Sunday, August 24, 2014

Mag 6.0 Quake Strikes California's Bay Area

A devastating mag 6.0 quake hit the bay area this morning, injuring as many as 87 people, and cutting power off for thousands. No deaths were reported. FIres in the area did break out, and damage control is underway. As I am currently covering the situation in Iceland, this will be a short blog. However CNN is covering the situation.

Below is the shake map so you can see the intensity of the quake.


Google Earth image with USGS Earthquake overlay.

This is the strongest quake to hit the area since the 1990's. California infrastructure is typically considered to be earthquake safe, however some older houses have not been retrofitted to withstand large quakes. 

UPDATE:

More than 200 people have been confirmed injured, and there are reports of historical buildings damaged, and lots of infrastructure. They are working to restore power, and repair roads, inspect bridges, etc. Thankfully there are no reports of anyone being killed. Gov Jerry Brown declared an emergency, which releases federal funds, so recovery should be as quick as possible.


Monday, August 18, 2014

Iceland's Bárðarbunga Volcano ERUPTS [UPDATED 9/2]

*****UPDATES WILL BE FREQUENT. 3 SEPARATE ERUPTIONS HAVE NOW OCCURRED AT BARDARBUNGA. ONE UNDER THE GLACIER AND 2 FISSURE ERUPTION TO THE NORTH OF THE GLACIER. FISSURE IS CURRENTLY ERUPTING*****

An ongoing volcano-tectonic quake swarm in Bárðarbunga in Iceland has prompted the Icelandic Meteorological Office to raise it's alert status to Yellow, and today, it was raised to Orange. Hundreds of quakes, some above magnitude 3.0 have occurred under the glacier. GPS instrumentation is detecting upward-and-outward movement, suggesting magma dike intrusion, and potentially signaling the beginning of eruptive activity. So far, no visible signs of an eruption have been detected, but given the situation, this can change at any time.


Image from Iceland Met office showing continuous quake swarm on Northern Vatnajökull Glacier

It does look likely at this point an eruption will take place, however it is not certain. Many dike intrusions do not result in an eruption, however the area was last active in 2011, when the Grimsvötn volcano, under the same glacier, erupted. Given the amount of ice in the area, if an eruption were to occur, it would likely disrupt air travel as the eruptions of Grimsvötn in 2011, and Eyjafjallajökull in 2010 did.

Aside from a suspected small eruption from Katla volcano, no eruptions have taken place since 2011 in Iceland. Some volcanologists suspected the island was due for some action, and it appears to be here.

Web cams are being set up, according to Jon Frimann's blog. If eruptive activity does end up taking place, I'm assuming the world will probably be treated to a live feed, which will be interesting. The quakes have also seemed to possibly spur some activity in Kverkfjöll volcano, West of Bárðarbunga, with a couple mag >3.0 quakes striking at shallow depths there as well.


Google Earth image of the Vatnajökull ice glacier and associated volcanoes.

This volcanic system is dangerous, and has a long history of creating some misery for Iceland and Europe. The Grimsvötn system and associate Laki fissure system was responsible for one of the largest basalt floods in human history, killing off one fifth of the population of Iceland during the 1700's. Bárðarbunga volcano is related to this system, although it is a different eruptive center. North of Bárðarbunga is a large fissure field, very similar to Laki. 

I will post updates to this blog as further developments unfold. Stay tuned...


*****UPDATE 8/18/2014 @ 2:10pm PST*****

IMO (Iceland Meteorological office) has now confirmed magma movement beneath Bárðarbunga, and is now enforcing a no-fly zone around the volcano. Although no eruption has yet taken place, it now appears semi-likely that this will occur, possibly within the next couple days or weeks.

The pattern of rapid inflation and seismicity is reminiscent of the buildup to the eruption of Eyjafjallajökull in 2010, where rapid inflation was detected by GPS instruments. At this point, it would be a pretty good guess as to say the volcano is priming for eruption. Airline companies would do well to plan accordingly in Europe, and anywhere else with connecting flights. After the eruption of Eyjafjallajökull, airplanes in many countries have been outfitted with ash-detection equipment, and are better equipped to avoid most volcanic ash clouds should they encounter them.

Harmonic tremor is consistently increasing, which is a sign magma is on the move. Earthquake frequency has remained steady, and GPS continues to record inflation.

Get ready!

*****UPDATE 8/19/2014 @ 7:20am PST*****



The earthquake swarm continues with no signs of letting up. There have been no pauses in the frequency of the quakes, and harmonic tremor is still strong. IMO is still reporting no surface activity, but this can change at any time. Harmonic tremor and rock-fracture quakes indicate magma movement, and along with GPS signals it is a safe bet magma is on its way to the surface. If or when it breaks through is too soon to say. As magma must travel many miles from the plume, through rock fractures and fissure systems, and eventually through the ice to the surface, it could be a while. The strongest quake so far in the system has been a ~4.5 quake centered in the subglacial caldera of Bárðarbunga. Many quakes have had greater than a mag 3.0. Most are around 1.5-2.9.

