| Computer Code: |
NSAL |
Preferred Map Code: |
SYMB |
| Status Code: |
Full |
| Age range: |
Neoproterozoic Era (AZ)
— Neoproterozoic Era (AZ) |
| Lithological Description: |
Striped/banded semipelite and pelite, part calcareous, with numerous limestone bands. Calc-silicate lenticles common in north. Thin dolomite bands also. South of River Don flaggy semipelites and micaceous psammites dominant and carbonate rare. |
| Definition of Lower Boundary: |
Rapid transition downwards to banded psammite-semipelite sequence (Ladder Hills Formation); south of River Don overlies Tornahaish Formation semipelite with carbonate. |
| Definition of Upper Boundary: |
Lower limit of quartzite of Kymah Quartzite Formation or gradation to banded psammite-semipelite sequence (+ volcaniclastic horizons) of Ladder Hills Formation. |
| Thickness: |
Maximum 1310m. Probably duplicated by folding - more likely thickness c. 500m. |
| Geographical Limits: |
Ladder Hills area. Extends from Kymah Burn section southwest to Littleglen Burn and Water of Nochty, then SSE to Ernan Water, Donside and Glen Fenzie (Sheet 75E only). |
| Parent Unit: |
Islay Subgroup (DBIS)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Lower part of Allt Slochd Chaimbeil and upper part of Water of Nochty (upstream of junction with Allt Chuirn Deirg). |
| Reference Section |
Upper part of Allt na Gaothain upstream of A939 road. |
| Reference Section |
Ernan Water section southeast of Rock Ernan and west of Craig Aighean. |
| Reference(s): |
| Memoir of the British Geological Survey, Sheet 75, in preparation. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
S075
|
