Monday, December 29, 2014

Super busy but will post again soon!

To my readers:

Thanks for staying tuned. I recently went through a large job change, and had some family emergencies to take care of, as well as the holidays. I will be resuming posts again shortly.

I have not updated blogs regarding Fogo, Bardarbunga, or the Nevada quake swarm because nothing really has changed, and things continue as they have been.

Fogo and Bardarbunga continue to erupt at this time with no signs of change. Fogo volcano has swallowed up more villages on the volcano floor, including some historic towns over 100 years old. Bardarbunga's lava field is now about 80+ sq km in area, and caldera subsidence slowly continues, although current data isn't available due to equipment loss and weather conditions for Iceland Met Office.

The Nevada quake swarm is still ongoing, and USGS is installing new equipment. Quakes of mag 1.0-4.7 have occurred.

If you're looking for some quick volcano updates for the week, the Smithsonian GVP is a great place for current info at their Weekly Report section.

I'll be back on 'the job' after New Years.

Have a great holiday season everyone!


Sunday, November 23, 2014

Fogo Volcano Erupts


Pico Do Fogo volcano, one of the Cape Verde islands, erupted about 4 hours ago, INVOLCAN's Facebook account reported.

No more information is available quite yet. A Google search turns up no news yet. The posted video showed a small ash plume a few thousand feet (estimated) high. The eruption does not appear to have occurred from the summit, so it could be a cinder cone building event. I will post more updates as they come in.

Fogo volcano last erupted in 1995, with a cone building event on its WSW flank. This event appears to be similar. 

Youtube video of the eruption of Fogo, 2014.

UPDATE: 11/25/2014

You can view footage of the eruption now on INVOLCAN's Facebook page. It appears to be a cone building event with a large lava flow at this time. People were evacuated out of the caldera area, and footage shows what appears to be a large amount of gas. Footage shows what appears to be large lava flows of 'clinker' (also called a'a' lava) destroying some brick buildings, so it does appear there has been some property damage. To my knowledge there have been no injuries or casualties.

Video news (in Portuguese) can be seen here

Youtube video of eruption plume (this is the small light blue area in the center screen)

Youtube video of lava destroying property and advancing.

Friday, November 14, 2014

Curious Quake Swarm in NW Nevada [UPDATED 3/17/2016]

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:

*****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.

*****UPDATE 11/6/2014*****
Surprisingly, this swarm is still active. A 4.7 magnitude quake, and a 4.6 are so far the largest quakes of the resurgent swarm. There is no explanation from USGS other than 'this is probably tectonic'. I tend to agree, as the quakes are extremely shallow, in some cases appearing to be so shallow it reads as '0.0 km depth'. However, the 4.7M quake was at a depth of around 5km, which can indicate some sort of volcanic origin. It's still way to early to tell what's going on, and without comprehensive analysis by USGS or a geologist, I still have no new info to really put forth, other than the swarm has been active now for months, which is certainly unusual. I can find no analysis, GPS charts, or otherwise to give any more details, but I will follow up when any info comes out (I am keeping my eye on this). Stay tuned!

*****UPDATE 11/14/2014*****

The quake swarm continues, with USGS releasing a statement saying they are finally going to be out in the area installing new equipment, which should give us a much better picture about whether this even is simply tectonic 'exfoliation' events, rifting, or perhaps even volcanic (which is highly unlikely, but not impossible). The duration of the swarm is still quite interesting, as it has now been occurring for several months now.

***** UPDATE 11/24/2014*****

Seismologist have indeed installed new equipment, hence the better depth readings. They are working out whether or not this is volcanic or tectonic, as reported in the above link:

"Bill Hammond of the university’s Nevada Geodetic Laboratory said that while some residents wonder if the latest swarm is related to an extinct volcano in the Sheldon wildlife refuge, experts think it stems from the region’s faults. However, conclusively ruling out a volcanic source will require the additional seismic and geodetic measurements closer to the events,"

*****UPDATE 1/19/2015*****

Amazingly this swarm is STILL ongoing with little to no difference in behavior. USGS is still installing new instrumentation in the area, according to the latest info. So far they have not updated their previous statements that this is tectonic in nature. I have no cause to disagree.

