| Computer Code: |
MAUP |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Tonian Period (AT)
— Tonian Period (AT) |
| Lithological Description: |
Dominated by siliceous, feldspathic to micaceous psammite, from course to fine grained, locally quartzitic. Commonly pebbly and gritty bands; also semipelitic layers and calc-silicate bands. Abundant cross-bedding and soft-sediment deformation structures. |
| Definition of Lower Boundary: |
Conformably upon the Morar Schists Formation (MAMS). |
| Definition of Upper Boundary: |
Unknown: not exposed. |
| Thickness: |
c. 2500 m (minimum; estimate). |
| Geographical Limits: |
NW Highlands: Ardnamurchan, Morar, Knoydart, Kintail. |
| Parent Unit: |
Morar Group (MORR)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Partial Type Section |
Type section: northern shore of Arnamurchan peninsula [NM 611 691 - NM 548 716]. |
| Reference Section |
Reference section: northern shore of Rhue peninsula: [NM 654 852 - NM 611 848]. |
| Reference(s): |
| Krabbendam, M. 2021. A stratigraphic framework for the early Neoproterozoic successions of the Northern Highlands of Scotland. UK Stratigraphic Framework Series. British Geological Survey Open Report, OR/21/072. 86pp. |
| Bonsor H C, and Prave A R. 2008. The Upper Morar Psammite of the Moine Supergroup, Ardnamurchan Peninsula, Scotland: depositional setting, tectonic implications. Scottish Journal of Geology 44, 1-12. |
| Ramsay, J.G. and Spring, J., 1962. Moine stratigraphy in the Western Highlands of Scotland. Proceedings of the Geological Association, 73: 295-326. |
| Glendinning, N R W. 1988. Sedimentary structures and sequences within a late Proterozoic tidal shelf deposit: the Upper Morar Psammite Formation of northwestern Scotland. 14-31 in Later Proterozoic stratigraphy of the Northern Atlantic regions. Winchester, J (editor). (Blackie.) |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
S061
S061
S062
|
