If you are interested in microfossils, tiny mammal remains, turtle shell fragments, crocodile skin fragments and fish remains, Durlston Bay is ideal. It is also a good location to take samples for wet sieving. Don’t forget your field lens when visiting.
♦ Take the A351 to Swanage. Stay on this road until you get to the seafront. Then, turn right into Shore Road and then into Institute Road. From this road, turn into Seymer Road and finally turn into Durlston Road. You will need to park down Belle Vue Road.
♦ Park in this road and take the footpath that is signposted as the ‘Zig-Zag’ path. This goes between the flats.
♦ The Zig-Zag path will take you to the shore, where you can immediately start looking for fossils.
♦ Ref: 50.60475°N, 1.95079°W
FIND FREQUENCY: ♦♦♦♦ – Durlston does yield many fossils, but most of these are very small and are for the fossil enthusiast, rather than a beginner.
CHILDREN: ♦ – This location can have unpredictable tide conditions. Double tides frequently occur and the sea can be very powerful. The foreshore is also very rocky and access to the beach is difficult. Therefore, this location is not suitable for families with children.
ACCESS: ♦♦♦ – Access to this location is fairly easy, if you use the Zig-Zag path. This has now been re-opened after being closed as a result of a landslide.
TYPE: – Most fossils can be found on the foreshore, especially after storms, but they are also commonly found in the cliff. In particular, they can be found in the Mammal Bed, which is at the base of the cliff. Take home samples for analysing later.
This site is part of the Jurassic World Heritage Coastline, so please follow the Fossil Code of Conduct. This is also a SSSI, so no hammering of the cliff or bedrock is allowed. Damage has already been caused to the heritage site by people using power tools. This is strictly against SSSI rules and any attempt to ignore them may result in prosecution.
Within the dark banded freshwater Mammal Bed, fragments of bone are common, which are compacted within the soft black and grey layers. Fragments of crocodile, fish and turtle are very common, with other mammals also being found here. However, the bones are extremely fragile, so it is best to leave them within the shale and then extract and preserve them when home. An ideal way to collect here is to take several bags of samples home and wet sieve. Small teeth can also be found using this method, but make sure you sieve at 0.5mm, since many of the teeth will fall through anything wider than this mesh.
At the west side of Durlston Bay, the hard limestone rocks yield crocodile, turtle, mammal, fish and reptile remains and the occasional crustacean. Although less common than in the shales of the Freshwater Marly Bed, fossils in the limestone are much better preserved. They also tend to be less fragmented.
The beds are rich in microfossils, including some very rare small mammals, and also forams and ostracods. You can take back samples for sieving at home, but you will need a microscope and sieve with a 500 micron mesh.
Towards the middle of Durlston Bay, the Mammal Bed reaches the foreshore. This can be seen sandwiched between two hard limestone layers. There is then a thin black layer, followed by a grey layer, then a very thick second black layer and a lighter grey layer resting on top of the lower limestone.
Mammal remains can be found within the harder limestone, but these are rare. It is much easier to search through the shale. The Mammal Bed can easily be recognised by the colour and the number of freshwater shells in it. Note that the beds suddenly dip in the middle of Durlston Bay and run for a while along the foreshore. This is the point at which the Mammal Bed reaches the level of the beach.
To the west of Durlston Bay, mammal remains are more common within the hard limestone rocks on the foreshore. Sharks and fish remains can also be found, along with crustaceans and reptiles.
The top beds at Durlston Bay are from the Purbeck. In fact, the site is the type locality for the Purbeck Limestone Group. Large boulders from this can be seen all over the foreshore. Broken Shell limestone can often be seen on the foreshore near the Zig-Zag path. This is a hard, massive limestone with fragments of fish and turtles, along with the gastropods, Neomiodon and Viviparus, and the bivalve, Unio. Below the Broken Shell Bed and the Chief Bed, there is approximately 8m of limestones separated by shales. The first part of this bed is full of gastropods (Promathildia, Hydrobia and Procerithium). The Scallop Beds follow this.
Below the Chief and Scallop beds are the Intermarine Beds. These are over 15m thick and include many limestones and thinner alternating bands of shale. The shale yields fish and turtle remains. Below this, the Cinder Bed forms the base of the Durlston Formation, which is full of oyster shells and bivalves. Below this is the Cherty Freshwater Bed from the Lulworth formation, which yield many gastropods and, beneath this, is the Marly Freshwater Bed, which marks the location of the Mammal Bed. This Marly Freshwater Bed, which is 4m thick, is full of gastropods (Valvata and Hydrobia). The Mammal Bed is in the middle of this section, where turtle crocodile and fish remains can be found. Insects have also been recorded from this horizon. The Soft Cockle Bed follows. There is some 22m of this bed, which contains a large amount of gypsum. The Hard cockle Bed is below this. There is 4m of this, in which cockles are tightly compacted.
Common sense when collecting at all locations should be used and prior knowledge of tide times is essential. There are four tides a day here. Care should be especially taken at the two headlands. The sea nearly always reaches the cliffs and the rocks can be very slippery. Care should also be taken of falling rocks, as the cliffs are extremely unstable. Landslips are always possible here and the ground beneath your feet, if climbing the slopes, could give way at any time.
There are two different rock types that fossils can be collected from – the dark shale and hard limestone. For that reason, it is best to take a range of tools, including hammers and, most essentially, a field lens. It is also worth taking some preserving liquid for fragile fossils.
This site is an SSSI and forms part of the UNESCO World Heritage Jurassic Coast. This means you can visit the site, but hammering the bedrock is not permitted. For full information about the reasons for the status of the site and restrictions please download the PDF from Natural England – SSSI Information – South Dorset