The Ordovician Period

The Ordovician is a period of geological time, approximately 485 to 444 million years ago. Preceded by the Cambrian and followed by the Silurian, it belongs to the Paleozoic Era. The Ordovician was characterised by widespread epicontinental seas, rapid increase in biodiversity and the Hirnantian mass extinction. Read more

Ordovician Chart

The Subcommission on Ordovician Stratigraphy aims to provide accurate and globaly usable time scale for the period, tighten international collaboration and contribute to the understanding of the history of our planet during the Ordovician. Read more