second era of the Archean eon

The Palaeoarchaean (Paleoarchean) is the second geological era in the Archaean eon. It began 3.6 billion years ago and ended 3.2 billion years ago.[1] Before it was the Eoarchaean and after it was the Mesoarchaean.

The name comes from the Greek word palaios. Palaios means "ancient". The oldest fossil life forms are cyanobacteria found in strata 3.46 billion years old. These rocks are in Western Australia.

The first supercontinent, Vaalbara, formed during this period.


  1. "International Chronostratigraphic Chart" (PDF). International Commission on Stratigraphy. Retrieved 6 July 2013.