Stromatolites - Pilbara craton - Western Australia
The Paleoarchean ( /ˌpeɪlɪ.oʊ.ɑrˈkiːən/; also spelled Palaeoarchaean) is a geologic era within the Archaean. It spans the period of time 3600 Ma to 3200 Ma (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 3.46 billion years found in Western Australia) is from this period.
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In horizontal bars are eras; in left column are periods; right column: bold are epochs; not bold not italic are ages; italic are chrons:
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kya = thousands years ago. Mya = millions years ago. * Not officially recognized by the I.C.S.
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