
Geology
St Abb’s Head is a rocky promontory by the village of St Abbs in Berwickshire, and a national nature reserve administered by the National Trust of Scotland.
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St Abb's Head National Nature Reserve, managed by National Trust for Scotland © Lawson Wood Ocean Eye Films
The layered sedimentary rocks of greywacke and siltstone which lie to the north and south of the Head were laid down at the bottom of the sea between 460 and 410 million years ago.
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The Head itself is made from hard volcanic rock which formed as lava flowed from volcanoes around 400 million years ago.
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The different types of rock account for the contrast in colour between the rocks of the Head and those of mainland cliffs. The softer sedimentary rocks have eroded over time, leaving behind the high headland made from the harder rock.
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