The violent story of Cumbria’s ancient volcanoes

Ian Francis and Bruce Yardley (UK) The violent eruption that occurred near the Pacific island of Tonga in January 2022 reminded the world of the ferocious power of volcanoes. The most destructive eruptions can bury huge areas in layers of ash and lava, generate tsunamis, and even alter the Earth’s climate by injecting vast quantities of ash and aerosol droplets high into the atmosphere. Modern Britain is luckily far from any active volcanoes (Vesuvius in Italy, and the volcanoes of Iceland are the nearest to us), but this was not always the case: geological evidence shows that around 455 million years ago, during the Ordovician Period,an intense, but short-lived, periodof volcanic activity took place inwhat is now the Lake District. The geological record of that activity is mainly found in Lakeland’s high and rugged central fells, stretching from Ennerdale and Wasdale in the west, across to Haweswater in the east. Most of the Lake District’s highest fells are found in this central belt, including the Coniston fells, Pillar, Great Gable, Kirk Fell, the Sca Fells, Esk Pike, Crinkle Crags, the Langdales, Helvellyn and High Street (Fig. 1). Fig. 1. Volcanic rocks form the high central fells of the Lake District. The image shows banded volcanic ash beds (tuffs) on the flank of Glaramara, looking east over Heron Crag (in shadow), Ullscarf, and beyond the Helvellyn range. (Photo: Stuart Holmes.) As far back as the early nineteenth century, those familiar with the rocks and landscape of the Lake District (such as … Read More