The BGS Lexicon of Named Rock Units — Result Details
Ford Formation
Computer Code: | FML | Preferred Map Code: | FORD |
---|---|---|---|
Status Code: | Full | ||
Age range: | Guadalupian Epoch (PUG) — Lopingian Epoch (PUL) | ||
Lithological Description: | Dolomite that comprises three distinct facies: shelf-edge reef that separates a broad belt of back-reef and lagoonal beds to the west from a belt of fore-reef talus aprons and off-reef beds to the east. | ||
Definition of Lower Boundary: | The incoming of oolitic and pisolitic or reef equivalent dolostone above the fine-grained dolostone of the Raisby Formation. Boundary is transgressive, overlapping older Permian formations to lie unconformably on Carboniferous rocks. | ||
Definition of Upper Boundary: | Either the sharp, conformable base of the overlying anhydrites of the Hartlepool Anhydrite Formation or the reddish-brown mudstone and siltstone of the Edlington Formation | ||
Thickness: | 1 - 150m, generally 100 - 120m | ||
Geographical Limits: | Durham province, County Durham, Tyne and Wear, Cleveland and northernmost North Yorkshire. | ||
Parent Unit: | Zechstein Group (ZG) | ||
Previous Name(s): | Ford [Magnesian Limestone] Formation
(-911)
Middle Magnesian Limestone [Obsolete Name And Code: See FML] (MMGL) |
||
Alternative Name(s): | Sprotbrough Member |
||
Stratotypes: | |||
Type Area | Ford Quarry and Claxheugh Rock, South Hylton, Sunderland, Tyne and Wear, for reef and back-reef facies. Smith, D B et al. 1986, p. 14; Smith, D B. 1995, p. 58. | ||
Reference(s): | |||
Smith, D B, 1995. Marine Permian of England. Geological Conservation Review Series No. 8. [London: Chapman and Hall.] | |||
Smith, D B and Francis, E A. 1967. Geology of the country between Durham and West Hartlepool. Memoir of the Geological Survey of Great Britain, Sheet 27 (England and Wales). | |||
Smith, D B, Harwood, G M, Pattison, J and Pettigrew, T H. 1986. A revised nomenclature for Upper Permian strata in eastern England. 9-17 in Harwood, G M and Smith, D B (editors). The English Zechstein and Related Topics. Geological Society Special Publication No.22. | |||
Smith, D B, 1994. Geology of the country around Sunderland. Memoir of the British Geological Survey, Sheet 21, (England and Wales). | |||
Smith, D B, 1970. The palaeogeography of the English Zechstein. "In" Rav, J L and Dellwig, L F. (Editors). Third Symposium on Salt, Northern Ohio Geological Society, Vol.1, 20-23. | |||
Smith, D B, 1981. The Magnesian Limestone (Upper Permian) reef complex of north-eastern England. "In" Toomey, D F. (Editor). European Fossil Reef Models. Special Publication of the Society of Economic Palaeontologists and Mineralogists, Tulsa, Vol.30, 161-186. | |||
1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
E033 E021 E027 E032 E041 E042 E026 E015 |