*****UPDATE 3/3/2015*****

I know I'm starting to sound like a broken record at this point, but yes, this quake swarm is STILL ongoing. And thus far STILL no concrete answers from USGS other than "This is probably tectonic". Quakes are still at depths ranging from 9km to under 3km, and raning in magnitude form quite small up to 4.8. Other nearby areas appear to be being tectonically disturbed by this activity, as there has been some action now to the ENE of the swarm a couple miles away. Absent GPS deformation data, all the data that exists is quake depths. USGS isn't raising any volcanic alarm bells, so it's probably safe to say still that this is not volcanic in nature, however that has not been ruled out. If it was volcanic however, you'd expect that the quake depths would get progressively shallower, which hasn't exactly occurred (they seem to be very random). Some theories abound as to whether this is related to stresses on the Cascadia fault, but I find this a bit unlikely. Yes, the fault is 'locked' and is generating an immense amount of pressure which will result (possibly soon) in a very large quake off the Oregon coast, but I see no reason to believe that the Nevada quakes are in any way related at this time.

Regardless, this is a very interesting swarm, as it has now been ongoing for over six months. I'll keep hovering over USGS for updates, but it seems they're sort of 'meh' about this swarm.

*****UPDATE 4/29/15*****
It has been several days since any meaningful quake activity has occurred in the region. It's impossible to know whether or not the swarm will continue at this point, but it seems a bit likely that it is at least dying down.

*****UPDATE 5/26/15*****

As of a few days ago, there as been little to no further quake activity in the area. At this time I think it's safe to assume that this very long lived quake swarm is over and is probably going to be quiet for a while. There is always a possibility of a few small quakes happening in the area for a while, but the sequence does at this time appear to be over. If USGS publishes a comprehensive report, I'll post it in another update or in the comments section.

*****UPDATE 7.16.2015*****
And the swarm returns. Largest in current series is magnitude 4.6 at 10km+ depth. It looks like this area will remain seismically unstable for quite a while. This swarm has now endured for nearly 1 year! There is still no definitive study done by USGS (probably due to budgetary concerns), so I can't really speculate on this at this time. Again, yes, the area has very old volcanism, and could be near to some very ancient (65,000,000 years plus) volcanic systems. However there is still no hard evidence that this is volcanic in nature. Some theories are now pointing to (and I'm not sure I agree but I'll throw it out there) pressure from the subducting Juan de Fuca plate along the Cascadia seismic zone. This 'could' be possible, however there is insufficient data to confirm this. My thought is that there is a nexus of seismic pressure causing old rocks to break. Swarms that go on for a year - if volcanic in nature - would typically have resulted in quakes getting shallower and shallower, not deeper. These have gone deeper and kind of hovered at around 10km, which suggests tectonic activity - but again, nothing has been *confirmed* without a doubt... Still keeping my eyes on it!

*****UPDATE 3/17/2016*****
It's been a long time since i posted an update to this swarm, as it has continued unabated until this week. The last quake detected above mag 1.0 occurred on 3/14/16. It could be that this series of tremors is finally coming to an end. 

Thursday, November 13, 2014

Mauna Loa Priming For Eruption [UPDATED 11/13/2014]

Mauna Loa Priming For Eruption
Hawaii’s largest volcano, Mauna Loa, is priming for eruption according to the Hawaiian Volcano Observatory (HVO). A statement from HVO says the following:

19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Seismicity continued to be slightly elevated; deformation patterns may suggest renewed inflation.

Monitoring data through the month of September 2014:

Seismicity: Seismicity at Mauna Loa remains elevated in several parts of the volcano. In late September, a swarm occurred to the west of Moku`āweoweo Crater. The swarm had a maximum magnitude of 2.4 and several events that were large enough to be located. In total, there were up to 150 separate earthquakes that were part of this swarm, most too small to be recorded on enough stations to be accurately located, however we infer that their location is similar to the formal locations of the larger events. The same area had a swarm in September and October of 2013. Several long period earthquakes were present at depths from 50 km to the shallow edifice, with most LP earthquakes between 9 and 15 km depth. Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) remain elevated, though similar to the past couple of months. Seismicity rates in the Moku`āweoweo Crater increased over previous months with approximately 50 very small events in the past month at shallow (<5 km) depths. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: On Mauna Loa, GPS data continue to show a broad pattern of displacements suggesting inflation. Preliminary modeling shows the data to be consistent with inflation of one or more magma reservoirs, with the majority of the volume accumulating in a dike-like body beneath the caldera and upper rift zones. Reinflation may have started very slowly in April or May of this year. Displacement rates have been variable, with higher rates in July and August and slowing again in September.”

