The BGS Lexicon of Named Rock Units — Result Details

Inchrory Limestone Formation

Computer Code: INCH Preferred Map Code: SYMB
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Limestone, blue-grey, medium to coarsely crystalline, thin- to medium-bedded, rarely thick-bedded. Chert nodules in parts. Thin interbeds of graphitic to calcareous pelite and semipelite. Amphibolite pods in some areas.
Definition of Lower Boundary: Above Clashnoir Semipelite Formation at lower limit of grey crystalline limestone lithology. In parts grades downwards into semipelites with limestone interbeds.
Definition of Upper Boundary: Upper limit of grey crystalline limestone. Marked change or rarely rapid transition to overlying pelite and semipelite of the Glenfiddich Pelite Formation.
Thickness: 50 - 150m, possibly locally thicker (to 400m) due to folding/faulting.
Geographical Limits: From 3km SSE of Inchrory (Glen Builg) north in Glen Avon to Bridge of Avon. In Braes of Glenlivet and Glen Suie. Scattered outcrops in Glen Markie. In Keith area and Braes of Edingight, Limehillock Quarry areas.
Parent Unit: Blair Atholl Subgroup (DABA)
Previous Name(s): none recorded or not applicable
Alternative Name(s): Lismore Limestone
Stratotypes:
Type Section  Along A939 from Urlarmore turn, to Lime Works Quarry (Creag Chalcaidh). 
Reference Section  Area around Elf House Cave, Upper Glenfiddich - SSW to Drurican. 
Reference Section  Inchrory - Lagganauld section (Allt Roderick), southwards to Sron nam Broc. [E side of Glen Builg] 
Reference(s):
Memoir of the British Geological Survey, Sheet 75, in preparation. 
Thomas, C W, 1989. Application of geochemistry to the stratigraphic correlation of Appin and Argyll Group carbonate rocks from the Dalradian of northeast Scotland. Journal of the Geological Society, London, Vol.146, 631-647. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S075