The ongoing volcanic eruption near Reykjavik, which will pass the six-month mark on Sunday, is now the longest in the Nordic country in more than 50 years. Begun on the evening of March 19 near Mount Fagradalsfjall, located on the Reykjanes peninsula in the southwest of the Icelandic capital, the eruption has already attracted 300,000 curious people and visitors always flock to admire it.
With its slow and continuous flow, its spurts like a geyser or its spectacular overflows from the crater, the eruption officially baptized “Fagradalshraun” (“beautiful lava valley” in Icelandic) has become the most popular of Icelandic tourist attractions. .
143 million cubic meters of lava
Sixth eruption in Iceland for twenty years, this week it exceeded the eruption of the Holuhraun lava field, in east-central Iceland, which lasted from the end of August 2014 to the end of February 2015. “Six months it’s a reasonably long eruption, ”vulcanologist Thorvaldur Thordarson told AFP. We must now go back to the eruption that saw the emergence of the volcanic island Surtsey (1963-1967), in the archipelago of the Vestmann Islands, to find a longer volcanic episode.
The eruption near Mount Fagradalsfjall produced nearly 143 million cubic meters of lava in six months. After almost nine days of hiatus, lava resurfaced in early September. The volume remains relatively low, however, since it is eleven times less than the previous eruption in 2014-2015 in Holuhraun, which had caused the largest basaltic lava flow in the country for more than 230 years.
Like a wave on the sand
The current eruption stands out “in the sense that it maintains a relatively stable flow, but it has been quite vigorous,” notes Halldór Geirsson, a geophysicist at the Institute of Earth Sciences. Usually, Icelandic eruptions start very strong and then lose power. Accompanied by a powerful plume of smoke linked to degassing, the orange-red incandescent fluid spurts out from the crater.
But lava has also recently accumulated deep, through internal tunnels under visible layers already solidified, forming a pocket that eventually gives way under pressure. It then breaks like a wave breaking on the sand, under the conquered eye of visitors. According to figures from the Icelandic Tourist Board, nearly 300,000 people have already walked the dented and sloping sides of the small mountains overlooking the valleys of Geldingadalir, Meradalir and Nátthagi, where lava has poured.