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Bárðarbunga Volcano, Under The Ice Cap of Vatnajökull Glacier, Showing Signs of Possible Eruption
Bárðarbunga volcano, an active subglacial stratovolcano located in Iceland under the huge Vatnajökull Glacier, has recently had hundreds of earthquakes that scientists believe are from the movement of underground magma.
Bárðarbunga volcano is a subglacial ( under a glacier ) stratovolcano.
A stratovolcano, also known as a composite volcano, is a conical volcano built up by many layers (strata) of hardened lava, tephra, pumice, and volcanic ash. Unlike shield volcanoes, stratovolcanoes are characterized by a steep profile and periodic explosive eruptions and quiet eruptions, although some have collapsed craters called calderas. ⓐ
Bárðarbunga has been rumbling at least since last Saturday.
The intense earthquake swarm continues with no significant changes. There are no signs of magma migrating towards or reaching the surface are present, although the risk of a subglacial eruption in the near future remains high. This could lead to significant glacial floods and ash emissions, which in turn could cause again disruptions of flight operations in the region, depending on the wind trajectories and the amount of ash released. ⓑ
Earthquake activity has recently increased underneath Bárðarbunga.
A magnitude 4.0 earthquake hit in Bárðarbunga volcano at around 11:00 am this morning. The earthquake was at a depth of 3 km, which is much shallower than most of the other earthquakes in the area in recent days. Two other earthquakes, of magnitude 3.8, also occurred in the volcano before midday, ruv.is reports. ⓒ
Scientists are worried that the possible eruption of this volcano may cause massive flooding in Iceland.
In Iceland people wait for the possible eruption of Bárðarbunga volcano with a strange combination of excitement and anxiety. The earthquakes continued through Wednesday night and into Thursday morning, but there is still no sign of magma making its way to the surface. Scientists are cautious because nobody wants to be the one who falsely predicted an eruption, but even so they seem to be leaning towards the opinion that probably the old volcano is waking up. ⓓ
The eruption would be under a glacier between 150 and 600 meters thick. That means the ice would melt and Jökulsá á Fjöllum, a glacial river, would flood. The river might increase 10 to 40-fold. After the start of an eruption the water would take about an hour to reach the border of the glacier. It would be at Herðubreiðarlindir in four and a half hours, at the bridge by Grímsstaðir in seven hours and down to Ásbyrgi, a natural pearl [port], in about nine hours. ⓓ
This volcano could also cause disruptions to air travel.
A volcanic eruption in Bárðarbunga could have a great an impact on air travel as the 2010 Eyjafjallajökull eruption did, according to Friðþór Eydal, a spokesperson for ISAVIA, the company which operates airports in Iceland. ⓔ
There have been no observations of migration towards the surface or any other signs of imminent or ongoing volcanic activity. We cannot exclude that the current activity will result in an explosive subglacial eruption, leading to an outburst flood (jökulhlaup) and ash emission."
Icelandic Met Office
Throughout history there have been large eruptions every 250–600 years. The last large eruption was in 1480.
Eruptions appear to follow a cycle: there were several eruptions in the glacier between 1701–40 and since 1780. There hasn’t been an eruption in the glacier or the system since 1862-4.
ⓐ WIKI Stratovolcano
ⓑ Volcano Discovery
Bárdarbunga volcano (Iceland): continuing earthquakes, no signs of magma rising to surface
ⓒ Iceland Review, On Line August 21, 2014 14:35
Magnitude 4.0 Earthquake in Bárðarbunga
ⓓ Iceland Review, On Line August 21, 2014 07:15
Eruption May Cause Monumental Flood
ⓔ Iceland Review, On Line August 20, 2014 14:04
Disruption to Air Traffic Could be Significant
For the latest information go to Ríkisútvarpið RUV – The Icelandic National Broadcasting Service. They have the volcano news in English.
Live Webcam of Bárðarbunga
Image: Icelandic Met Office
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