Geology

Geology to see in Eastern Devon

   22.  Orcombe Point to Lympstone
   23.  Budleigh Salterton Cliffs & the Otter Estuary
   24.  Ladram Bay to Sidmouth
   25.  Sidmouth to Beer Coast
   26.  Beer Quarry Caves
   27.  Axmouth to Lyme Regis Undercliffs
   28.  Exeter City Walls & Cathedral
   29.  Brampford Speke
   30.  Killerton Park

22. Orcombe Point to Lympstone

Nearest town: Exmouth
OS grid reference: SY 256896 – SY 323913
Status: AONB, SSSI, SPA,WHS
Management: National Trust, East Devon District Council & private landowners
East Devon District Council - logo
National Trust - logo

Orcombe Point marks the western gateway of the Jurassic Coast World Heritage Site and its oldest rocks, dating from the early Triassic period around 252 million years ago,can be seen here. The dramatic red mudstone and sandstone reveal evidence of a previous desert environment crossed with seasonal life-giving rivers similar to Namibia today. Rare plant fossils have been found here. Of more recent design is the Geoneedle unveiled by HRH the Prince of Wales in 2002 in celebration of the Jurassic Coast World Heritage Site.

Passing westward from Orcombe Point you come to the Maer Local Nature Reserve. This is an area of sand dunes which before the construction of the road along the seafront would have been a landward extension of the bigger dunes on the beach. This sand rests on a raised beach which is 8 to10m above the present beach level.

© Sarah Firth
© Sarah Firth

© Sarah Firth
© Sarah Firth

Low cliffs at the northern end of Lympstone show an exposure of a rock consisting of large angular pebbles, made from a variety of rock types including granite, sandstone, and volcanic rocks. This is known as the Exe Breccia (a word that literally means ‘rubble’) and is the result of torrential flash floods bringing material from mountainous ground to the west.

This stretch of coastline also offers terrific views of the Exe Estuary, a site of international importance for its wildlife.

Facilities:
Toilets, cafés and car parking are available in Exmouth.

Access: Bicycle: Cycle routes from Exeter – Exmouth will be open mid 2008. Bus & Train: Frequent local services run from Exeter to Exmouth. Road: On the A376 to Exmouth, follow signs to the seafront. There is a car park in Lympstone opposite the Swan Inn within easy walking distance of Lympstone pier which is just south of the cliff section. Foot: From Lympstone to Exmouth follow the East Devon Way footpath and from Exmouth to Orcombe Point the path joins up with the South West Coast Path. Please be careful whilst exploring the coastline and refer to the safety notes at the start of this booklet.

Further information: please view www.jurassiccoast.com/index.jsp or www.exe-estuary.org.A copy of the Maer Local Nature Reserve leaflet can be viewed at www.eastdevon.gov.uk/cs-maerleaflet.pdf.

23. Budleigh Salterton Cliffs and the Otter Estuary Easy access routes available

Nearest town: Budleigh Salterton
OS grid reference: SY 055814
Status: AONB, SSSI,WHS
Management: East Devon
Pebblebed Heaths Conservation - logo
CLINTON DEVON ESTATE - logo

The cliffs in the western part of Budleigh Salterton expose the full thickness of the Lower Triassic Budleigh Salterton Pebble Beds.The Beds are made up of well-rounded pink, red and grey cobbles and pebbles that resulted from the erosion of 400 million year old quartzite outcrops lying to the south-west, possibly now under younger rocks in the English Channel or even Brittany.These were laid down as a coarse gravel in a large braided river which crossed a Triassic desert 246 million years ago. Over the years erosion processes have released the pebbles from the bed thus creating the present pebble beach. Some of these pebbles have been carried by the action of the sea as far east as Sussex and Kent.

