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The Geodiversity of Dawlish

Updated: Dec 17, 2023

The Devon seaside holiday town of Dawlish is a tourism destination throughout the year accessible by road, train or by walking along the South West Coast Path.


Dawlish is also home to Fossil Coast Drinks Co. and maybe unexpectedly Dawlish has an interesting geodiversity that may change your view of its coastal landscape.

Dawlish Fossil Sand Dune System
Dawlish Fossil Sand Dune System Dated to the Permian Period

Dawlish does have a fossil! The red cliffs and stacks of the Dawlish Sandstone Formation in Dawlish is the UK’s best example of a cross-bedded fossil sand dune system dating back to the Permian Period between 298.9 - 251.9 million years ago.



The Dawlish Sandstone Formation is composed of aeolian (air) and fluvial (river water) reddish-brown cross-bedded sands, sandstones, breccia and mudstone formed in deserts.


The Dawlish Sandstone Formation has a special form of interbedding called intercalation where two distinct depositional environments, air and river water, are in close spatial proximity and migrate back and forth across each other.


Arguably, the Dawlish fossil sand dune system ranks among other internationally recognised geological relics including the Al Wathba Fossil Dunes of Abu Dhabi, the fossil dunes of the UNESCO Fundy Biosphere in New Brunswick of Canada and the Fossil Dunes of Ajuy on Jandía in the Canary Islands.


These fossil sand dunes was during the Permian Period. At this time modern day Dawlish was located in the continental interior of the northern hemisphere of the supercontinent of Pangea.


At this time there was no sea and the climate was very hot, dry and deserts were widespread. The harsh conditions of this desert environment meant that life was unsustainable and hence the absence of plant and animal fossils in the Dawlish Sandstone.


Dawlish sits between four UNESCO Sites. To the west is the English Riviera UNESCO Global Geopark; to the north is Exeter City of Literature and the UNESCO North Devon Biosphere and to the east is the Dorset and East Devon Coast or Jurassic Coast the first natural UNESCO World Heritage Site inscribed in the UK over 20 years ago.



Dawlish is demonstrably different in geology from the English Riviera UNESCO Global Geopark that promotes the Devonian Period known as the “Age of Fishes” and is primarily associated with 350 - 400-million-year-old Marine Devonian limestones and more recent Quaternary karstic limestone features such as those seen at Kents Cavern.


The Dawlish Sandstone Formation and fossil sand dune system complements the Dorset and East Devon natural World Heritage Site known as the Jurassic Coast. The most westerly gateway to the Jurassic Coast is Orcombe Point near Exmouth and then it extends for 95 miles towards Old Harry’s Rocks near Swanage in Dorset.


There exists a number of geological differences and several complementarity adjuncts between Dawlish and the westerly gateway to the Jurassic Coast. The Permian Period aged cliffs, coastal stacks and fossil sand dune system of the Dawlish Sandstone Formation intuitively and logically juxtapose itself with the transition between the end of the Palaeozoic Era and the start of Mesozoic Era starting with the Triassic Period at Orcombe Point.



A notable feature of the Mesozoic Era was that it was bookended by mass extinction events starting with the Permian-Triassic (P-Tr boundary) recognised as the largest mass extinction event, known as the “Great Dying”, recorded in the history of life on Earth. The Mesozoic Era ended at the end of the Cretaceous Period with a mass extinction event that saw the demise of the dinosaurs and start of the Paleogene Period and Cenozoic Era.


The Permian Dawlish Sandstone cliffs and stacks complement the natural World Heritage Site of the Jurassic Coast by having a continuous sequence of four geological periods, namely the, Permian, Triassic, Jurassic and Cretaceous spanning two eras in a continuous and unbroken timeline.


Come and visit Dawlish, walk the seawall and take in the scenery of the fossil sand dune system to build an appetite for an Afternoon Tea the Devon way (cream first!).




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