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 [Obsolete Name and Code: Use KNHG]
(-4132)
Uppermost part of Whitehills Group [Obsolete Name and Code: Use KNHG] (-4133) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Section | Coastal section from Craig Neen, Whitehills to east side of Knock Head (western end of Boyndie Bay). | ||
| Reference(s): | |||
| 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). | |||
| 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. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| S096 S096 | |||