The BGS Lexicon of Named Rock Units — Result Details

Allt Mor Na H-Uamha Member

Computer Code: TCAM Preferred Map Code: CAM
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Cyclically interbedded "siltstones" and fine- to medium-grained cross-bedded sandstones (the "siltstones" actually consisting of siltstone and very fine- to fine-grained sandstone with subordinate mudstone); the fine- to medium-grained cross-bedded sandstone beds increase in abundance towards the top of the Member.
Definition of Lower Boundary: Base (NM 4205 9722): the "first" (stratigraphically lowest) thickly-bedded,cross-stratified and/or convoluted fine- to medium-grained sandstone bed greater than 2m in thickness.
Definition of Upper Boundary: Top,(NM 4108 9751): the 'first'(stratigraphically lowest) thickly-bedded, cross-stratified and/or convoluted coarse-grained sandstone (arkose) bed containing 'exotic' pebbles characteristic of the Applecross Formation.
Thickness: 415m. in type locality.
Geographical Limits: Isle of Rum, Allt Mor Na H-Uamha.
Parent Unit: Applecross Formation (TCA)
Previous Name(s): Bagh Na H-Uamha Shale (-1221)
Rudha Na Roinne Grit (-1222)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Isle of Rum, Allt Mor Na H-Uamha 
Reference(s):
Black, G P and Welsh, W, 1961. The Torridonian succession of the Isle of Rhum. Geological Magazine, Vol.98, 265-276. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S060