The BGS Lexicon of Named Rock Units — Result Details

Cawdale Tuff Member

Computer Code: CAWD Preferred Map Code: Cawd
Status Code: Full
Age range: Caradoc Series (O4) — Caradoc Series (O4)
Lithological Description: A massive, coarse tuff and tuff-breccia, with localised pyroclastic breccia and pebbly volcaniclastic sandstone.
Definition of Lower Boundary: Taken at the abrupt change to bedded pyroclastic rocks from either silicic lapilli-tuff of the Whelter Knotts Formation or from bedded volcaniclastic sandstone within the Mardale Formation.
Definition of Upper Boundary: Taken at the abrupt change to bedded volcaniclastic sandstone of the main part of the Mardale Formation.
Thickness: To 80m
Geographical Limits: Between Ullswater and the Haweswater Reservoir, eastern Lake District, Cumbria.
Parent Unit: Mardale Sandstone Formation (MRL)
Previous Name(s): Cawdale Member [Obsolete Name and Code: Use CAWD] (-111)
Alternative Name(s): none recorded or not applicable
Stratotypes:
Type Area  Four Stones Hill Beddoe-Stephens, 2000. 
Reference(s):
Beddoe-Stephens, B. 2000. The Borrowdale Volcanic Group between Haweswater and eastern Ullswater. British Geological Survey Technical Report WG/00/04. 
1:50K maps on which the lithostratigraphical unit is found, and map code used:
E030 E039