Iceland’s volcano has baffled scientists: A decrease in seismic activity, while magma continues to build up underground in Iceland, has scientists wondering what could happen next, whether or not an eruption will occur in the area they suspected!
In an update on Friday, Iceland’s Meteorological Department said that while the current volcanism process is “not over”, it is “difficult to say when and where” the next magmatic levee will penetrate the Earth’s crust beneath the island nation. Meanwhile, the intrusion of molten rock into the Earth’s crust, which was reshaping the surface, continues to build “at a relatively steady rate.
“ The report said that “relatively few” earthquakes had been detected in the previous few days, most of which were magnitude 1 or less. Between 1,500 and 1,800 earthquakes were recorded per day from November 10 for nearly two weeks, before dropping to a few hundred.
Earthquakes have mostly occurred around a magma dyke, or magma dyke—a rapidly forming vertical sheet of molten rock that has passed through a weak spot in the Earth’s crust and is estimated to be about 9.3 miles long. Its course runs along the coastal fishing town of Grindavik, on the southwestern peninsula of Iceland’s main island.
This town with a population of 4,000 was evacuated last month due to the threat of a volcanic eruption.
Until now, experts have believed that if an eruption were to occur, it would most likely occur somewhere along the path of the dike.
Iceland’s Meteorological Department had previously said there was a high chance of an eruption in the area, before downgrading it to “possible” last week.
In its latest update, the agency said most of the seismic activity is occurring where the dyke is thought to be fed by a short-distance horizontal magma intrusion, which is rising at a rate of about one centimeter per day, but the ground around the dyke is much less than that. It was already swollen.
The Iceland Meteorological Agency said the process of dyke formation will continue and “it can be said with certainty that a phase has begun where a similar sequence of events may repeat itself in time.” But at this stage, it is impossible to say when the next intrusion of magma energy at a shallower depth might occur and whether it will occur in a similar region, he adds.
In recent weeks, Icelandic authorities have built earthen walls, along with conduits and channels, around Grindavik and Svartsengi, a nearby geothermal power plant, to divert lava away from buildings in the event of an eruption.
In the horizontal intrusion below Svartsengi — about 6 miles in diameter and believed to feed the dike — magma continues to build at depth, which experts previously said has occurred cyclically over the past few years.
An abrupt shift in the North American tectonic plate from the Eurasian plate is thought to have allowed magma to suddenly push upward through a rift beneath Iceland.
When seismic activity showed signs of abating, an Icelandic volcanologist expressed hope that the volcanism period was over, but told Newsweek that an “intense” period of tectonic activity in the region may be about to begin, based on trends be historical