The BGS Lexicon of Named Rock Units — Result Details

Middle Coal (Farrington Member, Somerset)

Computer Code: MLEC Preferred Map Code: notEntered
Status Code: Index Level
Age range: Asturian Substage (CAS) — Asturian Substage (CAS)
Lithological Description: Coal, although where the deposit splits into two seams, it is separated into two by by a band of seatearth around Old Mills Colliery (364500, 155500), whereas further away from the divide this, becomes 12 m of hard mudstone and fireclay, near Greyfield Colliery (364000, 158700).
Definition of Lower Boundary: The base of the bed is taken at the base of the coal resting upon about 9 m of hard mudstone of the underlying undivided Farrington Member.
Definition of Upper Boundary: The top of the coal is overlain by sandstone, which forms a hard roof, of the Middle Vein Greys. Elsewhere a planty shale developed between the coal and the sandstone of the surrounding Farrington Member.
Thickness: A thin coal, about 46 cm thick at Dunkerton in the northeast of the Somerset Coalfield, to 71 cm thick at Farrington in the southwest of the coalfield.
Geographical Limits: No.5 Vein, comprising the Dabchick and Peacock veins at Greyfield Colliery; Bromley No.4, -Possible correspondence; Smith's Vein.
Parent Unit: Farrington Member (FRF)
Previous Name(s): Middle Coal (Somerset) (-1056)
Middle Vein (-3549)
Alternative Name(s): Bromley No. 4
Smith's Vein
No. 5 Vein
Stratotypes:
none recorded or not applicable
Reference(s):
Kellaway, G A and Welch, F B A, 1993. Geology of the Bristol district. Memoir of the British Geological Survey Special Sheet [England and Wales]. 
Down, C G and Warrington, A J. 1971. The history of the Somerset Coalfield. [Newton Abbot: David and Charles.] 
Kellaway, G A. 1967. The correlation of the Upper Coal Measures of the Forest of Dean, Bristol and Somerset coalfields with those of the Midlands of England. In: Abstracts [of the] 6th International Congress of Carboniferous Stratigraphy and Geology, Sheffield, 1967. 
Collier, P. 1986. Collier's Way: History and walks in the Somerset Coalfield. [Bradford-on-Avon: Ex-Libris Press.] 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E264 E280 E281