The BGS Lexicon of Named Rock Units — Result Details

Poltallan Member

Computer Code: POLT Preferred Map Code: POLT
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Breccia of amygdaloidal lava clasts in a clastic or tuffaceous matrix with intercalations of dark silty mudstone.
Definition of Lower Boundary: Appearance of lava clasts in sandstone-siltstone succession.
Definition of Upper Boundary: Last occurrence of lava clasts.
Thickness: c.40m
Geographical Limits: none recorded or not applicable
Parent Unit: Kirkcolm Formation (KKF)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Type Section  In Poltallan Burn near bend in wall c.300m upstream of junction of Poltallan Burn with Euchan Water. 
Peach, B N and Horne, J. 1899. The Silurian Rocks of Britain, Volume 1. Scotland. Memoir of the Geological Survey of the United Kingdom. 
Floyd, J D, 1982. Stratigraphy of a flysch succession: The Ordovician of West Nithsdale, South West Scotland. Transactions of the Royal Society of Edinburgh, Earth Sciences, Vol.73 (1), p.1-9. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S015 S015