The BGS Lexicon of Named Rock Units — Result Details

Gaick Psammite Formation

Computer Code: GCKP Preferred Map Code: notEntered
Status Code: Full
Age range: Neoproterozoic Era (AZ) — Neoproterozoic Era (AZ)
Lithological Description: Thick sequence of predominantly grey laminated fine-grained quartzose psammite with scattered biotite flakes and laminae. Some darker grey biotitic micaceous psammite interbeds with muscovite on partings. Calc-silicate lenses present and minor quartzite and semipelites near the base of the Formation. Most bedded units are 0.1 to 0.5m thick and some are cross-bedded
Definition of Lower Boundary: Top of the Falls of Phones Semipelite Formation, where the predominant semipelite passes into predominantly feldspathic and quartzose psammites of the GaickPsammite Formation.
Definition of Upper Boundary: Equivalent to the top of the Bruar Psammite Formation (Sheet 55W) i.e. the base of the Tummel Quartzite Formation, where white quartzite units predominate above the predominately psammite succession of the Gaick Psammite Formation.
Thickness: 1 to 2km (but difficult to be precise)
Geographical Limits: Strathspey to Glen Tilt and Glen Garry; widespread within the Strathtummel Basin.
Parent Unit: Strathtummel Subgroup (STEL)
Previous Name(s): Bruar Psammite Formation (BRPS)
Moine "Series" (-3418)
Drumocter Succession (-2818)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Base of the Formation seen in the A9 road cutting near Crubenmore. 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