What’s on : Lectures
Iceland, the land of Fire and Ice
Dr Rebecca Williams, Reader in Volcanology, The University of Hull
Iceland, the land of fire and ice, is unique and spectacular and has long fascinated geologists and geographers. Its landscape is carved by the competing forces of volcanism and glaciation. Located above a divergent plate boundary and a hotspot, the island is dominated by basaltic volcanism. Recent eruptions at Fagradalsfjall have showcased the typical Icelandic style of volcanism, with fissure eruptions, lava fountains and lava flows, drawing huge crowds to marvel at the spectacle. However, these eruptions are not always tourist-friendly. The fissure eruption of Laki led to a famine that killed about 25% of the island’s population and resulted in a drop in global temperatures. This caused crop failures in Europe and may have caused excessive deaths in the UK. The interactions of the volcanoes with the icecaps in Iceland leads to particular eruption styles and landforms. The ice may constrain erupted material, may melt to create unique hazards, or lead to explosive eruptions as the cold ice meets the hot magma. The 2010 eruption of Eyjafjallajökull entered an explosive phase when more evolved magma was erupted under the summit glacier, sending an ash cloud across Europe grounding flights and causing travel chaos. This talk explores the fascinating geology of Iceland, comparing some of the most interesting eruptions and new advances that have been made in volcanology through their study.
Memorial Lecture in thanksgiving for the life of David Rowe.
7pm in the Tempest Anderson Lecture Theatre in the Yorkshire Museum
All Welcome. This is a free event although donations are also welcome.
IMAGE: Fagradalsfjall eruption 2022/ Creative Commons
Lecture in honour of David Rowe, whose son Max spoke about his father’s support for the YPS, his wide range of interests, and in particular his fascination with Iceland.
Iceland is only 25 million years old. It lies on the Mid-Atlantic Ridge where the Eurasian and North American tectonic plates draw apart and continue to form its spectacular landscapes. Thirty active volcanic systems lie under the island and magma plumes rise from hundreds of kilometres below to erupt through long fissures, or explosively from volcanic cones.
The lava also reacts with ice, meltwater and seawater in various ways. Iceland’s table mountains are an indication of the height and weight of the former icecap which reacted with magma leaving flat volcanic cones. Now, when magma reacts with ice and meltwater the result can be ash rather than lava eruption. In 2010 Eyjafjallajökull ejected vast ash clouds which disrupted air traffic over the North Atlantic and Europe for weeks. Much worse was the huge Laki fissure eruption of 1783-4 which produced sulphuric acid and fluorine aerosols. This toxic haze crossed Iceland and Europe and damaged crops, caused famine, and killed animals and people in large numbers. The haze was detected as far away as China.
When a volcanic eruption threatened to close their harbour in 1973, islanders on Heimaey diverted the lava flow by pumping seawater onto the leading edge. The island of Surtsey remains uninhabited since the 1963 undersea eruption which created it.