The BGS Lexicon of Named Rock Units — Result Details

Sharpley Porphyritic Dacite

Computer Code: SYP Preferred Map Code: SyP
Status Code: Full
Age range: Ediacaran Period (AD) — Ediacaran Period (AD)
Lithological Description: Grey to pale purple, massive, fine-grained matrix porphyritic (quartz and feldspar) dacite. Quartz phenocrysts commonly rounded and green in colour.
Definition of Lower Boundary: Sharp, possibly intrusive contact with Swannymote Breccia Member. Other contacts seen are faulted.
Definition of Upper Boundary: Sharp, possibly intrusive contact with Swannymote Breccia Member. Other contacts seen are faulted.
Thickness: c.0-450m
Geographical Limits: Exposed between High Sharpley and Whitwick Quarry.
Parent Unit: Whitwick Volcanic Complex (WVO)
Previous Name(s): Porphyroid Of Sharpley Type (-1854)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  High Sharpley. 
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. 
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. 
Watts, W W, 1947. Geology of the ancient rocks of Charnwood Forest, Leicestershire. Leicester: Leicester Literary and Philosophical Society. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E141