The BGS Lexicon of Named Rock Units — Result Details
Burtle Formation
| Computer Code: | BUB | Preferred Map Code: | notEntered |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Mid Pleistocene (QPM) — Late Pleistocene (QPL) | ||
| Lithological Description: | Sands and gravels. The sands are fine-grained and quartzose, with beds of comminuted shell. The gravels, which are composed of Chalk flint, quartz, sandstone, cherts, rounded lumps of red, green and grey Triassic mudstones and Liassic fossils, are marine in origin with a few interbedded palaeosols and freshwater sands. They contain fossilised marine, fresh water and terrestrial shells and remains of elephant, rhinoceras, horse, auroch, red, fallow and roe deer, hyaena and wolf. The marine shells indicate both cold and warm water climates and sandy, muddy and rocky habitat, and the freshwater shell Corbicula fluminalis indicates a climate warmer than now. The deposits form low mounds protruding through the surface of the Holocene silts and clays of the Somerset Levels Formation. | ||
| Definition of Lower Boundary: | The formation rests upon Jurassic and Triassic bedrock. It commonly overlies or fringes "reefs" or "islands" of Lower Lias or Late Triassic rocks. | ||
| Definition of Upper Boundary: | At surface, or else overlain by Holocene silts, clays and peats of the Somerset Levels Formation. | ||
| Thickness: | c.5m | ||
| Geographical Limits: | Restricted to the "Somerset Levels" of northeast Somerset. | ||
| Parent Unit: | British Coastal Deposits Group (COAS) | ||
| Previous Name(s): | Burtle Beds [Obsolete Name and Code: Use BUB]
(-4505)
Burtle Sands Beds [Obsolete Name and Code: Use BUB] (-1403) |
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| Alternative Name(s): | Kenn Church Member Middlezoy Member Greylake Member |
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| Stratotypes: | |||
| Type Section | Greylake No.2 Quarry, c.1km northeast of Middlezoy. Campbell et al. 1999 | ||
| Reference(s): | |||
| Kidson, C. 1970. The Burtle Beds of Somerset. Proceedings of the Ussher Society, Vol.2, 189-191. | |||
| Kidson, C, and Haynes, J R. 1972. Glaciation in the Somerset Levels: the evidence of the Burtle Beds. Nature, Vol.239, 380-392. | |||
| Kidson, C, Gilbertson, D D, Haynes, J R, Heyworth, A, Hughes, C E and Wheatley, R C. 1978. Interglacial marine deposits of the Somerset Levels, Southwest England: Boreas, Vol.7, 215-228. | |||
| Green, G W and Welch F B A, 1965. The geology of the country around Wells and Chedder. Memoir of the Geological Survey of England and Wales, Sheet 280. | |||
| Bulleid A, and Jackson, J W. 1942. Further notes on the Burtle Sand Beds of Somerset. Proceedings of the Somerset Archaeology and Natural History Society, Vol. 87 for 1941, 111-116. | |||
| Kidson, C, and Heyworth, A. 1974. The Burtle Beds of Somerset, glacial or marine? Nature, Vol.251, 211-213. | |||
| Campbell, S, Hunt, C O, Scourse, J D, Keen, D H and Croot, D G. 1999. Southwest England. 66-78 in Bowen, D Q (Editor), A revised correlation of Quaternary deposits in the British Isles. Geological Society Special Report No.23. [London: Geological Society.] | |||
| Whittaker A and Green G W. 1983. Geology of the country around Weston-super-Mare. Memoir of the Geological Survey, England and Wales, Sheet 279 with parts of sheets 263 and 295. | |||
| Bulleid, A, and Jackson, J W. 1938. The Burtle Sand Beds of Somerset. Proceedings of the Somerset Archaeology and Natural History Society, Vol. 83 for 1937, 171-195. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E279 E264 E280 | |||