The BGS Lexicon of Named Rock Units — Result Details

Kinlochlaggan Quartzite Formation

Computer Code: KLLQ Preferred Map Code: KL
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Massive, white, orthoquartzite, feldspathic quartzite and siliceous psammite. Locally prominent white to pink feldspars. Pebbly beds developed locally. Sporadic development of a 'boulder bed' near the top of the formation.
Definition of Lower Boundary: Rapid transitional boundary (quartzite, psammite, semipelite and micaceous psammite) with the underlying Aonach Beag Semipelite Formation. Where psammite is interbedded with semipelite below, boundary is placed where psammite becomes the dominant lithology. Elsewhere boundary is where quartzite replaces semipelite and psammite.
Definition of Upper Boundary: Sharp upper contact placed where quartzite (or 'boulder bed' where present) is abruptly replaced by semipelite, pelite and / or metalimestone / calc-silicate rocks of the Coire Cheap Formation.
Thickness: To 160m
Geographical Limits: Largely confined to the Ardverikie Forest area, sheet 63E (Dalwhinnie), between Aonach Beag [NN 455 740] and the River Spey at [933 571].
Parent Unit: Appin Group (APP)
Previous Name(s): Kinlochlaggan Quartzite [Obsolete Code] (DAKQ)
Alternative Name(s): none recorded or not applicable
Type Section  Crags of Creag an Fhithich immediately north of the A86 at Kinlochlaggan. 
Reference Section  Leabaidh Chrasgach - prominent col 600m south-west of summit of Adnach Beag. 
Robertson, S and Mendum, J R, in press. Lithostratigraphy of the Grampian and Appin Groups in the Dalwhinnie district, sheet 63E, Scotland. British Geological Survey Technical Report. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S063 S054