The BGS Lexicon of Named Rock Units — Result Details

Lenthay Limestone Bed

Computer Code: LEN Preferred Map Code: Len
Status Code: Full
Age range: Bathonian Age (JN) — Bathonian Age (JN)
Lithological Description: Micritic limestone with a shelly and argillaceous base and an extensively bioturbated and argillaceous top. Contains abundant Sphaeroidothyris lenthayensis.
Definition of Lower Boundary: Transition from shell-detrital mudstone to shelly argillaceous limestone.
Definition of Upper Boundary: Transition to calcareous mudstone from argillaceous limestone.
Thickness: 0 - c.1m; 0.32m in Purse Caundle Borehole.
Geographical Limits: Lenthay Common, west of Sherborne, to c.1km northwest of Milborne Port.
Parent Unit: Lower Fuller's Earth Member (LFE)
Previous Name(s): Sphaeroidothyris Bed (-2897)
Lenthay Bed (-2288)
Alternative Name(s): none recorded or not applicable
Type Section  Lenthay Common. Bomb crater (1940) on the west side of Lenthay Copse, Lenthay Common, (Fowler, 1957). 
Reference Section  BGS Purse Caundle Borehole (ST71NW/7) (Barton and others, 1993) (89.13 to 89.45m depth). 
Reference Section  Housing Estate, Lenthay Common. Foundation and drainage trenches on Lenthay Common, exposed 1967 (Torrens, 1968) 
Barton C M, 1989. Geology of the Milborne Port district (Somerset and Dorset) 1:10 000 Sheet ST61NE. Technical Report of the British Geological Survey, Onshore Geology Series, WA/89/60 
Torrens, H S, 1968. 'Geology'. "In" Dorset Natural History Reports 1967. Proceedings of the Dorset Natural History and Archaeological Society, Vol.89, p.42. 
Fowler, J, 1957. The geology of the Thornford pipe-trench. Proceedings of the Dorset Natural History and Archaeological Society, Vol.78, p.51-57. 
Cope, J C W (Editor) 1980b. A correlation of Jurassic rocks in the British Isles. Part Two: Middle and Upper Jurassic. Geological Society of London Special Report, No.15 
Barton, C M, Ivimey-Cook, H C, Lott, G K, and Taylor, R T. 1993. The Purse Caundle Borehole, Dorset: stratigraphy and sedimentology of the Inferior Oolite and Fuller's Earth in the Sherborne area of the Wessex Basin. British Geological Survey Research Report, SA/92/01. 
Bristow, C R, Barton, C M, Freshney, E C, Wood, C J, Evans, D J, Cox, B M, Ivimey-Cook, H C, and Taylor, R T. 1995. Geology of the country around Shaftesbury. Memoir of the British Geological Survey, Sheet 313 (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used: