The BGS Lexicon of Named Rock Units — Result Details

Garron Point Tremolitic Flag Member

Computer Code: GART Preferred Map Code: GarT
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Semipelite, flaggy, calcareous and minor micaceous psammite, green with tremolitic amphibole porphyroblasts prominent in most exposures. Upper part locally contains thin, lenticular bands of metalimestone.
Definition of Lower Boundary: Transition from dominantly bluish and purplish grey calcareous flaggy semipelite to dominantly greenish grey tremolitic lithologies.
Definition of Upper Boundary: Sharp change from tremolitic flags to interbedded graphitic pelite, semipelite and metalimestone of Mortlach Graphitic Schist Member.
Thickness: c.250 to 300m on coast section; not measurable inland.
Geographical Limits: From coast at Garron Point [NJ 5525 6700-5550 6700], as far inland as fault at [NJ 532 633], south of which it is covered by Devonian sedimentary rocks.
Parent Unit: Cairnfield Calcareous Flag Formation (CCFL)
Previous Name(s): Garron Point Actinolitic Schists (-275)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  On coast from west to east side of Garron Point. 
Reference(s):
Stephenson, D and Gould, D , 1995. British Regional Geology: the Grampian Highlands (4th edition). (London: HMSO for the British Geological Survey), 67-68. 
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. 
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. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S096