Sinabung and Etna updates for 8/30/2010

Classes starting today, so I have to be brief:

Unique twin ash plumes from Sinabung in Indonesia, erupting on August 29, 2010.

The Indonesian volcano continues to experience explosions, which one last night (well, last night here in Ohio) that prompted an ash advisory for aircraft up to 6,100 m / 20,000 feet, although most reports I've seen pegged the ash column at closer to 2,000 m / ~6,500 feet. Eruptions readers have found a bevy of links for footage and information about the eruption, including a remarkable image gallery from the BBC that shows the volcano exhibiting two ash plumes - one that is vertical, one that is shooting off to one side (see above). This definitely makes it seem that the vent is partially blocked and these explosions are helping "clear the throat" of the volcano (NOTE: this does NOT mean I think something big is going to happen, rather just that it seems to be the reasonable explanation for the bifurcation of the plume). My hunch is that even now, very little "new" juvenile magma has been erupted from Sinabung, but that is pure speculation until there are any analyses of the ash shard morphology or composition.

There is also some video from Portuguese television Some of the most recent images from the volcano show a strong, single plume with some rock avalanches (possible block and ash flows) on the flanks. Evacuations have increased to over 21,000 people living near the volcano and some flights have been diverted due to the taller ash plume. The biggest threat right now is the ash fall from the explosions and as such, the government is providing face masks and moving people to sturdier shelter. The current death toll appears to be 8 (video), mostly from respiratory-related problems. What comes next might be a guess for everyone at this point as the Surono, head of the Indonesian Center for Volcanology and Geological Disaster Mitigation admitted again "We don't know what set it off, how long it will continue or whether to expect pyroclastic flows or more powerful eruptions."

Not to be forgotten, Etna continues to show signs that it is entering a new cycle of eruptive activity as well (albeit much less of a surprise than Sinabung). Dr. Boris Behncke points us to some new updates from the INGV (italian - top and english - bottom) that describe the explosions and collapses that have been producing the ash fall on Sicily. Be sure to check out Dr. Behncke's Photostream for the latest and greatest images of the current activity at Etna - currently he has some close ups of the explosions occurring in the Bocca Nuova crater (not to be missed). You can always watch Etna's show on the multitude of webcams as well.

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Just a little correction - the updates at the INGV web site are now both in Italian AND in English (I am personally taking care of that!), though the titles remain in Italian so far.

For another list of Etna web cams, compiled by my friends of the Hotel Corsaro, look here:
I also hope we will soon have the images of the new Montagnola (upper south flank of Etna) web cams, both visible light and thermal, on-line on the public pages of the INGV.

As for Sinabung, unfortunately there seems to be very little instrumental monitoring at this volcano, and thus it is extremely difficult to say what will happen there. Go figure, it's often difficult even to forecast the behavior of a volcano that is extremely well monitored! All depends on the signs that a volcano gives, and how they fit with previous records. At Sinabung there is little of the two, poor instrumental monitoring, and no data for comparison. I hope the volcanologists there will soon have the possibility to install more monitoring equipment - at Pinatubo in 1991, such action helped to save tens of thousands of lives.

Thanks for correction, Boris. I thought you said that but then the page said "There are no translations available" so I was a little confused. Maybe I should have just, you know, read the english (funny how the brain works on no coffee).

@Erik, ah yes the coffee factor ... I am lost without having had my morning coffee, especially under the climatic conditions in Sicily; let's hope Etna will always allow me to have a good Sicilian coffee before getting to work :

Is Sinabung monitoring data publicly available?

@Boris Behncke, Catania, Italy, I am sorry to ask you here. But did you get my email, or did it get lost in the black hole of the internet known as /dev/null.

As for the Sinabung volcano, the few indicators that I get are no good. This eruption appears to be on the phase of dropping and re-starting again with more power. Given the few and little data that I get. But overall this does not look good at the moment. It is also a big factor that the volcano is awakening from a long period of dormancy, and that might not be a good thing.

I am assuming (given the data) that new magma is pushing out and re-warming older magma that was left in the magma tubes inside the volcano since the current eruption started. When the new material might reached the surface is a good guess, but I think that is going to happen sooner rather then later.

Even if events this far bear an uncanny resemblance to both Tambora and Pinatubo, that's not to say a major eruption is inevitable.

Or? ;)

By Henrik, Swe (not verified) on 30 Aug 2010 #permalink

"Is Sinabung monitoring data publicly available??" (Mr Moho #5)

According to… PVMBG head (Dr?) Surono is quoted as saying "We never monitored the development of Mt. Sinabung because it was considered extinct".

The same article explains the division of Indonesian volcanoes into A, B and C as follows: "The center classifies type A volcanoes as having erupted at least once since 1600, type B as never having erupted since 1600, but showing signs of volcanic activity, and type C as never having erupted in recorded history."

This makes sense in a country with hundreds of volcanoes to monitor and limited funding to do so. Before we shake our heads, how well is - say - Colli Albani or the EEVF monitored...?

By Henrik, Swe (not verified) on 30 Aug 2010 #permalink

I know that correlation does not imply causation, and history does not always repeat itself. However, Sinabung has a neighbor (Toba) with a very bad reputation, just over 30km to the southwest. I would think that the proximity of the two would warrant a little extra caution in the case of Sinabung. The evidence of what can happen during a worst-case scenario eruption is a 35-100km caldera that is located right next-door.
I know that another Toba, Tambora, Krakatau, or even a Pinatubo is unlikely; however, I'd keep my distance!

Quake felt on Mount Sinabung. Tuesday, Aug 31, 2010

A five-minute earthquake rattled villages near Mount Sinabung, North Sumatra, on Monday as the volcano continued to spew ash clouds.

Irfin Dian, a Kabanjahe resident, said the temblor was felt for five minutes, before Mount Sinabung spewed thick black clouds.

