The Icelandic Coast Guard flew a team of scientists across Mýrdalsjökull glacier and the flooded area yesterday to examine the circumstances. They estimate that the two calderas in the southern part of the glacier from which the flood emerged are 50 meters deep.
One of the calderas. Photo posted on ruv.is. Copyright: Icelandic Coast Guard.
The scientists estimate the depth based on ash layers in the ice. The black stripe that can be seen in the walls of the calderas is ash from the volcanic eruption in Eyjafjallajökull last year, while the edges of the calderas are black because of the ash from the recent Grímsvötn eruption, ruv.is reports.
Their vertical walls indicate that the glacial melt occurred very quickly. It was caused either by a magma intrusion or a steam explosion. The cracks around the calderas are extremely deep and wide—they could swallow a whole house.
They are located in the southernmost part of the Katla crater, which measures 80 square kilometers. It is ten kilometers wide and 500-600 meters deep and is surrounded by mountains, the highest of which are 1,300 meters high.
A thick ice covers the crater, which makes Katla one of the most dangerous volcanoes in Iceland. In case of a large eruption in Katla, a significant amount of ice could melt and cause a huge flood, which could prove dangerous for people living in the area.
Katla last erupted in 1918, which was a large eruption.
The recent activity in Mýrdalsjökull does not indicate an immediate eruption and the activity in the glacier has subsided.
Click here to read an announcement in English and German about the situation.
Click here to read more about the current situation in Mýrdalsjökull.