Computer Code: |
DB |
Preferred Map Code: |
notEntered |
Status Code: |
Index Level |
Age range: |
Neoproterozoic Era (AZ)
— Neoproterozoic Era (AZ) |
Lithological Description: |
[Obsolete: use ARGY] Well differentiated quartzite and thinly bedded pelite - basal tillite. |
Definition of Lower Boundary: |
Drawn at base of tillite of the Islay Subgroup where it rests conformably on limestone interpreted to belong to the Blair Atholl Sub-Group. |
Definition of Upper Boundary: |
Drawn at conformable upward passage from limestone interpreteted to belong to the Tayvallich Sub-Group to semi-pelitic and psammitic wacke of the Southern Highland Group. |
Thickness: |
Not known. |
Geographical Limits: |
Shetland, Grampian, Tayside, Central Strathclyde, Inner Hebrides, Scotland. Connemara, Mayo, Antrim, Donegal, Ireland. |
Parent Unit: |
none recorded or not applicable
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
Argyll district, Strathclyde, Scotland. |
Reference(s): |
Johnson, M R W, 1983. Dalradian. "In" Craig, G Y. Geology of Scotland, Edinburgh. |
Rast, N, 1963. Structure and metamorphism of the Dalradian rocks of Scotland. "In" Johnson, M R W and Stewart, F H, (Editors). The British Caledonides, Edinburgh, p.123-142. |
Knill, J L, 1963. A sedimentary history of the Dalradian Series. "In" Johnson, M R W and Stewart, F H, (Editors). The British Caledonides, p.99-121. |
Anderson, J G C. 1948. Stratigraphic nomenclature of Scottish metamorphic rocks. Geological Magazine, Vol. 85, 89-96. |
Wilson, H E. 1972. The regional geology of Northern Ireland. (Belfast: HMSO for Geological Survey of Northern Ireland.) 113pp. |
Harris, A L and Pitcher, W S, 1975. The Dalradian Supergroup. "In" Harris, A L, Shackleton, R M, Watson, J, Downie, C, Harland, W B and Moorbath, S. A correlation of the Precambrian rocks in the British Isles. Geological Society Special Report, No.6. p.52-75. Scottish Academic Press, Edinburgh. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |