Volcano Watch 2014

a reply to: TrueAmerican

perhaps bardar issent an normal strato volcano as st hellens.. and takes it moore and heavier than 5.6 to outburst..

if so..than it would be an very big one if it goes... VEI 6 ore 7 ?

originally posted by: ressiv
a reply to: TrueAmerican

perhaps bardar issent an normal strato volcano as st hellens.. and takes it moore and heavier than 5.6 to outburst..

if so..than it would be an very big one if it goes... VEI 6 ore 7 ?

so ur saying that Bardabunga is relieving pressure from Mount St. Helens,,
but not enough?

a reply to: TrueAmerican

I think you may be right.

How about this scenerio, taken from one of my cross sections, 20/09/2014, data from IMO.

click image for larger (clearer) version, opens in new tab (might be easier to follow if readers open the graph in the other tab and read the text below side by side with the other tab, this is done by right clicking "Move to New Window" (in Firefox))
Firstly looking at Latitude 64.60 to 64.69 (under Bardarbunga cone)
quakes at 3km show the base of the caldera floor/plug/cork and top of the chamber.
quakes at 4-6km show the tapered sides of the lava chamber.
quakes at 5-km show the base of the lava caldera chamber (floor).
quakes at 8km (incl the orange M5) at Lat 64.59 show where the lava has burst through the caldera walls.

follow the quakes down Lat 64.67 to Lat 64.79 shows the dike under Dyngjujokull glacier 8-13km down.
Then the quakes rise again Lat 64.75 to Lat 64.82 from 15km to 1km showing the lava erupting at the Holuhraun lava field fissure.
So the lava bursts out at Lat 64.59 on the 16th Aug and finds a weakness in the crust towards Holuhraun under the Vatnajokull glacier, eventually meeting resistance at Lat 64.81 where it bursts back up through the crust.
As time goes on the lava is drained from the chamber and the plug begins to collapse, also putting more pressure on the lava to squeeze out along the dike and release at the fissure
If the plug is 3km thick then this would exert tremendous pressure as to moves downwards. The quakes we are seeing in the cross section at the plug and chamber are from the plug scraping down the insides of the cone
The weight of the ice in the caldera ( at 800m thick) may just add to the downward pressure.
The quakes at 100-300 metres (along the top axis line on the graph) are likely ice quakes, as the 800 metre ice cap changes shape to follow the collapsing caldera plug.
No doubt the chamber will empty over time and the caldera floor will be a lot deeper than it was at the start.
The only way I see the Caldera erupting is if something happens at the Holuhraun lava field fissure to stop the release of lava there.



However if depths are taken from sea level, Bardarbunga cone is 2km high above 0km on the graph and the ice cap is 800m thick inside the Caldera, the upper floor of the Caldera is/was 1.2km above the shallowest quake at 0.1km.
If they are taken from ground surface level then my scenerio stacks up


just checked on IMO, the depths are;
" Columns 5 and 6 approximate the focal depth (the distance from the hypocenter to the epicentre)"
according to USGS Glossary
hypocentre is "the point within the earth where an earthquake rupture starts. The epicenter is the point directly above it at the surface of the Earth"
epicentre is " the point on the earth's surface vertically above the hypocenter (or focus)"

so the IMO quake depth measurements (at the Bardarbunga cone in particular) are indeed taken from the surface, so the 0.1 to 0.3km depths are in fact 2km minus 0.1-0.3 equaling a depth of 1.7km-1.9km above sea level, so in fact inside the cone itself, not below it. so any measurements between 0 and 2km are inside the cone.

a reply to: muzzy

are there any natural rivers near by??
u know liquids and there "want" too flow down hill,,which are were rivers are formed.

not Molten Lava rivers,, the other kind.

a reply to: muzzy

and isnt parts of Hawaii being evacuated due to Molten Lava, flow?

a reply to: BobAthome

and a village in the Philipiennes,,lava flow as well??

a reply to: BobAthome

yeah, the one that the current lava field is blocking at the base of Vadalda (where the web cameras are at)
map here, zoom in a half dozen notches then click on Atlaskort from the drop down list top right corner for topo detail and names of stuff
river is called Jokulsa a Fjollum, it comes from out under the Dyngjujokull glacier

web cams are off line for me

a reply to: muzzy

Excellent observations, backed by empirical data.

