The BGS Lexicon of Named Rock Units — Result Details

Bay Of Stoer Formation

Computer Code: TAS Preferred Map Code: TAS
Status Code: Full
Age range: Stenian Period (AI) — Mesoproterozoic Era (AX)
Lithological Description: Main formation: red, coarse pebbly sandstone, thick bedded, abundant cross bedding and with soft-sediment deformation structures. Thinner beds of mudstone and thin-bedded mudstone-sandstone alternations. Volcaniclastic sandstone (Stac Fada Member) and mudstone (Poll' a Mhuilt Member) at top of formation.
Definition of Lower Boundary: Conformably overlies the Clachtoll Formation(TAT).
Definition of Upper Boundary: Conformably overlain by the Meall Dearg Formation (TAD)
Thickness: At Stoer: 240 m maximum, of which top 100 m is Pollt a' Mhuilt Member. Near Loch Maree, c. 1000 m.
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
Type Section  Coastal section along Bay of Stoer 
Stewart, A D. 2002. The later Proterozoic Torridonian rocks of Scotland: their sedimentology, geochemistry and origin. Geological Society Memoir. Vol. 24. (The Geological Society.) 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S107 S091