| Computer Code: |
GRCG |
Preferred Map Code: |
GrCg |
| Status Code: |
Full |
| Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
| Lithological Description: |
A massive, poorly sorted volcaniclastic breccia, comprising heterolithic volcanic clasts, including abundant pink-weathered rhyolite clasts. |
| Definition of Lower Boundary: |
The abrupt change from bedded volcaniclastic sandstone within the Mardale Sandstone Formation to volcaniclastic breccia. |
| Definition of Upper Boundary: |
Taken at the sharp base of the overlying thin unit of bedded volcaniclastic sandstone, which is succeeded by massive, weakly eutaxitic, dacitic lapilli-tuff. |
| Thickness: |
To 180m |
| Geographical Limits: |
Swindale, Cumbria, between Dry Grove Gill [NY 510 122] and Mullender [NY 522 132]. |
| Parent Unit: |
Mardale Sandstone Formation (MRL)
|
| Previous Name(s): |
Gouther Crag Member
(-940)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Gouther Crag, 500m south of Truss Gap, Swindale, 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
|
