The BGS Lexicon of Named Rock Units — Result Details

Townhead Boulder Gravel Member

Computer Code: THBG Preferred Map Code: notEntered
Status Code: Full
Age range: Devensian Stage (QD) — Devensian Stage (QD)
Lithological Description: Clast-supported, very poorly sorted boulder gravel, with clasts up to >2.5m in diameter. Clasts are generally angular to subrounded and mainly comprise red Permian sandstone, yellow and white Coal Measure sandstones, black Coal Measure mudstone, together with some coal, green Borrowdale Volcanic Group lavas, grey Criffel granite, ironstone, greywacke and limestone.
Definition of Lower Boundary: Steep erosional (channelled) base against well bedded units of the St Bees Sand and Gravel Member of the Seascale Glacigenic Formation.
Definition of Upper Boundary: Planar unconformable base of the How Man Till Member of the Gosforth Glacigenic Formation.
Thickness: c.10m
Geographical Limits: Nethertown area of 1:50k Sheet 28 (Whitehaven) only.
Parent Unit: Seascale Glacigenic Formation (SEAG)
Previous Name(s): Middle Sands And Gravels (-122)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Sea cliff section (Log NX90ME7 - Nirex Science Report 768), 175m northwest of beach car park at Nethertown, c.600m northeast of Nethertown, west Cumbria. Nirex Science Report SA/97/045 (Issue 2.0) 1997. 
Reference(s):
Merritt, J W and Auton, C A. 1997. Quaternary lithostratigraphy of the Sellafield district. Nirex Science Report SA/97/045 (Issue 2.0). [Report prepared for UK Nirex Ltd. 69pp, 5 tables, 20 figures, 14 enclosures and one appendix.] 
Merritt, J W, Auton, C A, Browne, M A E, Neilson, G and McMillan, A A. 1995. Characterisation of the onshore Quaternary deposits around Sellafield, Cumbria, Phase II. Nirex Science Report 768. 
Eastwood T, and others. 1968. Geology of the country around Whitehaven. Memoir of the Geological Survey of Great Britain, Sheet 28 (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
none recorded or not applicable