Evidence for biogenic graphite in early Archaean Isua metasedimentary rocks

@article{Ohtomo2014EvidenceFB,
  title={Evidence for biogenic graphite in early Archaean Isua metasedimentary rocks},
  author={Yoko Ohtomo and Takeshi Kakegawa and Akizumi Ishida and Toshiro Nagase and Minik T. Rosing},
  journal={Nature Geoscience},
  year={2014},
  volume={7},
  pages={25-28}
}
The Archaean rocks of Isua, West Greenland, contain graphite, but its origins are debated. Geochemical and microscopic analyses suggest that the graphite was formed from biologically formed carbon that was deposited at least 3.7 billion years ago. 
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