The BGS Lexicon of Named Rock Units — Result Details

Broughton Moor Formation

Computer Code: BMR Preferred Map Code: BMr
Status Code: Full
Age range: Ashgill Series (OA) — Ashgill Series (OA)
Lithological Description: Interbedded nodular and bioturbated micritic limestones.
Definition of Lower Boundary: Unconformable, but local evidence of continuous deposition from the underlying Torver Member with an horizon of chamositic ooliths at the junction passing up in places into a thin, laminated black shale in the lower part of the Broughton Moor Formation.
Definition of Upper Boundary: Sharp and conformable with the overlying Appletreeworth Formation.
Thickness: From 4 m to 6 m thick.
Geographical Limits: The outcrop extends from Limestone Hill in the east (NY 3405 0044) to Hobkin Ground Wood (SD 2297 9125) near Broughton Mills in the west. It is about 4 m thick across its whole outcrop so is too narrow to show on 50k map sheets, but is shown combined with the Appletreeworth Volcanic Formation on the 25k special Sheet of Coniston Fells.
Parent Unit: Dent Group (DNT)
Previous Name(s): White Limestone Member (-1366)
Alternative Name(s): none recorded or not applicable
Type Section  Broughton Moor, east of High Pike Haw. Scott & Kneller, 1990. 
Kneller, B C, Scott R W, Soper N J, Johnson E W and Allen P M, 1994. Lithostratigraphy of the Windermere Supergroup, Northern England. Geological Journal, Vol. 29, 219-240. 
McNamara, K J. 1979. The age, stratigraphy and genesis of the Coniston Limestone Group in the southern Lake District. Geological Journal, 14, 41-69. 
Marr, J E. 1916. The Ashgillian succession in the tract of land to the west of Coniston Lake. Quarterly Journal of the Geological Society of London 71, 189-204. 
Scott, R W and Kneller, B C, 1990. A report on the Ashgill and Llandovery age rocks of Sheet 38 (Ambleside). British Geological Survey Technical Report WA/90/63. 
1:50K maps on which the lithostratigraphical unit is found, and map code used: