The BGS Lexicon of Named Rock Units — Result Details

Acuminata Beds

Computer Code: ACU Preferred Map Code: Bdn
Status Code: Full
Age range: Bathonian Age (JN) — Bathonian Age (JN)
Lithological Description: Shell-detrital mudstones with abundant Pracexogyra acuminata. NOTE: Map code 'Bdn' combines Acuminata Beds with Bowden Way Beds.
Definition of Lower Boundary: Transition from calcareous mudstone of the Bowden Way Beds to shell-detrital mudstone.
Definition of Upper Boundary: Transition from shell-detrital mudstone to argillaceous limestone (Fullers' Earth Rock).
Thickness: 5.58 metres (Purse Caundle Borehole).
Geographical Limits: Central Dorset to Gloucestershire.
Parent Unit: Lower Fuller's Earth Member (LFE)
Previous Name(s): none recorded or not applicable
Alternative Name(s): Ostrea Acuminata Beds
Stratotypes:
Type Section  British Geological Survey Purse Caundle Borehole ST71NW/7, Church Farm, Purse Caundle, 26.40 to 31.98m depth. 
Reference(s):
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). 
Welch, F B A and Crookall, R, 1935. British Regional Geology. Bristol and Gloucester district 69. 
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 
Arkell, W J and Donovan, D T. 1952. The Fuller's Earth of the Cotswolds and its relation to the Great Oolite. Quarterly Journal of the Geological Society of London, Vol.107, 227-253. 
Penn, I E, 1982. Middle Jurassic stratigraphy and correlation of the Winterborne Kingston Borehole, Dorset. 53-76 in Rhys, G H, Lott, G K and Calver, M A (editors), The Winterborne Kingston Borehole, Dorset, England. Report of the Institute of Geological Sciences, No.81/3. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E313