Computer Code: |
SRN |
Preferred Map Code: |
Srn |
Status Code: |
Pending Upgrade |
Age range: |
Ediacaran Period (AD)
— Ediacaran Period (AD) |
Lithological Description: |
Locally foliated granites, granodiorites, diorites and hornblende gabbros with garnetiferous gneiss in places. |
Definition of Lower Boundary: |
None. |
Definition of Upper Boundary: |
None. |
Thickness: |
Unknown. |
Geographical Limits: |
Lleyn Peninsula, Sheet 113 (Aberdaron and Bardsey Island), although the complex probably extends offshore. The boundaries of the intrusive complex are largely sheared along the Lleyn Shear Zone. |
Parent Unit: |
Not Available (!)
|
Previous Name(s): |
Sarn Granite
(-543)
|
Alternative Name(s): |
Rhos Hirwain Synenite
|
Stratotypes: |
Reference Section |
Mynydd Cefnamlwch. Gibbons W and McCarroll D. 1993. |
Reference Section |
Afon Fawr, 600 m downstream from Pont Llangwnnadl. Gibbons W and McCarroll D. 1993. |
Reference Section |
Flanks of Pen y Gopa. Gibbons W and McCarroll D. 1993 |
Reference Section |
Hilltop east of Meillionydd Farm. Gibbons W and McCarroll D. 1993. |
Reference Section |
Craig Fael.. Gibbons W and McCarroll D. 1993 |
Reference Section |
Foreshore 150 m south of Penrhyn Nefyn. Gibbons W. 2000. Penrhyn Nefyn. |
Reference(s): |
Gibbons W and McCarroll D. 1993. Geology of the country around Aberdaron, including Bardsey Island. Memoir of the British Geological Survey, Sheet 133 (England and Wales). (London: H.M.S.O.). 88pp. |
Shackleton, R M. 1956. Notes on the structure and relations of the Precambrian and Ordovician rocks of southwestern Lleyn (Carnarvonshire). Geological Journal, Vol.1. 400-409. |
Gibbons, W, Tietzch-Tyler, D, Horak, J M and Murphy, F C. 1994. Precambrian rocks in Anglesey, southwest Llyn and southeast Ireland. 75-84. In Gibbons, W and Harris, A L (editors), A revised correlation of Precambrian rocks in the British Isles. Geological Society of London Special Report No 22. |
Matley C A. 1928. The Pre-Cambrian complex and assocciated rocks of south-western Lleyn (Carnarvonshire). Quarterly Journal of the Geological Society of London, Vol. 84, 440-501. |
Matley C A and Smith B. 1936. The age of the Sarn Granite. Quarterly Journal of the Geological Society of London, Vol. 92, 188-200. |
1:50K maps on which the lithostratigraphical unit is found, and map code used: |
E133
E134
|