The sites offer exposures of a mid-Purbeck Lagerstätte, fine-grained limestone rock with good conditions for fossilization.[1] These rocks and fossils were deposited after shallow seas receded about 146 million years ago. They record a warm environment of lakes and coastal lagoons, with occasional marine transgressions such as the Cinder Bed. Large fossils are rare, but there are insects of at least four Orders, fish, and crocodilians, also remains of vegetation, including a large tree[2] and Charales.[3] The charophytes, Clavator reidi, may have grown in a lake 1-2m deep or somewhat more.[4]
Teffont Evias Quarry
This includes a pit with a recorded section from the early Jurassic Lias Group up to the Cinder Bed (formerly identified as the boundary between Jurassic and Cretaceous rocks, now regarded as early Cretaceous).[3] With a wealth of fossils this is one of the most important Purbeck Bed localities outside Dorset.[5]
Teffont Evias Lane Cutting
This is a key site in the history of British palaeoentomology;[6] it has produced rare, but well-preserved insects and is the best exposure of the Purbeck beds (Lower Cretaceous, Berriasian c. 144 Ma) for collecting fossil insects.[5] These beds formed the main material for Peter Bellinger Brodie's "Insects in the Secondary Rocks of England", a seminal work and still significant today.[7]
^ abPurbeck Formation - Jurassic-Cretaceous. Lithology, fauna, facies and palaeoenvironments. Geology of the Dorset Coast. Ian West, Romsey, Hampshire and School of Ocean and Earth Science, National Oceanography Centre, Southampton University, Southampton. 2009. http://www.southampton.ac.uk/~imw/purbfac.htm accessed 5 August 2013
^Harris, T.M. 1939. British Purbeck Charophyta. British Museum (Natural History). London, Printed by Order of the Trustees of the British Museum, Issued 22 April 1939. 83 pp + 17 plates. (by Professor Thomas Maxwell Harris). As reported in: Purbeck Formation - Jurassic-Cretaceous. Lithology, fauna, facies and palaeoenvironments. Geology of the Dorset Coast. Ian West, Romsey, Hampshire and School of Ocean and Earth Science, National Oceanography Centre, Southampton University, Southampton. 2009. http://www.southampton.ac.uk/~imw/purbfac.htm accessed 5 August 2013