| Computer Code: |
SRN |
Preferred Map Code: |
Srn |
| Status Code: |
Full |
| 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 Applicable (-)
|
| 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, Tietzch-Tyler, D, Horak, J M, and Murphy, F C. 1994. 75-84 in Precambrian rocks in Anglesey, southwest Llyn and southeast Ireland. 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. |
| 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. |
| 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. |
| 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: HMSO.) 88pp. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
|
E133
E134
|