A (poorly translated... thanks Google) statement from IMO this morning is quoted (badly) here:

"Seismicity around Bárðarbunga is still high. Easing around midnight, added back up of 4 and again slightly decreased. The activity goes said forward in waves. The largest earthquakes occurred under the morning but they were all under 3 in size. Activity is largely confined to the eastern Bárðarbunga has shifted slightly to the northeast."

(Please excuse the poor translation, as Google Chrome's translator isn't quite there yet, but you get the idea).

A webcam was installed to monitor the volcano, and can be viewed here.

*****UPDATE 8/20/2014 @ 7:22am PST*****

The quake swarm continues at Bárðarbunga. This morning has so far seen a slight uptick in intensity, with two mag 3.0 quakes recorded in the last 24 hours, and higher magnitude quakes on average than yesterday. Numerous (and un-countable) quakes are still being recorded at intense frequency. GPS continues to show NE motion and uplift of the mountain, indicating magma dike intrusion is still taking place. NO surface activity has yet been detected. Kverkfjöll volcano lies directly east of the Bárðarbunga fissure system, and it is possible dike intrusion could ALSO disrupt this volcano... it is unknown what could happen if their magma chambers meet... Europe is starting to get nervous, but airlines are confident their ash-detectors will help avoid travel chaos (we shall see!), and avert the same sort of log jam that Eyjafjallajökull created in 2010, and Grimsvötn (Grimsnes) in 2011. Keep your eyes on that webcam. I would guess we should start seeing something in the next week or so if this keeps up...

*****UPDATE 8/20/2014 @ 9:16am PST*****

According to the Wall Street Journal, "Iceland's civil protection authority is evacuating people from the area surrounding the island country's Bárðarbunga volcano as earth tremors raise fears of an impending eruption."

At this time, the quakes are occurring at around 5-12KM below the surface and have not yet occurred at shallower depths. What is most likely occurring is that magma is 'plateaued' and slowly filling the magma chamber. If we start seeing quakes move upwards to depths less than 5km, it becomes more likely that rapid ascension of magma may occur. Rock-fracture quake signals, and long-period events would be a good indicator of this happening. Harmonic tremor is still quite strong, so we do know magma is being primed. When it might burst upwards is a good question without a good answer.

*****UPDATE 8/20/2014 @ 10:40pm PST*****

According to volcano blogger Jon Frimann, he has begun to record some long period quakes at this time,a s I previously predicted would happen if the volcano continued to inject magma. This means that rock fractures are occurring, and the lava 'sill' or 'plateau' where the magma is accumulating is under immense pressure, and magma is trying to find a way to the surface. Long period (LP) quakes typically do indicate an eruption is imminent... however the quakes are still at the previous depths, and it does not appear to be rising just yet.

More importantly, these quakes are now occurring within the caldera, which has a 700 meter ice sheet covering the massive crater. Should lava erupt and come into contact with the ice, this would create a very large explosion, along with a very significant amount of ash fall/tephra. This situation would make things a bit miserable for Iceland, and definitely create an aviation hazard. However, if the eruption of Eyjafjallajökull is any guide, an eruption could also be an enormous tourist boon as well. Tourism flourished during the Eyja eruption, and sparked a lot of interest in travel to the island nation. Since there are no significant populations near the volcano, it could turn out to be yet another interest-generating event. If the eruption is large and dangerous (as the area is known to be with the numerous fissure volcanoes, including the infamous Laki flow), it might hurt more than help. Time will tell!

*****UPDATE 8/20/2014 @ 11:09am PST*****

Another larger mag 3.2 quake struck, adding to three strong-ish quakes today. 


Image from Iceland Meteorological Office.

LP quakes continue, GPS deformation is steadily increasing.


University of Iceland GPS data shows extreme deformation in a NE direction.

*****UPDATE 8/20/2014 @ 1:10pm*****

You can monitor quakes at Bárðarbunga in 3D now. This 3D diagram allows you to see depth, and is fed by real-time data. Pretty cool. A 24 year old university student tied in this 3D application to several sources to get the information into a nice 3D graph that you can manipulate and re-position. 


Image from http://baering.github.io/ 

*****UPDATE 8/20/2014 @ 2:41pm*****
The quake swarm seems to be lowering in magnitude, but not frequency at this time. Last couple of hours the majority of quakes have been under 2.0. This means exactly nothing, but it is interesting to watch the patterns... it could also potentially mean (and this IS speculation) that the chamber is full and magma is now pressurizing. IF this is the case, we should expect a lull in quake activity, an increase in tremor, and start seeing more LP events taking place. Hour by hour, more info is generated from instruments, so this is going to be a very frequently updated post.


*****UPDATE 8/20/2014 @ 8:38pm PST*****

The quake swarm at Bárðarbunga has generated 2 more 3.0 or greater quakes. Seismicity remains around where it was, pretty stable at mostly >2.0 quakes, with the exception of the two larger ones. Surface conditions remain unchanged. Harmonic tremor remains very elevated, suggesting that magma intrusion from the mantle plume is continuing. This could end up being a highly energetic eruption.

