The BGS Lexicon of Named Rock Units — Result Details

Auchlyne Formation

Computer Code: AULY Preferred Map Code: AULY
Status Code: Full
Age range: Ediacaran Period (AD) — Ediacaran Period (AD)
Lithological Description: Psammite, micaceous psammite and garnetiferous semipelite, with minor calcsilicate, calcareous garnetiferous semipelite and garnet-hornblende schist, the latter of possible volcaniclastic origin. Psammite dominates in the upper part of the formation, semipelite dominates in the lower part. Locally, muscovite-chlorite-talc schist with included fragments of carbonate, psammite and siliceous semipelite comprises a distinctive unit with a melange-like appearance within the Formation (Pubil Melange Member).
Definition of Lower Boundary: Upper limit of the calcareous semipelite (typically pale green, phengite, chlorite schist) of the Ben Lawers Schist Formation.
Definition of Upper Boundary: Transitional change upwards to schistose muscovite-biotite-garnet semipelite of the Ben Lui Schist Formation.
Thickness: 0-400m?
Geographical Limits: Occurs at the stratigraphical boundary between the Ben Lawers Schist Formation and Ben Lui Schist Formation. Formation outcrops in the area west and northwest of Killin, in and around upper Glen Lyon and Glen Lochay.
Parent Unit: Easdale Subgroup (DBED)
Previous Name(s): Sron Bheag Schist [Obsolete Name And Code: Use AULY] (DBSB)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  Auchlyne West Burn, downstream of Coire Lobhaidh. 
Reference(s):
In preparation. BGS Sheet Description for Sheet 46W (Crianlarich) and 46E (Killin). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable