Evidence for biogenic graphite in early Archaean Isua metasedimentary rocks

  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},
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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Graphitic carbons and biosignatures 2 3

<100 words) 87 Unambiguous identification of graphitic carbons as remains of life in ancient rocks 88 is challenging because fossilized biogenic molecules are inevitably altered and 89 degraded

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