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)
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Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
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Stratotypes: |
Type Area |
Carrock Fell |
Reference(s): |
Millward, D. 2002. Early Palaeozoic magmatism in the English Lake District. Proceedings of the Yorkshire Geological Society, Vol. 54, Part 2, 65-93. |
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.) |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E023
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