Deep water cuspate stromatolites in the Cryogenian Trezona Formation, South Australia

O’Connell, Brennan1, Wallace, Dr Malcolm W.1, Hood, Dr. Ashleigh v.s.1, Rebecchi,Luke1

1University of Melbourne, , Australia

Deep water stromatolite horizons are well developed in the Cryogenian Trezona Formation and were deposited in an open marine, mid- to outer-ramp setting. Stromatolite horizons predominantly occur in association with shales that contain intraclastic horizons interpreted as mass flow deposits, and are associated with iron oxides and irregular surfaces of erosion. These stromatolite horizons—developed as elongate structures with cuspate mm-scale laminae—are interpreted as condensed sections in sediment starved settings. Documentation of these deep water stromatolites adds to a small collection of deep water stromatolites, which appear to be largely represented by cuspate forms. Deep water stromatolites could be linked to specific redox environments such as anoxic/suboxic ferruginous waters, and/or may be related to carbonate saturation, sediment starvation, or other factors.


Brennan is a PhD candidate at the University of Melbourne.

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