Ruthin & Berwyn U3A
GUIDED by group leader Isabel Stewart, the Ruthin & Berwyn U3A geology groups headed to the Great Orme, Llandudno for their September field trip.
They looked at the spectacular limestone in Bishop's Quarry, searched for fossils of brachiopods, crinoids and coral, walked on the limestone pavements and admired a sinkhole.
The limestone was formed between 350 and 360 million years ago in the Carboniferous Era and the limestone pavements were formed from 12,000 to 60,000 years ago during the last Ice Age, when the land was under a kilometre of ice.
The melting / moving ice scoured the surface of the limestone leaving it flat and devoid of soil and other coverings.
Sinkholes are formed when the limestone roof of an underground cave collapses.
Take care as the Great Orme is riddled with caves and old mines.
It was another delightful field trip.
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