© Richard Edmonds/Dorset County Council
© Richard Edmonds/Dorset County Council

The Budleigh Salterton Pebble Beds are overlain by red Otter Sandstone which is of mixed wind blown and river origin and can be seen west of the promenade and in low cliffs behind it.At Otterton Point, on the eastern side of the mouth of the Otter Estuary, this sandstone has yielded important fossil remains including ‘the Devon rhynchosaur’, an ancient reptile that has allowed these rocks to be dated to the Triassic period.The Otter Estuary is also important for its modern day wildlife.

Facilities:
There are information boards, viewing platforms, toilets, shops, cafes, a tourist information centre and a car park.When walking along the coastline please take care and refer to the safety guidance at the start of this booklet.

Access: Foot: Access is via the South West Coast Path or along the beach from Budleigh Salterton. Bicycle: There is an Exmouth to Budleigh Salterton cycle route. Easy access on the western side of the estuary. Bus: Buses run regularly from Exmouth and Sidmouth. Train: Train services run to Exmouth. Road: From Exeter, take the A376 to Exmouth and then go west along the B3178 to Budleigh.There is car parking at Budleigh Salterton.

For further information, please view www.jurassiccoast.com or www.devon.gov.uk/geo-bsc image - PDF icon (414KB - pdf help).

24. Ladram Bay to Sidmouth

Nearest town: Sidmouth
OS grid reference: SY 096850 – SY121869
Status: AONB, SSSI,WHS
Management: The National Trust and Clinton Devon Estates
CLINTON DEVON ESTATE - logo
National Trust - logo

The views from Ladram Bay to Sidmouth are some of the most dramatic on the East Devon coastline. Both Ladram Bay and Sidmouth are situated on the Triassic Otter Sandstone. This is the same sandstone which, at depth, is an important oil reservoir at the Wytch Farm Oilfield near Poole.

Among the more impressive sights along this stretch of coast are the sea stacks at Ladram Bay.

© Richard Edmonds/Dorset County Council
© Richard Edmonds/Dorset County Council

The sea hollowed out caves in the relatively soft Otter Sandstone and these, in time and with the further action of the sea, came to form arches of rock separate from the main cliff. Eventually, these arches collapsed, leaving the stacks we see today. The base of the stacks is formed of a harder band of sandstone and this is preventing their complete destruction by the sea.Towards the south-west of the Bay can be seen some pale pipes in the sandstone, a visual echo through time of the roots of plants that managed to survive in the dry Triassic conditions. Within the cliffs below High Peak and Chit Rocks at Sidmouth a number of very rare fossils of Triassic fish, reptiles and amphibians have been found.

At Windgate Cliffs you can head inland to visit Peak Hill and Mutter’s Moor. These sites overlay an interesting geology in their own right. For example, Peak Hill is underlain by flint gravel that was probably left behind following the solution of an original cover of chalk during the early Tertiary period.These sites also make a pleasing diversion for their wildlife and views, with areas of heath and woodland to be enjoyed.

Facilities:
Toilets and cafés are available in Sidmouth.

Access:
Please take care on the coastline and refer to the safety guidance at the start of this booklet.

Foot: One of the best ways to get to Ladram Bay is by following the South West Coast Path from either Budleigh Salterton or Sidmouth. Bus: regular services run between Budleigh Salterton and Sidmouth.The Sidmouth Hopper runs to Peak Hill (summer service). Road: On the A3052, at Newton Poppleford, take the B3178 towards Budleigh Salterton and go through Colaton Raleigh.After one mile, take a left turn at the brick monument signposted Otterton and Ladram Bay. When in Otterton, simply follow the signs to Ladram Bay.

© Crown copyright.All rights reserved. 100019783. 2006
© Crown copyright.All rights reserved. 100019783. 2006

For further information on this site, please view www.jurassiccoast.com or www.devon.gov.uk/geo-lbs image - PDF icon (1.89MB - pdf help) and www.devon.gov.uk/geo-phm image - PDF icon (427KB - pdf help).

