The BGS Lexicon of Named Rock Units — Result Details

Torr Na Truim Semipelite Formation

Computer Code: TTRS Preferred Map Code: notEntered
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Semipelite, composed mainly of muscovite, biotite, quartz and feldspar, schistose and locally gneissose, with subordinate thin psammite, quartose semipelite and micaceous psammite bands. The psammite bands become more common towards the overlying Creag Dhubh Psammite Formation.
Definition of Lower Boundary: Not seen, cut out to the southeast by the Glen Truim Fault Zone
Definition of Upper Boundary: Base of the Creag Dhubh Psammite Formation, where a predominantly schistose semipelite belonging to the Torr na Truim Semipelite Formation.
Thickness: To 750m
Geographical Limits: Southwest of Newtonmore, between the Creag Liath Fault and Glen Truim Fault Zone (Sheet 64W).
Parent Unit: Corrieyairack Subgroup (GRCO)
Previous Name(s): Moine Series (-4042)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Outcrops of the upper part of the Formation occurring east of Torr na Truim, a hill on the west side of Glen Truim and south of the River Spey Leslie, A G et al., BGS Internal Report IR/03/048 
Reference(s):
Leslie, A G, Krabbendam, M and Smith, R A, 2003. Progress Report on the Geology of 1:50 k Sheet 64W (Newtonmore) British Geological Survey Internal Report, IR/03/048. 23pp. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable