The BGS Lexicon of Named Rock Units — Result Details

Harestones Rhyolite

Computer Code: CFCOH Preferred Map Code: notEntered
Status Code: Full
Age range: Ordovician Period (O) — Ordovician Period (O)
Lithological Description: A quartz-phyric rhyolite. Radiometric age: 419 +/- 4 Ma (Rb-Sr, whole rock) (Rundle, 1979); considered by many authors including Millward (2002) to have been re-set.
Definition of Lower Boundary: Not defined.
Definition of Upper Boundary: Not defined.
Thickness: A near-vertical mass emplaced within the Drygill Shale Formation at the northern margin of the Carrock Fell Complex.
Geographical Limits: Carrock Fell, Cumbria.
Parent Unit: Carrock Fell Complex (CFCO)
Previous Name(s): Harestones Rhyolite [In Carrock Fell Complex] (-3916)
Harestones Felsite [Obsolete Name And Code: Use CFCOH] (HARE)
Alternative Name(s): none recorded or not applicable
Type Area  Great Lingy Hill. Millward (1999). 
Eastwood,T, Hollingworth, S E, Rose, W C C and Trotter, F M. 1968. Geology of the country around Cockermouth and Caldbeck. Memoir of the Geological Survey of Great Britain, England and Wales, Sheet 23. 
Millward, D. 2002. Early Palaeozoic magmatism in the English Lake District. Proceedings of the Yorkshire Geological Society, Vol. 54, Part 2, 65-93. 
Rundle, C C, 1979. Ordovician intrusions in the English Lake District. Journal of the Geological Society of London, Vol.136, 29-38. 
1:50K maps on which the lithostratigraphical unit is found, and map code used: