Computer Code: |
ULV |
Preferred Map Code: |
ULG |
Status Code: |
Full |
Age range: |
Caradoc Series (O4)
— Caradoc Series (O4) |
Lithological Description: |
Basaltic trachyandesite with rhyolitic tuff. |
Definition of Lower Boundary: |
Lies conformably on sandstones and siltstones, plus tuffs of the Cwm Eigiau Formation. |
Definition of Upper Boundary: |
Overlain by siltstones, sandstones and calcareous mudstones of the Dwyfach Formation. |
Thickness: |
About 500m |
Geographical Limits: |
Pwllheli area, northwest Wales. |
Parent Unit: |
Not Applicable (-)
|
Previous Name(s): |
none recorded or not applicable
|
Alternative Name(s): |
none recorded or not applicable
|
Stratotypes: |
Reference Section |
Exposures near Boduan. |
Reference(s): |
Rushton, A W A and Howells, M F. 1998. Stratigraphical framework for the Ordovician of Snowdonia and the Lleyn Peninsula. British Geological Survey Research Report, RR/99/08. |
Matley, C A and Heard, A, 1930. The Geology of the country around Boduan (south-west Carnarvonshire). Quarterly Journal of the Geological Society of London, Vol.86, 130-168. |
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
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