| Computer Code: |
GBPE |
Preferred Map Code: |
SYMB |
| Status Code: |
Full |
| Age range: |
Neoproterozoic Era (AZ)
— Neoproterozoic Era (AZ) |
| Lithological Description: |
Biotite-andalusite schist, grey, coarse-grained, highly magnetic; forms prominent "tombstone-like" outcrops. |
| Definition of Lower Boundary: |
Junction of magnetic biotite-andalusite schist with underlying quartzite of the Grumack Hill Quartzite Member (Blackwater Formation). |
| Definition of Upper Boundary: |
Upper limit of coarse-grained biotite-andalusite schist outcrops and/or limit of magnetic anomaly at base of semi-pelites of Clashindarroch Formation. |
| Thickness: |
To 150m |
| Geographical Limits: |
Watershed ridge on SE side of River Deveron valley between NJ 441 351 and Auchmair NJ 405 312. |
| Parent Unit: |
Clashindarroch Formation (CLAS)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Outcrops along crest of Grumack Hill, northeast of Garnel Burn. |
| Reference(s): |
| 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: |
|
S075
S085
S086
|
