| Computer Code: |
PCR |
Preferred Map Code: |
PC |
| Status Code: |
Full |
| Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
| Lithological Description: |
Rhyolitic domes, sills and tuffs associated with the Pitts Head Tuff and Llwyd Mawr Tuff. |
| Definition of Lower Boundary: |
Overlies sandstones, tuffs and siltstones of the Cwm Eigiau Formation. |
| Definition of Upper Boundary: |
Overlain by sandstones, tuffs and siltstones of the Cwm Eigiau Formation or ash-flow tuffs and breccias of the Lower Rhyolitic Tuff Formation. |
| Thickness: |
Up to 700m (including the Pitts Head Tuff). |
| Geographical Limits: |
Pwllheli area, northwest Wales. |
| Parent Unit: |
Pitts Head Tuff Formation (PT)
|
| Previous Name(s): |
none recorded or not applicable
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Reference Section |
Pen Ychain, near Pwllheli. |
| Reference(s): |
| Young, T P, Gibbons, W and McCarroll, D. 2002. Geology of the country around Pwllheli. Memoir of the British Geological Survey, Sheet 134 (England and Wales). |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E134
|
