Devonian Period
Age : 354 to 417 million years ago
Geography, environment and climate
During the Devonian, much of Britain formed part of a large continental landmass that included Greenland, Scandinavia and north-east Canada. In the area occupied by southern England and the Midlands large rivers flowed across an extensive coastal plain transporting large amounts of sediment derived from erosion of mountains to the north and west. The most southerly part of England was occupied by a shelf sea which deepened rapidly to the south.
The climate was semi-arid and the part of the landmass incorporating the British Isles lay to the south of the Equator.
Key events
The Devonian seas were home to many species of fish, shelled relatives of the squid (nautiloids), corals, brachiopods and trilobites. The Devonian continent supported freshwater lakes and rivers with many fish species, the first higher plants, insects and amphibians.
Rock types and occurrence in England
Rocks of the marine Lower and Middle Devonian outcrop in Devon and Cornwall, with warm-water reef limestones predominating in south Devon, deeper water shales and mudstone in Cornwall and shallow water sandstones in North Devon. To the north, sandstones and mudstones of fluvial origin outcrop in the Forest of Dean, Herefordshire and Shropshire.
