Computer Code: |
GRY |
Preferred Map Code: |
Gry |
Status Code: |
Full |
Age range: |
Guadalupian Epoch (PUG)
— Lopingian Epoch (PUL) |
Lithological Description: |
Grey mudstones and siltstone, containing fragmentary plant remains together with thin impersistent limestone beds, seen as a muddy sandstone in the south. |
Definition of Lower Boundary: |
Taken at the base of a sequence of grey mudstones overlying breccia, elsewhere resting on reddened Carboniferous rocks. |
Definition of Upper Boundary: |
Defined by the base of the 'Magnesian Limestone' where present, or by the basal rocks of the St Bees Shale Formation. |
Thickness: |
From 10 m to 20 m thick. |
Geographical Limits: |
Barrow-in-Furness. |
Parent Unit: |
St Bees Evaporite Formation (SBE)
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Reference Section |
Haverigg Haws borehole, SD17NW/2. Rose and Dunham, 1977. |
Reference(s): |
Rose, W C C. 1977. Geology and Hematite deposits of South Cumbria. Economic Memoir for 1:50,000 Sheet 58 and southern part of Sheet 48. Memoir of the geological Survey of Great Britain. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E058
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