Computer Code: |
LAMO |
Preferred Map Code: |
SYMB |
Status Code: |
Full |
Age range: |
Tonian Period (AT)
— Tonian Period (AT) |
Lithological Description: |
Near base: feldspathic psammite and pelite interbedded (5-20 cm scale); siliceous psammite to quartzite interbedded on dm scale with subordinate dark pelite layers; near top pelite with subordinate psammite interbedded on cm scale, with increase of strain. |
Definition of Lower Boundary: |
Conformably upon the Upper Shiaba Psammite Formation (USHP). Transitional boundary, marked by gradual increase of semipelitic beds. |
Definition of Upper Boundary: |
Structually overlain by the Scoor Pelite Formation (Glenfinnan Group), but separated by a shearzone with intense mylonitisation. |
Thickness: |
none recorded or not applicable
|
Geographical Limits: |
Ross of Mull, Isle of Mull, Inner Hebrides. |
Parent Unit: |
Morar Group (MORR)
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Section |
Coastal section on Ross of Mull, Traigh Bhan na Sgurra [NM 424 183 - NM 423 188]. |
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. |
Krabbendam M, Strachan R A, Prave A. 2021. A new stratigraphic framework for the early Neoproterozoic successions of Scotland. Journal of the Geological Society of London. doi:10.1144/jgs2021-054 |
Holdsworth, R E, Harris, A L and Roberts, A M, 1987. The stratigraphy, structure and regional significance of the marine rocks of Mull, Argyllshire, west Scotland, Geological Journal, Vol.22, 83-107. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S043
|