Potential evidence of fossilised Neoproterozoic deep life: SEM observations on calcite veins from Oppaminda Creek, Arkaroola, South Australia

International Journal of Earth Sciences - Tập 98 - Trang 327-343 - 2007
Paul D. Bons1, Michael Montenari2, Ronald J. Bakker3, Marlina A. Elburg4
1Mineralogie und Geodynamik, Institut für Geowissenschaften, Eberhard Karls Universität Tübingen, Tübingen, Germany
2Earth Sciences and Geography, Keele University, Keele, UK
3Mineralogie und Petrologie, Institut fürAngewandte Geowissenschaften und Geophysik, Montanuniversität Leoben, Leoben, Austria
4Vakgroep Geologie en Bodemkunde, Universiteit Gent, Gent, Belgium

Tóm tắt

Scanning electron microscopy revealed micron-sized globular and coccoid objects, associated with filaments and mucus-like patches in antitaxial fibrous calcite veins from Oppaminda Creek, Northern Flinders Ranges, South Australia. Chemically the objects only differ from their calcite (CaCO3) matrix by a higher sulphur content. The ∼585 Ma veins formed at about 3–6 km below the surface. Fluid inclusions indicate a temperature of formation of about 60–80°C, and not exceeding 100°C. A non-biogenic origin of the objects is discussed, but considered unlikely. Instead, morphology, chemistry and size distribution all indicate that the objects are fossilised microbes that lived in the veins at the time and depth of vein formation.

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