2098 Explore Start
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You can easily see wave cut platforms The Rock of Ages which were formed when sea levels were higher. Extremely jagged rocks This is when our rocks were This is when the big mountain The red sandstones were formed The Earth History Trail fi rst formed. They’re called building period happened, caused during the permian and triassic line the ridge. The ice sheet which ‘Devonian’ – because they by continents colliding - rocks period when a desert or semi arid covered much of Britain in the last ice were fi rst studied here. were folded and compressed. environment covered most of age didn’t come this far south so the Britain and northern Europe. What can you see..? And where..? rocks were subjected to freezing and Start Point thawing causing massive movement of loose material on the surface. Limpet Rocks Torcross Igneous intrusions can be The ruined village of Hallsands is built seen here. Molten rock on wave cut platforms in the mica The rocks beneath your feet help determine the shape of the seeped into gaps in the schist rocks. A protective shingle beach Meadfoot Slates where created by sea level rise after the ice age land, what grows on it and how and where we live. At the coast folding has created cracks. was removed by dredging before the First World War to develop Plymouth the sea has shaped the landscape and also washed away the docks. This made the village vulnerable Castle Cove South Hallsands to storms. In the background you can soil, making it easier to see how the rocks have been formed. see the slate rocks north of the fault. Strete Gate Cliff Slapton Ley FAULT LINE North Hallsands A rocky start There are two types of slate in the Bay: Two freshwater lakes, the Higher and Lower The Dartmouth Slates that run across the older Dartmouth Slates here formed ‘Leys’, are held back by a thin band of shingle The rocks on the outcrop To create the interesting shapes that you can see, over hundreds of millions the middle of the area are visible from by river sediments whereas the Meadfoot beach brought in by rising sea levels after the below the Coastguard of years, rocks were formed, compressed, folded and then weathered. Slates were formed in the sea. the beach. last ice age. The inland shores of the Leys are the You can also see a wave cut cottages are mica schists, The Start Bay rocks date back 400 million years to when much of the area original coastline. platfom here. metamorphic rocks made of the mineral mica. was under a tropical sea and nearer to the equator. Sediment eroded from TORCROSS the land further north settled in river beds on the coastal plain and under the sea – forming ‘sedimentary’ rocks. STRETE Torcross Coast Path The redness of the There is slate all around you on Graphic: A long period of mountain building followed caused by continents colliding. stream suggests © Jurassic Coast Team the coast path heading south This folded the rocks into unusual shapes. The enormous weight piled on by With the right combination haematite (iron oxide) from Torcross! of low tides fossilised – rocks which lie on the mountains compressed the rocks making them harden up and change There are slate fi eld boundaries forest remains can be You are here! both sides of the fault into ‘metamorphic‘ rocks. (the big stones), slate walls, and seen on the beach here, at line running between the even the path is slate. The wave cut platforms at Start Point date from around 150,000 A changing climate North Hallsands and more North Hallsands Beach schists and slates. years ago. The shingle barrier beaches started to form between frequently over at South Blackpool Sands SLAPTON 10,000 and 3,000 years ago, after the last ice age. Over time, the rocks have weathered and the changing climate has also had Milton/ Thurlestone beach. an impact. When the climate was warmer, sea levels were higher and the breaking waves wore fl at areas on the rocks called 'wave cut platforms', as at What makes the Earth History of Start Bay special? Hallsands, which are now above current sea levels. 1. The rocks here are much older than the ‘Jurassic Coast’ and there are ‘cleavage’ with a direction which is usually different from the original The red soils and gently rolling Slapton Ley and Widdicombe Ley lakes were also formed by climate change. many different rock types to see: sedimentary ‘bedding plane’. hills were caused by erosion Beesands Quarry • sedimentary – layers formed from eroded rock fragments washed into • volcanic (igneous) - made from cooled lava sometimes seeping into During the last ice age lots of water was locked up in ice sheets. This made of sandstones in a desert Before the quarry was closed in rivers and the sea – (sandstone, breccia and mudstone). cracks made during folding forming intrusions (basalt, dolerite, tuff). the sea level fall and the coastline move 20 miles further out than it is now. climate (during the Permian 1885 the bluish Meadfoot Slate • metamorphic – during the period of mountain building sedimentary or When the climate warmed, the ice melted making the sea level rise. The sea period). Seasonal fl ash fl oods was used for roofi ng and building 2. The schist rocks at the southern part of Start Bay are the oldest in Devon. Slapton Sands Widdicombe Ley igneous rocks already in place were folded and compressed by the rocks returned, pushing a ridge of shingle before it, which dammed a number of then swept large quantities in the area. Much of the stone was They are separated off by a fault line running through North Hallsands of sediment into the valleys, streams to create the lakes. Slapton Village The pebbles reveal the beach story: the yellow ones are transported by boat from the beach. This freshwater lake at Beesands above (forming slates and schists). The schists are made up of different beach and over to Hope Cove. smoothing the landscape. minerals – in this area mica, which can have a shiny appearance and fl ints or chert which make up nearly three quarters of the Loose material on the south side of was also created by the bank of 3. There is evidence of much more recent climate change: wave cut hornblende which has a grey green appearance. beach material. They come originally from the chalk 20 miles the quarry is the remains of the shingle pushed up by rising sea platforms and the shingle barrier beaches. offshore. The grey pebbles are slates from the local cliffs. spoil heap. levels after the ice age. The pressure causes the minerals in the rock to align into a This panel is part of a series telling the story of the area – Explore Start Bay. Panels and trails can be found along the coastal path around the Bay or by visiting www.explorestartbay.org. Photo credit: Special thanks to This project is run by the Slapton Line Partnership www.slaptonline.org, working with the South Devon Area of Outstanding Natural Beauty Unit. Alan Stapleton for photographs Panel design: luke tom.com If you would like more information on the South West Coast Path National Trail visit www.southwestcoastpath.com. and technical advice.