| Computer Code: |
DCT |
Preferred Map Code: |
DCT |
| Status Code: |
Full |
| Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
| Lithological Description: |
Eutaxitic lapilli-tuff, composition probably dacitic (or andesitic), interpreted as pyroclastic flow deposit. |
| Definition of Lower Boundary: |
Base of lapilli-tuff rests on a non-sequence that occurs at the top of the Whinny Bank Formation - an interbedded succession of siltstone and andesitic lapilli-tuff. |
| Definition of Upper Boundary: |
Parallel bedded tuff and lapilli-tuff of the Po House Tuff Formation. |
| Thickness: |
To 30m |
| Geographical Limits: |
Wicham Valley:- between Bankside (SD 158 831) and Lacra Bank (SD 145 815) |
| Parent Unit: |
Po House Tuff Formation (PHT)
|
| Previous Name(s): |
Po House Tuffs (Part)
(-857)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Dog Crag, Po House Bank, Whicham Valley, Cumbria. |
| Reference(s): |
| British Geological Survey. 1994b. Millom Park, SD18SE, Solid and Drift, 1:10 000. (Keyworth, Nottingham: British Geological Survey.) |
| British Geological Survey. 1994a. Silecroft, SD18SW solid and drift 1:10 000. (Keyworth, Nottingham, British Geological Survey.) |
| Johnson, E W, Soper, N J, Burgess, I C, Ball, D F, Beddoe-Stephens, B, Carruthers, R M, Fortey, N J, Hirons, S, Merritt, J W, Millward, D, Roberts, B, Walker, A B and Young, B. 2001. Geology of the country around Ulverston. Memoir of the British Geological Survey, England and Wales, Sheet 48. |
| Mathieson, N A, 1986 Geology, structure and geochemistry of the Ordovician volcanic succession in south west Cumbria. Unpublished Ph.D. thesis, University of Sheffield. |
| Green, J F N, 1913. The older Palaeozoic succession of the Dudden Estuary. London, 23pp. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E048
|
