The BGS Lexicon of Named Rock Units — Result Details

Scremerston Formation

Computer Code: SCF Preferred Map Code: notEntered
Status Code: Full, pending ratification
Age range: Asbian Substage (CR) — Brigantian Substage (CX)
Lithological Description: The Scremerston Formation comprises alternations of sandstone, siltstone, mudstone and coal, with occasional thin dolomite or limestone beds. The sandstones are white, grey, brown or reddish brown, argillaceous and micaceous. They form beds with blocky or ratty gamma-log profiles that are typically less than 15 m thick, but one multistorey bed encountered in well 38/16-1 is 60 m thick. Sand grain size is mainly fine or medium in the wells 43/2-1 and 44/2-1, and in equivalent coal measures of Berwickshire (Smith 1967), but is relatively coarse in wells 36/13-1 and 38/16-1. The sandstones constitute about 50% of most sections but are less abundant in well 43/2-1. Interbedded siltstones and mudstones are grey or brownish grey and non-calcareous. Coal seams up to 1.5 m thick comprise less than 5% of most sections, but are thicker and more abundant in well 39/7-1. The limestones and dolomites are white, grey or yellowish brown, and are typically argillaceous and microcrystalline
Definition of Lower Boundary: In the two offshore wells to have penetrated the boundary between the Scremerston and Fell Sandstone formations, it is defined by an abrupt facies transition from argillaceous coal measures to massive sandstones. The boundary is marked by a sharp downward decrease in gamma-ray response and velocity in well 43/2-1. A thin coal seam occurs close above the facies transition in well 44/2-1. Onshore, the equivalent boundary is gradational, with mudstone and cementstone beds occurring for up to 60 m beneath the base of the coal-bearing strata (Smith 1967).
Definition of Upper Boundary: The top of the Scremerston Formation in wells 39/7-1 and 43/2-1 is defined by the base of the lowest high-velocity marine limestone bed of the Yoredale Formation. However, the transition to Yoredale facies is gradational, with prominent coal seams occurring for up to 64 m above the boundary in well 43/2-1. The Scremerston Formation is unconformably overlain by Lower Permian desert sediments or Upper Permian marine sediments and evaporites in all other North Sea sections.
Thickness: 100 m thick in well 43/2-1, but more than 266 m thick in well 38/16-1.
Geographical Limits: The Scremerston Formation may be continuous from the Northumberland coast across western crestal areas of the Mid North Sea High and along its southeastern flank to the median line. The formation is 100 m thick in well 43/2-1, but more than 266 m thick in well 38/16-1. Equivalent early Asbian coal measures are between 100 and 300 m thick in southeast Scotland and northeast England (Smith 1967; Leeder et al. 1989). These strata are thought to pass southwards into sand-prone facies onshore (Leeder et al. 1989), and are hence unlikely to continue to the southern margin of the Northumberland Trough either onshore or offshore. Well 39/7-1 proved an outlier of the Scremerston Formation on the northeastern flank of the Mid North Sea High. This outlier may be more extensive across the median line in adjacent Danish, German and Dutch waters than in the UK sector.
Parent Unit: Farne Group [Offshore] (FRNE)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Reference Section  North Sea well 38/16-1: 1933.5-2200 m TD (6343-7217ft TD) below KB. 
Reference Section  North Sea well 39/7-1: 3496-3614 m TD (11470-11856 ft TD). 
Reference Section  North Sea well 43/2-1: 2984-3083.5 m (9790-10116 ft). 
Reference Section  North Sea well 44/2-1: 2777.5-2862 m (9113-9390 ft). 
Reference(s):
Cameron, T D J. 1993. Carboniferous and Devonian of the Southern North Sea. In: Knox, R W O'B & Cordey, W G (eds.) Lithostratigraphic nomenclature of the UK North Sea. (British Geological Survey, Nottingham). 
Cameron, T D J, Crosby, A, Balson, P S, Jeffery, D H, Lott, G K, Bulat, J, and Harrison, D J. 1992. United Kingdom offshore regional report: the geology of the southern North Sea. (London: HMSO for the British Geological Survey.) 
Leeder, M R and Hardman, M. 1990. Carboniferous of the Southern North Sea Basin and controls on hydrocarbon prospectivity. In: Hardman, R F P and Brooks, J (eds.) Tectonic events responsible for Britain's oil and gas reserves. Geological Society, London, Special Publication No.55, 87-105. 
Leeder, M R, Fairhead, D, Lee, A, Stuart, G, Clemmey, H, El-Haddaheh, B and Green, C. 1989. Sedimentary and tectonic evolution of the Northumberland Basin. Proceedings of the Yorkshire Geological Society 47, 207-223. 
Smith, T E. 1967. A preliminary study of sandstone sedimentation in the Lower Carboniferous of the Tweed Basin. Scottish Journal of Geology 3, 282-305. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable