The BGS Lexicon of Named Rock Units — Result Details

Askham Limestone Member

Computer Code: ASKL Preferred Map Code: AskL
Status Code: Full
Age range: Asbian Substage (CR) — Brigantian Substage (CX)
Lithological Description: Limestone, dark grey, well-bedded, wackestone and packstone, porcellanous in parts. Prominent layers with algal oncoliths and coral colonies. The member is split into 2 leaves by a thin layer of red-brown mudstone.
Definition of Lower Boundary: Sharp base of limestone bed on the underlying Wintertarn Sandstone Member.
Definition of Upper Boundary: Taken at the base of overlying shelly marine mudstone within the Alston Formation Yoredale depositional cycle.
Thickness: 12 - 14.7m.
Geographical Limits: North Cumbria and Edenside, west of the Pennine-Dent Fault Zone.
Parent Unit: Alston Formation (AG)
Previous Name(s): Askham Limestone (-3179)
Alternative Name(s): Rough Limestone
Stratotypes:
Type Section  Abandoned roadside (east side of minor road) quarry beside Wintertarn Farm, by Shap, Cumbria. Rowley (1969) 
Reference Section  Flusco Lodge disused quarry; entrance off A66, 3.8km west of the M6 Penrith interchange. McCormac (2001). 
Reference(s):
Arthurton, R S, and Wadge, A J. 1981. Geology of the country around Penrith. Memoir for geological sheet 24. Institute of Geological Sciences, London, HMSO. 
Rowley, C R. 1969. The stratigraphy of the Carboniferous Middle Limestone Group of West Edenside, Westmorland. Proceedings of the Yorkshire Geological Society, Vol.37, 329-350. 
Burgess, I C and Holliday, D W. 1979. Geology of the country around Brough-under-Stainmore. Memoir for 1:50 000 geological sheet 31 and parts of sheets 25 and 30. Geological Survey of Great Britain (England and Wales). [London: HMSO.] 131pp. 
Dunham, K C. 1990. Geology of the Northern Pennine Orefield, Vol.1. Tyne to Stainmore, (2nd edition) Economic Memoir of the British Geological Survey, Sheets 19 and 25, parts of 13, 24, 26, 31, 32 (England and Wales). 
McCormac, M, 2001. The Upper Palaeozoic rocks of the Shap and Penrith district, Edenside, Cumbria. British Geological Survey Research Report, RR/01/10. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E030