Computer Code: |
DBPB |
Preferred Map Code: |
notEntered |
Status Code: |
Index Level |
Age range: |
Neoproterozoic Era (AZ)
— Neoproterozoic Era (AZ) |
Lithological Description: |
[Obsolete: use CAPT, PTSL] Dark grey graphite-schist and kyanite-schist, staurolite-schist, mica-schist, coarse-grained limestone and quartzite as well as tremolite-limestone. (Correlative of Portsoy Group = Carbonaceous Group). |
Definition of Lower Boundary: |
Drawn at base of staurolite schist of Portsoy Group where it rests conformably on quartzite and quartzose, mica-schist of the Durn Hill Quartzite. |
Definition of Upper Boundary: |
Drawn at unconformable upward change from schists of the Portsoy Group to biotite gneiss of the Cowhythe Gneiss. |
Thickness: |
1400m approx. |
Geographical Limits: |
Grampian, Scotland. |
Parent Unit: |
none recorded or not applicable
|
Previous Name(s): |
Carbonaceous Group
(-848)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
Portsoy, Grampian, Scotland. |
Reference(s): |
Read, H H, 1921. The Banffshire Coast section of the Highland Schists. Summary of Progress of the Geological Survey of Great Britain for 1920, p.70. |
Brown, P E. 1983. Caledonian and Earlier Magmatism. 176-177 in Geology of Scotland. Craig, G Y (editor). |
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). |
Harris, A L and others, 1973. A correlation of the Pre-Cambrian rocks in the British Isles. Geological Society of London Special Report No 6. |
Fettes, D J, Lesley, A G, Stephenson, D and Kimbell, S F, 1991. Disruption of Dalradian stratigarphy along the Portsey Lineament from new geological and magnetic surveys. Scottish Journal of Geology, Vol.27, 57-73. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |