Britannica
Sources used in this answer
When did the Ordovician Period begin and end?
Created from Britannica articles
using AI.
AI can make mistakes, so verify using Britannica articles.
Ordovician Period
The distribution of landmasses, mountainous regions, shallow seas, and deep ocean basins during the Ordovician Period. Included in the paleogeographic reconstruction are the locations of the interval's subduction zones.
The Ordovician Period began 485.4 million years ago and ended 443.8 million years ago. It followed the Cambrian Period and preceded the Silurian Period.1