Field Weekend September 2003:

Sixteen people attended the weekend, enjoying two days in the field in glorious weather. On Saturday we spent the morning at the beach at Tonfanau, north of Tywyn, examining the glacial sequence in the cliffs, and looking at the erratics of mid-Jurassic age, which are thought to be derived from the sea floor to the west. After a pub lunch in Llwyngwril, John Mason led us along the beach at Friog, just south of Fairbourne, to look at the Cambrian sequence and quartz veining – thought to be of early Ordovician age and the equivalents of the veins of the Dolgellau gold belt.
The Sunday excursion was to Llangrannog, looking at channeled and slumped units, on Ynys Lochtyn, and in the cove just north of Llangrannog itself – where there is also a rich trace fossil assemblage, both beneath and on top of thin rippled sandstones.

Tonfanau beach

Tonfanau beach

Trace fossils at Llangrannog

Trace fossils at Llangrannog

 

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