Mendips header
 Overview maps
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  Cheddar Gorge
 Burrington Combe
 Shipham & Rowberrow
 Crook Peak & Axbridge
 Banwell to Churchill
 Harptree & Smitham Hill
 Draycott & Westbury-sub
 Wookey Hole & Ebbor
 Great Elm & Vallis Vale
 Mells & the Wadbury Valley
 The Vobster area
 The Whatley area
 Torr Works & Asham Wood
 Beacon Hill
 Stoke St Michael & Oakhill
 Holwell & Nunney
 Shepton Mallet & Maesbury
 Gurney Slade & Emborough
 The Nettlebridge valley
 Rocks of Mendips
 Geological timescale
 Ancient environments
 Geological structure
 Minerals and mines
  Minerals and mines
 Industrial archaeology
  Stone as a resource
 Employment & the economy
 Quarrying & geodiversity
 Quarrying & the environment
 History of quarrying
 Caves and karst
 How caves form
 Dry valleys and gorges
 Dolines and sinkholes
 Mendip caves
 Going caving
  Flora and fauna
 Typical Mendip habitats
 Special Mendip habitats
 Horseshoe bats
 Appendix of names
 Biodiversity of western
 Biodiversity of eastern
 External links
 Detailed site information
  Coal mining
  Mendip quarry companies
  East Mendip quarries
 Biodiversity of eastern
  West Mendip quarries
 Biodiversity of western
 Site map
Ancient Environments
Silurian l Devonian l Carboniferous l Triassic l Jurassic

Life in the Late Carboniferous, 326 – 299 million years ago

In the Late Carboniferous, quartzitic sandstones spread across the Mendip area, ending the growth of the Early Carboniferous limestone succession. Eventually a vast delta was formed, stretching from Britain eastwards to Poland, crossed by a winding network of river channels, and colonised by lush swamp forests of giant tree ferns. Decaying plant remains formed thick peat deposits, and these were deeply buried, compacted, and transformed into coal.

At Kilmersdon and Writhlington, near Radstock, discarded rock from coal mining contains the exquisite remains (stems, foliage & seed pods) of fossil plants such as Lepidodendron and Calamites, and more rarely, insects. Unlike modern trees, there was no woody tissue to support these plants. Some grew as featureless trunks, only producing a tree-like crown of branches when fully mature. Others, such as Calamites, resembled the modern-day horsetails, but grew to perhaps 10 m in height.

Periodically, the sea flooded into the coal swamps, killing the vegetation and depositing thin beds of mudstone containing marine fossils. These are called 'marine bands', and are very useful for understanding the relative ages of coal-bearing rocks.
  Life in the Late Carboniferous

Each marine band contains particular fossils that allow its recognition, and are individually named, usually after a particularly characteristic fossil. Near Westbury-sub-Mendip, the Subcrenatum Marine Band has been recognised, characterised by the goniatite Gastrioceras subcrenatum. Goniatites resemble ammonites that inhabited the seas of the Jurassic and Cretaceous, but are more primitive, typically with globose shells and simplified ornamentation.

Life in the Early Carboniferous

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