25. Sidmouth to Beer Coast

Nearest towns: Sidmouth & Beer
OS grid reference: SY 130873 SY 236899
Status: AONB, SSSI,SAC,WHS
Management: National Trust & private landowners
National Trust - logo

Between Sidmouth and Beer the geology is strongly influenced by a gentle easterly dip in the layers of the rocks that are present.The result is that as you travel east the visible rocks change from those of the Triassic Period (230 million years) to

© Sarah Firth
© Sarah Firth

the more recent Cretaceous (70 million years ago). This reflects the unique ‘walk through time’ that can be experienced along the length of the Jurassic Coast World Heritage Site, of which this is a part.

Just east of Sidmouth are the Triassic Mercia Mudstones and these bring a distinctive red colour to the rocks.They were deposited in temporary lakes and rivers in a desert environment. These mudstones are then capped with yellow Upper Greensand and white Chalk (this from the younger Cretaceous Period;‘Creta’ is Latin for ‘chalk’). Both these rocks were laid down in a marine environment, the chalk mainly consisting of the skeletons and shells of countless numbers of organisms,most of them microscopic. As you move towards Beer the easterly dip increasingly brings the pale sands of the Upper Greensand and its overlying Chalk down to beach level and by Beer Head the entire cliff is taken up by these Cretaceous rocks.

All things being equal, you could expect to see Jurassic rocks lying above the older Triassic material and below the younger Cretaceous deposits. The Jurassic Period began about 206 million years ago. However, you will notice no reference above to Jurassic rocks between the Triassic mudstones and the Greensand and Chalk of the Cretaceous Period – they are missing from the site and have been eroded away. This kind of break in the geological story is known as an unconformity.

Facilities:
There are car parks, toilets, restaurants, shops and pubs in Sidmouth, Branscombe and Beer.

Access:
Foot:
The South West Coast Path runs through this area. Please also refer to the safety guidance at the start of this booklet. Bus: The X53 Bus regularly operates in the area. Road: On the A376 to Exmouth, follow signs to the seafront. Bicycle: There is an inland on-road signed cycle route between Sidmouth and Beer.

For details please view www.nationaltrust.org.uk, www.jurassiccoast.com and further geological information is available at www.devon.gov.uk/geo-sid image - PDF icon (582KB - pdf help).

26. Beer Quarry Caves

Nearest town: Beer
OS grid reference: SY 214895
Status: AONB, SSSI, SAC
Management: Beer Quarry Caves Ltd.
Beer Quarry Caves Ltd. - logo

© Beer Quarry Caves
© Beer Quarry Caves

Beer Quarry Caves provide a fascinating insight into the geology of East Devon, where a unique limestone was formed on the seabed 92 million years ago from a mixture of pulverised shells, fine sand and clay. Beer Stone is ideally suited for fine detail carvings but hardens on exposure to the air and was used in the construction of 24 cathedrals including Exeter,Winchester and St Paul’s, as well as Hampton Court and Windsor Castle.

Conducted tours of these vast underground caverns, which were started by the Romans and worked until the early 20th century, illustrate how

the stone was quarried by candlelight with pick axes and saws, then transported on horse-drawn wagons and by barges which sailed from Beer beach. The Roman chambers (where the roof is supported by typical Roman arches and the walls bear tool marks) now house a small museum. The quarry provided a place of refuge for Catholics during times of persecution and a hiding place for contraband when Beer village was renowned for smuggling. It now provides a winter home to many species of hibernating bats.

© Beer Quarry Caves
© Beer Quarry Caves

Facilities:
Guided tours, extensive free parking, toilets and light refreshments. Open daily Monday before Easter to end October and at other times by prior arrangement.

Access: Foot: Accessible from the South West Coast Path. Road: Follow brown and white tourist signs from A3052 (Sidmouth to Lyme Regis road) off the M5 junction 30 or signs from Beer and Seaton. Bicycle: There are signed on-road cycle routes that run through and around Beer.

Further information:
www.beerquarrycaves.fsnet.co.uk or call 01297 680282.

