New fissure openings have formed several times since the eruption at Fagradalsfjall, Iceland began on March 19, 2021. On May 2, the activity at the volcano changed, producing huge lava fountains -- the biggest since the eruption started. The video was captured by Sigfús Steindórsson around 02:00 local time on May 2.
Lava fountains were seen reaching about 300 m (985 feet) above ground lasting from 3 to 10 minutes.
The Icelandic Met Office (IMO) confirmed considerable changes in volcanic activity, starting at around 01:00 LT on May 2.
"It's not clear what causes these changes in volcanic activity, but it cannot be ruled out that there have been changes in magma flow, the chemical composition of magma/gas or that there have been changes in the feed system," IMO said.
"In light of this changed activity, the size of the danger area at the eruption sites is being reassessed."
The Krýsuvík-Trölladyngja volcanic system is described by the Catalogue of Icelandic Volcanoes as an approximately 50 km (31 miles) long composite fissure swarm trending about N38°E, including a 30 km (18 miles) long swarm of fissures, with no central volcano.
It is one of the volcanic systems arranged en-echelon along the Reykjanes Peninsula west of Kleifarvatn lake.
The Fagradalsfjall and Krýsuvík fissure swarms are considered splits or secondary swarms of the Krýsuvík–Trölladyngja volcanic system.
Small shield volcanoes have produced a large portion of the erupted volume within the system.
Several eruptions have taken place since the settlement of Iceland, including the eruption of a large basaltic lava flow from the Ogmundargigar crater row around the 12th century.
The latest eruption, identified through tephrochronology, took place during the 14th century.
Featured image credit: Hawaiian National Guard (stock)