While this does not mean Mauna Loa is at risk for imminent eruption, it does mean that it is more likely than before. Historically, Mauna Loa is Hawaii’s most active volcano, although it has not had an eruption since its last event in 1984. It had erupted about 33 times since its first documented eruption in 1843. Its eruption in 1984 produced some fast moving lava flows which did cause property damage, and it is likely future eruptions will be similar in style.

At this time, it would be a good idea for islanders to begin seriously preparing for a future eruption. There is no way to tell where an eruption might begin on Mauna Loa, all surrounding areas are at risk. It is interesting that Kilauea still shows no signs of stopping its eruption, as the constant outflow of lava tends to prevent rapid inflation at Mauna Loa, so this could mean Hawaii’s mantle  plume may be getting a bit more active, but that’s just speculation. If it were true, we might expect to see more activity from Loih’i, and possibly Hualai or Mauna Kea (although activity at Mauna Kea is highly unlikely).

*****UPDATE 11/13/2014*****

Mauna Loa continues to inflate. GPS readings show a broad pattern of displacement, and fumerole temperatures are rising at the summit. It is likely the volcano will erupt within the next year or so. The new report from HVO is below:


19°28'30" N 155°36'29" W, Summit Elevation 13681 ft (4170 m)
Current Volcano Alert Level: NORMAL
Current Aviation Color Code: GREEN

Seismicity continued to be slightly elevated; deformation patterns may suggest renewed inflation.

Monitoring data through the month of October 2014:

Seismicity: Earthquake rates on the Upper Southwest Rift Zone (Sulfur Cone) remain elevated, though similar to the past couple of months. Seismicity rates in the Mokuʻāweoweo Caldera remains elevated with approximately 40 very small events in the past month at shallow (<5 km) depths. All earthquakes in the past month have been small relative to earthquake sequences observed before eruptions in 1975 and 1984.

Deformation: GPS data continue to show a broad pattern of displacements suggesting inflation. Preliminary modeling shows the data to be consistent with inflation of one or more magma reservoirs, with the majority of the volume accumulating in a dike-like body beneath the caldera and upper rift zones. Reinflation may have started very slowly in April or May of this year. Displacement rates have been variable, with higher rates in July and August, slowing in September and possibly slightly picking up again near the end of October.

Gas: No significant changes in SO2, CO2 were recorded by the Mokuʻāweoweo gas monitor; however, a minor deviation in fumarole temperature was recorded over the past two months. The correlation between fumarole temperature increase, elevated seismic tremor levels, and tilt values reported in September was coincidental. This month, we've continued to record a fairly sharp anomalous 2-3 degree C temperature increase.

Background: Re-inflation of Mauna Loa's shallow magma storage reservoirs started immediately following the most recent eruption in 1984, then turned to deflation for almost a decade. In mid-2002, inflation started again, just after a brief swarm of deep long-period (LP) earthquakes. A more intense swarm of several thousand deep Long Period (LP) earthquakes occurred in late 2004, immediately preceding a dramatic increase in inflation rate. Inflation slowed again in 2006, ceased altogether in late 2009, and resumed slowly in late 2010.

Rising gradually to more than 4 km above sea level, Mauna Loa is the largest active volcano on our planet. Its long submarine flanks descend to the sea floor an additional 5 km, and the sea floor in turn is depressed by Mauna Loa's great mass another 8 km. This makes the volcano's summit about 17 km (56,000 ft) above its base! The enormous volcano covers half of the Island of Hawai`i and by itself amounts to about 85 percent of all the other Hawaiian Islands combined.

