Category: GPS data

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General overview of Grímsvötn eruption on 23. May 2011 at 20:33 UTC

This is a general overview of Grímsvötn eruption on 23. May 2011 at 20:33 UTC.

Ash cloud: The ash cloud is still going strong. It is however a bit lower then in first few days. Measurements of the ash plume now says that it is between 5 to 9 km. Because of that it does not appear on the radar at IMO. The ash cloud has now been detected all over Iceland, except for the most western part of Iceland (Westfjod). In the areas closest to the main ash cloud the visibility is from 1 meter and up to 500 meters when it is at it’s best. Ash fall is expected to last for the next few days, or until the crater does not get any water into it to make the ash. The ash cloud is expected to reach Scotland tonight (Rúv, Icelandic). BBC News about cancelled flights due the ash cloud. Farmers live stock has started to die due to the ash cloud. It is unknown how the wild life is doing while the ash cloud covers part of south Iceland. Current output of the Grímsfjall volcano is about 1000 to 2000 tons of ash pr second. It was around 10,000 tons of ash pr second during the first days of the eruption.

Rúv News, Öskufall næstu daga (Icelandic, Rúv.is)

Eruption: Even if the ash cloud is lower now. It appears that the eruption is still going strong. In the evening news at Rúv it was reported that there was a chance the magma that powers this eruption might be from a great depth (more then 20 km). Tremor graphs that are online show and suggest that the eruption is still at full power. The reason why they are at lower noise level is most likely due to fewer explosion in the eruption, as less water is in the crater. When water no longer goes into the crater it turns into lava eruption. There is also an speculation that new fissures might open up in this eruption where there is more glacier cover (evening news on Rúv). But that would mean flash glacier flood and new ash cloud when the eruption would break the glacier covering it. But so far this has not happened and is nothing but a speculation. It would mean earthquake activity when the magma would break the crust, as happened when the eruption did start on 21. May 2011.

GPS data: According to report from IMO and University of Iceland the deflation now has been 50 cm to northwest and has subsided 25 cm. According to the report this about 60% larger then after the eruptions in the year 1998 and in the year 2004.

Web cameras: Grímsvötn Míla web cam is now up and running. It should be possible to see the eruption when an ash cloud is not in the way. But so far that has been the case.

Please note that information here might get outdated really fast and with no warning at all!

Updated at 20:42 UTC.

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Krísuvík volcano starts to inflate at fast rate

There is currently no shortage of volcano news coming from Iceland at this moment. The newest volcano to make the news is the Krísuvík volcano. Small area of Krísuvík volcano have been inflating during the last few months with following micro-earthquakes swarms in the area where the inflation takes place. This process started last year (2009). But then the inflation was 30mm (3 centimeters). But last winter a process of deflation started and lasted until early spring this year (2010). But then it started to inflate again. I am assuming that the current levels of inflation is something similar to the inflation that was seen in the year 2009. The area in question is south-west of Kleifarvatn lake.

The inflation is currently taking place on the depth of 3 to 4 km according to geological scientists. This intrusion of magma is also having effects on geothermal features present in the area. But that makes new hot springs and makes current hot springs more active and warmer, it also changes them and often dramatically. It might also create new hot spring areas where no hot springs where before. This inflation process has been followed by a swarms of micro-earthquakes in the area where the inflation is taking place.

According to the news the Icelandic Met Office has alerted the Icelandic Civil Protection Authorities about the changes in this volcano. Two new GPS stations have also been installed in the area to monitor the inflation that is currently taking place. At current time scientists are not expecting a eruption in the area any time soon. But as history has shown that can change without warning and quickly. The authorities and IMO have increased there surveillance in the area due to this inflation. If a eruption takes place the type is going to be a Hawaiian type of eruption, unless a fissure opens up under water or in the ocean. Last eruption that took place in Krísuvík volcano was in the year 1340.

Icelandic news, in Icelandic. Please use Google Translate (at your own risk)

Grannt fylgst með landrisi við Krýsuvík (Vísir.is)
Telja eldgos ekki í uppsiglingu en ástæða að vakta svæðið vel (Víkurfréttir)

Channel 2 news video (flash) about this activity. In Icelandic.

Updated at 23:52 UTC on the 30th of November 2010. News video added and name error fixed.

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GPS changes in Grímsfjall due to ice on GPS antenna

I did just speak with geologist at Icelandic Met Office and the he told that the recent changes in GPS measurements in Grímsfjöll where not real. But they where created by ice. But now the ice has been cleared of the GPS antenna and the data is now correct.

But the real movement is to the south and Grímsfjall has continued to do that. So Grímsfjall is continues to inflate at relative fast rate and prepares for a eruption as magma flows into the Grímsfjall magma chamber.

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Grímsfjall continues to inflate

I see that many people think that Grímsfjall has started to deflate due to a drop in GPS measurements. But the “Up” part of the GPS measurements have been dropping over the past few days from about 85mm and down to about 65mm today.

As that may be true that the mountain has started to deflate from the top. It is not to say that deflation process has started at Grímsfjall. As the GPS data clearly shows that a inflation process has just moved from the top and to the south. But current GPS measurement clearly show that Grímsfjall is now inflating to the south (15mm today) with minor inflation to the east (about 15mm today). So it is clear that the magma is moving inside the volcano from one location to a other over the past few days. What that means is unclear at the moment. But it appears that the inflation to the south is speeding up at current time. This might get interesting soon in my opinion. Regardless if there is a eruption or not.

Data: ISGPS GFUM
Vatnajökull continued GPS data project from 2004.

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Grímsfjall continues to inflate

According to GPS data from GPS station located on top of Grímsfjall the volcano continues to inflate. Now it is about 80mm and does not seems to go much higher then that for some reason. Since Grímsfjall has stopped to inflate up at the moment it is currently inflating in other directions. The automatic GPS data clearly shows that the inflation is now moving south but is interestingly is holding it east-west movement. I am not clear on why that is the case at the moment.

Data: GFUM ISGPS

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Grímsfjall continues to inflate at fast rate

Over the past two days the GPS station on Grímsfjall has been reporting some interesting data on what is going on inside Grímsfjall. But it appears that Grímsfjall is inflating at really fast speed at the moment. The movement is mostly upwards, as the station is located on the top of the mountain.

Currently the GPS station at Grímsfjall is reporting about 85mm movement upwards and about 5mm movement north (moving south). At last the movement east is about 10mm. But that gives the expansion site close to the GPS station, I would estimate rather rudely about 5 to 10 km from the SIL and GPS location. But it might be closer or longer. This is just a badly educated guess that I am doing here.

It is clear that if Grímsfjall continues to inflate at the same rate and it has been doing for the past few days and weeks it is going to erupt real soon. When is a good question as always.

Data: ISGPS GFUM