The BGS Lexicon of Named Rock Units — Result Details

Stanwix Shales Formation [Obsolete Name And Code: Use MMG]

Computer Code: STSH Preferred Map Code: STSH
Status Code: Index Level
Age range: Triassic Period (T) — Triassic Period (T)
Lithological Description: Red and green micaceous and sandy mudstones carbonate-rich (dolomite) in upper portions. Rare basal mudstone breccias, gypsum and halite locally.
Definition of Lower Boundary: Conformable base resting on either Kirklinton Sandstone or St Bees Sandstone.
Definition of Upper Boundary: Poorly known but appears to be conformably overlain by marine mudstones of Penarth Group in Carlisle area.
Thickness: 300m+
Geographical Limits: Carlisle Basin, BGS sheets 16, 17, 22, 23.
Parent Unit: Mercia Mudstone Group (MMG)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  West bank of River Eden, north of Kirkandrews-on-Eden. 
Reference(s):
Dixon, E E L, Maden J, Trotter, F M, Hollingworth, M A and Tonks, L H. 1926. The geology of the Carlisle, Longtown and Silloth District. Memoir of the Geological Survey of England and Wales. 
Howard, A S, Warrington, G, Ambrose, K, and Rees, J G. 2008. A formational framework for the Mercia Mudstone Group (Triassic) of England and Wales. British Geological Survey Research Report, RR/08/04. 
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. 
Holmes, 1899. The geology of the country around Carlisle. Memoir of the Geological Survey. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E023 E022 E018