| Computer Code: |
MRRT |
Preferred Map Code: |
MRT |
| Status Code: |
Full |
| Age range: |
Abereiddian Stage (O2)
— Abereiddian Stage (O2) |
| Lithological Description: |
Fine-grained, purple weathering, welded rhyolitic tuff. |
| Definition of Lower Boundary: |
Overlies mudstones and siltstones with coarse sandstone interbeds. |
| Definition of Upper Boundary: |
Overlain by mudstones and siltstones with coarse sandstone interbeds. |
| Thickness: |
none recorded or not applicable
|
| Geographical Limits: |
Pwllheli district, northwest Wales. |
| Parent Unit: |
Trygarn Formation (TGN)
|
| Previous Name(s): |
Mynydd Rhiw Rhyolitic Tuff Member [Obsolete Name and Code: Use MRRT]
(-2329)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
Displaced blocks around Mynydd Rhiw to Ty'n-y-mynydd. |
| Reference(s): |
| Fitch, F J, 1967. Ignimbrite volcanism in North Wales. Bulletin Volcanologique, 30, 199-219 |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E134
|
