Paleoarchean Era

The Paleoarchean (/ˌpeɪlɪ.oʊ.ɑrˈkiːən/; also spelled Palaeoarchaean (Formerly known as early Archean)) is a geologic era within the Archaean. It spans the period of time 3,600 to 3,200 million years ago—the period being defined chronometrically and not referenced to a specific level in a rock section on Earth. The name derives from Greek “Palaios” ancient.
The oldest ascertained life form (well-preserved bacteria older than 3,460 million years found in Western Australia) is from this period. The 1st supercontinent Vaalbara formed during this period.

Stromatolites – Pilbara craton Western Australia

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