*****UPDATE 8/21/2014 @ 7:03am PST*****

The swarm at Bárðarbunga continues, and has added some larger quakes this morning, with a 4.0, 3.8, 3.5, and 2.9. These quakes are some of the largest in the swarm so far, and are centered on the main caldera (bad news), and the NE fissure system. As previously mentioned, an eruptive event within the caldera would be... not so good. The caldera is covered by over 700M of solid ice, which, if it comes into contact with fast moving magma would mean a highly explosive eruption, followed by jökullhlaups (glacier outburst floods), which will flood in many directions, according to some analysis.

IMO has released some new reports on the recent history of Bárðarbunga and the Vatnajökull glacier area which has some good information. Quake activity and GPS displacement appears to have started some time in 2013, culminating in the current situation. As is typically the case with many Icelandic volcanoes, which are some of the best studied in the world, they do tend to give advanced indications of impending activity.

It is still a possibility that an eruption at Bárðarbunga will disturb other volcanoes in the area, such as the Grimsvötn volcano, or the Loki-Fögrufjöll volcano system, which would definitely change the outlook for Iceland, air travel, and have some big ramifications. Let's hope this does NOT happen, it is certainly one of those unlikely worst-case-scenario situations.

In any case, I expect activity will be high today, with more large quakes, and the now-typical background seismicity. Harmonic tremor is still high, and stable, which means magma continues to prime the chamber. Yikes.


Image from Iceland Met Office with new larger quakes indicated in bottom ticker.

Note in the above image, 4 or the largest quakes appear to be under the main caldera area of Bárðarbunga. One larger quake can be seen in the fissure swarm area.


Clear day in Iceland today, image from webcam at http://www.livefromiceland.is/webcams/bardarbunga

*****UPDATE 8/21/2014 @ 8:23am*****

This could be nothing, but I think it's worth mentioning, that earthquakes are now occurring in a smaller neighboring volcano known as Tungnafellsjökull, which has no record of historical eruptions. You can see the quakes below, which I was able to 'isolate' from the ones at the Bárðarbunga swarm. One of them is a mag 2.5, and these began occurring within the last couple of hours. It is possible that pressure from the ongoing dike intrusion at Bárðarbunga is disrupting Tungnafellsjökull. Whether this is structural adjustments, or a 'tooth paste squeeze' on some crystal mush is anyone's guess. But I'm keeping my eye on it...


Image from Iceland Met Office, showing some mag 2.0> quakes below the summit of  Tungnafellsjökull

The location of the quakes, and their magnitudes is a bit odd, given the volcano is so old. It is certainly not unheard of for previously dormant or presumably extinct volcanoes to reactivate given the right circumstances. No eruptions for the past 10,000 (Holocene) have been documented at this volcano, so the quakes are a bit surprising.

Smithsonian GVP characterizes the volcano here:

"The Tungnafellsjökull central volcano, located immediately NW of the massive Vatnajökull icecap, contains two calderas. One is largely filled by the Tungnafellsjökull glacier, and the other ice-free caldera located to the SE contains Pleistocene rhyolitic lavas. The 1535-m-high Tungnafellsjökull volcano is largely of Pleistocene age, but postglacial flank fissures on the NE side have produced young basalts. The Hágöngur central volcano to the SW is part of the Tungnafellsjökull volcanic system."

*****UPDATE 8/21/2014 @ 12:38PM PST*****

Add another inter-caldera quake at 3.5 magnitude in the last hour. While the average magnitudes of quakes is a bit lower than yesterday, the larger quakes are more numerous.

*****BREAKING UPDATE*****

According to blogger Jon Frimann:

"There are now clues that Bárðarbunga volcano caldera is getting lower. While there are no signs of imminent collapse such event might happen since this process has started. This explains the earthquake the activity in the caldera, that has been taking place for the past 48 hours. What this means in terms of an eruption I do not know, what I do know is that this type of event if it happens are never small and the following eruption might be huge. This is also going to change the landscape in Vatnajökull glacier forever (that is common thing in Iceland during an eruption cycles).

There has also formed a 25 km long dyke trench in the crust that goes north-east at the moment. There are clues that it might be getting wider at this moment. It appears to have stopped going north-east for the time being."

If this is true, this could indicate that a subglacial eruption is already under way and is melting the ice, as magma escapes from the crust and begins to melt the ice. The mention of a 25KM long 'dyke trench' is also extremely disconcerting. It does at this time appear that Iceland will potentially experience a very large eruption. I am keeping my eyes on the webcam.

*****UPDATE 8/21/2014 @ 5:45pm PST*****

A much stronger 4.6 quake struck the caldera within the last hour. This is now the strongest quake to have hit Bárðarbunga. It is nighttime over there at the moment, so there is nothing on the webcam feed. Any indication of eruption or not will probably come when the sun comes up, however the larger tremors in the caldera are growing in intensity, so it may be a sleepless night for some.


Estimated mag 4.6 quake at Bárðarbunga.

The mag 4.0 that started the swarm was the record holder for the area since the 1996 quake. 4.6 is now the new record in the area, and this just hit the caldera. There is no depth measurement that I'm able to see on this quake yet, as it is so recent. But this may be signaling that things are getting more intense there.

