The BGS Lexicon of Named Rock Units — Result Details

Drummuck Subgroup

Computer Code: DKG Preferred Map Code: DKG
Status Code: Full
Age range: Ashgill Series (OA) — Ashgill Series (OA)
Lithological Description: Consists mainly of mudstones, some olive-green in colour, with sandy beds and basal conglomerate or grit.
Definition of Lower Boundary: Drawn at base of basal conglomerate of the Auldthorns Formation where this rests conformably on alternating shales and sandstone of the Shalloch Formation.
Definition of Upper Boundary: Drawn at unconformity at base of Silurian Mulloch Hill Conglomerate.
Thickness: c.380m
Geographical Limits: Confined to Craighead Inlier, Ayrshire, Scotland.
Parent Unit: Ardmillan Group (AMN)
Previous Name(s): Trilobite Shale (-2755)
Drummock Group (-863)
Drummock Beds (-4609)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Drummuck Farm, northeast of Girvan, Ayrshire, Scotland. 
Reference(s):
Greig, D C. 1971. British Regional Geology: the South of Scotland (3rd Edition). (Edinburgh: HMSO for the Institute of Geological Sciences.) 
Lapworth, C, 1882. The Girvan Succession. Quarterly Journal of the Geological Society of London, Vol. 38, 537-666. 
Lamont, A. 1935. The Drummuck Group, Girvan; A stratigraphical revision, with descriptions of new fossils from the lower part of the group. Transactions of the Geological Society of Glasgow, Vol.19, 288-334. 
Walton, E K. 1983. Lower Palaeozoic - Stratigraphy. In Craig, G Y (editor), Geology of Scotland (2nd edition)(Edinburgh: Scottish Academic Press.) 
Murchison, R I. 1851. On the Silurian rocks of the south of Scotland. Quarterly Journal of the Geological Society of London, Vol.7, p.137. 
Harper, D A T, 1982. The stratigraphy of the Drummock Group (Ashgill), Girvan. Geological Journal, Vol.17, p.251-277.l. 17 251-277 
Fortey, R A, Harper, D A T, Ingham, J K, Owen, A W, Parkes, M A, Rushton, A W A and Woodcock, N H. 2000. A revised correlation of Ordovician rocks in the British Isles. Geological Society Special Report, No.24. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S014