@Doug C., The problem is that the government of many countries don't think like that.

This same issue is also in place in Iceland. Where a string of volcanoes is not monitored at all. Even if some of those volcanoes did erupt about 1000 to 1500 years ago. Those volcanoes are on Snæfellsnes peninsula. So this problem is not unique in Indonesia, far from it.

The unmonitored volcanoes of Iceland.

Doug C. (and others) - Tread carefully when trying to connect volcanic systems like that. Remember, these are volcanic arcs where volcanoes are close to each other, but horizontal distance doesn't mean much in most cases. I mean, we don't worry about Mt. Adams erupting if Saint Helens is active even though they are quite close together. There are examples where the systems appear to be interconnected (or at least stacked) such as Katmai, Alaska (1912), but linear distance is never a good way to connect volcanoes without other evidence.


One reason for the discrepancy between the Volcanic Ash Advisory Center and Indonesian reports of ash plume height may be the elevation of the summit. VAACs give heights above sea level, and the Indonesia authorities appear to be giving heights above the 2,460-meter summit. 2,000 + 2,460 is pretty close to the 6,000 meters reported by the VAAC.

One question: You mention that you suspect there is little new magma in the system, but reports I've read state that there are lava flows on the surface. Is this consistent?


#12 There's a link for earthquakes from Indonesia Met Service
They had a 5.2 EQ, in Papua and another 4+ in Miamar, but too far from the area of our interest.
@Passerby I believe both an eruption and a strong earthquake are likely at the Great Sumatran Fault. The next strike slip megathrust is expected at the plate boundary, but further to the South (Padang region).
@Lurking, quakes in Indonesia are so large that you can't tell precisely if they are tectonic or volcanic. Hope the link above gives us some more info on the smaller ones.

By Renato Rio (not verified) on 30 Aug 2010 #permalink

Another at a local newspaper saying that there were six volcanic quakes yesterday in Sinabug:
"Kabanjahe - In accordance with data obtained by the Online Alert Sinabung from post disaster response in Karo Regency Road Veterans Hall Kabanjahe, volcanic earthquakes have occurred six times in Sinabung between the hours of 00:00 pm - 7:15 pm, today". Nice picture form the volcano.…

By Renato Rio (not verified) on 30 Aug 2010 #permalink

R Simmons - I've been trying to find a reliable source about the lava sighting, but there is nothing yet. My hunch is that it could be rock being lit from glowing in the crater mistaken as lava, but that is just speculation. However, if lava is confirmed, then that is definitely new material.

The historical eruption record of Sinabung should give a clue about the developement of the ongoing eruption. Volcanoes tend to repeat themselves. For example in the case of Mount Pinatubo the vulcanologist saw the marks of ancient violent explosive events in the terrain at the volcano and could expect the same type of eruption again. And the explosive eruption did happen. The same thing with Sinabung, what does the historical eruption record at the volcano tell the vulcanologists this time?

>what does the historical eruption record at the volcano tell the vulcanologists this time?

Damn little. The updated wikipedia page reports,

>scientists were unfamiliar with the characteristics of the volcano, due to it having been dormant for so long.

From the Pinatubo wikipage,

>Although there seems to be no local knowledge of the previous large eruptions in the Pinatubo area, several Aeta residents reported in 1991 that their elders recalled small explosions in the past. Pinatubo was a known geothermal area before the 1991 eruption, and small steam explosions are quite common in such areas. It was only after volcanic activity began in 1991 that geologists studied the eruptive history of the region in any detail. Eruptions at the site can be divided into two major eras.

It was only after the eruption that geologists determined 'modern Pinatubo' (differentiating it from ancestral volcano active 1+ MYA) previous eruption history:

'Earlier large eruptions occurred 17,000, 9000, 6000 â 5000, and 3900 â 2300± years ago.'

That is the extent of the similarity between Pinatubo and Sinabung: they both were relatively unstudied until they erupted, and they have small eruptions and were geothermally active.

Prehistoric eruptive history of Sinabung is unknown at present.

Villard: that's one of the things about Sinabung that is so worrying; has there ever been a detailed geological survey of it? There is probably something gathering dust in some Dutch academic archive and all-but forgotten, (as the 1930s identification of Lamington as a volcano was forgotten) which might give some clues. In Pinatubo's case PHIVOLCS had to start more or less from scratch, and fortunately the volcano gave them time to do it

Lake Toba, a supervolcano is nearby? Correct?

By Greg Lennes (not verified) on 30 Aug 2010 #permalink

Just to say Thanks to Boris....your blog is really nice, so I'm totally addict. I've seen your pictures from Etna...and I can recognize one with the lava's flow on the building...I've here when I was 11 years old...
I've no more reason not come on Sicily at the last see Mr Etna and miss Sea....
Thanks a lot for all your staff on the Net...I have a look on Eric and Boris Blog every night...

More Sinabung video here:

Erik: I wonder if the 'lava' reports are actually describing avalanches of incandescent blocks down the flank -if the vent is slightly below the actual summit this would make sense.

#25 Both "Der Spegel" and "RTP - Portuguese TV" mention lava, but it could well be the woodfires downslope. The slopes are steep enough for rocks to be rolled down to the feet.
As for the Toba connection, if I'm correct, what we were speculating about was not that there is a common magma source for both volcanoes, but that all volcanoes in that area (Toba included) lie on the same faulting system across the Great Sumatran fault that could respond for a crustal thinning, like it happened in Krakatoa, and which have undergone huge stresses after all megathrust earthquakes at the adjacent plate boundary. Besides, the diffuse boundary between Indian and Australian plate is being subducted right underneath the region, making this a triple junction spot.

By Renato Rio (not verified) on 30 Aug 2010 #permalink

#2,3 - Wasn't it someone somewhere before that said that "a volcanologist is a device to convert coffee into maybes and a newspaperman is a device to convert maybes into 'AAARGH! ITS GUNNA BLOOOW!!!!!'"?