© Peter Wakely/Natural England
© Peter Wakely/Natural England

27. Axmouth to Lyme Regis Undercliffs

Nearest towns: Seaton & Lyme Regis
OS grid reference: SY 256896 – SY 327912
Status: AONB, SSSI, NNR, SAC, WHS
Management: Natural England
Natural England - logo

This magnificent 304 hectare nature reserve managed by Natural England offers dramatic coastal scenery and is of international importance for its geological and geomorphological features and wildlife, which are well viewed from the beach or even better from a boat.

Travelling from Axmouth to Lyme Regis the rocks get younger, providing a rare opportunity to observe ‘geological time’. In the west, near Axmouth, can be seen 235 million year old red mudstones deposited during the arid Triassic Period; the grey bands are the remains of old salt lakes. Heading east, these are replaced by 195 million year old grey mudstones and limestones of the Lias (the oldest part of the Jurassic Period). These Jurassic sediments were laid down in a warm, shallow tropical sea and can yield the fossils of marine animals.Ammonites are not uncommon

and past discoveries have included marine reptiles such as ichthyosaurs and plesiosaurs. Please leave all in situ fossils for others to enjoy. In places, these rocks are overlain by the more recent sandstones, clays and chalk of the Cretaceous Period, laid down in marine conditions about 70 million years ago.

Extensive and dramatic landslides have also heavily influenced the coastline as you see it today and it is not unusual for the more recent Cretaceous rocks to have slipped down to beach level.

Facilities:
The nearest toilet and refreshment facilities are in Lyme Regis and Seaton.

Access:
Foot:
The South West Coast Path runs through this 7 mile long reserve but it does not provide access to the beach, which may be gained at either Axmouth or Lyme Regis (hazards here include rock fall and high tides). Bus and train: There are regular bus services to Seaton and Lyme Regis, including the ‘Jurassic Bus’ (X53), and bus links to the train station at Axminster. Road: There are public car parks at both Seaton and Lyme Regis. Boat: There are trips from Beer and Lyme Regis.

For further information on this site, please view www.jurassiccoast.com, www.naturalengland.org.uk or www.devon.gov.uk/geo-alu image - PDF icon (1.07MB - pdf help).

28. Exeter City Walls & Cathedral Easy access routes available

Nearest City: Exeter
OS grid reference (Cathedral): SX 921925
Status: Listed buildings / Scheduled Ancient Monument
Management: Exeter City Council, Chapter of Exeter Cathedral & private landowners

Exeter City Council - Logo

Over 70% of the wall that once protected Exeter still remains and reveals a lot about the geology of the local area. Work began on the wall about 1800 years ago by the Romans and the following centuries saw many alterations and repairs, generally using whatever material was to be found nearby. A walk along the walls will reveal a range of different rock types.

The early Roman construction makes use of purplish grey volcanic lava of Permian age (known as ‘trap’), which was partly quarried nearby from the site of the Rougemont Castle. In the Middle Ages repairers used red sandstone or Heavitree Breccia (Permian, again), another stone found locally in Exeter. Local slates and white sandstone can also be seen; possibly even stone left over from the building of the Cathedral was used.

Exeter Cathedral is magnificent and some have claimed that it possesses the most varied geology of any British cathedral. Materials from over 20 different quarries, many of them local, were used in its construction.

The outer and inner Cathedral walls are made of Salcombe Stone, a sandstone quarried from Salcombe Regis in east Devon. Between these walls is a loose filling of the same volcanic trap used in the construction of the City walls. Mines in the chalk at Beer, also on the east coast of Devon, were worked to provide stone for use in some of the Cathedral’s sculptures, as can be seen on the impressive image screen at the front of the building. Further local geology can be seen inside the Cathedral. For example, the pillars supporting the Patteson Pulpit are made of a Devonian limestone that can take a polish and which has been deformed by earth movements such that some of the corals within it appear elongated. It can be found at a number of sites in South West Devon.

