The BGS Lexicon of Named Rock Units — Result Details

Meall Dearg Formation

Computer Code: TAD Preferred Map Code: TAD
Status Code: Full
Age range: Stenian Period (AI) — Stenian Period (AI)
Lithological Description: Pale-red sandstone with bed thickness between 0.3 and 5 m; abundant planar cross-bedding; locally wave-rippled. Locally rare pebble beds.
Definition of Lower Boundary: Conformably overlies the Poll a ' Mhuilt Member (TASP). Marked by incoming of red sandstone, with erosive base.
Definition of Upper Boundary: Not exposed - eroded. Unconformably overlain by Torridon Group (TC).
Thickness: 240 m (minimum).
Geographical Limits: Occurs on several headlands (Stoer peninsula, Rubha Coigach) and near Gairloch, in the NW Highlands, east of the Coigach Fault, and west of the Moine Thrust.
Parent Unit: Stoer Group (TA)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Coastal section between Rubh' a' Mhill Dheirg and Balchladich Bay, Stoer Peninsula 
Reference Section  east side of Achnahaird Bay, Enard Bay. 
Reference(s):
Gracie, A.J. and Stewart, A.D., 1967. Torridonian sediments at Enard Bay, Ross-shire. Scottish Journal of Geology, 3: 181-194. 
Stewart, A D. 2002. The later Proterozoic Torridonian rocks of Scotland: their sedimentology, geochemistry and origin. Geological Society Memoir. Vol. 24. (The Geological Society.) 
Krabbendam, M. 2021. A stratigraphic framework for the early Neoproterozoic successions of the Northern Highlands of Scotland. UK Stratigraphic Framework Series. British Geological Survey Open Report, OR/21/072. 86pp. 
Parnell, J., Mark, D., Fallick, T.E., Boyce, A. and Thackrey, S., 2011. The age of the Mesoproterozoic Stoer Group sedimentary and impact deposits, NW Scotland. Journal of the Geological Society of London, 168: 349 - 358. 
Lebeau, L E, and Ielpi, A. 2017. Fluvial channel-belts, floodbasins, and aeolian ergs in the Precambrian Meall Dearg Formation (Torridonian of Scotland): Inferring climate regimes from pre-vegetation clastic rock records. Sedimentary Geology, Vol. 357, 53-71. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S107 S091