By Reynir, NK, .is (not verified) on 30 Aug 2010 #permalink

@Renato Rio

Yeah, that's one of the sites that is of little use. More script than you can shake a stick at and nothing small to plot. It's faster just grabbing the data from USGS which flows in from the cooperative networks.

I think not even the richest countries spend enough money for observing and measuring each of their volcanoes, how can one think that a not too rich country like Indonesia will do it? How can we await them to do it? If someone would like to get more info, send them money, send measuring devices, educate the staff to work with the devices and after it the info will come...
Hopefully this one will not be a major eruption and after it would stop, some scientist would go there and go back in time with the earlier times' rocks and clear the history of this volcano with scientific accuracy.

Heads Up Iceland.

The remains of Danielle could be in your area doing sort of a reverse recurve in about 96 hours.

Water + Fresh volcanic ash = Mud.

I'm sure 'yall are already aware of the hazards. We just had 6 to 8 inches of non-storm tropical rain here. God forbid you get any rain like that.

It's as obvious that vulcanology is an underfunded science as it is that sports in general and football (soccer, that most accursed of plagues to afflict humanity) in particular attract public, and thus corporate, interest far in excess of any merit, imagined or real. It's a safe bet that a microscopic fraction of what a nation such as Guatemala spends on tv-coverage of their national soccer championship would pay for adequate monitoring of Santa Maria and Santiaguito, same as it's a safe bet that Silvio Berlusconi spends more in a single month in his personal capacity as owner of AC Milan than he has ever done on the INGV in his capacity as head of the Italian government.

Then again, it may well be a case of "panem et circences" - without the pseudo-reality of sports to keep the masses otherwise occupied, who would care if a few ten thousands could perish because Santa Maria "might" erupt catastrophically within the next ten to two hundred years or that Rome "might" be flattened by an eruption at Colli Albani within the next ten thousand years...

By Henrik, Swe (not verified) on 30 Aug 2010 #permalink

Quick question. Can there be a "negative" magma intrusion? What i mean is can there be a conduit where magma is pushing diagonally downwards and that this would show on seismometers?
If there was a blockage could this happen?

By Daniel_swe (not verified) on 30 Aug 2010 #permalink

"how can one think that a not too rich country like Indonesia will do it?"

Throwing the B/S flag on that one.

GDP Comparison:
Iceland - $12.15 billion (2009 est.)
country comparison to the world: 142

Columbia - $401.5 billion (2009 est.)
country comparison to the world: 29

Indonesia - $962.5 billion (2009 est.)
country comparison to the world: 16

Indonesian video site here with some local news clips:

i read (here: [url][/url]) that the volcano has four craters:
"Sinabung volcano contains four overlapping summit craters, with solfatara activity present during the 20th century. The cone shows evidence of many lava flows.

Crater 1. Diameter 300 m.
Crater 2. Diameter 150 m. Contains crater lake.
Crater 3 (Batu Sigala). 160 m x 130 m. Contains crater lake.
Crater 4. Diameter 60 m."

there was a lot of white 'smoke' (steam?) in one of the videos. Could that have been one of the crater lakes going up, or would that be more violent?

#33 @Lurking

If you look at the GDP only, it may appear to be a valid argument. But if you take into account the populations sizes:

Iceland: ~313,000
Colombia: ~45,586,000
Indonesia: ~229,965,000
(all numbers taken from Wikipedia)

Then the GDP per capita comes to:

Iceland: $ ~38,000 per person
Colombia: $ ~9,000 per person
Indonesia: $ ~4,400 per person

Given those numbers it is clearer why Indonesia may have a harder time at monitoring its many volcanos.

By Holger, N California (not verified) on 30 Aug 2010 #permalink

I'm not a geologist but this looks ominous, with parallels to Pinatubo:

- several centuries of dormancy
- unknown history
- blocked vent slowly being cleared?
- rumblings / pressure release of remelted old magma? (And what could be re-melting it?)

Add in the 2004 megathrust quake and what it may have done to the deeper magma chambers over the past 5-6 years, slowly working its way upward.

Can someone give a tip to the authorities there that there may need to be a sufficiently large evacuation area?

The Pacific Network station 21 - PSI located at 2.69N - 98.92E is located at Toba and shows data going back to 1993.

According to the data card it's a Streckeisen STS-1H/VBB Seismometer.

The IRIS queries via BUD work for the eruptive data, and show activity that seems to be coincident with the eruption.

Not being a seismologist, I can't really read it. But those of you who have that skill might want to poke around at it.

Here's the link:

As for the GDP, you have to remember that this is the same government that is still sitting on compensation from the Sidoarjo Mud Volcano case. A prominent politician Aburizal Bakrie, Minister of Welfare, has spent a good part of his time trying to distance himself from the event, see, his family business is part owner of PT Lapindo Brantas, the drilling company that caused the event. In 2008, one of the companies owners hired a London public relations agency to try and wash the carp off of the event. (similar to BP's current tactics)

So no, I'm still not buying the BS.

Flowing since 2006:

Now... is it me, or is that trace climbing?

Got to be my eyes.

According to… PVMBG head (Dr?) Surono is quoted as saying "We never monitored the development of Mt. Sinabung because it was considered extinct".

"Considered extinct" - What nonsense. Extinct in the fact it hasn't erupted for 400 years? Extinct in the fact that it has been emitting sulpuric fumes for hundreds of years? There are dormant domes all around Sinabung, an active caldera (Singkut) only 10 ks away and the Toba Caldera less than 30 ks away.

This may be the same Dr Surono that assured the local people last Friday that Sinabung would never erupt.

Sinabung has 4 craters - at varying levels. It seems obvious that at least two of these craters are currently emitting ash and steam.

