The subsidence of the Bárðarbunga caldera measures 50 meters (164 feet) since the volcanic eruption in Holuhraun began in late August. The lava erupting in Holuhraun originates in the Bárðarbunga magma chamber under Vatnajökull glacier.
Scientists from the University of Iceland’s Earth Science Institute flew over the site on Thursday measuring to what extent the ice above the Bárðarbunga caldera has sunk. They concluded that the eruption in Holuhraun will in all likelihood continue, ruv.is reports.
“The results after [Thursday’s] observation flight tell us that it is not about to come to an end. The conditions are similar,” stated geophysicist Magnús Tumi Guðmundsson. “Another scenario is that the eruptive fissure will move under the glacier but that is less likely. A third scenario is an eruption in Bárðarbunga itself but that’s the least likely option of the three.”
Recent evidence indicates that the magma under Bárðarbunga reaches a depth of two to three kilometers (1.4-1.8 miles) below the glacier’s surface. “However, the results of petrology studies of the magma show unambiguously that it hasn’t erupted from a depth lower than nine kilometers,” Magnús pointed out.
That indicates that the magma system below Bárðarbunga is not just one chamber high up in the earth’s crust but several. “Or that it is considerably high, several kilometers high, and that the magma is erupting from the bottom and that the magma at the top isn’t moving up but sinking,” Magnús explained.