Stromatolite Record: Archean

Stratigraphy: The Stomatolite Record

Archean: In the beginning there was rocks

Archean Banded Iron Formation with stromatolitc laminations (www.academic.emporia.edu)

earliest known stromatolites originated from several localities, and date from 3.5 BA, (Warrawoona Group of Western Australia)
generally are rare in the Archean. geologically, the Archean environment did not favour the development or the preservation of stromatolites

sites of deposition were commonly fault-controlled volcanic -sedimentary basins (greenstone belts) that accumulated thick extrusive volcanic sequences and rapidly deposited sediments
the high rate of sedimentation would overrun the rate of microbial mat development
sediments accumulated faster than the microbes could grow or migrate to the sediment-fluid interface
carbonates, which commonly form in tectonically stable environments were also uncommon in the Archean
without this environment, the probability of preservation is unlikely, the only Archean samples have been found in cherts and banded iron formations.

Pillinging Tuff, cut face shows a microbioherm (Walter, 1972)

Proterozoic.....