My family has a hill station holiday house built on a dormant dome only 10ks - line of sight from Sinabung. It's overshadowed by Sibayak.

By Les Francis (not verified) on 30 Aug 2010 #permalink

The Indonesian Directorate of Volcanology and Geological Hazard Mitigation (VSI), Bandung is back in action. They may have gone offline yesterday due to overload (excluding external traffic) or been down for maintenance.

Indonesian government's volcano, earthquake and tsunami monitoring program is not a trivial operation. They monitor 76-80 active volcanoes and several of the worlds largest and most violent fault systems through a large network of observatories and employ a considerable staff of well-trained geologists. VSI employs sophisticated seismic and deformation monitoring equipment, needed to provide hazard risk control and response for the most geologically active area in the world.

Nearly all of Indonesia's active volcanoes have erupted within the last 100 years; the nation has been rocked by several of the largest earthquakes, and a very high number of moderate quakes in half that time span.

Indonesia doesn't have glaciers to contend with, but global climate change can and does affect earthquake and volcanic activity via subduction and double Benioff zones. In Sumatra's case, temperature changes could be linked to highly fractured, relatively younger and warmer crust being sucked under the Eurasian plate off the coast of North Sumatra due to sea level fluctuation.

VSI gets by a little help from their friends...hazard monitoring program coverage from Tokoyo VAAC, earthquake and eruption satellite monitoring from ASEAN, USGS and longterm studies conducted by international collaborates at various academic centers around the planet.

@Les Francis, If you can afford it, you really should get a amateur geophone with GPS clock to record earthquakes and watch for volcano tremors. You never know when that type of hardware might save you some trouble if you live in a really earthquake and volcano active area.

Just drop me a email if you want to setup earthquake monitoring hardware. The cost is about $400 to $600, depending on hardware configuration. I don't sell or make this, but I can point to in the direction of a man how does.

I love the forked eruption.

By Dasnowskier (not verified) on 30 Aug 2010 #permalink

a volcanic ash plume above 10km high into the stratosphere would be a big deal to global agriculture given the equatorial location of this site could allow aerosols to enter both hemispheres jet streams inducing a short-term global cooling event this winter into 2011.

Only one of the two tremor graphs shows the rise, the other is flat. ...

Posted by: Passerby | August 30, 2010 10:12 PM

Ummm that would be an understatement. Whatever the data represents it is apt to be strongly processed.

The last minor explosion (?) was at 07:20 on the 30th and since then there is nothing save for the ramp up in that tremor chart.

It's a bit suspenseful no?…â©=it

Well, Raving, you're an engineer, correct? You must have seen baseline drift in signal output from sensor equipment. Could be instrument error, could be cultural noise or weather effects, as Jon mentions.

Not terribly worried over it, to be honest.

Can't find recent updates on Sinabung. Kind wondering if the area has gas emissions, maybe CO. Got carbonate deposits here; groundwater is carbonate-chloride enriched. Reports of sulfur make sense (major sulfur deposits from fumarolic activity and SO2 and H2S have been measured in the nearby hot springs).

Real quick like for the evacuees (moved about 4-6 Km away from the volcano) to be experiencing gastrointestinal, respiratory and nervous system systems. I don't think it's from contaminated water, as the news reports suggest.

If I'm right about the geothermal activity kicking up, then it's likely to be causing increased degrassing in the numerous hydrothermal systems in the area, maybe including where the evacuation centers are set up.

Also, reports of several dying from ash inhalation raise eyebrows. Doesn't happen very often.

CO would bring on respiratory stress and might kick up risk of heart attacks in folks with cardiovascular disease.

@Sam Mende

I can't find the references, but the average troposphere depth is about 17 km. 20 km in the tropics and about 7 km near the poles. Above that is the stratosphere.

In a paper... the one I can't @#$$@# find, there was a discussion about the effects of relative moisture content of tropical air verses higher latitudes on the amount of SO2 that actually made it that high. In a nutshell, the higher humidity tends to leech the SO2 faster from the eruptive column.

What this roughly means is that a lower percentage of the SO2 actually makes it to the stratosphere as SO2... already converted H2SO4? Maybe. But tropical systems have to have more punch to reach it.

If the system comes up with a Pinatubo level eruption, then I'll start looking for more of those purple sunsets. I'm also pretty sure that several thousand people in Indonesia will be freaking out.

Eh... close.

The variability of SO2 loss rates is found to be correlated with the variability of wind speeds, suggesting that it is much more difficult to establish a âtypicalâ SO2 loss rate for volcanoes that are exposed to changeable winds. Within an average distance of 70 km away from the active Indonesian volcanoes, 53% of SO2 loss is due to conversion to SO2â 4 , 42% due to dry deposition, and 5% due to lateral transport away from the dominant direction of plume travel.

Atmospheric transport and deposition of Indonesian volcanic emissions
M. A. Pfeffer1, B. Langmann1, and H.-F. Graf

Atmos. Chem. Phys., 6, 2525â2537, 2006

Possibility of a massive earthquake at Sinabung region:
According to the Jakarta Post:
"Asked about the tremor that resembled a quake felt by residents during the eruption, Jonathan said it was possible the clogged crater was pushed by steam, causing the tremor.
He added he was concerned the eruption might serve as a sign of a looming massive quake in Karo regency."

By Renato Rio (not verified) on 30 Aug 2010 #permalink

I can't read these things to save my arse.

This is the most recent pull from the seed for the PS station over at Toba. It's a few miles away from Sinabung.