Mauna Loa is the largest active volcano on Earth and is among Earth's most active volcanoes, having erupted 33 times since its first well-documented historical eruption in 1843. Its most recent eruption was in 1984. For more information on Mauna Loa, see the USGS Fact sheet available at 


Wednesday, November 12, 2014

Italian Geologists Convicted Of Manslaughter Acquitted

In a trial that shocked the scientific world, several Italian geologists were convicted by the Italian court of 'downplaying the potential for damage of an earthquake in the L'Aquila region' in 2009. This conviction was the first precedent set to actually convict scientists for failing to do something that nobody in the world can do - predict when, where, and how strong an earthquake will be. It all started in 2009 when the L'Aquila Italy quake, a magnitude 6.3 quake, damaged historical buildings, and modern infrastructure. The damage was widespread, and during a time of economic turmoil, this exacerbated public outrage and people demanded 'someone be held responsible'.

Many in the world and media considered their convictions as precedent for forcing scientists to 'predict earthquakes'. They have now been acquitted of manslaughter charges, and released from prison after five years.

The convictions of these scientists prompted a mass-exodus of geological professionals from Italy to other countries. The fact that this ever happened damaged Italy's scientific community, seemingly irreparably. It is unclear whether the scientists acquittal will reverse the damage to the trust the scientific community had with the Italian government.

Tuesday, November 11, 2014

Quake Swarm South Of Lassen Volcanic Center

A nice quake swarm is occurring just South of Lassen Volcanic Center in California, US. The largest quake so far in the series has been a 3.9, and at this time the swarm is ongoing. So far around 35 quakes have occurred in the area over magnitude 1. It is unclear at this time whether the quakes are tectonic or volcanic in nature, however the fact that most are quite shallow could indicate this is merely a tectonic or hydrothermal event. Time will tell.

Quake swarm south of Lassen. Screenshot from Google Earth with USGS realtime quake overlay.

In all probability, as with many California quake swarms, this is related to fluid/hydrothermal movement within the crust, and probably isn't any big deal. The quakes to the East of the swarm seem to be at depths of up to 8km deep, and the ones to the West get progressively shallower. While this could indicate magma dike intrusion, that would be surprising, as some quakes are occurring on the surface, and so far there are no reports of activity in this very popular mountain hiking spot. It is likely, as most swarms in CA, that this will not result in an eruption, but it is still too early to know. 

Lassen last erupted in 1914-1917, California's only stratovolcano eruption in the last century. The eruption started with a phreatic explosion, and ended up building, and subsequently destroying, a summit lava dome which flung large boulders many miles from the summit. The famous 'Hot Rock' monument is a large boulder from this eruption. 

Lassen will likely erupt again in the future, although the current events are unlikely to make this happen. As with most West Coast volcanoes, their eruptions are infrequent, but very powerful. Should an eruption at Lassen occur in modern times, it would be more damaging than its previous eruption as the land around it has been developed.

So far, the news is slow to report, and they have less info than I do on my blog.

*****UPDATE 11/12/2014*****

The quake swarm continues. So far no quakes bigger than the 3.9. Most have been fairly near the 'middle' of the swarm area today, around depths of 4km. There has been no really detailed statement from USGS so far, other than 'swarms in this area are common' and 'this does not appear to be related to volcanic activity'. As I do not know where I could possibly view tremor plots in this area like you can with Alaskan, or Icelandic volcanoes, I can't really offer any more analysis than anyone else outside the USGS. If anything further actually develops, I'll update this post, but my guess is this is just another little swarm in the area, and not a whole lot will happen.

Tuesday, November 4, 2014

Bardarbunga Volcano Largest Eruption In Iceland In Over 200 Years

Bárðarbunga volcano in Iceland is defying expectations and is producing so much lava, it is now the second largest eruption in Iceland's history, after the 1783 eruption of Laki, which erupted for over 8 months. The current fissure eruption, which many volcanologists and bloggers like myself believe to be a precursor the main event, has now produced nearly 100 square kilometers of lava, and the gas being emitted is definitely beginning to cause problems for Icelanders, much like the Laki eruption.

Bárðarbunga volcano is a caldera and fissure system, which can be, and is, a potentially deadly combination.

Since my last blog post on the subject, not a whole lot has changed, except now some predictions such as caldera subsidence, jökullhlaups (glacier outburst floods), and massive amounts of SO2 being emitted are starting to come to fruition.

