The BGS Lexicon of Named Rock Units — Result Details

Warklaw Hill Volcanic Member

Computer Code: WKH Preferred Map Code: WKH
Status Code: Full
Age range: Pridoli Epoch (SO) — Lochkovian Age (DO)
Lithological Description: This formation is composed of four well-defined subdivision as follows in downward sequence: d) Several thin flows of macroporphyritic olivine-basalts with large feldspar phenocrysts up to 5mm long; c) Several flows of macroporphyritic olivine-basalt with large phenocrysts of olivine and feldspar; b) Several thick flows (to 27m) of microporphyritic olivine-basalt with fluxion texture. a) Thin flows of porphyritic olivine-basalt.
Definition of Lower Boundary: Not exposed: lowest flows faulted against Inverclyde Group sediments.
Definition of Upper Boundary: Not seen: highest flows seen are highly vesicular purplish-grey feldspar-phyric basalts, 3.0-3-7m thick.
Thickness: At least 175m
Geographical Limits: Pentland Hills.
Parent Unit: Pentland Hills Volcanic Formation (PDH)
Previous Name(s): Bonaly Group [Obsolete Name And Code: Use BNY] (BOG)
Warklaw Hill Volcanic Formation [Obsolete Name and Code: Use WKH] (-3129)
Bed B [Obsolete Name and Code: Use CKRI, WKH] (-3935)
Warklaw Hill Group [Obsolete Name and Code: Use WKH] (-4978)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Partial Type Section  Torphin Quarry, quarry face, flows of sub-division b) and c). 
Partial Type Section  Kinleith Burn, 40m upstream from hotel to 180m upstream from bridge at Easter Kinleath. Flows of subdivision a) and b) 
Reference(s):
Mykura, W, 1960. The Lower Old Red Sandstone igneous rocks of the Pentland Hills. Bulletin of the Geological Survey of Great Britain, No.16, 131-155. 
Howell, H H and Geikie, A, 1861. The Geology of the neighbourhood of Edinburgh (1st edition). Memoir of the Geological Survey, Scotland. 
Mykura, W, 1986. Pentland Hills. 161-173 in Lothian Geology. An Excursion Guide. McAdam, A D and Clarkson, E N K (editors). (Edinburgh: Scottish Academic Press.) 
Peach, B N, Clough, C T, Hinxman, L W, Grant Wilson, J S, Crampton, C B, Maufe, H B and Bailey, E B, 1910. The geology of the Neighbourhood of Edinburgh (2nd edition). Memoir of the Geological Survey of Scotland, Sheet 32 (Scotland). 
Geikie, A, 1897. The Ancient Volcanoes of Great Britain. Vol.1, 317-325. (London: Macmillan). 
Thirlwall, M F, 1988. Geochronology of Late Caledenian magmatism in northern Britain. Journal of the Geological Society, Vol.145, 951-967. 
Cameron, I B and Stephenson, D, 1985. British Regional Geology: The Midland Valley of Scotland (3rd Edition). (London: HMSO for British Geological Survey). 
Mitchell, G H. 1962. The geology of the neighbourhood of Edinburgh. (Explanation of Sheet 32) Third Edition. (Reprinted 1980). Memoir of the Geological Survey of Great Britain (Scotland). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S032 S032