The BGS Lexicon of Named Rock Units — Result Details

Benan Conglomerate Formation

Computer Code: BNC Preferred Map Code: BNC
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Boulder conglomerate.
Definition of Lower Boundary: Locally erosive contact with Stinchar Limestone Formation, basal beds are laterally equivalent to the Superstes Mudstone Formation.
Definition of Upper Boundary: Overlain by Balclatchie Formation.
Thickness: 50-750m
Geographical Limits: North side of the Stinchar Valley, Girvan district. Lower part is lateral equivalent of Superstes Mudstone Formation.
Parent Unit: Barr Group (BARR)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Benan Hill, Kirkland Hill, Auchensoul Hill. 
Reference(s):
Ince, D, 1984. Sedimentation and tectonism in the Middle Ordovician of the Girvan district, north west Scotland. Transactions of the Royal Society of Edinburgh. Earth Sciences, Vol.75 (2), p.225-237. 
Lapworth, C, 1882. The Girvan Succession. Quarterly Journal of the Geological Society of London, Vol. 38, 537-666. 
Williams, A, 1962. The Barr and Lower Ardmillan Series (Caradoc) of the Girvan district, southwest Ayrshire, with descriptions of the Brachiopoda. Memoir of the Geological Society of London, No.3. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S008 S007