Computer Code: |
RWT |
Preferred Map Code: |
Rwt |
Status Code: |
Full |
Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
Lithological Description: |
A well-bedded dacitic tuff and lapilli-tuff, with some pyroclastic breccia and accretionary lapilli-tuff, more thinly-bedded, finer grained and better sorted upwards, with abrupt intra-bed changes in grain size common. |
Definition of Lower Boundary: |
Taken at the abrupt change from bedded volcaniclastic sandstone to bedded pyroclastic rocks. |
Definition of Upper Boundary: |
Intruded by andesite sills at the base of the overlying Mardale Formation. |
Thickness: |
Up to 100 m thick. |
Geographical Limits: |
Southeast of Haweswater Reservoir, Cumbria, between Rowantreethwaite Beck and Woof Crag. |
Parent Unit: |
Mardale Sandstone Formation (MRL)
|
Previous Name(s): |
Rowantreethwaite Member [Obsolete Name and Code: Use RWT]
(-3016)
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Section |
Ritchie Crag, 1.7 km SSE of the Haweswater Hotel, Haweswater, Cumbria. |
Reference(s): |
Millward, D. 2002. Geology of the area between Haweswater and Shap. British Geological Survey Research Report RR/02/02. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E030
E039
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