Notes on the structure and relations of the pre-cambrian and ordovician rocks of southwestern lleyn (Caernarvonshire)

✍ Scribed by R. M. Shackleton

• Book ID: 102846231
• Publisher: John Wiley and Sons
• Year: 1951
• Tongue: English
• Weight: 622 KB
• Volume: 1
• Category: Article
• ISSN: 0072-1050
• DOI: 10.1002/gj.3350010408

✦ Synopsis

Abstract

The oldest visible Pre‐Cambrian rocks in Lleyn are pillow lavas and sediments of the Gwna Group. They are succeeded by rhyolitic tuffs (Gwyddel Beds). Schists and gneisses have been formed from these rocks. The Sarn adamellite intrusion is related to the gneisses. The Pre‐Cambrian rocks are unconformably overlain by Ordovician.