The BGS Lexicon of Named Rock Units — Result Details

Tynebottom Limestone Member

Computer Code: TBL Preferred Map Code: TBL
Status Code: Full
Age range: Brigantian Substage (CX) — Brigantian Substage (CX)
Lithological Description: Limestone, blue-grey, thick-bedded, planar to wavy-bedded, stylolitic, in part fissile with intercalated thin mudstone beds. Fossiliferous, particularly with abundant corals, brachiopods and crinoid debris. It commonly has a Saccamminopsis band 1.5 to 2m from the top. A bed near the top is characteristically argillaceous and "slaggy" (Johnson and Dunham, 1963).
Definition of Lower Boundary: Taken at the sharp base of limestone overlying measures within the Alston Formation, in places comprising sandstone, elsewhere mudstone.
Definition of Upper Boundary: Taken at the base of overlying measures within the Alstone Formation, here usually comprising up to about 10m of compact, hard, dark grey mudstone colloquially referred to as the Tyne Bottom Plate.
Thickness: 7.6 to 14.6m
Geographical Limits: So-called because it crops out in, or closely underlies, the bed of the River South Tyne between Alston and Tynehead. Well exposed along the Pennine escarpment, in Teesdale and Weardale.
Parent Unit: Alston Formation (AG)
Previous Name(s): Tyne Bottom Limestone (-2476)
Alternative Name(s): none recorded or not applicable
Type Area  High Cup Gill, Dufton Fell, Cumbria. Burgess and Holliday, 1978. 
Reference Section  Rookhope Borehole (BGS Reg No NY94 SW/1). Johnson and Nudds (1996). 
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. 
Trotter, F M and Hollingworth, S E. 1932. The geology of the Brampton District. Memoir of the Geological Survey, Sheet 18. 
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. 
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. 
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 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. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E026 E019 E030 E031 E025 E024 E020 E018 E023