The BGS Lexicon of Named Rock Units — Result Details

Rad Brook Mudstone Member

Computer Code: RKM Preferred Map Code: RkM
Status Code: Full
Age range: Holkerian Substage (CQ) — Holkerian Substage (CQ)
Lithological Description: A dark to pale olive-and blue-grey, calcareous, bioturbated mudstone, interbedded with dark, laminated, micromicaceous, calcareous siltstones andsporadic fine-grained, grey-blue packstones and wackestones.
Definition of Lower Boundary: The base of the first mudstone above the characteristic pale noduliferous wackestones of the Hodderense Limestone Formation.
Definition of Upper Boundary: Taken at the base of the lowest packstone of the Pendleside Limestone Formation with less than 50% interbedded mudstone.
Thickness: Up to 100 m thick.
Geographical Limits: Limited to the southern part of the Craven Basin; absent north of the Clitheroe (SD82 44) and Whitwell (SD64 47) anticlines.
Parent Unit: Pendleside Limestone Formation (PDL)
Previous Name(s): Rad Brook Beds (-4864)
Alternative Name(s): none recorded or not applicable
Type Section  Pendle Hill, stream section in Rad Brook, 2 km east of Worston: Complete section is exposed. Riley, 1990. 
Riley N J. 1990. Stratigraphy of the Worston Shale Group (Dinantian) Craven Basin, north-west England. Proceedings of the Yorkshire Geological Society, Vol. 48, 163-187. 
Metcalfe, I, 1981. Conodont zonation and correlation of the Dinantian and early Namurian strata of the Craven Lowlands of Northern England. Institute of Geological Sciences, Report No. 80/10, p.1-70. 
Aitkenhead, N, Bridge, D M, Riley, N J and Kimbell, S F. 1992. Geology of the country around Garstang. Memoir of the British Geological Survey, Sheet 67 (England and Wales) 
1:50K maps on which the lithostratigraphical unit is found, and map code used: