The BGS Lexicon of Named Rock Units — Result Details

Carrock Fell Complex

Computer Code: CFCO Preferred Map Code: symb
Status Code: Full
Age range: Ordovician Period (O) — Ordovician Period (O)
Lithological Description: Layered cumulate gabbros and quartz-gabbros, forming the Mosedale Intrusions which have a calc-alkaline/transitional to tholeiitic composition, microgabbro, microgranite with apatite-bearing iron-rich microdiorite, micromonzodiorite and microgranite zones forming the tholeiitic Carrock Intrusions, quartz-phyric rhyolite of the Harestones Rhyolite, and a microgranite named the Iron Crag Microgranite. Several component intrusions have Ordocician radiometric ages (Mosedale Gabbros, Carrock intrusions).
Definition of Lower Boundary: Not defined.
Definition of Upper Boundary: Not defined.
Thickness: A near-vertical, sheet-like mass of about 8.5 sq. km emplaced at the junction between the Skiddaw Group and the Eycott Volcanic Group.
Geographical Limits: Carrock Fell, Cumbria.
Parent Unit: Lake District Ordovician Mafic Plutonic Suite (LDMP)
Previous Name(s): none recorded or not applicable
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Carrock Fell 
Reference(s):
Stephenson, D, Bevins, R E, Millward, D, Highton, A J, Parsons, I, Stone, P and Wadsworth, W J, 1999. Caledonian igneous rocks of the British Isles. (Peterborough: Joint Nature Conservation Committee.) 
Hunter, R H and Bowden, N, 1990. Itinerary 3: The Carrock Fell Igneous Complex. 57-67 in Moseley, F (ed.) The Lake District. Geologists' Association Guide. 
Hunter, R H, 1980. The petrology and geochemistry of the Carrock Fell Gabbro-granophyre Complex, Cumbria. (University of Durham: PhD thesis.) 
Millward, D. 2002. Early Palaeozoic magmatism in the English Lake District. Proceedings of the Yorkshire Geological Society, Vol. 54, Part 2, 65-93. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E023