Channel BHZ is blue, on top, Channel BHN is yellow, in the middle, and Channel BHE is purple, on the bottom. Time is in UTC


@Lurking: Channel BHE shows a very slight rise (to my lay eyes). Though I think this volcano has yet more stories to tell. Matsabanga News Online mentions people fleeing from fear of lava "which was visible in daylight" More than 5000 refugees show bleeding and respiratory conditions. Hmmm... not good.
But it seems that authorities of Indonesia are taking their precautions and rising their concern for other volcanoes at the Aceh Province.
"It was announced by responding to questions the level of vulnerability to the three volcanoes in Indonesia, namely Glee Peuet Sagoe (Pidie), Seulawah Agam (Aceh Besar) and Bumi Telong (highlands)"

By Renato Rio (not verified) on 30 Aug 2010 #permalink

please check the official site Pusat Vulkanologi dan Mitigasi Bencana Geologi[PVMBG] (Centre of Volcanology and Geological Hazard Mitigation)

maybe u can find something useful there

Gavin 37: While it's not entirely reassuring, it seems that Pinatubo and Sinabung have had very different eruption styles. Pinatubo (as Passerby posted earlier) has produced major explosive eruptions accompanied/followed by dome growth, at very long intervals. Whereas Sinabung's flanks have notable "prominent leveed lava flows" (GVP Profile) including the south flank, below the youngest summit crater, indicating that fairly recent -geologically- eruptions have been more moderate (if that's the right word)

One Finnish newspaper states, that people living near Sinabung have started to return to their homes, as the mountain seems to have calmed down a bit and is currently producing only white steam.

In the morning of August, 31 st, Government volcanologist Agus Budiantoour said "our instruments have recorded continuous tremors in the volcano, which means that there is magma trying to push upward.â
He said the situation remained too precarious for people who live closest to the volcano to go home.
âWe predict that thereâs still a possibility that it will erupt again,â he said, adding there was âno planâ to downgrade the threat level.
Airlines have been warned to avoid Mount Sinabung in northern Sumatra but the area is remote and the ash cloud has caused minimal flight problems." |url|…|url|

By Renato Rio (not verified) on 30 Aug 2010 #permalink

@All: if anyone needs a hand in translating indonesian article from a local news, just let me know, sometimes even google translate not with a right grammar.. :)

little update from several local news today, there's no high activity today at mount sinabung, some analyst said that because the pressure at the magma chamber under the volcano is decrease..

but the Presidential Special staff of the Disaster and Social Affairs said that it's not end yet, from the size of the volcano, a big eruption could happen and the effect will be catastrophic to third biggest city in indonesia, Medan and surrounding country like Malaysia and Singapore.

in the other hand, Head of Geological Agency Ministry of Energy and Mineral Resources,R Sukyar said this morning that a new crater creates after the second eruption and creation of a new crater on the top Sinabung can reduce the pressure of magma under the volcano.

What u guys think about this?

@Willem (#35). Take a look at Friday's pictures and note the large, yellowish area high up on the flank. It's evidence of of solfataric activity from a flank vent (correct Drs K, B, EKoh, Gijs?). Together with the weird, initially horizontal vent visible in the OP, I'd personally stay well away from that side of the volcano.

@Raving (#39). A great deal of our human pursuits fall into the "non-neccessity, frivolous waste" category such as the fact that in the '60s, US women spent twice as much on cosmetics as Uncle Sam did on NASA annually. So yes, even if I admit to being a cricket afficionado, I would in the name of intellectual honesty have to include Mohammad Amir and others currently under investigation. What really is an outrage though is that AC Milan just spent over 100 million euros to obtain the services of one of my country men and no one is ever going to convince me that this money couldn't have served humanity far better. Why not a 10% "Football Tax" to fund neccessary public safety projects? ;)

@Les Francis (#42)! Hang on! The operant phrase is "quoted as saying". Dr Surono may very well have said that Sinabung was not monitored because it was a Category B volcano and the journalist, either with an axe to grind or wanting to increase his journalistic standing, exchanged "Category B" for "extinct". With some 129(?) active, or Category A, volcanoes to worry about and who knows how many thousand Category B & C volcanoes or volcanic complexes in the country, do you really blame him personally for not watching Sinabung? Since your family "has a hill station holiday house built on a dormant dome only 10ks - line of sight from Sinabung", your apprehension is eminently understandable. Jon Friman's advice (#45) is good advice.

By Henrik, Swe (not verified) on 30 Aug 2010 #permalink

Hi Erik, it seems, that the plume was erupted from two different vents. Sinabung have got 4 craters along a N-S extended fissure. What do you think, is it possible, that a lavadome will grow up?

Best Regards, Marc.

P.S. A great blog you have establish!

@Henrik: I saw, and also seemed to see an orange spot in the yellow area that indicates molten sulphur coming out of those vents (picture:…). Have seen that before and often in Indonesia local villagers will substitute their income by 'mining' this sulphur in huge blocks, so there's a good chance there are some well trodden paths into that area.

Sinabung ... Looking at the difference in 24 hours:

One vent column becomes two.

Vented material increases in volume and turns from white to black.

Hmmm. And nobody knows what to expect next. :(

By William M Boston (not verified) on 30 Aug 2010 #permalink

William, when I zoom in I see two vents (and two small avalanches) in the top picture. Interesting comparison seeing them side-by-side like that, thx!

By Henrik, Swe (not verified) on 31 Aug 2010 #permalink

There has been indeed an increase in the amplitude of the volcanic tremor at Etna over the past 24 hours, which is evident on most seismic stations, especially those near the summit. All of you who watch the two Etna tremor graphs that are accessible to the public, be aware you're seeing a very partial image of what is going on.

Somebody remarked in an earlier thread on the fact that not all data are made public - I had explained this with Civil Defense issues, which as a matter of fact is the truth: since our institute is largely funded by the Italian Civil Defense department, they do have some sort of an intellectual property of these data, although in the end it's us - the scientists of the INGV - who are competent to elaborate and interpret the data.

