The BGS Lexicon of Named Rock Units — Result Details

Gleann Beag Schist Formation

Computer Code: GBSC Preferred Map Code: symb
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Mostly dark metacarbonate rock and psammite with some graphitic pelite and garnet calcareous schist passing up into graphitic pelite with thin beds of metacarbonate rock.
Definition of Lower Boundary: Base of dominantly calcareous and graphitic rocks. Stratigraphic boundary with the underlying dominantly semipelitic Tulaichean Schist Formation.
Definition of Upper Boundary: Top of dominantly graphitic rocks below the overlying dominantly quartzite succession of the Creag Leacach Quartzite Formation.
Thickness: To 550m
Geographical Limits: Southern part of Sheet 65W (Braemar) and northern part of sheet 56W (Glen Shee).
Parent Unit: Blair Atholl Subgroup (DABA)
Previous Name(s): Glen Beag Schist (-3417)
Blair Atholl Dark Limestone And Dark Schist (-4666)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Gleann Beag area. 
Reference(s):
Crane, A, Goodman, S, Krabbendam, M K, Leslie, A G, Paterson, I B, Robertson, S and Rollin, K, 1996. Geology of the Glen Shee district. Memoir of the British Geological Survey, Sheet 56W and adjacent areas (Scotland). 
Upton, P S, 1986. A structural cross-section of the Moine and Dalradian rocks of the Braemar area. Report of the British Geological Survey, Vol.17, No.1, 9-19. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S056 S065