Computer Code: |
TCDL |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Neoproterozoic Era (AZ)
— Neoproterozoic Era (AZ) |
Lithological Description: |
Laminated dark-grey "shales" (actually consisting of laminated mudstone, siltstone, and very fine- to fine-grained sandstone), with intercalated beds of pale grey fine-grained sandstone that increase in thickness and abundance towards the top of the member. |
Definition of Lower Boundary: |
Highly variable gradational and/or interdigitating transition from the underlying Fiachanis Gritty Sandstone Member. (NM 3730 9366 or NM 3695 9905). |
Definition of Upper Boundary: |
The 'first' (stratigraphically lowest) thickly-bedded, cross-stratified and/or convoluted fine- to medium-grained sandstone bed greater than 2 metres thick. (NM 4186 9604). |
Thickness: |
275m minimum in type-locality (stratigraphical base not visible). |
Geographical Limits: |
Isle of Rhum, Laimhrig. |
Parent Unit: |
Diabaig Formation (TCD)
|
Previous Name(s): |
Bagh Na H-Uamha Shale
(-1221)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
Isle of Rhum, Laimhrig. |
Reference(s): |
Black, G P and Welsh, W, 1961. The Torridonian succession of the Isle of Rhum. Geological Magazine, Vol.98, 265-276. |
Nicholson, P, 1991. NERC/BGS mapping contract F60/62/38 Geological Mapping Sheet 60, Isle of Rhum. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S060
|