The BGS Lexicon of Named Rock Units — Result Details

Woodhouselee And Braid Hills Group [Obsolete Name And Code: Use WDH]

Computer Code: WBG Preferred Map Code: notEntered
Status Code: Index Level
Age range: Early Devonian Epoch (DL) — Early Devonian Epoch (DL)
Lithological Description: Pale lilac or pink trachytes and andesites with phenocrysts of biotite and alkali-feldspars, principally sanidine in a fluidal matrix or laths of sanidine with patches of haematite and secondary grains of quartz.
Definition of Lower Boundary: Drawn at the base of trachytes, acid andesites and other silicified acid rocks of the Woodhouselee Group where it conformably rests upon rhyolites, acid tuffs, trachyte and andesite of the Caerketton Group.
Definition of Upper Boundary: Drawn at the conformable upward passage of the Woodhouselee Group from trachytes, andesites and silicified acid rocks to basalts and basic andesite of the Carwethy and Hill End Group.
Thickness: Maximum thickness 250 metres approximately.
Geographical Limits: Midland Valley of Scotland.
Parent Unit: Not Entered (?)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Type Area  The Pentland Hills, approximately 2kms from Swanston, Edinburgh. 
Cameron, I B and Stephenson, D, 1985. British Regional Geology: The Midland Valley of Scotland (3rd Edition). (London: HMSO for British Geological Survey). 
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. 
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:
none recorded or not applicable