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). 
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. 
Moseley, F, 1956. The geology of the Keasden area, west of Settle, Yorkshire. Proceedings of the Yorkshire Geological Society, Vol.30, 331-352. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E051 E060