Yeah, at this point I can't see there being much, if any, eruption at all out of the Barda caldera. Even if the plug collapses all the way down. I mean we have exposed rock at the caldera rim, above the ice, and with the plug slipping, that means any steam created under there would most certainly by now have found an outlet along the plug walls out to the surface. But there is nothing- and that seems to indicate a lack of hot magma below the plug.

That, combined with the fact that chemical analysis has now shown the magma originating as deep-source magma from below 10km down, and me thinks this is something else going on. Like perhaps the mid Atlantic ridge (MAR) separating and splitting the Barda caldera in two, right down the middle. It straddles the fault. MAR separates, throws up some deep magma as usual to replace, and Barda says "nuh uh, I'm done, cooled and solidified." MAR diverts magma flow to weakest points, and the fissure is it.

So muzzy, two things:
1) You might remember that magma isn't lava until it reaches the surface, and

2) Any guesses on the quake magnitude if the cork drops all at once? I don't think it will, because there is obviously something stopping it from doing so, perhaps a layer of partially cooled and hardened magma. But if it does, my guess would be 7+.

Guys, if you're still around, what are these long signatures on STAR at Rainier? In particular, the event at 19:56 UTC.
The frequency on the PNSN spectros looks fairly low.
PNSN spectro for Rainier stations

The ice skidding? They almost look like the elusive "tornillos" on the seismograms.


UW.STAR.EHZ

Same station, but stretched out

Also show on Camp Schurman. Muir station just looks screwy.

Strange nothing from Mount Etna,,

gone silent,,??

originally posted by: BobAthome
a reply to: BobAthome

and a village in the Philipiennes,,lava flow as well??

yeah that wold be Mayon volcano.

LEGAZPI CITY, Philippines—Volcanic activities have slowed down on Mt. Mayon but the possibility of a hazardous eruption remained, according to the Philippine Institute of Volcanology and Seismology (Phivolcs).
Despite earlier fears that Tropical Storm “Mario” would loosen lahar flow from the volcano, an official from the Albay Public Safety and Emergency Management Office (Apsemo) said no such flow occurred in Barangay Maipon in Guinobatan, Albay province.
Eduardo Laguerta, Phivolcs resident volcanologist at the Lignon Hill observatory here, said seismic networks on Friday showed there were 22 volcanic quakes and 70 rockfalls, much less than Thursday’s 142 volcanic quakes and 251 rockfalls.
The volcanologist said the number of volcanic quakes and rockfalls was an indicator of magma movement and the slow extrusion of magma on Friday indicated “a lessening of Mayon’s activity.” Despite that, the possibility of an imminent eruption remained, he added.
“In the history of Mayon, once the lava dome has been noted at the surface, [the volcano] will erupt,’ Laguerta said.
An updated report from the National Disaster Risk Reduction and Management Council (NDRRMC) showed that at least 6,766 families, or 27,755 people, had been evacuated to 27 evacuation centers as of Friday, as volcanic earthquakes and rockfalls from Mayon continued over the last 24 hours.

Permanent danger zone
The evacuated families came from Camalig, Guinobatan, Daraga and Malilipot towns, and Ligao and Tabaco cities, all within the 6-kilometer permanent danger zone (PDZ), according to NDRRMC Executive Director Alexander Pama.
The update also quoted the Department of Social Welfare and Development (DSWD) as saying it had provided evacuees with P6,670,508.93 worth of family food packs, assorted food items and nonfood items, and pre-identified 2,142 evacuation centers in Camarines Sur, Camarines Norte, Albay, Catanduanes, Sorsogon and Masbate provinces.
Phivolcs raised alert Level 3 over Mayon on Monday and warned of a dangerous eruption within weeks after it noted magma rising to the top of the volcano and “rolling incandescent rockfall” on its slopes.

a reply to: Olivine

Maybe a Back Bear snorring too close to the mic.

any stuff in Caves??

its the season, it is wilderness,,

a reply to: generik

hopefully just a little back pressue,, from.,,Hawaii or Bardabunga,, unless Tonga might relieve a little,,

originally posted by: Olivine
Guys, if you're still around, what are these long signatures on STAR at Rainier? In particular, the event at 19:56 UTC.
The frequency on the PNSN spectros looks fairly low.
PNSN spectro for Rainier stations

The ice skidding? They almost look like the elusive "tornillos" on the seismograms.

