Vatnajökull glacier, Iceland - small glacial flood from Bárðarbunga volcanic system
Saturday Aug 25, 2012 12:05 PM | BY: T
The glacial flash flood is currently going down the Skafta river towards the sea. Civil Defence Iceland reported that is not dangerous if people are staying away from the river bed.
The glacier flood is small for Icelandic standard, and similar to one last year in July from the same area of Vatnajökull glacier. Last year, it was probably caused by a minor eruption in this area, but the current flood seems to have been caused by hydrothermal melting of ice.
The Icelandic civil defense has published no further reports which means that the flood has remained small, but the seismogram shows again a number of earthquakes in the same area than Saturday. RÚV was interviewing an IMO specialist regarding the water system. Conductivity and consistence of the water indicate that there is something going on under Vatnajökull. There is also a clear H2S smell, which implies not to approach the upper course of Skaftá (poisonous gases), whereas the lower course is not touched by that.
IMO thinks that there will perhaps not come a real glacier flood, but only some water which is leaking from the Skaftá cauldron.
Jökulhlaups are a common event in Iceland with so many volcanoes covered by ice. A jökulhlaup is not necessarily caused by an eruption, but can be triggered by increased seismicity or temperature, or accumulation of melt water simply reaching a certain threshold.
The Skafta river where the glacial flood is expected to flow, takes the melting water of nearly 1400 sq. miles. The glacial flash floods are known to have a strong sulfur smell. Since the giant eruption of the Laki volcano which filled up the broad river valley with lava, there is no longer a well defined river bed.
The ringroad Nr. 1 passes the river but has not been closed. During the last big Jökulhlaup a few months ago, a bridge was swept away by the ice and had to be reconstructed.
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Wednesday, Feb 09, 2011
Another Icelandic volcano might be preparing itself for a new eruption. Bárdarbunga, a large central volcano at the NW end of the massive Vatnajökull ice cap, has recently shown increased seismic activity, the Icelandic Met Office is reported in an article of the Telegraph. These could be precursors to new activity. After all, Bárdarbunga is one of Iceland's most active volcanoes and is located quite on the center of the Icelandic hot spot. Its last eruption was in 1902-03. ... [more]