The BGS Lexicon of Named Rock Units — Result Details

Lowcray Tuff Formation

Computer Code: LOCY Preferred Map Code: Locy
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: Crystal-rich parataxitic tuff and lith-rich coarse lapilli-tuff, locally with a weak eutaxitic fabric, much hematised and silicified.
Definition of Lower Boundary: Not seen but mapped at the change from densely welded andesitic tuff of the Fleming Hall Formation to a mixture of lithic lapilli-tuff and crystal rich tuff.
Definition of Upper Boundary: Defined by the base of the overlying rhyolitic welded tuff of the Blengdale Formation.
Thickness: About 650m
Geographical Limits: Restricted to the area west of the Thistleton Fault (Lake District Boundary Fault Zone), Cumbria.
Parent Unit: Borrowdale Volcanic Group (BVG)
Previous Name(s): Lowcray Formation (-2915)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Section  Lower reaches of the River Bleng, West Cumbria. 
Reference(s):
Akhurst, M C, Chadwick, R A, Holliday, D W, McCormac, M, McMillan, A A, Millward, D, Young, B, Ambrose, K, Auton, C A, Barclay, W J, Barnes, R P, Beddoe-Stephens, B, James, J C W, Johnson, H, Jones, N S, Glover, B W, Hawkins, M P, Kimbell, G S, MacPherson, K A T, Merritt, J W, Milodowski, A E, Riley, N J, Robins, N S, Stone, P and Wingfield, R T R. 1997. The geology of the west Cumbria district. Memoir of the British Geological Survey, Sheets 28, 37 and 47 (England and Wales). 138pp. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E037