The BGS Lexicon of Named Rock Units — Result Details

Haweswater Intrusions

Computer Code: HAWS Preferred Map Code: symb
Status Code: Full
Age range: Ordovician Period (O) — Ordovician Period (O)
Lithological Description: Dolerite with subordinate gabbro and microdiorite, and minor intrusive breccia. No radiometric age has been published but an Ordovician age is inferred because of geochemical similarities with the Borrowdale Volcanic Group and the presence of cleavage in parts of the gabbro.
Definition of Lower Boundary: Not defined.
Definition of Upper Boundary: Not defined.
Thickness: At least eight plugs and dyke-like masses within a total area of 19km2, and having a combined outcrop of about 2.6km2.
Geographical Limits: Around the Haweswater Reservoir, from Willdale Beck [NY 483 166] to Harper Hills [NY 510 140]., Cumbria.
Parent Unit: Lake District Ordovician Mafic Plutonic Suite (LDMP)
Previous Name(s): Haweswater Complex [Obsolete Name And Code: See HAWS] (HAWC)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Wallow Crag to Kit Crag, south-east of Haweswater, Cumbria. Millward and Beddoe-Stephens 1998. 
Reference(s):
Millward, D, and Beddoe-Stephens, B. 1998. The Haweswater intrusions. British Geological Survey Technical Report WA/98/60. 
Nutt, M J C, 1979. The Haweswater Complex. 727-733 in The Caledonides of the British Isles - reviewed. Harris, A L, Holland, C H and Leake, B E (editors). Geological Society of London Special Publication 8. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E030 E039