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 [Obsolete Name and Code: Use GART]
(-275)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Section |
On coast from west to east side of Garron Point. |
Reference(s): |
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. |
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
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