Mesoarchean

The Mesoarchean (pronounced /ˌmiːzoʊ.ɑrˈkiː.ən/, also spelled Mesoarchaean) is a geologic era within the Archean, spanning 3200 Ma to 2800 Ma (million years ago). The period is defined chronometrically and is not referenced to a specific level in a rock section on Earth. Fossils from Australia show that stromatolites have lived on Earth since the Mesoarchean. The first supercontinent Vaalbara broke up during this time around 2.8 Ga.