The BGS Lexicon of Named Rock Units — Result Details

Hambleton Mudstone Member

Computer Code: HAM Preferred Map Code: notEntered
Status Code: Full
Age range: Anisian Age (TA) — Anisian Age (TA)
Lithological Description: Mudstone, grey, interlaminated with siltstone, pale grey, micaceous.
Definition of Lower Boundary: Conformable, at the rapidly gradational upward transition from the pale brown or pinkish red sandstones of the Ormskirk Sandstone Formation (Sherwood Sandstone Group) to the grey, laminated mudstones and micaceous siltstones of the Hambleton Mudstone Member.
Definition of Upper Boundary: Conformable, within a gradational upward transition from grey, laminated mudstones and micaceous siltstones of the Hambleton Mudstone Member to laminated reddish brown and greenish grey mudstones (Sidmouth Mudstone Formation, undifferentiated).
Thickness: 30m to 37m (Wilson and Evans, 1990)
Geographical Limits: North Fylde peninsula, Lancashire.
Parent Unit: Sidmouth Mudstone Formation (SIM)
Previous Name(s): Hambleton Mudstones (-3454)
Hambleton Mudstone Formation (-4694)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Hambleton Borehole (SD34SE/5), Fylde, Lancashire, full sequence proved between 102.59m and 135.76m depth. Curated core held at the National Geosciences Records Centre, BGS Keyworth. Wilson and Evans (1990) 
Reference(s):
Howard, A S, Warrington, G, Ambrose, K, and Rees, J G. 2008. A formational framework for the Mercia Mudstone Group (Triassic) of England and Wales. British Geological Survey Research Report, RR/08/04. 
Wilson, A A and Evans, W B. 1990 Geology of the country around Blackpool. Memoir of the British Geological Survey, Sheet 66. (England and Wales). 
Jackson, D I, Johnson, H and Smith, N J P. 1997. Stratigraphical relationships and a revised lithostratigraphical nomenclature for the Carboniferous, Permian and Triassic rocks of the offshore East Irish Sea Basin. 11-32 in Petroleum Geology of the Irish Sea and Adjacent Areas. Meadows, N S, Trueblood, S P, Hardman, M and Cowan, G. (editors). Geological Society Special Publication, No.124. 
Wilson, A A. 1990. The Mercia Mudstone Group (Trias) of the East Irish Sea Basin. Proceedings of the Yorkshire Geological Society, Vol.48, 1-22. 
Warrington, G, Audley-Charles, M G, Elliott, R E, Evans, W B, Ivimey-Cook, H C, Kent, P E, Robinson, P L, Shotton, F W and Taylor, F M. 1980. A correlation of the Triassic rocks in the British Isles. Special Report of the Geological Society of London, No.13. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E075 E066 E067 E058 E048