The BGS Lexicon of Named Rock Units — Result Details

Dunnottar Group [Obsolete Name And Code: See Dunnottar-Crawton Group]

Computer Code: DRG Preferred Map Code: DTR
Status Code: Index Level
Age range: Silurian Period (S) — Early Devonian Epoch (DL)
Lithological Description: Conglomerate, clast-supported, with well-rounded boulders, cobbles and pebbles predominantly of lava, psammite and quartzite. Lenses and thicker formations of lithic and volcaniclastic sandstone. Trachybasalt and trachyandesite lavas are interbedded with conglomerate.
Definition of Lower Boundary: Base of Downie Point Conglomerate Member, where thickly-bedded or massive conglomerate overlies pebbly sandstone of Carron Sandstone Formation with apparent conformity. This marks the base of a thick, conglomerate-dominated succession.
Definition of Upper Boundary: Not seen, presumed to pass up conformably into conglomerate of Crawton Group.
Thickness: Variable, maximum of 2600m, thinning westwards to less than 1500m. Presumed to be overlapped by younger groups to south-west.
Geographical Limits: North-eastern Midland Valley, Stonehaven area.
Parent Unit: Not Entered (?)
Previous Name(s): Dunnottar Conglomerate (-871)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Sea cliffs and foreshore, Downie Point to Mons Craig. [See also stratotypes of component (Downie Point Conglomerate; Strathlethan; Dunnottar Castle Conglomerate and Tremuda Bay Volcanic) formations.] 
Reference(s):
Campbell, R, 1913. The geology of south-eastern Kincardineshire. Transactions of the Royal Society of Edinburgh, Vol.48, pp.923-960. 
Carroll, S, 1994. Geology of the Stonehaven District. 1:10 000 Sheets NO88NW, NO88NE, NO88SW and NO88SE. British Geological Survey Technical Report WA/94/19. 
Haughton, P D W, 1989. Structure of some Lower Old Red Sandstone conglomerates, Kincardineshire, Scotland: deposition from late-orogenic antecedent streams? Journal of the Geological Society, Vol.146, 509-525. 
Armstrong, M and Paterson, I B, 1970. The Lower Old Red Sandstone of the Strathmore Region. Report of the Institute of Geological Sciences No.70/12 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
S067 S066