Volcano activity of August 23-24-25, 2u012 - Glacial Flood at Vatnajökull (Iceland)

This (almost) daily post intends to follow up the activity changes of volcanoes all over the world.
This post is written by geologist Richard Wilson who specializes in Volcano seismicity and Armand Vervaeck. Please feel free to tell us about new or changed activity if we haven't written about it. -

Image courtesy seismo.berkeleley.edu - an Glacial flood during an eruption below the Vatnajokull at the end of September 1996

Special Iceland  Glacial Flood update 25/08 - 16:11 UTC - Vatnajökull
Earlier today a ice mass has melted due to thermal activity below the glacier of the Vatnajökull.
The origin of the melting was the Skaftárketill cauldron, an hydro-thermal area inside Hamarinn volcano
The glacial flash flood is currently going down the Skafta river towards the sea. Civil Defence Iceland reports that the flash food (bigger flow of water probably containing also ice and some toxic gases) is not really dangerous if people are staying away from the river bed.
The more important flow will normally arrive in sparsely populated areas later today, during the night or tomorrow morning.
An airplane overflying the glacier has confirmed the Jökulhlaup (Icelandic for Glacial Flood).
Jökulhlaups are a common feature in Iceland with so many volcanoes covered by ice. A Jökulhlaup does not necessarily mean an upcoming eruption but can be a step towards one. Not in this case though. At least it means that the volcano seismicity or temperature has been more active than before.
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.
Road 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.

Update 22:30 UTC :
The video below shows an overflight during the morning hours. The steaming activity can well be seen

Earthquake activity Vatnajökull glacier - Image courtesy Iceland Met Office

Seismic glacier activity at Vatnajökull glacier - Image courtesy vedur.is


August 23-24, 2012 volcano activity

Mount Tongariro volcano (New Zealand) showed some seismicity earlier today (see seismogram below). The activity can only be seen in Oturere and West Tongariro seismograms (close to the Te Maari craters). Below also one of the rara clear view images of Mt. Tongariro with a strongly steaming vent. N report from GNS science about the seismicity however.  The Park service has announced that the trekking trails at Mount Tongariro would be reopened. A 3 km hazard and risk zone will remain in place for some time and might be further reduced once new information of the gas and ash composition is known.

Mt. Tongariro activity zone on one of these few clear moments since August 6 - Image courtesy Geonet and GNS Science

According to INGEOMINAS, the Observatorio Vulcanológico and Sismológico de Popayán reported that during 8-14 August seismic activity at Sotará increased. The seismic network recorded 110 magnitude 0.2-1.6 events mainly located in an area 0.1-5 km NE of the peak, at depths of 2-6 km. Inflation was detected in the NE area, coincident with the zone of increased seismicity. Web-camera views showed no morphological changes. The Alert Level was raised to III (Yellow; "changes in the behavior of volcanic activity"), or the second lowest level. (Smithsonian Institute)

KVERT reported moderate seismic activity from Karymsky during 10-20 August. Satellite imagery showed a weak thermal anomaly on the volcano during 10-13, 15, and 18-20 August. The Aviation Color Code remained at Orange.

KVERT reported that during 10-18 August weak seismic activity was detected at Shiveluch. Observers noted gas-and-steam activity during 15-17 August; weather conditions prevented observations of the volcano on the other days. Satellite imagery showed a thermal anomaly on the lava dome during 10, 12-13, and 18-19 August. Seismic activity increased to moderate levels and hot avalanches were observed during 19-20 August. The Aviation Color Code remained at Orange.

Insivumeh reports 2 moderate explosions at Santiaguito (Santa Maria), Guatemala. The other Guatemala volcano, Fuego sends a white plume approx. 50 meter in the air and grumbles every 1 to 3 minutes. See also seismograms from both volcanoes.

Activity observed by satellites
VAAC reports still the same volcanoes which can be dangerous for aviation ; Sakurajima, Batu Tara and a very active Tungurahua

SO2 satellite imagery shows SO2 clouds at the following volcanoes : Etna, Kilauea and Nevado del Ruiz. Clouds of a number of other volcanoes are not defined enough to be sure.

A smoking Nevado del Ruiz yesterday - image courtesy Ingeominas Colombia

Interesting articles

Hawaii Volcanoes Lodge Company re-opens part of the historic hotel
Shuttered for the past two years, a historic hotel overlooking the Big Island of Hawaii's dramatic Kilauea caldera has reopened for daytrippers and campers in popular Hawaii Volcanoes National Park.
The 32-room Volcano House, listed on the National Register of Historic Places, started out as a grass shack in 1824 and has housed such notable guests as Franklin D. Roosevelt and Mark Twain (who wrote, in 1866, that "the surprise of finding a good hotel at such an outlandish spot startled me, considerably more than the volcano did.") $$$ Read more ...