The BGS Lexicon of Named Rock Units — Result Details

Strathan Conglomerate Member

Computer Code: STRC Preferred Map Code: notEntered
Status Code: Full
Age range: Tonian Period (AT) — Tonian Period (AT)
Lithological Description: Metaconglomerate with heterogeneous clasts (quartzite, gneiss, vein quartz, quartz-magnetite rock, granite/pegmatite) in a green-grey psammite matrix. Occurs in two units, separated by psammite. The metaconglomerate is strongly sheared.
Definition of Lower Boundary: Unconformable upon Lewisian Gneiss inlier (L); unconformity highly sheared.
Definition of Upper Boundary: Conformably overlain by the remainder of the Altnaharra Psammite Formation (ALPS).
Thickness: c. 20 m (estimate of deformed rocks).
Geographical Limits: Northern Highlands: Sutherland: Ben Hutig to East Strathan.
Parent Unit: Altnaharra Psammite Formation (ALPS)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Type area at Traigh an t-Strathain [NC 57 64]. 
Reference(s):
Holdsworth, R E, Strachan, R and Alsop, G I. 2001. Solid geology of the Tongue district; Memoir for 1:50 000 Geological Sheet 114 E (Scotland),British Geological Survey, Keyworth, Nottingham. 
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. 
Mendum, J R. 1976. A strain study of the Strathan Conglomerate, North Sutherland. Scottish Journal of Geology 12, 135-146. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S114