The main caldera of Bárðarbunga continues to subside at a steady rate of around 40-50cm a day, and it is showing at the caldera rim. A large 'cauldron' where the ice-covered caldera lies is clearly visible now during overflights. Other smaller 'cauldrons' are appearing near the rim as well, as heat from magma getting close to the surface warms the rock. The latest report on the caldera is saying around 2 cubic meters per second of ice is being melted (that's a lot), and they are expecting drainage at any time.

The biggest danger to people right now is twofold. The SO2 gas can and does cause lots of breathing issues, especially for people with asthma, and the elderly. People are advised to stay indoors if they encounter poor air quality, as SO2 can easily damage the alveoli in your lungs, causing permanent damage. The other threat is that of jökullhlaups, glacier flooding, which occurs when a large pocket of water is generated within a glacier, causing the temperature difference to eventually rupture out of the ice wall with near explosive force. This can happen at any time, and has caused massive damage to property and infrastructure from much smaller volcanoes.

The current situation at Bárðarbunga is getting more and more dangerous as the fissure eruption progresses. The worst case scneario right now is if the caldera continues to subside, with ice and rock eventually coming into contact with the magma conduit, which would result in not only flooding, but a very explosive eruption, much larger than that of Eyjafjallajökull, or Grimsvötn (Grimsnes). If I were to estimate the scale of the eruption, it would likely be around a VEI 3-5 event, depending on the internal mechanics.

However at this time, the eruption remains stable. Since the fissure has opened, it has consistently maintained its flow, and seismicity has decreased. This means that currently, as much magma is flowing into the dike intrusion as is being erupted as lava onto the Holhuraun lava field. If the fissure stops erupting and magma flow remains steady, it is anyone's guess as to what could occur. One possibility is that the eruption ceases altogether, which is unlikely. Another is that other fissures will open when the magma finds another route to the surface. Another is that the caldera of Bárðarbunga inflates, and an eruption occurs due to changes in caldera structure which will now have more fractures and avenues for the magma to reach the caldera.

Really, nobody knows for sure where this is going, but one thing is certain, this is a whopper of an eruption for Iceland, and is truly fascinating. FUTUREVOLC, a project which is using Iceland as a laboratory to study volcanic mechanisms is practically thrilled with the data they're able to be collecting, and Iceland itself does see an uptick in tourism. Many are braving the harsh conditions and risk of gas exposure to capture photo and video of the volcano (I'm fine right here watching the webcam), which can be risky. Earlier in the eruption, a billionaire from Europe defied orders by Iceland to stay away from the eruption site, to visit the volcano and take a 'selfie'. Believe me, this was an incredibly dangerous and stupid stunt, as any wind change could have killed the whole group.

There truly is not a whole lot else to report until something else changes with Bárðarbunga. But I did want to give a quick catch up and synopsis of what's going on there. 

Wednesday, October 29, 2014

Cerro Negro de Mayasquer Has Large Quake Swarm

On the Columbia-Argentina border, a volcano that has not had an eruption for over quite some time. There is a report of activity in 1936, however this is now assumed to have been from nearby Reventador volcano. The volcano itself does not appear to have been active during the Holocene, so it would be another in a line of eruptions of volcanoes with no historical eruptions.

Fumeroles, and hot springs are found on the volcano.

The Smithsonian GVP reports the following:

"Cerro Negro de Mayasquer | Colombia-Ecuador | 0.828°N, 77.964°W | Elevation 4445 m

On 20 October Servicio Geológico Colombiano (SGC) reported that a M 5.8 earthquake, the largest to date, occurred in the vicinity of the Cerro Negro de Mayasquer and Chiles volcanoes at a depth of less than 10 km. The event was felt to the N in Pasto (Colombia) and to the S in Quito (Ecuador). On 21 October SGC raised the Alert Level for the volcanic complex to Orange (level 3 of 4) noting that a seismic swarm characterized by 4,300 earthquakes was detected in an 18-hour period. Hypocenters were located 1-4 km SW of Chiles volcano at depths of 3-5 km and local magnitudes between M 0.2 and 4.5. Inhabitants felt 11 of the events. On 22 October a report noted that the total number of earthquakes recorded on 21 October reached 7,717, which was the largest number of earthquakes recorded on one day since the installation of a local seismic network in November 2013. Several swarms have occurred in the area since February 2013."

