The BGS Lexicon of Named Rock Units — Result Details

Scar Limestone Member

Computer Code: SCL Preferred Map Code: SCL
Status Code: Full
Age range: Brigantian Substage (CX) — Brigantian Substage (CX)
Lithological Description: Limestone, pale to medium-grey, wavy bedded, crinoidal with fissile uppermost part and shaly partings; styolitic. Fossiliferous, with bands of Siphonodendron junceum, but comparatively unfossiliferous in the south though a bed rich in brachiopods is present at the base in the southern part of the Brough district (Burgess and Holliday, 1979). Nodules of chert are commonly found in this limestone. In the Longcleugh No 1, Allenheads No 1, and Rookhope boreholes an interbedded unit of black pyritic fossiliferous mudstone with sporadic small ironstone nodules in the upper part of the member. Goniatites of the P2a biozone are found in mudstone just above the limestone at Bowlees in Teesdale.
Definition of Lower Boundary: Taken at the sharp base of limestone overlying measures within the Alston Formation; directly underlain locally by dark mudstone, seatearth sandstone or by a coal seam.
Definition of Upper Boundary: Taken at the base of overlying measures within the Alston Formation.
Thickness: 4 to 14.6m.
Geographical Limits: Member within the Alston Formation of the Alston and Lake District blocks in Cumbria, Northumberland and Durham, lying stratigraphically between the Tynebottom (below) and the Five Yard (above limestone members. The limestone is well exposed along the Pennine escarpment, in Teesdale and Weardale.
Parent Unit: Alston Formation (AG)
Previous Name(s): Scar Limestone (-1805)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Disused quarry northeast of Croglin, Cumbria. Arthurton and Wadge, 1981. 
Reference Section  Rookhope Borehole (BGS Reg No NY 94 SW1) Johnson and Nudds, 1996. 
Reference(s):
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). 
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. 
Johnson, G A L and Dunham, K C. 1963. The geology of Moor House. Monographs of the Nature Conservancy No.2. 
Johnson, G A L, Nudds, J R and Robinson, D. 1980. Carboniferous stratigraphy and mineralisation at Ninebanks, West Allendale, Northumberland. Proceedings of the Yorkshire Geological Society, Vol.43, 1-16. 
Johnson, G A L and Nudds, J R. 1996. Carboniferous biostratigraphy of the Rookhope Borehole, Co. Durham. Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol.86, 181-226. 
Trotter, F M and Hollingworth, S E. 1932. The geology of the Brampton District. Memoir of the Geological Survey, Sheet 18. 
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. 
Eastwood,T, Hollingworth, S E, Rose, W C C and Trotter, F M. 1968. Geology of the country around Cockermouth and Caldbeck. Memoir of the Geological Survey of Great Britain, England and Wales, Sheet 23. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E032 E031 E025 E024 E020 E040 E018 E023 E026 E019 E030