The BGS Lexicon of Named Rock Units — Result Details

Grassington Grit

Computer Code: GGF Preferred Map Code: GG
Status Code: Index Level
Age range: Pendleian Substage (CE) — Pendleian Substage (CE)
Lithological Description: A medium- to thickly-bedded, brownish grey, medium- to coarse-grained sandstone and pebbly sandstone, which is massive to coarse bedded; beds of siltstone can occur throughout and locally coals are developed. The unit is interpreted as a delta top sandstone.
Definition of Lower Boundary: A sharp upward change in a conformable succession from the predominantly grey mudstone to sandstone-base of first pebbly sandstone bed above the Pendle Grit Member.
Definition of Upper Boundary: A sharp upward change in a conformable succession from sandstone to predominantly mudstone - top of the last coarse-grained or pebbly sandstone below the synsedimentary slumped siltstones and sandstones of the Roeburndale Member.
Thickness: From 75 to 100m
Geographical Limits: The Yorkshire Pennines to the east of the River Ribble.
Parent Unit: Pendleton Formation (PENDL)
Previous Name(s): Grassington Grit Formation (-1558)
Alternative Name(s): Brennand Grit
Bearing Grit
Warley Wise Grit
Partial Type Section  Far Costy Clough, a headwater stream of the River Hodder, near Slaidburn, Lancashire; base not seen. Arthurton and others, 1988. 
Dakyns, J R. 1892. The geology of the country between Grassington and Wensleydale. Proceedings of the Yorkshire Geological Society. Vol.12, 133-144. 
Arthurton, R S, Johnson, E W and Mundy, D J C. 1988. Geology of the country around Settle. Memoir of the British Geological Survey, Sheet 60 (England and Wales). 
Moseley, F, 1956. The geology of the Keasden area, west of Settle, Yorkshire. Proceedings of the Yorkshire Geological Society, Vol.30, 331-352. 
Dunham, K C and Stubblefield, C J. 1944. The stratigraphy, structure and mineralization of the Greenhow mining area, Yorkshire. Proceedings of the Yorkshire Geological Society, Vol.100, 209-268. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E051 E060