The way how such instrumental data and their interpretation - often a very sensitive affair, since we're talking about the lives and property of millions of people being at stake - should be made public is very much discussed, not only here in Italy. It is a general aim to avoid confusion as much as possible, which is likely to increase with a higher number of interpretations and speculations in circulation, also on blogs as this one, which is under constant observation by the news media waiting for the most sensational and horrible breaking news.

Unfortunately there have been events in the past when disagreement between different groups of scientists was directly brought to the news media by the very actors - the volcanologists - with devastating consequences for the credibility of our discipline. The most outstanding example is the Soufrière (Guadeloupe - West Indies) 1976-1977 crisis. In that case two groups of volcanologists had contrasting views on the threat presented by a volcano that had in the past had both cataclysmic, pyroclastic-flow-producing eruptions and small, harmless phreatic explosions. Those views were discussed before the news media from all over the world, causing confusion and disbelief among the affected population (about 73,000 people were evacuated from their homes and business for about 4 months), and eventually the volcano did not erupt catastrophically.

It is well possible that the immensely - yet avoidable - disastrous consequences of the relatively small eruption of Nevado del Ruiz (Colombia) on 13 November 1985 were at least in part due to the Soufrière 1976-1977 affair. In order to avoid economic and political pressure, authorities hesitated to carry out evacuations that might turn out unnecessary. The deadly mudflows triggered by the eruption, which killed 23,000 people, travelled several hours after the observed onset of the eruption before they reached populated areas.

After the Soufrière crisis and still more so after the Nevado del Ruiz disaster, it has become a philosophy in volcanology to avoid publicly expressing disagreement and speculation that could create confusion. It is preferred to have a single, relatively small team work on a restless volcano during a crisis, and voice their findings via a single outlet to the public. This practice has been applied during a number of recent volcanic crises, most notably Pinatubo (1991) and Soufrière Hills on Montserrat since 1995 (initially different teams working on Montserrat and expressing different views on the risk caused a high degree of consternation in the population and authorities).

Maybe this helps a bit to understand why the making public of raw data is viewed by many as inopportune. One may disagree about the usefulness of such limitations, but that's the story behind it.

@16 - sorry to go back so far. But the indonesian meteorological station seems to be reporting quakes not shown in the USGS quake lists. I thought the USGS reported quakes from all over the world when magnitudes were greater than 2.5. The latest two 5.2 magnitude quakes aren't listed on the USGS.

Anyone doing research, then, on earthquakes around the world cannot rely on one source, the USGS, for world earthquake information. Must one have to check all the meteorological stations around the world then?

Les Francis (#42)! Hang on! The operant phrase is "quoted as saying". Dr Surono may very well have said that Sinabung was not monitored because it was a Category B volcano and the journalist, either with an axe to grind or wanting to increase his journalistic standing, exchanged "Category B" for "extinct". With some 129(?) active, or Category A, volcanoes to worry about and who knows how many thousand Category B & C volcanoes or volcanic complexes in the country, do you really blame him personally for not watching Sinabung? Since your family "has a hill station holiday house built on a dormant dome only 10ks - line of sight from Sinabung", your apprehension is eminently understandable. Jon Friman's advice (#45) is good advice quote>

Henrik, Another governement official had to make an apology for Surono for misleading the local people into believing that Sinabung would not erupt.

Andiâs statement corrected a previous announcement made by Surono, chief of the Medan-based Vulcanology and Geological Disaster Mitigation Center, who said that local residents did not have to worry about increased activity at Mt. Sinabung.
The mountain was considered ânot a dangerous volcano,â Surono said.

Surono's Satement was made to allay fears to local residents who were complaining of unusual tremor activity emanating from around Sinabung.

There is no point in installing a siesmic monitor at our hill station home. It's only used at weekends and their would be no one their qualified to operate it or interpret any results. Further more there are so many people living around the area any suspicious tremors are immediately reported en masse.

The area around Sinabung is at 1000 metres above sea level. Access roads to the area are narrow, windey and steep. There are hundreds of thousands of people within a 50 kilometer radius. A Large eruption would be chaotic with a large population trying to get out of harms way.

By Les Francis (not verified) on 31 Aug 2010 #permalink

@Boris Behncke, Catania, Italy, If the tremor amplitude is increasing on the sensors around Etna. It would think that means that the mountain is expanding, as the magma system is "boiling" it's way out of the magma pathways inside Etna.

It would be interesting to know where the tremor amplitude is increasing. That is 0.5 - 1Hz, 1 - 2Hz or 2 - 4Hz. This seems to matter when it comes to volcanoes and magma. I am not sure why that seems to be the case.

You already should have seen more steam or gas emission from the area that is about to erupt at Etna in the next few hours. The magma is on it's way out, and it is going to be there soon. When exactly is a good guess.

Fortunately there are organizations like USGS or IRIS that have the policy of making most of the data public, seismic especially. It's thanks to them if I've become interested in seismology and volcanoes in general (by the way, thanks to IRIS and Lurking in post #38 now I'm able to monitor Toba and maybe catch largish explosions of Sinabung).

Sure, keeping data available only to selected few *may* save lives and avoid embarassing situations, but then, sorry if this might sound offensive, don't complain if there's a lack of funding because people.

The closeness and perceived lack of information disclosure, the lack of involvement and discussion among potentially interested amateurs and earth students, all slowly lead to a lack of general interest first from the public and then from funding politicians.

Sorry for the somewhat broken English.

The idiotic bot is back again ("post" #78). It's copied a sentence out of Jon Friman's previous post and added a link which purportedly (I'm NOT clicking to find out) takes you to an emporium for designer handbags. Does US law really allow this kind of offensive - in every sense of the word - marketing?

Like I said previously, disable the "URL:" box and you disable the spammer.

By Henrik, Swe (not verified) on 31 Aug 2010 #permalink

I'm showing [78] as being from Mr. Moho, not the bot.

Maybe the bot has already been clipped.