UW.STAR.EHZ

Same station, but stretched out

Also show on Camp Schurman. Muir station just looks screwy.

Yes, I just noticed these in live spectro, that are going on right now at Rainier. They APPEAR to be some kind of long period events- but perhaps we should wait until the PNSN makes a call on them. Post it to their FB page and ask... They are appearing at all the Rainier stations, btw. *gulp*

Yes, appears to be a seismicity increase all of a sudden at Ranier. Could be ice quakes (oh no, not THAT discussion...again!)

Volcano Activity in Costa Rica on Sunday, 21 September, 2014


The water temperature has increased significantly by 15 deg C., compared to measurements made in 2013.

so anyone want too do the math,,i takes one btu of heat to raise,,etc,,,

should be able to tell the Energy released.

a reply to: TrueAmerican

It does seem to be a sudden uptick in activity on the big beast.
Someone else is going to have to ask on the PNSN facebook group page--I don't have a facebook account any longer.

ETA: Bad form by me, because it's off topic, but I asked Dr. Malone on their seismo blog. I hope he sees it.
__________________


I just read your Bardarbunga post up above. Interesting thoughts.

Me, I definitely think the evidence shows that rifting is the driver of this event.
But, apparantly Bardy's has at least a small personal magma reserve that is eruptible. The IMO state it has had several subglacial eruptions over the past few weeks. But very small, and apparantly not explosive--or the glacier is so massive it has dampened any obvious signals.

If I had to bet, another fissure opening NE of Bardabunga, under the ice, is the next development. As far as a full blown caldera eruption...I don't see it. Like you, I would have thought that the large number of magnitude 5+ earthquakes would have spawned one already, if it was going to happen.

Or my biologic time frame is too impatient, and Bardarbunga is working on geologic time...

a reply to: TrueAmerican

magma! geez for the life of me I couldn't think of the word!
dementia setting in?

that scenerio is only based on 20/09/2014, I'll check back and see if it stacks up prior, the daily depth graphs need to be compressed in latitude to be able to see. I'll start back at the 16th Aug.
Wet day here I have the time.

Total collapse? Yes I'd say a M7+
depends how far it drops in one go, and based on the slip so far of less than half a metre for a M5.5, it would have to be quite a big drop, say 10-20 metres or more
A bunch of M6's would do it too if it was spread over several hours
There is no precedent for this to happen as far as I know.
Krakatoa in the 1800's?

Looking the current earthquake activity, it seems Bárðarbunga is very close to eruption. The activity and the magnitude of earthquakes has increased rapidly past few days. Most of activity now happens within the caldera.

There was sudden drop in caldera this morning, as you can see here:


You can see caldera drop from this site:
baering.github.io...

a reply to: muzzy

that scenerio is only based on 20/09/2014, I'll check back and see if it stacks up prior, the daily depth graphs need to be compressed in latitude to be able to see. I'll start back at the 16th Aug.
Wet day here I have the time.

Didn't quite get there, kept getting interrupted and losing my place.
Did 23 graphs anyway, back to 27th Aug, but missing Sept 1 and 2.
enough to get the picture though.
I cut out Askja and Herdubreid as I don't think they have any direct connection, beyond the fact all of these are on the North Mid Atlantic Ridge Spreading Rift Fault. As I mentioned way back at the start Herdubreidartogl went nuts last year for a while with no eruption as a result.
Seems this caldera floor level, magma chamber roof and floor level and dike track is only quite obvious in the last couple of days and the 14th Sept.
I might make a animated gif of these when I get a chance, might show something going on that you can't see looking at one day at a time.

Bardarbunga-Dyngjujokull glacier-Holuhraun Latitude Cross Section Graphs