The BGS Lexicon of Named Rock Units — Result Details

Swannymote Breccia Member

Computer Code: SYB Preferred Map Code: SB
Status Code: Full
Age range: Ediacaran Period (AD) — Ediacaran Period (AD)
Lithological Description: Volcanic block-breccia, angular to sub-rounded blocks of porphyritic (quartz-feldspar) dacite in a crystal-rich coarse tuff matrix.
Definition of Lower Boundary: Not seen, unit may be wholly enclosed within Sharpley Porphyritic Dacite.
Definition of Upper Boundary: Sharp contact with overlying Sharpley Porphyritic Dacite; contact is either stratigraphical or the latter unit is intrusive into member.
Thickness: 0-120m
Geographical Limits: The unit is discontinuous and poorly exposed; the quoted type section and Ratchet Hill reference section are the only known exposures outside Whitwick Quarry.
Parent Unit: Charnwood Lodge Volcanic Formation (CMCL)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Swannymote Rock, and outcrops 200m to west. 
Reference Section  Ratchett Hill. 
Reference Section  Whitwick Quarry. 
Reference(s):
Carney, J N, 1994. Geology of the Thringstone, Shepshed and Loughborough districts (SK41NW, SK41NE and SK51NW). British Geological Survey Technical Report WA/94/08. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E141