I don't think US law has much to do with it. This forum could be located on a server at Pitcairn Island and the mechanics would still be the same.

Mr Moho #78: I fully agree with you that the public should be involved much more than is currently being done in many parts of the world, including Italy, where the lack of public outreach is quite conspicuous. I don't know whether making raw seismic data public first will help a lot, though, because it's actually a tremendously complex matter, as I have had the honor to discover when collaborating with experts in volcano seismology in the past two, three years.

So what is needed is constant public outreach not only rendering the data available but also explaining them, thus helping to prevent that everybody makes their own little or big story of the data without really understanding them. This is something many of us here in the INGV are strongly advertising - and to some degree really performing - but the current shortening of funding is not helpful when it comes to communicating with the public. Much of what is being done is voluntary. The reduction in funding is certainly not due to a wrong attitude of the scientists here, but of the government. You can see some of the efforts made in recent months by the INGV on YouTube, where scientists are now regularly giving summaries of the seismic activity in Italy:
Similar contributions are also envisaged for the volcanic activity in Italy.

@Raving #80, the military present in the photo gallery you refer to is actually the Alpine Rescue Service, whose staff is making enormous efforts in saving people from distress on the mountain (unfortunately once in vain) every year, every month, every week. These people are all intensely involved in safety issues at Etna, so it is important to understand that their presence at the inauguration of the new control room was fully justified. But surely, a ceremony like this inauguration always has a political touch to it, like it or not, which is part of the work in a public institution. Unfortunately, the response from the political side is currently extremely dissatisfying.

@Jón FrÃmann #77, there is currently little evidence that significant quantities of magma are at shallow depth in the feeder system of Etna, it rather looks a pressure buildup similar to that of early September 1979, which culminated with a powerful - and unfortunately deadly - phreatic explosion (which is why access to Etna's summit craters is currently forbidden). Very often during recent decades, when the central conduits of Etna are recharging, long before magma arrives at the surface, there are phreatic or phreatomagmatic explosions. "Long before" means, in most cases, weeks to months. Rarely has there been a totally sudden onset of violent magmatic activity during such a phase of recharge. But time will tell, certainly the incrase in tremor amplitude is adding to the suspense ...

Hi, all. Mr/Ms/Mrs. Volcanologist, geologist or something like that. I'm just an ordinary housewife, n I don't have any advance knowledgement like you all. Reading ur discussion, makes me wonder : is there anyone of u ever came to indonesia and stayed here for yrs b4? If u really adore the volcanoes, try it. U'll never know how does it feel to live beyond 'the ring of fire' until u try it urself. I, myself, don't know how many volcanoes r here. You almost couldn't escape from them.Trust me. Every province, every island has their own volcano(es). I will not blame our government for the lack of observations. With hundreds (maybe thousands) of volcanoes around here, there must b priorities. Sinabung, which has dormant about 400 yrs, is not a priority. But merapi (i live in yogyakarta) Which errupted in 2006, IS a priority. Semeru in east java, which throws gas n smoke constantly evry 5-10 minutes IS a priority.So, the only thing that they could do the best is to give us trainings n knowledge how to escape from dangers n how to cope the earthquakes. We have many underground bunkers spread here in evacuate line of merapi. Well, that's all from me. Sorry 4 this inconvenience and to interrupt ur expert discussion.

Hi, all. Mr/Ms/Mrs. Volcanologist, geologist or something like that. I'm just an ordinary housewife, n I don't have any advance knowledgement like you all. Reading ur discussion, makes me wonder : is there anyone of u ever came to indonesia and stayed here for yrs b4? If u really adore the volcanoes, try it. U'll never know how does it feel to live beyond 'the ring of fire' until u try it urself. I, myself, don't know how many volcanoes r here. You almost couldn't escape from them.Trust me. Every province, every island has their own volcano(es). I will not blame our government for the lack of observations. With hundreds (maybe thousands) of volcanoes around here, there must b priorities. Sinabung, which has dormant about 400 yrs, is not a priority. But merapi (i live in yogyakarta) Which errupted in 2006, IS a priority. Semeru in east java, which throws gas n smoke constantly evry 5-10 minutes IS a priority.So, the only thing that they could do the best is to give us trainings n knowledge how to escape from dangers n how to cope the earthquakes. We have many underground bunkers spread here in evacuate line of merapi. Well, that's all from me. Sorry 4 this inconvenience and to interrupt ur expert discussion.

Hi, all. Mr/Ms/Mrs. Volcanologist, geologist or something like that. I'm just an ordinary housewife, n I don't have any advance knowledgement like you all. Reading ur discussion, makes me wonder : is there anyone of u ever came to indonesia and stayed here for yrs b4? If u really adore the volcanoes, try it. U'll never know how does it feel to live beyond 'the ring of fire' until u try it urself. I, myself, don't know how many volcanoes r here. You almost couldn't escape from them.Trust me. Every province, every island has their own volcano(es). I will not blame our government for the lack of observations. With hundreds (maybe thousands) of volcanoes around here, there must b priorities. Sinabung, which has dormant about 400 yrs, is not a priority. But merapi (i live in yogyakarta) Which errupted in 2006, IS a priority. Semeru in east java, which throws gas n smoke constantly evry 5-10 minutes IS a priority.So, the only thing that they could do the best is to give us trainings n knowledge how to escape from dangers n how to cope the earthquakes. We have many underground bunkers spread here in evacuate line of merapi. Well, that's all from me. Sorry 4 this inconvenience and to interrupt ur expert discussion.

Val, thank you for the information. Keep in touch, as most of us don't read indonesian and the google translator is very bad. You say you've got in-ground bunkers-- how big are they? how many can they hold?

Val is perfectly right. With insufficient or even non-existant monitoring of potentially quite dangerous volcanoic systems within Europe and the US, it does smack of hypocrisy to lament the lack of monitoring elsewhere.

