It should be noted that the beach is made of fine gravel called pea grit, small WORLD HERITAGE COAST rounded pea size or slightly larger LOCATIONS: pebbles. The beach here forms the western end of and moving BURTON BRADSTOCK east the gravel gets progressively coarser especially when you get east of SPECTACULAR CLIFFS . Visits to the beach at AND FOSSILS. Abbotsbury, Ferrybridge and will show marked change in size of the beach material. The pebbles are made of very hard silica material called flint and chert. This does not come from the local cliffs but has been moved along the coast by a process called long shore drift.

USEFUL RESOURCES: Maps: Ordnance Survey 1:25,000 Outdoor Leisure 15, Purbeck and South .

British Geological Survey Map Sheet 327 .

Books: Geology of the Dorset. John C.W. Cope. Geologists’ Association Guide No 22. The picture above shows differential Coast and Country Geological Walks in and weathering and erosion in the cliff due to around Dorset. DGAG variation in cementing calcium carbonate in the sandstone. Mesozoic Fossils. British Museum (Natural History). This book is very useful for Email: [email protected] identifying many of the fossils found along the Dorset Coast and East Coast.

Websites: ©Alan Holiday 2018 dorsetgeologistsassociation,org jurassiccoast.org Burton Cliff looking SE towards Portland southampton.ac.uk/~imw WHAT’S SPECIAL HEALTH & SAFETY: 900 metres down in east Dorset and The cliffs along this section of coastline are forms one of the reservoir rocks for the ABOUT THE COAST AT relatively high and vertical. Cliff falls are Wytch Farm Oilfield located under and to quite frequent especially during the winter. the south of Harbour. BURTON BRADSTOCK? This is because the sea breaks against the base of the cliffs during storms and they are Above the Bridport Sand, which is up to undercut. The cliffs also have many vertical 25 metres thick here, there is a thin layer, joints which can cause sections to fall. about 4 metres, of Inferior Oolite. This is Burton Cliffs are approximately 30 metres highly fossiliferous and has many high and expose the bright orange Bridport At high tide especially in stormy conditions interesting features. Small round grains in Sand seen in the picture on the front cover. some of the sediment show it is an oolitic These are capped by extremely fossiliferous waves break against the base of the cliff and so the best time to walk along the beach is limestone normally formed in shallow Inferior Oolite and grey Frome Clay or tropical seas and forming now in places Fuller’s Earth Clay. The complete sequence during a falling tide in quiet conditions. Access to the beach can also be gained by such as the Bahamas. Many types of of rocks is seen if you walk about 1 km. west fossils occur in this limestone with a from the National Trust car park. following the cliff path NW to Burton Freshwater and walking SE along the beach number of species of ammonites, nautilus, belemnites, brachiopods, and bivalves. HOW TO GET THERE: for about 0.5 km where the fossiliferous strata can be seen in fallen blocks on the The best time to collect these is after a 1. Location: Burton Cliffs which extend beach. cliff fall when fresh rock is to be found at from GR SY 491888 NW to Burton beach level. Freshwater at GR SY 477895. THE GEOLOGY: Inferior Frome Faul Oolite The rocks exposed at the base of the cliff Clay t Access is gained via the minor 2. are the Lower Jurassic (Upper Lias) road off the B3157 as you approach Bridport Sands. These sands were Bridport Frome Burton Bradstock village from Weymouth, deposited in relatively shallow tropical Sand Clay Portesham and Abbotsbury. Parking is seas approximately 180 million years ago. available in the National Trust car park They contain few fossils, but the The very top of the cliff is capped by grey where the minor road reaches the beach occasional ammonite and belemnite can at SY491888. clay, the Frome Clay, previously called the be found as well as burrows called trace Fuller’s Earth Clay. This can be studied in fossils, i.e. traces where animals have the cliff falls but can also be seen to the 3. Facilities. Parking is available been. The rocks are fine sands which are throughout the year. The National Trust east of the National Trust café and the car quite soft and partially cemented with park. The presence of the clay at beach Café is open in the summer everyday but calcium carbonate. The bedding is in the winter period opening is more level rather than at the top of the 30 metre apparent in the sandstone as weathering high cliff is due to a geological fault which restricted. Toilets are available at the café has picked out the weaker, less well and also in Burton Bradstock. has lowered the clay on the east side of cemented, layers while the better the fault by around 60 metres. The fault Convenience shops and pubs are also cemented layers show honeycomb coincides with the valley (due to a line of available in the village. weathering, with a very pockmarked weakness) used by the minor road to surface. The rocks dip gently to the east reach the sea. and Bridport Sand is found at depth, some