Computer Code: |
MORR |
Preferred Map Code: |
notEntered |
Status Code: |
Full |
Age range: |
Tonian Period (AT)
— Tonian Period (AT) |
Lithological Description: |
Psammite, originally thick-bedded and cross-bedded, now commonly flaggy, commonly feldspathic; micaceous psammite; semipelite - locally garnefirous; locally massive pelite beds. In norhtern Sutherland commonly gneissose. |
Definition of Lower Boundary: |
Unconformable upon Lewisian Gneiss inlier (L); unconformity highly sheared. |
Definition of Upper Boundary: |
Unknown: highest levels are intruded or sheared by Sgurr beag Thrust. Possibly, the unit was originally unconformably overlain by the Glenfinnan Group. |
Thickness: |
c. 4000-9000 m (estimate: strongly deformed). |
Geographical Limits: |
Northern Highlands. |
Parent Unit: |
Wester Ross Supergroup (WROS)
|
Previous Name(s): |
Morar Division [Obsolete Name And Code: Use MORR]
(MA)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
none recorded or not applicable |
Reference(s): |
Krabbendam, M, Prave, A P and Cheer, D. 2008. A fluvial origin for the Neoproterozoic Morar Group, NW Scotland; implications for Torridon - Morar group correlation and the Grenville Orogen Foreland Basin. Journal of the Geological Society of London, 165, 379-394. |
Bonsor, H C, Strachan, R A, Prave, A, and Krabbendam, M. 2010. Fluvial braidplain to shallow marine transition in the early Neoproterozoic Morar Group, Fannich Mountains, northern Scotland. Precambrian Research 183, 791-804. |
Bonsor, H, Strachan, R, Prave, A, and Krabbendam, M. 2012. Sedimentology of the early Neoproterozoic Morar Group in northern Scotland: implications for basin models and tectonic setting. Journal of the Geological Society of London 169, 53-65. |
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. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
S094
S094
S071
S072
S072
S108
S081
S082
S082
S083
S043
S092
S092
S093
S093
S101
S102
S102
S103
S108
S061
S109
S115
S061
S062
S114
|