| Computer Code: |
MTGM |
Preferred Map Code: |
notEntered |
| Status Code: |
Pending Upgrade |
| Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
| Lithological Description: |
Porphyritic microgranite composed of perthite phenocrysts with lesser plagioclase and minor green biotite in an equigranular, unfoliated, granophyric groundmass |
| Definition of Lower Boundary: |
Not seen. |
| Definition of Upper Boundary: |
Not seen. |
| Thickness: |
Unknown. |
| Geographical Limits: |
none recorded or not applicable
|
| Parent Unit: |
Not Available (!)
|
| Previous Name(s): |
Mynydd Tir-Y-Cwmwd Granophyric Microgranite [Obsolete Name and Code: Use MTGM]
(-1712)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| none recorded or not applicable |
| 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
|
