Signs that a eruption in Grímsfjall volcano might be close (?)

Source

Over the past two weeks there have been signs appearing that a eruption might be close in Grímsfjall volcano. But a GPS station named Skrokkalda. This GPS station has started to move north, but this indicates that inflation has started in Grímsfjall volcano at full power. This did also happen at the same GPS station in 2004 before the eruption in Grímsfjall volcano that same year. But it is debated if this movement was created by ice or by a dike intrusion in Grímsfjall volcano. It is my just my personal opinion on this movement that takes place at the GPS station.

Normally I am the first to slap down the doom-mongers when another Icelandic volcano starts making sign BUT this is Jon Friman's blog and believe me if he says that it needs to be watched, it needs to be watched.

This is the GSP for the area however just one caution I would add is that this plot is only showing to Julian date 95 and we are on 342 now so I am hoping that he has this wrong!

Correction: I was reading this wrong as the year is divided into 100 so this IS a current plot and this is NOT a false alarm

I hope I am not crying wolf so please forgive me if this turns out to be the case.

Just wanted to add that the wording 'a eruption' is as per the title and thus per ATS T & C. It should of course be 'an eruption' but I am bound by the rules unless the mods would like to change it!!!

reply to post by PuterMan


I usually don't pay attention to these threads UNLESS you are posting it! I know you are the go to guy on this stuff.


Thanks for sharing! I will watch this one

I have to say that the tremor plot for if does not look to me to be a problem.



I have left a message for Jon Friman to see if I can find out more.

OK, GFUM to the same date is showing nothing. I am wondering what has happened here - I think this might be a false alarm (Update: This is NOT a false alarm. See post below)

Newsflash

PuterMan was wrong. This is the reply I got.

Nope, you are getting it wrong. They divide the year from 0-100, so 2010.50 means the day, when half of the year is over. This is a silly unit in my eyes.

It certainly is a daft way of doing this, but this is a really useful piece of information since I had always thought these things seemed out of date. It seems they are not!

That means......

This is NOT a false alarm.

Please forgive my ignorance on this subject but I have two questions:

1) Is this the volcano that is situated underneath the glacier that was rumored to be acting up a few weeks ago?
2) What are the implications of this volcano erupting? (meaning is it a large dangerous volcano, etc?)


Cheers!

reply to post by rogerstigers


Yes this is the volcano that produced a jokulhlaup (rush of water) a couple of weeks ago. It was not a rumour by the way as there was some activity but this particular kind does happen every 5 years or so. The activity now is different in that a station North of the volcano has suddenly moved northwards. As Jon Friman said:

This GPS station has started to move north, but this indicates that inflation has started in Grímsfjall volcano at full power.

The names are all very confusing but this is what we more commonly refer to as Grimsvotn and it is under the Vatnajokull icecap.

A full eruption from Grimsvotn is not likely to be so disruptive as Eyjafjallajokull unless the eruption bursts through the icecap which may cause a phreatomagmatic eruption because of water contacting the hot magma, which is more explosive than an eruption under the icecap.

Grímsvötn, Iceland's most frequently active volcano in historical time, lies largely beneath the vast Vatnajökull icecap. The caldera lake is covered by a 200-m-thick ice shelf, and only the southern rim of the 6 x 8 km caldera is exposed. The geothermal area in the caldera causes frequent jökulhlaups (glacier outburst floods) when melting raises the water level high enough to lift its ice dam. Long NE-SW-trending fissure systems extend from the central volcano. The most prominent of these is the noted Laki (Skaftar) fissure, which extends to the SW and produced the world's largest known historical lava flow during an eruption in 1783.

Source: Smithsonian

Note that this system is associated with Laki and actually is in the same system as Katla.

so

2) What are the implications of this volcano erupting? (meaning is it a large dangerous volcano, etc?)

Potentially YES




Edit: A little bit more info on Grimsvotn from an Icelandic site

reply to post by PuterMan


Hey there Puterman,

I have the upmost respect for you on all things volcanic so I shall be watching this space.

One question are there any webcams in the area that we can view ?

Either way thanks for the heads-up

Woody

hey ill keep an eye on this too as much as im able.

s n f for you.
as to crying wolf your better at this stuff then i am ,

reply to post by woodwytch


Unfortunately there are no cams on Grimsvotn that I am aware of.

It is a bit remote and even the GPS system has to have heaters to keep it defrosted.

I guess if anything was to happen they would probably turn the Katla cam to point at it.

reply to post by PuterMan



I have to admit that like others, there are few on this site that I take notice of about these things, but you are one of the few I do

thanks for all the information

Originally posted by PuterMan
reply to post by woodwytch

 

Unfortunately there are no cams on Grimsvotn that I am aware of.

It is a bit remote and even the GPS system has to have heaters to keep it defrosted.

I guess if anything was to happen they would probably turn the Katla cam to point at it.

Ok, thanks for the speedy reply and I shall just keep checking the thread to see what's happening.

Woody

Things are looking very quiet on Grimsvotn. This may not be good, on the other hand it may mean nothing. There has been no new quake activity for three days now.

[atsimg]http://files.abovetopsecret.com/images/member/d5fcffd9121e.gif[/atsimg]

Plenty going on at Askja however!

Hi Puterman, can you clarify what is meant by the gps moving north and what the implications are. Is it the glacier moving?

reply to post by Mez353


Hi Mez, yes basically since that station (SKRO) is on the same side of the fault as REYK which is the datum station it means that the movement is being caused by inflation of the chamber (presumably) at the side of the mountain. It is not the glacier that is moving.

[atsimg]http://files.abovetopsecret.com/images/member/178c088e5572.png[/atsimg]

The movement is actually North East, but the Northerly component was fairly fast. Fast inflations are often a sign of an imminent eruption ( we are talking about volcanoes here )

On the other hand of course it may just deflate again.

Excellent info, and informative,it looks like you know your volcanoes. I'll keep an eye on this. Flag

Deadly quiet again today folks. Not ONE SINGLE earthquake in the past 48 hours or more actually.

This is not good. Whilst it is popping and cracking the stress is being released. No movement may indicate a build up of stress that will pop with a big one, which may event trigger something.

I have updated the animated map here to 15:00 UTC today.

This may not be related but it is the same at Myrdalsjokull. Not one single quake in the Katla/Eyja area since the last one went off the map on the seventh, so that is actually none since the sixth.

[atsimg]http://files.abovetopsecret.com/images/member/5697219a835f.png[/atsimg]

As I did look at Iceland fair
I saw a quake that was not there
It was not there again today
I wish that quake would go away.

Deathly quiet still at this time (02:00 UTC) on both Vatnajokull / Grimsfjall and Katla / Eyja / Myrdalsjokull.

Let us just hope it is because the ice is getting heavier again and the rebound has stopped.

reply to post by PuterMan


Nice poem! Did you make that up yourself?

I gave you S&F for this thread.. I am watching :-)

The 'silence' in these parts is almost eerie, even though other parts of the country are making up for it, i cant help but think we're witnessing the calm before the storm.

Lets just hope it isnt Katla that breaks the silence

reply to post by PuterMan


The lack of the usual quakes is quiet unsettling - - really - not to mention the dead silence!! At first we had flooding then the flooding stopped, so we had some heat underneath the glacier then it stopped. - Now - we have uplift and no quakes - anywhere in the area = Massive pressure building - in the whole area - the question really is - which area has the weakest point and where will it blow?

Trying to work this out in my brain again (kinda hard at the moment got the dreaded flu). anyway - I wonder what the Icelandic specialist are thinking right now!?!

AND Puterman - I just love your special bowing buy (among may other things) - how you do that? :-)