The BGS Lexicon of Named Rock Units — Result Details

Montrose Group

Computer Code: MONT Preferred Map Code: notEntered
Status Code: Full
Age range: Paleocene Epoch (GP) — Paleocene Epoch (GP)
Lithological Description: The Montrose Group is characterized by mudstones that are variable in character but that differ from those of the overlying Moray Group in containing an abundant microfauna and in being poorly bedded, non-pyritic and mostly non-carbonaceous. In its type area it comprises the Lista Formation and the Maureen Formation, of which only the Lista Formation extends into the more southerly parts of the Southern North Sea. The mudstones of the Maureen Formation display a downward increase in the proportion of carbonate, culminating in chalky marls that grade downwards into the chalky limestones of the Ekofisk Formation. The sandstones of the Montrose Group were deposited as submarine fans (Parker 1975; Knox et al., 1981; Rochow 1981; Mudge and Bliss 1983; Stewart 1987).
Definition of Lower Boundary: The base of the Maureen Formation is taken at the upward change from chalky limestone or marl of the Chalk Group or Shetland Group to a more variable succession of thinly interbedded marl and limestone with local sandstone.
Definition of Upper Boundary: The upper boundary is marked by a downward change from grey to grey-brown, carbonaceous, pyritic, mudstones and siltstones of the Moray Group to greenish, non-pyritic mudstones with abundant microfauna of the Montrose Group.
Thickness: The Montrose Group reaches over 600 m in parts of the Outer Moray Firth.
Geographical Limits: The Montrose Group extends throughout the North Sea area (Knox and Holloway 1992; Lott and Knox 1994). It also includes partial lateral equivalents onshore (Aldiss, 2014).
Parent Unit: Not Applicable (-)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
none recorded or not applicable
Reference(s):
Waters, C N, Smith, K, Hopson, P M, Wilson, D, Bridge, D M, Carney, J N, Cooper, A H, Crofts, R G, Ellison, R A, Mathers, S J, Moorlock, B S P, Scrivener, R C, McMillan, A A, Ambrose, K, Barclay, W J, and Barron, A J M. 2007. Stratigraphical Chart of the United Kingdom: Southern Britain. British Geological Survey, 1 poster. 
Waters, C N, Gillespie, M R, Smith, K, Auton, C A, Floyd, J D, Leslie, A G, Millward, D, Mitchell, W I, McMillan, A A, Stone, P, Barron, A J M, Dean, M T, Hopson, P M, Krabbendam, M, Browne, M A E, Stephenson, D, Akhurst, M C, and Barnes, R P. 2007. Stratigraphical Chart of the United Kingdom: Northern Britain. (British Geological Survey.) 
Parker, J R. 1975. Lower Tertiary sand development in the Central North Sea. In: Woodland, A W (ed.) Petroleum and the continental shelf of northwest Europe, 447-453. Applied Science Publishers, London. 
Rochow, K. 1981. Seismic stratigraphy of the North Sea 'Palaeocene' deposits. In: Illing, L V and Hobson, G D (eds) Petroleum geology of the continental shelf of North-West Europe, 255-266. Heyden and Son, London. 
Lott, G K and Knox, R W O'B. 1994. 7. Post-Triassic of the Southern North Sea. In: Knox, R W O'B and Cordey, W G (eds.) Lithostratigraphic nomenclature of the UK North Sea. British Geological Survey, Nottingham. 
Knox, R W O'B and Holloway, S. 1992. 1. Paleogene of the Central and Northern North Sea. In: Knox, R W O'B and Cordey, W G (eds.) Lithostratigraphic nomenclature of the UK North Sea. British Geological Survey, Nottingham. 
Aldiss, D T. 2014. The stratigraphical framework for the Palaeogene successions of the London Basin, UK. British Geological Survey Open Report, OR/14/008. 95pp. 
Deegan, C E and Scull, B J. 1977. A standard lithostratigraphic nomenclature for the Central and Northern North Sea. Report of the Institute of Geological Sciences, 77/25; NPD Bulletin No.1. 
King, C. in prep. A revised correlation of Palaeogene and Neogene deposits in the British Isles. Geological Society of London Special Report. 
Knox, R W O B. 1984. Lithostratigraphy and depositional history of the late Toarcian sequence at Ravenscar, Yorkshire. Proceedings of the Yorkshire Geological Society, Vol. 45, 99-108. 
Stewart, I J. 1987. A revised stratigraphic interpretation of the Early Palaeogene of the Early Palaeogene of the central North Sea. In: Brooks, J and Glennie, K W (eds.) Petroleum geology of North West Europe, 557-576.Graham & Trotman, London. 
Knox, R W O'B, Morton, A C, and Harland, R. 1981. Stratigraphical relationships of Palaeocene sands in the UK sector of the Central North Sea. In: Illing, L V and Hobson, G D (eds) Petroleum geology of the continental shelf of North-West Europe, 267-281. Heyden, London. 
Mudge, D C, and Bliss, G M. 1983. Stratigraphy and sedimentation of the Palaeocene sands in the northern North Sea. In: Brooks, J (ed.) Petroleum geochemistry and exploration of Europe. Geological Society, London, Special Publication No. 12, 95-111. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable