Southerham Machine Bottom Pit
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Condition (Natural England)
| Unit | Feature | Condition | Area (ha) | Assessed |
|---|---|---|---|---|
| TQ432089 | — | Unfavourable Declining | 1.82 | 2022-03-30 |
Geology & landscape
Geological Period: Cretaceous · Rock Type: Chalk
Description
Description Southerham Machine Bottom Pit is one of a number of large disused chalk pits on the outskirts of Lewes. An approximately 45 metre thickness of Lower Chalk Chalk Marl, Grey Chalk and Plenus Marls and Middle Chalk Melbourn Rock and Ranscombe Griotte Chalk Member is exposed. The Lewes area has long been famous for the exceptional diversity of fossil fish from its chalk pits. The large collections of fossil fishes from this area were made by famous 19th century scholars including Gideon Mantell and Frank Dixon and were figured in detail by Woodward in his 1902 12 monograph which is still the standard work. Individual species from the Lewes area are frequently represented by large numbers, many of which comprise complete, articulated skeletons without serious distortion. 27 type specimens have been described from the Lewes area most of which are believed to have originated from the Southerham Machine Bottom Pit. These include a diverse fauna of chondrichthyes sharks, skates and rays and osteichthyes bony fish. Notably, eleven of the type specimens represent some of the earliest known neoteleosts, the largest living group of bony fishes. The well preserved and diverse nature of the fossil fishes from Southerham Machine Bottom Pit make this locality particularly important for understanding the early evolution and taxonomy of modern fish groups such as the teleosts as well as providing a detailed insight into the fish communities of the Cretaceous chalk sea.