The BGS Lexicon of Named Rock Units — Result Details

Grain Burn Member

Computer Code: GRAB Preferred Map Code: GRAB
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Porphyritic lavas of hawaiite/mugearite composition.
Definition of Lower Boundary: Conformable base of lavas on pyroclastic rocks within Peat Rig Formation along Grain Burn.
Definition of Upper Boundary: Conformable top of lavas below pyroclastic rocks within Peat Rig Formation along Grain Burn.
Thickness: c.100m
Geographical Limits: Bail Hill area, 4km north west of Sanquhar, Dumfries, Scotland.
Parent Unit: Peat Rig Formation (PERG)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Grain Burn. 
Reference(s):
McMurtry, M J, 1980. The Ordovician rocks of the Bail Hill area, Sanquhar, south Scotland. Volcanism and sedimentation in the Iapetus Ocean. Unpublished PhD thesis (University of St. Andrews). 
Floyd, J D, 1996. Lithostratigraphy of the Ordovician rocks in the Southern Uplands: Crawford Group, Moffat Shale Group, Leadhills Supergroup. Transactions of the Royal Society of Edinburgh: Earth Sciences, Vol.86, 153-165. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S015