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| Devonian Period |
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| Age : |
354 – 417 million
years ago |
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| 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. |
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| 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. |
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| 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. |
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