| Computer Code: |
PTR |
Preferred Map Code: |
Ptr |
| Status Code: |
Full |
| Age range: |
Telychian Age (ST)
— Telychian Age (ST) |
| Lithological Description: |
Thinly interbedded turbidite sandstones and mudstones with abundant thicker beds of argillaceous coarse sandstone. |
| Definition of Lower Boundary: |
Base of lowest thick argillaceous sandstone bed above the lower tongue of the Glanyrafon Formation. |
| Definition of Upper Boundary: |
Top of highest thick argillaceous sandstone bed below the upper tongue of the Glanyrafon Formation. |
| Thickness: |
Up to 300m. |
| Geographical Limits: |
Central Wales. |
| Parent Unit: |
Cwmystwyth Grits Group (CWY)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Section |
Pysgotwr Fawr stream section north-west of Bryn-Glas. |
| Reference(s): |
| Davies, K A. 1933. The geology of the area between Abergwesyn ( Breconshire) and Pompsaint (Carmarthenshire). Quarterly Journal Geological Society, London, Vol. 89, 172-200. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E195
E179
|
