IN THE LINE OF FIRE

AFTER THREE YEARS OF FIERY ERUPTIONS, EXPERTS ARE NOW CONFIDENT THAT ICELAND'S REYKJANES PENINSULA HAS ENTERED A NEW PHASE OF VOLCANIC ACTIVITY

- DR CLAIRE ASHER

A fiery beast has awoken from centuries of slumber. The past three years have seen it create cracks in Earth’s crust on the southwestern tip of Iceland and belch fountains of lava up through them. It’s captivated people worldwide and inspired a mix of awe and fear. Experts say that after 800 years of quiet, this beast – the Icelandic fault line – has entered a new period of activity that could last decades.

Located in the North Atlantic Ocean, Iceland is a hotspot of volcanic activity, with over 30 active volcanoes distributed across the 100,000km² (38,600-mile²) island. On average, an eruption occurs here once every three to five years, although they’re not evenly distributed over time and tend to come in clusters of activity, punctuated by periods of relative calm. Over the last 500 years, Iceland’s volcanoes have ejected one-third of all the lava that has flowed across Earth’s surface.

Its volatile temperament is a product of the island’s geological context. Iceland lies on the Mid-Atlantic Ridge, a rift between the North American and Eurasian tectonic plates, which are slowly moving apart at about 1cm (0.3in) each year, creating a growing crack in Earth’s crust. Iceland is also situated directly above an upwelling of molten rock, known as a mantle plume.

“Iceland is very volcanically active because there’s a [tectonic] plate boundary, the Mid-Atlantic Ridge, and there’s a mantle plume that comes from deep [below it],” explains Magnús Tumi Guðmundsson, professor of geophysics at the University of Iceland.