Geology

Devon's Rocks - A Geological Guide

Welcome to our guide to the rocks of Devon. This webpage contains guides to 13 different rock types found in Devon. We hope you find the information provided is appropriate for your requirement, either for leisure or study. Different levels of information is provided, which is designed for those with a general interest in rocks, along with more advanced technical descriptions.

Click on either the map or the rock name in the key below to open a PDF which contains:

  • a basic description of the rock type
  • a more technical explanation of the geology
  • photographs of the rock type
  • how the rock type has been used
  • recommendations of where the rock type can be visited

Also, at the bottom of this page there are links to an ‘Introduction to the Geology of Devon’ and a document called ‘Devon's Rocks - A Geological Guide’ which is a compilation of all 13 rock type guides.

Interactive Summary Map of the Geology of Devon

SUMMARY MAP OF THE GEOLOGY OF DEVON Permian Breccias, Sandstones and Volcanics Tertiary Deposits Tertiary Deposits Permian Breccias, Sandstones and Volcanics Tertiary Deposits Devonian Slates, Sandstones and Volcanics Lower Devonian Schists Transition Group - (Devonian to Carboniferous boundary) Devonian Slates, Sandstones and Volcanics Transition Group - (Devonian to Carboniferous boundary) Carboniferous Sandstones and Shales Carboniferous Sandstones and Shales Tertiary Deposits Dartmoor Granite Devonian Slates, Sandstones and Volcanics Devonian Slates, Sandstones and Volcanics Carboniferous Sandstones and Shales Devonian Limestones Permian Breccias, Sandstones and Volcanics Carboniferous Sandstones and Shales Devonian Limestones Tertiary Deposits Devonian Slates, Sandstones and Volcanics Upper Greensand and Gault Transition Group - (Devonian to Carboniferous boundary) Devonian Limestones Permian Breccias, Sandstones and Volcanics Devonian Limestones Devonian Limestones Devonian Limestones Devonian Limestones Devonian Slates, Sandstones and Volcanics Carboniferous Sandstones and Shales Triassic Pebble Beds, Sandstones and Mudstones Chalk Chalk Chalk Chalk Upper Greensand and Gault Triassic Pebble Beds, Sandstones and Mudstones Upper Greensand and Gault Upper Greensand and Gault Upper Greensand and Gault Upper Greensand and Gault Upper Greensand and Gault Lundy Granite Permian Breccias, Sandstones and Volcanics Permian Breccias, Sandstones and Volcanics Carboniferous Sandstones and Shales Upper Greensand and Gault Lower Jurassic Mudstones and Limestones Lower Jurassic Mudstones and Limestones Lower Jurassic Mudstones and Limestones Lower Jurassic Mudstones and Limestones Permian Breccias, Sandstones and Volcanics

Key to Devon's Principal Rock Types


Quaternary Deposits and Landforms image - PDF icon (315KB - pdf help)
These recent
deposits are
not on the map

Permian Breccias, Sandstones and Volcanics image - PDF icon (466KB - pdf help)
Permian Breccias, Sandstones and Volcanics

Tertiary Deposits image - PDF icon (301KB - pdf help)
Tertiary Deposits
Dartmoor Granite image - PDF icon (383KB - pdf help)
Dartmoor Granite

Lundy Granite image - PDF icon (202KB - pdf help)
Lundy Granite
Carboniferous Sandstones and Shales image - PDF icon (431KB - pdf help)
Carboniferous Sandstones and Shales

Chalk image - PDF icon (438KB - pdf help)
Chalk
Transition Group
(Devonian to Carboniferous boundary)
Transition Group (Devonian to Carboniferous boundary)

Upper Greensand and Gault image - PDF icon (436KB - pdf help)
Upper Greensand and Gault
Devonian Slates, Sandstones and Volcanics image - PDF icon (371KB - pdf help)
Devonian Slates, Sandstones and Volcanics

Lower Jurassic Mudstones and Limestones image - PDF icon (468KB - pdf help)
Lower Jurassic Mudstones and Limestones
Devonian Limestones image - PDF icon (309KB - pdf help)
Devonian Limestones

Triassic Pebble Beds, Sandstones and Mudstones image - PDF icon (322KB - pdf help)
Triassic Pebble Beds, Sandstones and Mudstones
Lower Devonian Schists image - PDF icon (397KB - pdf help)
Lower Devonian Schists

Further Information

Visiting Geological Sites

Devon Rigs     

The information on this page was developed in celebration of the International Year of Planet Earth in partnership with the Devon RIGS Group. The 13 guides to the rock types were written by a team of consultants within David Roche GeoConsulting. The Basic Description sections have been subsequently edited by Devon County Council