| Computer Code: |
DHD |
Preferred Map Code: |
DHd |
| Status Code: |
Full |
| Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
| Lithological Description: |
Massive units of heterolithic volcaniclastic breccia and sandstone. |
| Definition of Lower Boundary: |
Base of volcaniclastic breccia and sandstone. Overlies unnamed basaltic andesite lava and locally a thin (3m) tuff. Probably unconformable. |
| Definition of Upper Boundary: |
Succeeded by overlying parts of the Birker Fell Andesite Formation, including the Cockley Beck Tuff (garnetiferous, dacitic lapilli tuff) and a variety of basaltic andesite and andesite lava. |
| Thickness: |
0 - 220m |
| Geographical Limits: |
Dale Head - Cockley Beck area in the Duddon Valley, Cumbria. |
| Parent Unit: |
Birker Fell Andesite Formation (BFA)
|
| Previous Name(s): |
Dale Head Member [Obsolete Name and Code: Use DHD]
(-2751)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Dale Head to Rowantree How. |
| Reference(s): |
| Millward, D, Johnson, E W, Beddoe-Stephens, B, Young, B, Kneller, B C, Lee, M K, Fortey, N J, Allen, P M, Branney, M J, Cooper, D C, Hirons, S, Kokelaar, B P, Marks, R J, McConnell, B J, Merritt, J W, Molyneux, S G, Petterson, M G, Roberts, B, Rundle, C C, Rushton, A W A, Scott, R W, Soper, N J, and Stone, P. 2000. Geology of the Ambleside district. Memoir of the British Geological Survey, England and Wales, Sheet 38. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E038
|
