The BGS Lexicon of Named Rock Units — Result Details

Knott Hill Formation (Metasomatically Altered) [Obsolete Usage: Use KHSA]

Computer Code: KHSAM Preferred Map Code: KHSa'
Status Code: Index Level
Age range: Arenig Series (OR) — Arenig Series (OR)
Lithological Description: Thin-bedded and laminated sandstone, interpreted as distal turbidites.
Definition of Lower Boundary: A gradational transition from undivisional Skiddaw Group silty mudstone, over 10 - 20m through laminated sandy siltstone into sandstone.
Definition of Upper Boundary: The top is unconformable with the overlying Borrowdale Volcanic Group.
Thickness: About 250 m (+/-50m) thick.
Geographical Limits: Within 1 km of the summit of Knott Hill.
Parent Unit: Skiddaw Group (SKG)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Type Area  Summit area of Knott Hill, above the 200 m contour. 900 m north west of Broadgate, near Hallwaites, Cumbria. Johnson, Soper & Burgess, 2001. 
Johnson, E W, Soper, N J, Burgess, I C, Ball, D F, Beddoe-Stephens, B, Carruthers, R M, Fortey, N J, Hirons, S, Merritt, J W, Millward, D, Roberts, B, Walker, A B and Young, B. 2001. Geology of the country around Ulverston. Memoir of the British Geological Survey, England and Wales, Sheet 48. 
British Geological Survey, 1994(a). Duddon Bridge and Hallthwaites, SD18NE, Solid and Drift 1:10,000. (Keyworth, Nottingham, British Geological Survey). 
1:50K maps on which the lithostratigraphical unit is found, and map code used: