when aqueous alteration is extensive. Raman spectroscopy and stepped combustion also generated responses consistent with a CM chondrite. The pyrolysis-GC-MS data is likely to reflect the more labile and thermally sensitive portions of the macromolecular materials while the Raman and stepped combustion data will also reflect the more refractory and non-pyrolyzable component, hence we accessed the complete macromolecular fraction of the recently fallen Winchcombe meteorite and revealed a chemical constitution that is similar to other meteorites of the CM group.
AU  - Sephton,M
AU  - Chan,Q
AU  - Watson,J
AU  - Burchell,M
AU  - Spathis,V
AU  - Grady,M
AU  - Verchovsky,A
AU  - Abernethy,F
AU  - Franchi,I
DO  - 10.1111/MAPS.13952
PY  - 2023///
SN  - 1086-9379
TI  - Insoluble macromolecular organic matter in the Winchcombe meteorite
T2  - Meteoritics and Planetary Science
UR  - http://dx.doi.org/10.1111/MAPS.13952
UR  - https://onlinelibrary.wiley.com/doi/10.1111/maps.13952
UR  - http://hdl.handle.net/10044/1/102664
ER  -
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