IMO has released this detailed report. They are cautious about saying there will be an eruption, but they do go into detail about the magma dyke and what they propose is happening to lower the caldera's magma pressure. 


*****UPDATE 8/22/2014 @ 7:10am PST*****

The quake swarm continues and has added several more >3.0 quakes. The larger quakes are all centered in the Bárðarbunga caldera. There is no sign yet of lava at the surface. The intensity of the swarm seems to be dying down, but that can change at any time. It's nearly impossible to know what's going on under the volcano. I will post more updates as they come. 

*****UPDATE 8/22/2014 @ 1:40pm*****

Not a lot has changed since the last update. A couple more mag >3.0 quakes, again in the caldera region, struck within the last couple hours. Tremor remains highly elevated but appears to be lowering slightly, which means not a lot. 


Image from http://hraun.vedur.is/ja/oroi/dyn.gif showing steadily decreasing tremor.

Tremor still remains quite high, despite its gradual decrease. This is normal. The reason for this is the same effect as opening a bottle of soda pop. Magma from the mantle decompresses into magma chambers and dikes, thereby gradually lowering that pressure from the initial burst. This does not mean magma is not going to keep pumping into the chamber, it just means pressure is equalizing a bit. You can expect this to remain erratic and unpredictable so long as mantle fluids keep up the pressure.

*****UPDATE 8/23/2014 @ 8:42am PST*****


Bárðarbunga Has started erupting according to the Iceland Met Office (IMO). They state:

"It is believed that a small subglacial lava-eruption has begun under the Dyngjujökull glacier. The aviation color code for the Bárðarbunga volcano has been changed from orange to red."


Image grab from the webcam at http://www.livefromiceland.is/webcams/bardarbunga 

The eruption has apparently already been able to break through some ice, as you can see steam and probably some ash emission on the webcam. 

Get ready!

*****UPDATE 8/23/2014 @ 12:12pm PST*****

The subglacial eruption continues. Tremor spiked at the time of the inferred eruption and has since returned to the level before the suspected breakout. Webcam access is spotty at best due to high traffic. IMO is sending out teams to assess the site from the air, and IMO will likely have some more updates later today.

*****UPDATE 8/23/2014 @ 2:12pm PST*****

Looks like the subglacial eruption has stalled for now, according to IMO who released this update:

"Presently there are no signs of ongoing volcanic activity. The aviation color code for the Bárðarbunga volcano remains red as an imminent eruption can not be excluded."

We are still waiting for photos of the area. It is unlikely the event lasted long enough to break through 400M of rock. For now tremor has dropped back to the level it was at this morning, and it seems that the short eruption might have stopped. However this does not mean it is over. The eruption at Fimmvörðuháls between Katla and Eyjafjallajökull was a dike intrusion into that volcanic system that erupted with a short-lived cone building event. Afterward, the main volcano at Eyjafjallajökull erupted with force. If the area at Fimmvörðuháls was covered in thick glacier, the pressure would have been greater. As tremor is still occurring, it is likely this was a small fraction of the magma that erupted to become lava, and is quite possible in this system that fissures will open elsewhere. There is no way to tell where or when, so IMO is keeping the alert level at Red for now.

New activity is somewhat likely to sprout up at different locations. As long as tremor, and quake swarming continues, it is likely this is just a prelude to the main event. Currently tremor is fluctuating up and down, and it looks like this was just the tip of the ice... so to speak. Strong quakes continue to hit the area as well, which could be rock fracture events, meaning magma is still on the move.

GPS data shows the motion towards the N has remained steady, and E motion is still ongoing. 

*****UPDATE 8/24/2014 @ 9:00am PST*****

IMO is now saying that an eruption has not occurred yet, and that no evidence for a subglacial eruption was found. This is still some guesswork, but it is looking unlikely that one has occurred. The seismic swarm however has become a lot more powerful with new record breaking quakes in the area measuring 5.3, 5.1, and 4.8. Many other strong quakes are occurring, and tremor is still very strong. The dike is now measuring anywhere from 30-40km long, and has encountered denser crust. If magma keeps getting injected into the dike, and no outlet is found it is possible an eruption will occur. 

So to recap: An eruption has not occurred yet, however magma is still being pumped into the dike and magma chamber. The magma dike is longer and wider, and will likely rupture if this trend continues. Very strong quakes are now hitting the area, and this is far from over. 


The swarm is less dense, but producing more powerful quakes.

*****UPDATE 8/24/2014 @ 2:22PM PST*****

Another mag 5.3 quake was detected between the caldera and inferred dike zone. This ties the areas record for quake magnitude during this event. It is still highly likely an eruption will take place. However at this time, no activity has been spotted or recorded on instruments, despite previous assertions by IMO that an eruption was under way. A recon mission gathered no evidence for an eruption just yet. 

*****UPDATE 8/25/2014 @ 10:00am PST*****

Another 5.1 quake struck the caldera a couple of minutes ago, and IMO has released the following update.

