The BGS Lexicon of Named Rock Units — Result Details

Glen App Group [Obsolete Name And Code: Use CLG]

Computer Code: GAP Preferred Map Code: notEntered
Status Code: Index Level
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Consist mainly of greywackes and siltstone with thick conglomerates and graptolitic shales.
Definition of Lower Boundary: Drawn at base of conglomerate of the Glen App Group (base not exposed).
Definition of Upper Boundary: Drawn at conformable upward passage from greywackes and siltstones of the Glen App Group to red-purple mudstones of the Tappins Group.
Thickness: At least 1400 metres (base not seen).
Geographical Limits: Strathclyde, Scotland.
Parent Unit: Not Entered (?)
Previous Name(s): Glen App Conglomerate (-2814)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Glen App, south of the Stinchar Valley, Strathclyde, Scotland. 
Reference(s):
Peach, B N and Horne, J. 1899. The Silurian Rocks of Britain, Volume 1. Scotland. Memoir of the Geological Survey of the United Kingdom. 
Williams, A and others, 1972. A correlation of Ordivician rocks in the British Isles. Geological Society of London Special Report No.3. 
Cameron, I B, Stone, P and Smellie, J, 1986. Geology of the Country around Girvan. Explanation of 1:50 000 sheet. British Geological Survey, Sheet 7, Scotland. 
Greig, D C. 1971. British Regional Geology: the South of Scotland (3rd Edition). (Edinburgh: HMSO for the Institute of Geological Sciences.) 
Walton, E K. 1983. Lower Palaeozoic - Stratigraphy. In Craig, G Y (editor), Geology of Scotland (2nd edition)(Edinburgh: Scottish Academic Press.) 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable