Archaean microfossils

Schopf, J.W. (1993). Microfossils of the early Archaean Apex chert. New evidence for the antiquity of life. Science 260, 640-646. 

Late Archaean stromatolites Younger stromatolites have been described from 3.0 Ga rocks at Steep Rock in Canada (Wilks St Nisbet, 1985), from the 2.7 Ga Cheshire formation of the Belingwe Greenstone belt (Martin et al., 1980) and from 2.52 Ga shelf carbonate sediments in the Campbellrand subgroup, South Africa. In this latter locality there are also well-documented calcified microfossils of cyanobacteria (Kazmierczak St Altermann, 2002). It is also possible that at this locality the mineralization of the dead bacteria was the result of the action of het-erotrophic bacteria. 

Schopf, J.W. and Packer, B.M., 1987. Early Archaean (3.3 billion to 3.5 billion-year-old) microfossils from Warawoona Group, Australia. Science, 237, 70-3. 

Buick R (1991) Microfossil recognition in Archean rocks an appraisal of spheroids and filaments from a 3000 M.Y. old chert-barite unit at North Pole, Western Austrdia. Palaios 5 441-459 Buick R (1992) The antiquity of oxygenic photosynthesis Evidence from stromatolites in sulphate-deficient Archaean lakes. Science 255 74-77... 

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