Since this report, around 12,000 people have been evacuated as the number and magnitude of quakes have sharply increased since October 24th. It is looking likely this volcano will erupt.

The South American West Coast has had several eruptions from long-dormant volcanoes recently. Chile's Chaiten volcano erupted after more than 8,000 years of dormancy in a large rhyolitic explosion. There has been seismic activity recorded at Machin volcano in Columbia, which has been dormant for 8,000 years. Other long-dormant or presumed extinct volcanoes have also erupted in Africa and the Red Sea, such as Nabro volcano in Eritrea (which was presumed to be a dead Pliestocene volcano), and Jebel Zubair/Jebel Al-Tair volcanoes.

This only means that no volcano should ever truly be deemed 'dead', especially if it is in line with, and surrounded by other active volcanoes.

Friday, September 12, 2014

Bárðarbunga Volcano Disrupting Other Volcanoes?

Tungnafellsjökull volcano rumbles, Askja volcano quakes, and Herðubreið shakes. What is going on in Iceland? Bárðarbunga's new activity and magma intrusion does indeed seem to be 'squeezing' neighboring volcanoes into a state of higher seismicity. To the West of the Bárðarbunga caldera lies a Pliestocene-Holocene volcano called Tungnafellsjökull, which contains a large caldera, and shield volcano. It has no record of activity during human occupation of Iceland, and it's uncertain whether it has erupted in the last 8,000 years.

Askja volcano, to the North, and neighboring Herðubreið volcano, a Tuya, are also experiencing heightened quake activity. Askja is responsible for one of Iceland's largest eruptions in historical time, which created a caldera (which is now filled by a lake), and fissure eruptions on its flanks. Herðubreið has not erupted in historical time, yet now there appears to be persistent seismic disturbances happening beneath its summit.

So what could be happening? Well, a few things really, but none of them appear to be precursors to imminent eruption... yet...

Tungnafellsjökull is characterized by the Smithsonian GVP:

"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."

Earthqauke activity at Tungnafellsjökull has picked up since the dike intrusions, eruptions, and unrest at Bárðarbunga, leading some to believe that it could be 'reactivated' as a result of the crustal pressures. Indeed, magma can remain hot and ready in a volcanic system for a long time, slowly cooling into what's known as 'crystal mush'. In this state, the magma is more viscous and thick, and not typically ready to erupt unless it gets new magma injection... but what happens when a magma chamber gets 'squeezed', as I suspect is happening. Does it build pressure, causing rock fracture, and possible unrest? I see this scenario as most likely... but so far there has not been any opinions generated by Iceland volcanologists (they tend to shy away from 'opinion' and rely on data).

When a large rush of magma from what is probably the main magma plume in Iceland starts moving mountains, you can bet there will be some activity in other parts. Whether or not this generates eruptions in other volcanoes around Bárðarbunga is anyone's guess right now. Typically volcanoes require fresh magma and immense pressure to erupt, but I've never seen an eruption quite like the one in Bárðarbunga, with such rapid ascent of magma dikes and sustained lava flow. Only Kilauea tends to erupt this way, and like Iceland, its volcanic system is attributed to a magma plume or hot spot. The difference is Iceland's hot spot sits on the mid oceanic spreading ridge between the North American and European plates, which spread apart, making eruptions in Iceland potentially more drastic.

In any case, the situation in Iceland is highly dynamic at this point. Good place to keep your eye on for now.

Thursday, September 11, 2014

Bárðarbunga Eruption Continues With Potential For Caldera Collapse

This is a continuation of the main blog post about Bárðarbunga.

Bárðarbunga continues it's fissure eruption north of Vatnajökull in the 
Holuhraun lava field, and signs are indicating that the main caldera of Bárðarbunga is starting to collapse. If I haven't stated this before, that's going to be very bad news for Icelanders if it occurs, however, it's going to be a slow process that can take months. What could happen? Under the main caldera is a magma chamber. That chamber was cut by the magma dike that is feeding the fissure eruption to the north. This allowed magma which was previously stored in the large chamber to escape northward, potentially leaving a void in the chamber. 

