The Palaeoarchaean (Paleoarchean) is the second geologicalera in the Archaean eon. It began 3.6 billion years ago and ended 3.2 billion years ago. 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.