Computer Code: |
GWF |
Preferred Map Code: |
notEntered |
Status Code: |
Index Level |
Age range: |
Harnagian Substage (OG)
— Harnagian Substage (OG) |
Lithological Description: |
[Obsolete] Shales and mudstones with Godor Lava passing to Godor Ash at the top of the unit. |
Definition of Lower Boundary: |
Drawn at the base of the Gwern Feifod Group. Shales and mudstones where it rests conformably on shales with thin pyroclastic bands of the Garwallt Group. |
Definition of Upper Boundary: |
Drawn at the conformable upward passage from the Gwern-Feifod Lava of the Gwern-Feifod Group to the Mynydd Tarn Ash Formation of the Mynydd Tarn Group. |
Thickness: |
Not defined. |
Geographical Limits: |
Berwyn Hills, Montgomeryshire. |
Parent Unit: |
none recorded or not applicable
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Type Area |
Godor approximately 6kms north west of Llanrhaiadr. |
Reference(s): |
Cantrill, T C, et al, 1914. Summary of Progress of the Geological Survey of Great Britain for 1914, (1915) 7. |
Wedd, C B, Smith, B, King, W B R and Wray, D A. 1929. Geology of the country around Oswestry. Memoir of the Geological Survey of Great Britain, Sheet 137. |
Williams, A and others, 1972. A correlation of Ordivician rocks in the British Isles. Geological Society of London Special Report No.3. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
none recorded or not applicable |