"Overall assessment from the joint daily status report 250814 of the Icelandic Met Office and the University of Iceland, Institute of Earth Sciences: There are no indications that the intensity of the activity is declining. Currently, three scenarios are considered most likely:
1) The migration of magma could stop, attended by a gradual reduction in seismic activity.
2) The dike could reach the surface of the crust, starting an eruption. In this scenario, it is most likely that the eruption would be near the northern tip of the dike. This would most likely produce an effusive lava eruption with limited explosive, ash-producing activity.
3) An alternate scenario would be the dike reaching the surface where a significant part, or all, of the fissure is beneath the glacier. This would most likely produce a flood in Jökulsá á Fjöllum and perhaps explosive, ash-producing activity. Other scenarios cannot be excluded. For example, an eruption inside the Bárdarbunga caldera is possible but presently considered to be less likely."

*****UPDATE 8/25/2014 @ 7:24pm PST*****

USGS has just detected a mag 5.7 quake within the Bárðarbunga  caldera. So far IMO doesn't seem to have analyzed/agreed with USGS as to the location/magnitude/depth, but if true, and USGS is quite accurate, this would be the biggest quake so far in the series. IMO has chalked up the quakes in the caldera to drainage of the magma chamber into the dike intrusion. This would result in an absence of pressure in the chamber and could be indicative of collapses, however the quakes are getting larger, not smaller, and a mag 5.7 is not a small quake. It is unknown, despite the data and analysis by IMO and USGS what is going on in the caldera. They are making educated guesses with the signals. They are relying on GPS surface data, satellite, flyover, and seismometer data. While all of these instruments are of great use, they do not have xray vision of the magma chambers yet. At this time I expect the magnitude of quakes to increase in strength and frequency. The quakes could very well be foreshocks to another larger event, or they may not. If we start seeing quakes above mag 6.0 I would start getting a little worried. Time will tell. So far there is no indication that magma flowing into the system is slowing down, and there is no indication of where it may pop up. The activity seems to be concentrated at the Northernmost end of the dike. If the magma has nowhere to go, it will likely head upwards as the path of least resistance. I do still believe that an eruption is highly likely in this case, however with glacial weight which could be suppressing an actual eruption, it is anyone's guess. This is after all the largest glacier in Iceland, and it weighs an awful lot. Magma pressure would in fact need to be quite high in order to break through a pressurized and frozen crust. Again, time will tell. I think for now we can expect very high seismic activity, pressure, fractures, and the quakes take their course.

*****UPDTAE 8/26/2014 @ 11:21am PST*****

Not a lot to update at this time. Seismicity is still very high. Quakes are still concentrated at the Northern tip of the magma dike intrusion. A 5.7 magnitude quake did occur under the caldera, and IMO is still saying this is related to reservoir drainage, however I'm beginning to disagree, as the quakes are getting stronger. The Northern tip of the dike intrusion, which lies several miles outside of the glacier, is the inferred location of any future eruption at this time. I agree with this, as the large glacier overhead undoubtedly puts a lot of pressure on the underlying crust, therefore it is logical to assume that the magma will 'seek' a location where the path to the surface offers the least resistance. Time will tell of course. It could still be days or weeks before an eruption happens. It can really happen at any time, but realistically, we're probably looking at weeks. Magma is still flowing IN to the system, and pressure is always increasing. How much it will take to finally burst through is anyone's guess. If current trends continue, we will likely see an effusive fissure eruption, which would be good for air travel as ash would be minimal or nonexistent. The danger for air travel would be if the caldera erupted through the ice, creating fine ash like Grimsvötn, or Eyjafjallajökull. For now, it is the status quo at the volcano. High seismicity, same depths, and no surface activity. The alert level was lowered a couple days ago to Orange, down from Red, when it was thought at the time that a subglacial eruption had occurred. They later determined that no eruption had occurred at all, and the signals they were seeing had another source.


*****UPDATE 8/27/2014 @ 7:15pm PST*****

Looks like maybe there was an eruption under the glacier after all (still not confirmed without a doubt, but it is looking that way). This is getting a bit confusing for some, but apparently IMO made an overflight in the last day or so and saw some ice cauldrons forming in a 6km line. The statement is as follows:

"Scientists from IES and IMO on a flight to Vatnajökull tonight discovered a row of 10-15 m deep cauldrons south of the Bárðarbunga caldera. They form a 6-4 km long line. The cauldrons have been formed as a result of melting, possibly a sub-glacial eruption, uncertain when. Heightened tremor level/volcanic tremor has not been observed on IMO's seismometers at the moment. The new data is being examined."

It's sounding a bit like their instrument data is not coinciding with observations, so perhaps this is a pretty unique event as far as volcanoes in Iceland go.

Quakes continue in the dike area, and larger quakes are going off in the caldera system. IMO still seems convinced that the caldera is draining, not inflating, however I and several others are thinking the large quakes might be something else. 

