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):
Harper, D A T, 1982. The stratigraphy of the Drummock Group (Ashgill), Girvan. Geological Journal, Vol.17, p.251-277.l. 17 251-277 
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.) 
Greig, D C. 1971. British Regional Geology: the South of Scotland (3rd Edition). (Edinburgh: HMSO for the Institute of Geological Sciences.) 
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. 
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. 
Lapworth, C, 1882. The Girvan Succession. Quarterly Journal of the Geological Society of London, Vol. 38, 537-666. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S014