The BGS Lexicon of Named Rock Units — Result Details

Swanshaw Sandstone Formation

Computer Code: SWAS Preferred Map Code: SWAS
Status Code: Full
Age range: Ludlow Epoch (SU) — Early Devonian Epoch (DL)
Lithological Description: Red-brown, grey-green and chocolate-brown, medium and coarse-grained terrestrial sandstones with subordinate pebble beds and conglomerates, minor fine-grained sandstones, siltstones and mudstones.
Definition of Lower Boundary: The top of the Greywacke Conglomerate, which is a massive coarse conglomerate over 25 m thick comprising mainly greywacke pebbles.
Definition of Upper Boundary: The base of an andesite volcanic sequence, such as the Duneaton Volcanic Formation around New Cunnock, within the Lower Old Red Sandstone.
Thickness: Estimated to be at least 750 m thick.
Geographical Limits: Between the Ayrshire and Douglas Carboniferous basins, continuing north-east into the Pentland Hills in Ayrshire and Lanarkshire, Scotland.
Parent Unit: Lanark Group (LNK)
Previous Name(s): Swanshaw Formation (-1212)
Lanark Sandstone Formation [Obsolete Name And Code: See SWAS] (LKSF)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Along Swanshaw Burn and Duneaton Water, the base is located in the headwaters of the Swanshaw Burn 760m north, 60 degrees east of Cairn Table Summit, and the top is located at Duneaton Water, 160m west of the entry of Black Burn. 
Reference(s):
Browne, M A E, Smith, R A and Aitken, A M. 2001. A lithostratigraphical framework for the Devonian (Old Red Sandstone) rocks of Scotland south of a line from Fort William to Aberdeen. Version 3. British Geological Survey Research Report RR/01/04. 
Smith, R A. 1999. Geology of the New Cumnock district - a brief explanation of the geological map. Sheet Explanation of the British Geological Survey. 1:50 00 sheet 15W, New Cumnock (Scotland). 
Smith, R A. 1994. Geological notes and local details for 1:10 000 sheet, NS72SW. British Geological Survey Technical Report, WA/94/9. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S008 S015 S023 S007 S008 S015 S023 S024 S032 S014 S014 S022