The BGS Lexicon of Named Rock Units — Result Details

Knock Head Grit Member

Computer Code: KNHG Preferred Map Code: KnHG
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Interbedded psammite, locally pebbly, semipelite and pelite in graded units. Finer-grained beds metamorphosed to slates, phyllites and mica-schists. Minor calc-silicate pods. Contains andalusite, cordierite and locally staurolite porphyroblasts.
Definition of Lower Boundary: Change from calcareous semipelite and psammite to non-calcareous psammite-dominated lithologies at top of Whitehills Grit Formation; commonly marked by change to locally coarsely gritty psammite.
Definition of Upper Boundary: Transition to graded units with greater proportion of semipelite. Psammites only rarely pebbly.
Thickness: c.0.5km; relatively little repetition by folding.
Geographical Limits: From Moray Firth coast [NJ 6514 6564-NJ 663 654], southwards to northern margin of Aberchrder Granite [NJ 630 530].
Parent Unit: Macduff Formation (MCD)
Previous Name(s): Knock Head Grit (-4132)
Uppermost Part Of Whitehills Group (-4133)
Alternative Name(s): none recorded or not applicable
Type Section  Coastal section from Craig Neen, Whitehills to east side of Knock Head (western end of Boyndie Bay). 
Stephenson, D, et al. 1993. Stratigraphy and correlation of the Dalradian rocks of the East Grampian Project area. British Geological Survey Technical Report WA/93/91. 
Harris, A L, Haselock, P J, Kennedy, M J and Mendum, J R, 1994. The Dalradian Supergroup in Scotland, Shetland and Ireland. 33-53 in Gibbons, W E and Harris, A L (editors). A revised correlation of Precambrian rocks in the British Isles. Special Report of the Geological Society, London, No.22. 
Stephenson, D and Gould, D , 1995. British Regional Geology: the Grampian Highlands (4th edition). (London: HMSO for the British Geological Survey), 67-68. 
Read, H H, 1923. Geology of the country around Banff, Huntly and Turriff, Lower Banffshire and north-west Aberdeenshire. Memoir of the Geological Survey, Scotland Sheets 86 and 96 (Scotland). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S096 S096