The BGS Lexicon of Named Rock Units — Result Details
Low Water Tuff Formation
| Computer Code: | LWW | Preferred Map Code: | LwW |
|---|---|---|---|
| Status Code: | Full | ||
| Age range: | Caradoc Series (O4) — Caradoc Series (O4) | ||
| Lithological Description: | Welded dacitic lapilli tuffs with subordinate interbedded volcaniclastic sandstone and tuff. | ||
| Definition of Lower Boundary: | Formation unconformably overlies the Paddy End Tuff Member of the Lickle Tuff Formation for most of its outcrop; at the southern end it overlies the Lag Bank Tuff Formation. The base is defined at the lowest extent of homogneous, fine, lapilli-tuff of dacite composition or, where present, the base of the underlying volcaniclastic sandstones. | ||
| Definition of Upper Boundary: | Overlain by Seathwaite Fell Sandstone Formation; abrupt change to volcaniclastic sandstone. | ||
| Thickness: | To c.400m | ||
| Geographical Limits: | Low Water (SD 275 982) to Greenburn Beck (NY 310 030), Coniston Fells, Lingmoor Fell (NY 300 035), Cumbria. | ||
| Parent Unit: | Borrowdale Volcanic Group (BVG) | ||
| Previous Name(s): | Lingmoor Fell Formation [Obsolete Name: Part Of LWW]
(LRF)
Low Water Formation [Obsolete Name and Code: Use LWW] (-1675) |
||
| Alternative Name(s): | none recorded or not applicable | ||
| Stratotypes: | |||
| Type Area | Lad Stones, above Beck Fells, Coniston, Cumbria. | ||
| Reference(s): | |||
| Millward, D. 2004. A stratigraphical framework for the Upper Ordovician and Lower Devonian volcanic and intrusive rocks in the English Lake District and adjacent areas. British Geological Survey, Research Report: RR/01/007. | |||
| Millward, D, Johnson, E W, Beddoe-Stephens, B, Young, B, Kneller, B C, Lee, M K, Fortey, N J, Allen, P M, Branney, M J, Cooper, D C, Hirons, S, Kokelaar, B P, Marks, R J, McConnell, B J, Merritt, J W, Molyneux, S G, Petterson, M G, Roberts, B, Rundle, C C, Rushton, A W A, Scott, R W, Soper, N J, and Stone, P. 2000. Geology of the Ambleside district. Memoir of the British Geological Survey, England and Wales, Sheet 38. | |||
| Mitchell, G H, 1940. The Borrowdale Volcanic Series of Coniston, Lancashire. Quarterly Journal of the Geological Society of London, Vol.96, p.301-319. | |||
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: | |||
| E038 | |||