The BGS Lexicon of Named Rock Units — Result Details

Sturminster Pisolite Member

Computer Code: STP Preferred Map Code: StP
Status Code: Full
Age range: Oxfordian Age (JO) — Oxfordian Age (JO)
Lithological Description: Pisoliths or oncoliths, about 6mm diameter, varying from spherical to oblate, in a coarse-grained oolitic matrix; locally the matrix is an oolitic clay. In places the pisoliths/oncoliths form a grain-supported concentrate.
Definition of Lower Boundary: Usually sharply defined by an abrupt incoming of large numbers of pisoliths/oncoliths.
Definition of Upper Boundary: Usually sharply defined by the abrupt disappearance of pisoliths/oncoliths.
Thickness: 0.1 - 2m
Geographical Limits: Across the Shaftesbury Sheet (313) and southern part of Wincanton Sheet (297).
Parent Unit: Stour Formation (STOU)
Previous Name(s): Pisolite Facies (-4349)
Pisolitic Beds (-3058)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  East Stour Borehole (ST82SW/9) from 21.64m to 24.19 depth. 
Type Section  Road section on the south side of the A357, 170m at 250 degrees from Newton Bridge. 
Reference(s):
Gutmann, K, 1970. The Corallian Beds at Todber and White Way Hill in north Dorset. Proceedings of Dorset Natural History and Archaeological Society, Vol.91, p.123-133. 
Wright, J K, 1980. Oxfordian Correlation Chart. "In" Cope, C J W, (Editor). A correlation of Jurassic rocks in the British Isles, Part two: Middle and Upper Jurassic. Geological Society of London Special Report No.15. (p.61-76 in Correlation Chart). 
Bristow, C R, 1989. Geology of Sheets 71NE and 71SE. (Marnhull-Sturminster Newton, Dorset) Part of 1:10,000 Sheet 313 (Shaftesbury). British Geological Survey Technical Report WA/89/59. 
Blake, J F and Huddleston, W H 1877. On the Corallian rocks of England. Quarterly Journal of the Geological Society of London, Vol.33, 260-405. 
Freshney, E C. 1989. Geology of Sheets ST70NW and ST70NE. (Hazelbury Bryan-Mappowder district, Dorset). British Geological Survey Technical Report WA/90/51. 
Wright, J K, 1981. The Corallian rocks of north Dorset. Proceedings of the Geologists' Association, Vol.92, 17-32. 
Bristow, C R, 1990. Geology of the West Stour - Cucklington district. British Geological Survey Technical Report WA/90/48. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E297 E313