Phosphatic Limestones

Phosphatic stromatolites of the ~1.7 Ga Jhamarkotra Formation (Aravalli Group, India),
display twisted Fe-oxide filaments similar to the Fe-biomineralized extracellular stalks of
some chemolithoautotrophic bacteria (Crosby et al., 2014).

Late Paleoproterozoic stromatolites of the Aravalli Supergroup of India display
abundant phosphatized granules intimately associated with organic matter, which have been
proposed as possible phosphatized cells or phosphatized extracellular polymeric substances
(Papineau et al., 2016).


Presence of unique algal stromatolite fossils in the Proterozoic Aravalli dolomitic limestone (~1800 Ma) at Jhamarkotra (N 24° 29’: E 073° 52’) attracted attention of geologists world over. While the presence of life in Vindhyan Formations (~750 Ma) was being debated, the well-preserved, undoubted algal life in Proterozoic was a dazzling discovery.





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