| Computer Code: |
GFS |
Preferred Map Code: |
GFS |
| Status Code: |
Full |
| Age range: |
Gorstian Age (SG)
— Gorstian Age (SG) |
| Lithological Description: |
Mudstones, bedding-fissile, silty, grey-brown (when weathered); largely graptolitic hemipelagite. |
| Definition of Lower Boundary: |
Passage into undifferentiated Nantglyn Flags. |
| Definition of Upper Boundary: |
(SO 2135 9014) Overlain by Bailey Hill Formation which in places includes the Dingle Mudstone Member at its base. |
| Thickness: |
<100m |
| Geographical Limits: |
Western parts 1:50,000 map sheet 165 (Montgomery). |
| Parent Unit: |
Not Available (!)
|
| Previous Name(s): |
Lower Ludlow Graptolitic Shales [Obsolete Name and Code: Use GFS, OAK]
(-4060)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Western parts of 1:50 000 map sheet 165 (Montgomery). |
| Reference Section |
Gyfenni Wood Forestry track. Base of member not exposed, but top part is very well exposed to the base of the Bailey Hill Formation. |
| Type Section |
Stream section. |
| Reference(s): |
| none recorded or not applicable |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E165
|
