Computer Code: |
STSH |
Preferred Map Code: |
STSH |
Status Code: |
Index Level |
Age range: |
Triassic Period (T)
— Triassic Period (T) |
Lithological Description: |
[Obsolete: use MMG] 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: |
none recorded or not applicable
|
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. |
Holmes, 1899. The geology of the country around Carlisle. Memoir of the Geological Survey. |
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: |
E023
E022
E018
|