Kimmeridge

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The Flats in Kimmeridge Bay - a wave-cut platform.

Panorama showing the soft shale cliffs and hard dolomite ledges of Kimmeridge bay. The folly can be seen in the background.

Jurassic shale cliffs at Kimmeridge.

Fossilised Ammonite embedded in rock on the beach at Kimmeridge.

Kimmeridge is a small village in the Purbeck district of Dorset, England, situated on the English Channel coast. The village has a population of 110 (2001).^[1] Non-resident parking is managed by the nearby Smedmore Estate.

The village stands on Jurassic shale cliffs, and gives its name to the division of the Jurassic period in which the beds were laid down, because of the quality of the cliffs and the fossils they yield. It is part of the Jurassic Coast World Heritage Site because of the quality and variety of geological landforms along the coast. There is a Jurassic Coast Visitor Centre at Kimmeridge.

The Bay is also the Type locality for the Jurassic age Kimmeridge Clay formation, that is well-represented in southern England, and provides one of the source rocks for hydrocarbons found in the Wessex and North Sea Basins.

Beneath the cliffs there is a large wave-cut platform (known as The Flats) and a rocky shore, with good quality rock pools and variety of rocky shore wildlife. Kimmeridge coast is usually warm, and perfect for studying seaweed and other organisms. The top, middle and lower beaches are not easily definable without markings, but these are relatively easy to place.

On the cliff toward the west is the BP "nodding donkey" oil pump which has been pumping continually since the late 1950s, making it the oldest working oil pump in the world. The well currently yields around 65 barrels per day^[2] from the Middle Jurassic strata that lie around 350 metres below the cliff.^[3] The well has been operating for this long because it has tapped into a network of connected reserves, although the yield is decreasing year on year. The oil is transported by tanker to the main BP site at Wytch Farm.^[2]

Directly east of Kimmeridge bay (above Hen Cliff) is a folly known as Clavell Tower which inspired P.D. James's novel The Black Tower. Because it was in danger of falling down the eroding cliff, the tower has been dismantled and will be reassembled a safe distance from the cliff edge.

Kimmeridge Bay is a surf area of some renown. Although it breaks infrequently due to its lack of exposure to Atlantic swells when it is on it produces walls of water that surfers will travel hundreds of miles to ride. Below the cliffs to the East is 'The Ledges', slow left and right hand breaking waves which can be enjoyed by all. To the West is 'Broad Bench', within the MOD firing range and only accessible when the ranges are open to the public (hardly ever!), this break can have perfect right handers which spiral for 70 yards or more into the bay. The spiritual home of South coast surfing, this classic reef is for expert surfers only.

[edit] See also

[edit] References

James P D (1975) The Black Tower, Sphere books (1987 edition), 288pp, ISBN 072-215110-1.
Wignall P (ed) (1995) Benthic Palaeoecology of the Late Jurassic Kimmeridge Clay of England (Special Papers in Palaeontology series), Palaeontological Association, 74pp, ISBN 090-170242-0.
Kimmeridge Bay; Geology of the Wessex Coast by Ian West