The BGS Lexicon of Named Rock Units — Result Details

Tay Sandstone Member

Computer Code: TAYS Preferred Map Code: notEntered
Status Code: Full, pending ratification
Age range: Early Eocene Epoch (GEE) — Mid Eocene Epoch (GEM)
Lithological Description: Thinly or thickly bedded, clean to argillaceous, fine to medium grained sandstones, interbedded with variably silty, fissile, green-grey to grey mudstones and siltstones. Thin turbidite sandstones occur within the mudstone units.
Definition of Lower Boundary: The base of the Tay Sandstone Member normally rests conformably on a thin unit of Horda mudstone. However, over salt-induced highs in the south of Quadrant 21 it locally rests disconformably on Balder Formation, Sele Formation (e.g. 21/25-6), or Lista Formation (e.g. 21/22-1).
Definition of Upper Boundary: The top of the Tay Sandstone Member is defined by a downward change from green-grey mudstone to relatively clean sandstone. This is associated with a decrease in gamma-ray values and generally by an increase in velocity (but see 21/25-6).
Thickness: none recorded or not applicable
Geographical Limits: The Tay Sandstone Member is restricted to southern parts of Quadrants 21 and 22. The sandstones show a complex distribution due, in part, to the effects of salt movement during sedimentation (Armstrong et al. 1987).
Parent Unit: Horda Formation (HORD)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Type Section  North Sea well 21/18-1A: 1687.5-1945 m (5536-6382 ft) below KB (Knox and Holloway, 1992). 
Reference Section  North Sea well 21/25-6: 2057-2145 m (6748-7037 ft) (Knox and Holloway, 1992). 
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. 
Armstrong, L A, Ten Have, A, and Johnson, H D. 1987. The geology of the Gannet Fields, Central North Sea. In Brooks, J and Glennie, K W (eds.) Petroleum geology of North West Europe, 533-548 [Graham and Trotman, London]. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable