The BGS Lexicon of Named Rock Units — Result Details

Pennine Coal Measures Group

Computer Code: PCM Preferred Map Code: PCM
Status Code: Full
Age range: Langsettian Substage (CA) — Asturian Substage (CAS)
Lithological Description: Alternation of sandstone, grey siltstone and grey mudstone, with frequent coal seams and seatearth horizons. Note that, definitions for the base of the Pennine Coal Measures Group and the bases of the Middle and Upper Formations are those of Stubblefield and Trotter (1957), but the top of the Pennine Coal Measures Group is newly defined here on a purely lithostratigraphical basis.
Definition of Lower Boundary: The base of the mudstone of the Gastrioceras subcrenatum Marine Band (=Subcrenatum Marine Band) or at the base of the lowest coal within the coal-bearing sequence if this marker band cannot be identified.
Definition of Upper Boundary: Taken at the base of the lowest conformably overlying red-bed formation, - Etruria Marl or lateral equivalent of the Warwickshire Group in North Wales and Central England, or the Whitehaven Sandstone Formation in West Cumbria, and elsewhere taken at the sub-Permian unconformity.
Thickness: Up to 1600m thick in the Potteries Syncline of Stoke, 900m thick in the Northumberland-Durham Coalfield, 300-400m thick in West Cumbria, 100-200m thick in the South Staffordshire-Warwickshire Coalfield.
Geographical Limits: Central and Northern England and North Wales.
Parent Unit: Coal Measures Supergroup (COME)
Previous Name(s): Bettisfield Formation [Obsolete Name And Code: Within PCM] (BTD)
Coal Measures Group (CM)
Productive Coal Measures [Obsolete Name And Code: Use LMC] (LMCM)
Alternative Name(s): none recorded or not applicable
Reference Section  Boundary between Lower and Middle Coal Measures: Miry Wood, Apedale, Stoke-on-Trent, listed as 'Locality C' on map SJ84NW (Silverdale) 1991, with the base of the Vanderbeckei Marine Band as the boundary. Intended to become a designated RIGS site. 
Reference Section  Upper part and top: Wolstanton Colliery no.3 Shaft Stoke-on-Trent (SJ84NE/29), from 1142 ft 7 ins (348.2m) to the base of shaft. 
Reference Section  Base and lower part: Ridgeway Borehole, Stoke-on-Trent (SJ85SE/14) from 1806 ft 10 ins (550.7m) depth to the surface. 
Reference Section  Middle and Upper Coal Measures: Parkhouse Colliery No.1 Underground Borehole, Stoke-on-Trent (SJ85SW/19), where the top of the Cambriense Marine Band, at 529 ft (161.2m) depth in the bore, marks the boundary. 
Type Area  Potteries Syncline, Stoke-on-Trent, North Staffordshire numerous borehole and shaft sections but few good exposures. 
Waters, C N, Waters, R A, Barclay, W J, and Davies, J R. 2009. Lithostratigraphical framework for Carboniferous successions of Southern Great Britain (Onshore). British Geological Survey Research Report, RR/09/01. 184pp. 
Waters, C N, Barclay, W J, Davies, J R and Waters, R A. In press. Stratigraphical framework for Carboniferous successions of Southern Great Britain (Onshore). British Geological Survey Research Report, RR/05/06. 
Besley B M, 1988. Palaeogeographic implications of late Westphalian to early Permian red-beds, central England. "In" Sedimentation in a synorogenic basin complex. Besley B M and Kelling, G, editors. 
Whitehead, T H and Pocock, R W. 1947. Geology of the country around Dudley and Bridgnorth. Memoir of the British Geological Survey, Sheet 167. (England and Wales). 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E009 E010 E011 E012 E014 E015 E018 E019 E020 E021 E022 E023 E026 E027 E028 E031 E032 E049 E050 E051 E052 E059 E060 E062 E068 E069 E070 E075 E076 E077 E078 E084 E085 E086 E087 E097 E098 E099 E100 E105 E107 E108 E110 E111 E112 E121 E123 E124 E125 E126 E137 E139 E141 E152 E153 E154 E155 E166 E167 E168 E169 E181 E182 E024