*****UPDATE 8/28/2014 @ 4:41pm PST*****

The quake swarm continues with no signs of stopping. The dike intrusion is now growing at about 1-2km per day, and has actually started to penetrate the Askja volcanic system to the north. This could be very BAD. Askja is a caldera system, and responsible for one of the largest eruptions in historical time in Iceland, second probably only to Laki. If the magma dike starts to mix with the Askja magma chamber, anything could happen. The area is highly unstable, and Icelands largest landslide in historical time was just recorded there, which created a small tsunami in the caldera lake. Thankfully nobody was there at the time, as it is a popular tourist destination. The area is currently closed. Jon Frimann is reporting that the dike has now caused cracks in the crust to open, and as water flows in, hot springs and fumeroles are starting to pop up. This suggests an extremely shallow magma system, even though the majority of quake activity is occurring in the 3-5km range. This means that phreatic explosions are now possible. If a significant amount of water comes into contact with hot magma, explosive eruptions will occur. This would likely open up an avenue for lava to erupt. This eruption, if it occurs, is likely to be quite large, and diverse. 


Image from IMO, cracks can be seen in the glacier, next to the small sky-blue lake.

*****UPDATE 8/28/2014 @ 10:00pm PST*****

An eruption has begun at the Northern tip of the Dyngjujökull ice glacier. Statement from IMO reads:
"A fissure eruption has started north of Dynjujökull.; An eruption started in Holuhraun north of Dyngjujökull at around 00:02. Seismic tremor was observed on all seismic stations and the web camera installed in the area by Mila has showed some nice pictures of the eruption. It is a small fissure eruption and at 02:40 AM the activity appears to have decreased."

I grabbed a screencap of the webcam at Mila, and highlighted the eruption site. You can now watch the eruption unfold LIVE.




Image form Mila webcam, showing beginnings of fissure eruption at the foot of Dyngjujökull glacier, in the Bárðarbunga  volcanic system.

If lava continues to erupt, the webcam will look spectacular at night.

*****UPDATE 8/29/2014 @ 7:12am PST*****

Last night's fissure eruption left some new lava cooling on the surface, but was not a very long or large amount. More eruptions are probably going to happen, as this wasn't a large amount of eruptive material, and certainly nowhere near the amount that has been injected into the dike/caldera system. A 5.2 magnitude quake struck within the last hour, and seismicity remains high. There was a short dip in seismicity after the eruption which was related to the small pressure release. But it is now clear that the magma has become shallow, and at least last night, it found a way to the surface. So far no explosive eruptions or any threats to flights. Keep your eyes on the webcam!


Aerial image from Icelandic Coast Guard showing cooling lava at the Dyngjujökull fissure.

This link to a Ruv.is article has great video of an overflight of the area as well. 


Image of the lava flow before it cooled down, from Smithsonian GVP's Facebook profile (photographer unknown, possibly from Icelandic Cost Guard)

Due to the ongoing dike intrusion into the Askja volcanic system, and associated disturbances, seismicity, and large quake recently in the caldera, Askja has been moved to Yellow alert status, and is being monitores for activity. At this point, if the dike intrudes into the Askja volcano system, it is unknown what will happen if the dike mixes with Askja's magma chamber. It is possible the mixing of lavas will create a highly explosive eruption. This is similar to eruptions at USA's Mt Hood, where andesitic magma merges with silicic magma, creating a magma cocktail capable of very large explosive eruptions that would generate lots of ash/tephra. It appears from the dike eruption that the lavas being erupted are low in silica (basaltic) and flow like the pahoehoe lavas in Hawaii's Kilauea/Mauna Loa. Askja's eruptions have been mostly phreatic in nature, emitting lots of tephra, but the lavas may be quite different in mineral and gas composition, so anything is possible in this scenario. As of now, the alert level seems to indicate that IMO is actually a bit worried about this occurring, but at the time of this writing, the dike advancement towards the magma chamber of Askja appears to be at a pause... so this may not happen at all.

*****UPDATE 8/31/2014 @ 10:14am PST*****

Another fissure eruption is now underway, along the same fissure line as the previous eruption. Video has been posted to Youtube here: https://www.youtube.com/watch?v=0G3R1QH_AXU





Nighttime sceengrab from Mila cam.

As of about midnight PST (USA West Coast time), the eruption appears to be losing a little bit of the vigor it had during the night, but this could be the result of the fissure concentrating lava through vents that have formed, much ike the Fimmvörduhals fissure eruption at Eyjafjallajökull in 2010. It's tough to tell from the webcam at the moment, but it seems the middle of the fissure is still active, with some activity to the north end. More than likely this fissure will stop erupting soon, at least for a bit. Tremor indicates magma is still flowing into the dike system and caldera area. While IMO isn't saying an eruption at the caldera is likely, large shallow quakes could still portend an eruption. For now, looks like the fissure is at least beginning to lose steam but it has not stopped erupting just yet.

****UPDATE 9/1/2014 @ 7:52pm PST*****

The eruption at Bardarbunga continues with no indication that it is stopping. the eruption is strong, and the lava keeps flowing to the North towards Askja (not near it).

