The BGS Lexicon of Named Rock Units — Result Details

Maplewell Group

Computer Code: CMV Preferred Map Code: CMP
Status Code: Full
Age range: Ediacaran Period (AD) — Ediacaran Period (AD)
Lithological Description: Varied sequence of meta volcaniclastic and meta tuffaceous sandstones, siltstones and mudstones with vitric tuffs and volcanic block-breccias (mainly dacitic).
Definition of Lower Boundary: Coarse-grained tuffs and breccias of the Benscliffe Breccia Member sharply overlie green-grey thinly bedded to laminated fine- to medium-grained volcaniclastic beds of the Blackbrook Reservoir Formation.
Definition of Upper Boundary: Sharply, possible unconformably overlain by the Brand Group. Latter consists locally of small-pebble conglomerate or coarse-grained volcaniclastic sandstone of the Hanging Rocks Conglomerate Formation.
Thickness: Approximately 2000m
Geographical Limits: The unit is distributed within the centre and flanks of the Charnwood anticline, generally between Nanpantan, Benscliffe Wood and High Sharpley.
Parent Unit: Charnian Supergroup (CHA)
Previous Name(s): Maplewell Series [Obsolete Name and Code: Use CMV] (-147)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Eastern Charnwood Forest (Nanpantan-Outwoods). 
Type Area  North-west Charnwood Forest (Charnwood Lodge Reserve). 
Reference(s):
Worssam, B C and Old, R A, 1988. Geology of the country around Coalville. Memoir of the British Geological Survey, Sheet 155 (England and Wales) 
Watts, W W, 1947. Geology of the ancient rocks of Charnwood Forest, Leicestershire. Leicester: Leicester Literary and Philosophical Society. 
Carney, J N. 1994. Geology of the Thringstone, Shepshed and Loughborough districts (SK41NW, SK41NE and SK51NW). British Geological Survey Technical Report WA/94/08. 
Moseley, J and Ford, T D, 1985. A stratigraphic revision of the Late Precambrian rocks of Charnwood Forest, Leicestershire. Mercian Geologist, Vol.10(I), 1-18. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E141