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While features of some stromatolites are suggestive of biological activity, others possess features that are more consistent with abiotic (non-biological) precipitation. [17] Finding reliable ways to distinguish between biologically formed and abiotic stromatolites is an active area of research in geology.
Ancient giant stromatolites used to be widespread in Earth’s Precambrian era, which encompasses the early time span of around 4.6 billion to 541 million years ago, but now they are sparsely ...
The Gunflint Chert is composed of biogenic stromatolites. [3] At the time of its discovery in the 1950s, it was the earliest form of life discovered and described in scientific literature, as well as the earliest evidence for photosynthesis. [4] The black layers in the sequence contain microfossils that are 1.9 to 2.3 billion years in age.
Stromatolites are layered biochemical accretionary structures formed in shallow water by the trapping, ... as agents of biological nitrogen fixation, and, ...
Most archean stromatolites older than 3.0 Ga are found in Australia or South Africa. Stratiform stromatolites from the Pilbara Craton have been identified in the 3.47 Ga Mount Ada Basalt. [ 59 ] Barberton, South Africa hosts stratiform stromatolites in the 3.46 Hooggenoeg, 3.42 Kromberg and 3.33 Ga Mendon Formations of the Onverwacht Group .
Collenia Temporal range: 2400–2100 Ma Pha. Proterozoic Archean Had. Siderian - Rhyacian Section of Collenia undosa stromatolite from 2110 million year old banded iron formation, Biwabik Collenia undosa stromatolite from Precambrian of United States Scientific classification Domain: Bacteria Phylum: Cyanobacteria Family: Spongiostromata Subfamily: Stromatolithi Genus: † Collenia Walcott ...
The surface biofilm is the layer that provides the effective purification in potable water treatment, the underlying sand providing the support medium for this biological treatment layer. As water passes through the hypogeal layer, particles of foreign matter are trapped in the mucilaginous matrix and soluble organic material is adsorbed .
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