*****UPDATE 9/2/2014 @ 7:25am PST*****

The eruption continues today, however quake numbers have fallen to about 300 a day, down from a max of around 1200 a day. According to IMO, this means that magma inflow has matched lava outflow, which means as much magma is being injected as is ending up as lava on the surface. There are no signs presently that the eruption is going to stop. What this does mean is that pressure inside the system is equalizing, so it is unlikely at this point that a summit eruption would ensue, unless the fissure eruption ends, and magma continues to be injected. For now, this looks like it will remain a Hawaiian style pahoehoe eruption until something changes. about 300-500 cubic meters per second of lava is being emitted. Currently webcams are showing intense fog, so we don't have a great view this morning.










Rare Lava Lake At Shishaldin Volcano

Alaska's Shishaldin volcano has apparently formed a lava lake deep within its summit crater, making it one out of only several active lava lakes on the planet. AVO's current update has the volcano remaining at aviation code 'orange', and eruptive activity has remained stable. AVO states:

"Low-level eruptive activity continues. Sound waves are currently being detected from the direction of Shishaldin on infrasound sensors located on Akutan Island. These signals are consistent with low-level activity at the volcano. No actvity (sp) has been detected in mostly cloudy Satellite images and web camera views are obscured by weather. No significant activity noted in seismic data."


Picture from AVO showing the small lava lake within Shishaldin's summit crater. (Credit Cyrus Read)

Shishaldin volcano is one of Alaska's most active volcanoes. A beautifully symmetrical volcano on Alaska's Unimak Island, far from any human population. The mian danger from this volcano could be unexpected ash emission, which would potentially be harmful to aircraft. However, the presence of a stable lava lake makes this rather unlikely, as gas is easily vented at this time, so large explosions are a bit less likely than say, if a lava dome was forming. In any case, keep your eyes on AVO for future updates and more great photographs. I'll post another update if anything changes. 



Friday, August 8, 2014

Curious Quake Swarm in NW Nevada [UPDATED 8/29]

Nobody at all is reporting on this, although it's no secret either. There is an oddly shallow and very active quake swarm occurring in NW Nevada, about 65 KM ESE of Lakeview, Oregon (as USGS reports it) and it has been going on now for over a week and a half.

The area the quakes are occurring in does not seem to have any significant human population, and appears to be mostly mountainous desert, overlain by igneous rocks of what I'm guessing are older than pliestocene. There isn't a lot of info on the area, much less any geological information I'm able to find.

In any case it appears to be a long series of very shallow quakes ranging in size from <1.0 to greater than 3.5. The area does appear to be on a spreading rift, and probably has a past history of volcanism, but there are no records to confirm this.

As these quakes have ranged in depth from <2km to near surface, I'd say we are looking at a purely teconic event, and nothing related to volcanism. Again, there are no news articles or blogs I'm able to find. Below is a screenshot.


Google Earth Screenshot of location of quake swarm using USGS overlay.

I'm purely writing about this out of curiosity, and want to keep speculation to a bare minimum. I wonder if any USGS people would like to comment on what they suspect this is? It's happened before!

*****UPDATE 8/21/2014*****
Looks like the media and geologists are finally taking notice of this quake swarm. So far, indications are that it is purely tectonic, but they don't know yet. The area has a history of tectonic activity, however this swarm appears to be unprecedented for the region. Here are the few reports I could find on this:

http://www.oregonlive.com/pacific-northwest-news/index.ssf/2014/08/seismologists_are_tracking_swa.html
http://www.rgj.com/story/news/2014/08/19/earthquake-swarm-northwest-nevada-see-map/14301965/

*****UPDATE 8/29/2014*****

The quake swarm in NW Nevada continues, adding a magnitude 3.8, 3.2, and numerous smaller quakes. All are occurring at depths less than 2km, and some (probably not manually reviewed, and auto-detected quakes) are occurring near or at the surface according to the data feed (which is probably not accurate). So far there is no analysis from USGS aside from what has been briefly mentioned in articles. This 'swarm' is interesting at least to me. There are volcanic basalt cliffs in the area, and it does appear to be part of a rift zone. There is little to no human population in the area, and I am wondering if anyone has visited it to gain some visual observations, or install more instrumentation. At this time, it's being reported that this is purely tectonic, and there are no reports of anything to suggest otherwise, however volcanic activity or dike intrusion can't be ruled out given the composition of the surrounding rocks. Something odd is going on up there.

Tuesday, July 22, 2014

New Round Of Warnings For Mt Fuji

Apparently the news media wants to remind you of the dangers posed by Mt Fuji, who's magma chamber has been pressurized to unprecedented levels following 2011's major 9.0 earthquake in Japan. A 6.4, and 5.0 quake followed, centered under Mt Fuji, which has caused some concern for scientists and nearby cities. I reported on this over two years ago, and while not much has changed, it seems that this is back in the headlines again, so I thought I'd set the record straight, lest the news media sends you into a panic.


Mt Fuji seen from Japan.


Here are some basic facts.

Yes, Fuji is under an immense, even record amount, of pressure in its magma chamber. The pressure is currently greater than it was during the 1707 eruption which blasted a massive crater in the SE flank of the mountain. This means that any further disturbances, such as medium to large quakes in the region could fracture rock, and allow for magma and gas to rise, raising the risk of a highly explosive eruption.

This is by no means imminent, as it is impossible to predict quake activity or location. It simply means that Fuji is primed, and large quakes close to the mountain would increase this risk. Right now, no seismicity other than normal background rumblings are occurring. So there is no need at this time to panic.

