Granite Meets Mudstone The Bay of Trespassers, Brittany

At the Bay of Trespassers in Brittany, France, the coastline tells a story written 300 million years ago.

Here, massive granite intrusions sit side by side with mudstones, their contact exposed in sea caves and cliff faces. These rocks were forged deep below ancient mountain ranges during the Variscan Orogeny, the same event that shaped the granites of Cornwall.

Standing on this clifftop, you can see the boundary where granite and metamorphosed mudstones meet, a reminder that France and Cornwall once shared the same geological journey, long before the Atlantic Ocean opened between them.

Join me, the Down to Earth Geologist, as I explore this spectacular contact zone and uncover the deep-time processes that shaped this dramatic coast.

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