The BGS Lexicon of Named Rock Units — Result Details

Beith Lava Member

Computer Code: BELA Preferred Map Code: notEntered
Status Code: Full
Age range: Arundian Substage (CJ) — Asbian Substage (CR)
Lithological Description: Olivine-microphyric basalts (Dalmeny type). Red boles are common between flows and interbedded chocolate-coloured marls are present. Large parts of the flows are extensively altered and decomposed. South of Roebank Glen [2353 6554] a flow of plagioclase-macrophyric basalt (Markle type) outcrops within the member.
Definition of Lower Boundary: Underlain by the Markle- and Dunsapie-type basalts of the Fereneze Lava Member.
Definition of Upper Boundary: Overlain by volcaniclastic sedimentary rocks of the Kirkwood Formation wherever the top of the member crops out.
Thickness: About 90 m.
Geographical Limits: The unit occurs to the west and south-west of the Beith-Barhead Hills. The unit underlies the town of Beith [NS 35 54] and extends north east to just north of East Gavin [NS 389 599].
Parent Unit: Clyde Plateau Volcanic Formation (CPV)
Previous Name(s): Beith Lavas (-3840)
Alternative Name(s): none recorded or not applicable
Reference Section  Crummock Park borehole penetrated the lowest 50 m of the Beith Lava Member, Monro 1999. A detailed geological log (NS35SE/1) is available in BGS borehole records. 
Type Area  The Beith Lava Member crops out on lower slopes at the south-western limit of the Beith-Barrhead Hills, Monro 1999. 
Monro, S K. 1999. Geology of the Irvine District. Memoir of the British Geological Survey, Sheet 22W and part of 21E (Scotland). 
Paterson, I B, Hall, I H S and Stephenson, D. 1990. Geology of the Greenock district: Memoir for 1:50000 geological sheet 30W and part of sheet 29E (Scotland). 
Richey, J E, Anderson, E M, and Macgregor, A G. 1930.The geology of north Ayreshire. Memoir of the Geological Survey of Great Britain. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S022 S030