The molten rock that has been building up beneath southwest Iceland has erupted in spectacular fountains of lava.
A gash two miles long has opened up on the Reykjanes peninsula, spewing between 100 and 200 cubic metres of lava every second. That’s far more than in other recent eruptions in the area.
Incredible footage shows spewing lava – live updates
There had been a prolonged pause in the volcanic rumblings.
It’s five weeks since 4,000 people were evacuated from the nearby fishing town of Grindavik in the middle of the night after an intense swarm of earthquakes.
But seismic activity petered out in the following days and scientists began to wonder whether the magma would solidify and never reach the surface.
But on Monday night there was another earthquake swarm and the surface ripped open soon after.
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The lava is currently flowing about half a mile an hour north and west, away from the town, which is little more than a mile from the southern end of the eruption.
But the rip in the Earth has been extending and if it reaches a south-facing slope then the town could be at risk.
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The Svartsengi power station, which provides electricity to thousands of homes, also seems to be safe for now. The authorities have been building a wall of rock and dirt to protect the facility from any lava flow.
According to the Icelandic Met Office, the seismic and GPS data suggests the eruption has eased as the night has progressed. But that doesn’t mean it will be a short-lived burst of volcanic activity.
It’s likely that the vast pressure that has pushed the magma towards the surface has been reduced.
Scientists will want to have a close look at the eruption area in daylight to get a better idea of what’s going on.
The authorities had plenty of warning this could happen and people have been moved out of harm’s way.
It is now a matter of just letting nature take its course.