© Sarah Firth
© Sarah Firth

Facilities:
Cathedral:Tours available;shop and café on site. Special tours can be arranged by contacting the visitors office.Toilets available for Cathedral visitors. City Walls: information panels have been laid along the walls to highlight the key events that have affected the wall and the people of Exeter. For children there are quizzes and puzzles to solve along the way so bring paper and a pencil with you!

Access: Foot: The Cathedral is open to visitors at set hours. Free guided tours take place from March to October.The City Walls are accessible all year round. Train and Bus: Located in the city centre the Cathedral is easily accessed by sustainable transport. Buses are regular and the city is serviced by Exeter St David’s and Central Train stations which are just a short walk away from the cathedral and the city walls. Bicycle: There are many cycle routes in and around Exeter to the Cathedral. Road: Follow the M5 to Exeter.

For further information on the Cathedral please view www.exeter-cathedral.org.uk or call 01392 285 983. For further information on the city walls, please view www.exeter.gov.uk. More information on Exeter’s geology can be found in Exeter in Stone, an urban geology by Jane Dove and published by Thematic Trails.

29. Brampford Speke

Nearest City: Exeter
OS grid reference: SX 930986
Status: SSSI
Management: Private landowner

This site is an ideal and very pleasant location to see the River Exe as it snakes its way through the Exe Valley, and well demonstrates how a typical meandering river can effect the development of a floodplain. Here, processes of erosion and

© Sue Satchell
© Sue Satchell

deposition are causing the River Exe to cut through the local Permian sandstones.

The river is eroding the banks on the outside bends of the meanders. On the inside bends the river has less force and so deposits sediment, particularly heavier materials such as gravel. By this action the river migrates and lays down a layer of mainly gravelly sediment behind it.At times of very high flow the river spills over its banks and spreads over the floodplain depositing sand and loam over the coarser sediments left by the meandering channel.

© Crown copyright.All rights reserved. 100019783. 2006
© Crown copyright.All rights reserved. 100019783. 2006

Facilities:
There is limited parking for cars and minibuses in Brampford Speke.Toilets and refreshments are available in Brampford Speke. School parties are welcome by arrangement, please contact 01392 841785.

Access:
Foot:
The Exe Valley Way leads across the site and a public footpath leads on to Stoke Canon. Bus: There are a few buses each day from Exeter. Road: This area can be reached by taking the A377 north from Exeter in the direction of Crediton and following a minor road to the village of Brampford Speke.

For further information on this site, please view: www.devon.gov.uk/geo-brs image - PDF icon (272KB - pdf help).

30. Killerton Park Easy access routes available

Nearest City: Exeter
OS grid reference: SS 973007
Status: SSSI
Management: National Trust
National Trust - logo

The area around Killerton shows signs of having experienced high levels of volcanic activity about 285 million years ago. Evidence of this can be seen all around the area from the natural landscape to the local buildings.

The high ground behind Killerton House is made up of purplish tinged basalt lava.This lava poured out on to a rocky and sandy desert floor and probably came up through a series of cracks in the ground rather than through a single vent.

The lava has been quarried for many years providing the material for local buildings such as Killerton Chapel.

Facilities:
There is a shop, refreshments, guided tours, a picnic area, events and routes for walking and cycling available at the site.

Access:
Road:
From Exeter follow the Cullompton road (B318); from M5 northbound, exit J30 via Pinhoe and Broadclyst; from M5 southbound, exit J28. Bus: Regular services from Exeter to Silverton Turn and a 15 min walk to Killerton House. Bicycle: National Cycle Network 52 runs from Pinhoe to Killerton House.

For more information about Killerton House please view www.nationaltrust.org.uk and further geologiocal information is available at www.devon.gov.uk/geo-kil image - PDF icon (452KB - pdf help).

Killerton Chapel © Peter Chamberlain
Killerton Chapel © Peter Chamberlain