Japan has been criticized for its lack of disaster planning regarding Fuji, however last year they did release a new evacuation plan in the event of an eruption, which would likely give some warning in the form of increased tremor (long period quakes, rock fracture tremors, etc) and increased gas emissions.

The important thing for scientists, and Japanese residents is to simply remain aware and vigilant of the threat. Japan is still recovering from the aftermath  of the 2011 quake, tsunami, and nuclear meltdown of the Fukushima Daiichi power plant which was damaged by the quake. A massive volcanic eruption from Fuji IS in the future for Japan, it is only a matter of time. That time however is impossible to know. Fuji is capable of depositing significant amounts of ash as far away as Tokyo, so an eruption would have severe consequences for an island already stressed by other disasters.

But again, this is nothing new, and we have known that Fuji is primed for several years now. As I can attest looking at my traffic charts on my own blog, any news about Fuji, one of the worlds most famous volcanoes, is always a click-generator. It doesn't mean you shouldn't pay attention, but don't lose too much sleep over it.

Friday, July 11, 2014

Outburst Flooding From Katla Volcano Iceland [UPDATED 7/16/14]

It appears that Katla Volcano in Iceland, under the Myrdalsjökull ice glacier is experiencing heightened activity. Fellow volcano blogger Jon Frimann has posted that Iceland has raised the alert level to 'uncertain', as glacial outburst floods or 'jökulhlaups' have been occurring, in conjunction with rising conductivity levels in rivers, as well as gaseous hazards being reported.

Katla volcano had a minor eruption following the now-famous eruption of Eyjafjallajökull in 2010.

Current seismicity is concentrated within the Katla caldera underneath the glacier, and no eruptive activity on the surface is yet apparent.

It is too soon to say whether any activity will increase. Other areas in Iceland are showing increased seismicity, including the Askja system, and the Torafjökull volcanic system, however no eruptions have occurred in Iceland since mid 2011 when the last eruption of Grimsnes (Grimsvötn) occurred.

If any updates happen, I'll update this post.

*****UPDATE 7/16/14*****

A larger quake swarm is occurring within the Katla caldera. The largest quake, which occurred yesterday, was magnitude 3.1. While numerous, these small quakes do not represent anything truly immense at this point. It is possible that eruptions might begin at the volcano, but these would likely be small, and probably not energetic enough to break free of the glacier.


(Click to enlarge) Image from en.vedur.is/Iceland Meterological Office showing quake swarm in Katla caldera.


Iceland has lifted the 'uncertain' warning from Katla, however it is possible for jökulhlaups (glacier outburst floods) to occur with little warning. Given the activity, I'd steer clear of the volcano and associated watersheds until things calm down. Hazards include jökulhlaups, gases, and the possibility of explosive eruption (even if unlikely at this point).

I'm keeping my eye on this one for a while. Iceland has had a few years of relative calm (by relative, I mean nothing too explosive... the land there is always seething), which is always a little nervous. Iceland's many volcanoes are always a potential threat, and can erupt with little, or very subtle warning.

Thursday, July 10, 2014

Large Quake Swarm at Long Valley Caldera, CA

After a few months of relative quiet at California's Long Valley Caldera, East of Mammoth Mountain volcano, activity has intensified with hundreds of small and shallow quakes at depths of around 4.7 miles. Many small tremors are occurring below the surface about 1.5 miles north of Yosemite Mammoth Airport. These are small quakes, and likely not able to be felt by anyone not at the epicenters. These quakes are interesting mostly due to the sheer numbers, not the magnitude.

More than likely these are hydrothermal 'spasmodic' quakes, related to liquid movement under the surface, and likely not a result of any serious magma intrusion. If there were a large intrusion of magma, you would expect to see the depths of the quakes change (these are all relatively consistent) to progressively shallower depths. Since this isn't occurring, it is reasonable to assume this is simply normal behavior for Long Valley's large hydrothermal system, rivaled only by Yellowstone in the US.


Image from Google Earth with USGS overlay detailing locations of quakes in Long Valley.

The Long Valley caldera is a so-called 'supervolcano', like Yellowstone, or the Valles Caldera in Mew Mexico. Long Valley was the source of one of the largest eruptions on Earth, approximately 760,000 years ago, which created the voluminous Bishop Tuff, a layer of ash and debris that spans most of the continental US. Like Yellowstone, Long Valley is capable of 'nation ending' eruptions, however this, like Yellowstone, would be extremely unlikely in our lifetimes. 

The last 'serious' activity at Long Valley was a 6.0+ mag quake in the late 70's, which was followed by rapid 'doming' in the center of the caldera. On average this 'resurgent doming' has added several centimeters in height per decade.

It is likely in the future that activity will resume at Long Valley, given the doming, active geothermal system, and persistent seismicity. For now, I wouldn't lose any sleep over this, as it is not only quite common, but completely normal activity. If larger quakes were to 'swarm' in the area, this would be a cause for concern.

*****UPDATE 7/11/14*****

Looks like the swarm is over for now.