Without all that magma to support the chamber ceiling with pressure, gravity takes its toll, and the volcanoes caldera walls begin to get sucked into the void. Once it fully collapses, tons of solid rock, ice, and melt water will come into direct contact with the magma at the bottom of the chamber, resulting in a very large explosion. This explosion will have high concentrations of ash, and gas, and could spur a week-long eruption similar in style to the Grimsvötn eruption, but on a larger scale. This absolutely would disrupt air traffic, and will result in massive flooding to the West of the caldera. 

Currently, there are no signs the eruption is stopping. IMO reports that they think the amount of lava being erupted by the fissure north of the Bárðarbunga caldera is probably equal or less than the amount of magma entering the dike and chamber, which means the system is STILL very much primed for more action, which at this point will probably occur. No less than seven eruptions (6 of them subglacial, and quite short lived) have been confirmed so far, so the entire region has a potential to spawn a new fissure at any time, and the slow subsidence of the Bárðarbunga caldera is very worrying.

Icelandic scientists will probably not sound this dire in their press releases, because if they sound the alarms and nothing happens, public trust erodes. I am in the 'better safe than sorry' crowd, myself, and would advise people to make plans to evacuate flood plains well in advance of this impending eruption. There are simply no signs right now that this eruption will be coming to an end any time soon, and the longer it goes, the greater the danger will be to those who have not prepared.

Monday, September 8, 2014

Oregon's Mount Hood Rumbles.

Oregon's Mount Hood, one of the famed Cascades volcanoes, has produced a few shallow earthquakes below the summit. What this means is uncertain, but it is probably typical of the volcano. Mt Hood last erupted in 1866 although there are some unconfirmed reports of eruptions in the very early 1900's. A magnitude 2.6 quake occurred below the summit at 3.7km depth, and a much shallower 2.1 one at 0.9km depth. There are currently no reports on these quakes at CVO or USGS.

At this time it is unlikely this means an eruption is occurring, but it could mean anything.

Google Earth with USGS overlay showing 2.6 quake near summit of Mt Hood, Oregon, USA

Images from CVO website showing approximate magnitudes and depths.

Earthquake swarms are common at Mt Hood, they are not out of the ordinary. If these were volcanic quakes, there would probably be a lot more of them. Hood is a very well monitored volcano, as it has the potential to be very dangerous if it erupts. Like most Cascades range volcanoes, it is covered with glaciers, which can be a problem if lava comes into contact with it, or melts the ice. Lahars, landslides, and ash are all potential hazards if Hood ever erupts.

the last large quake at Hood was a magnitude 4.5 in 2002, which occurred beneath the summit at a depth of around 4.5km. This of course did not result in an eruption.

Right now it's way too soon to tell if this means anything or not, but as with all USA mainland volcanoes, it's best to remain vigilant and keep up to date with their goings-on.

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. 


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 9/5]


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 

*****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

*****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.


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 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 

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 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:

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.

*****UPDATE 9/3/2014 @ 2:30pm PST*****

This might end up being the last update for a couple days on the situation as it is no longer as dynamic as it was, but maybe not if something changes. The fissure continues to erupt at approximately the same or higher rate. Lava continues to flow onto the surface, and SO2 emissions are high. This is likely to continue for some time, as IMO has determined that now more magma is flowing into the dike than out of the fissure. It is still very possible that an eruption at the main caldera will take place, but unless something big changes, I'll move on to reporting other eruptions, as the situations in Ecuador, Indonesia, and Alaska need some love too. 

*****UPDATE 9/4/2014 @ 2:15pm PST*****

Google Earth has made it possible to do a lot of cool things. NASA released a satellite view of Bardarbunga, and I laid it over a Google Earth landscape to show the changes. Check out the pic below (which is already outdated, the lava creeps fast). Enjoy.

Image of the lava flow from Bardarbunga, to scale, over the lava field north of Vatnajökull.

*****UPDATE 9/5/2014 @ 12:50pm PST*****

A second (or perhaps third) fissure has opened up south of the current fissure and has begun erupting. This is still apparently outside of the glacier zone, so no explosive eruptions or floods are yet expected. The 'cauldron' in the glacier has apparently gotten deeper, signifying that some heat is going on down there. Whether it's an eruption is a mystery at this time. Statement from IMO and their analysis can be found here.