Especially since Mr Berlusconi is prepared to pay â¬100 million to obtain the services of a $#â¬Â¤Â£â¬ footballer but refuses to fund the INGV sufficiently. ;)

PS. @#80, 82 - the offensive advertising has been snipped, excellent! Mr. Moho, I do hope you did not for one minute think that I was refering to you... :o

By Henrik on the … (not verified) on 31 Aug 2010 #permalink

@Boris Behncke, Catania, Italy #83, This might simply be a gas pressure build up that you are seeing. But there is also a question if this actually might be old magma that is warming up. I have no way of knowing from Iceland. But I am sure that you will know soon.

But I am expecting that you are already seeing more steam and gas coming from the area that is most likely to erupt in next few hours or weeks already. As the magma is warming and boiling that area already.

@peter van rooij, #71

Wow ... great picures! Tnx

By William M Boston (not verified) on 31 Aug 2010 #permalink

Welcome Val! Thank you for giving us an on-the-ground perspective. I hope you stay with us. BTW, there's no such thing as an "ordinary housewife" :)

I've never heard of underground bunkers in volcanic zones and I'm a little confused as to the rationale behind them due to my own assumptions, the first one being that people would want to move away horizontally rather than down to avoid lava, ash and pyroclastic flows that move...well...down. Are they considered a safe haven of last resort?

By Princess Frito (not verified) on 31 Aug 2010 #permalink

@ Les Francis, #76

Nice map perspective ... by looking at the topology, one can easily envision Sinabung & Sibayak as resulting from the same hot-spot mechanism that gives rise to Toba. An oval of equi-elevation includes all three.

I know that is not a conventionl view, but ...

By William M Boston (not verified) on 31 Aug 2010 #permalink

From the following recent article on Sinabung, it seems that ...

* Yesterday seismic equipment was installed at Sinabung ... but it is not web-capable, and tapes from the seismograph must be delived manually to the main seismo head-quarters for analysis.

* Lava has been flowing, and continues to flow, but is seen as being a good thing by Dr Irwan, in that it will relieve pressure.

* God is somehow implicated in this. :>O


Indonesian to English translation [sort of]

God's power in Sinabung
Tuesday, August 31, 2010 | 6:19 pm

Small Normal Big Sinabung volcanic material spewed into the sky in Karo, North Sumatra, Indonesia, Monday, August 30, 2010. (AP Photo / Roone Patikawa)

TEMPO Interactive, a thin white smoke billowing from the top Sinabung in North Sumatra. Height is 20 meters. Five officers of Volcanology and Geological Hazard Mitigation, Geological Agency, Saturday (28 / 8) noted that all the events from the nearest village.

16:00 to 19:00 o'clock pm, the peak of the mountain shrouded in fog. The next time till 24.00 pm was not observed any smoke from the active crater. "Mountains do not show any signs of increased activity," the report is the fifth officer.

They end up delaying the installation of seismic activity monitoring tool or a seismograph. "We've brought, but the tools have not been installed," said M Hendrasto, head of Volcano Observation and Investigation, Center for Volcanology and Geological Hazard Mitigation.

Visual observation of the apparently less sophisticated. Understandably Sunday (29 / 8) at 0:08 pm, there was a roar from the mountain which is located in Tanah Karo. Four minutes later with the eruption of smoke reaching 1500 meters from the lip of the crater. Volcanology who berkantir in Bandung, a direct change Sinabung type of type B into type A and its status is declared "vigilant".

These eruptions create panic residents and officials. Why not, because state officials North Sumatra symptoms thick smoke and ash that had emerged since Friday night was common. Even Saturday night carried out counseling to residents that the mountain with an altitude of 2460 meters, is safe.

Five officers of Volcanology who came on Saturday just to make observations and coordinate with local governments. Optimism that the mountain will not erupt making them inattentive to install seismographs. New device is installed after the volcanic eruption at a distance of 2.5 kilometers from the summit Sinabung.

The result of volcanic and tectonic earthquake recordings from the same appliance can not be monitored from the volcano observation post in Bandung, like other volcanoes. The tape was sent the manual to the Directorate of Volcanology. Yet another volcano type A, can be monitored directly from the central office in Bandung via satellite.

"Mount Type B is a volcano that has no character in a magmatic eruption," said Surono, Head of Volcanology. Based on the priority threats, the mountain of type B are not monitored routinely. Sinabung addition, other type B mountain is Mount Merbabu adjacent to the Mount Merapi in Yogyakarta. Then Mount Sibayak in North Sumatra, which is adjacent to Sinabung.

Of the 150 volcanoes in Indonesia, the government divided into three types of delam. This classification is based on the standard documentation of the Netherlands since 1600. Type A is a mountain that had erupted after the 1600s the number of 80 units. There are 34 two mountains into type B because the last eruption circa 1600s. The rest is a volcanic type C that there is absolutely no eruptions.

Number of volcanoes in Indonesia because the region is the meeting place of three plates of the world. To monitor the volcano spread across the archipelago, the government makes a priority scale. High visibility with full equipment provided to the volcano type A, type B while the volcano is considered sleep.

This startling sleeping mountain residents, especially to experts. "The pattern of short eruption, less than 24 hours. It is unusual," said Irwan Meilano, researcher and professor of geodesy Bandung Institute of Technology. He suspects the eruption of the possible results of the process Sinabung plate movement since long.

Like when the earthquake in Aceh in 2005, said Irwan, further increasing the activity of a fire in the mountains of Sumatra fault. Sumatra is characterized by the relationship between volcanic activity and the Earth's plates. Almost all the volcanoes are generally lined up on the fault or the fault of Sumatra. "There is a good example of the relationship with the tectonic, volcanic activity," said Irwan who received an honorary doctorate from Japan.

According to Irwan, in Indonesia, many of volcano-like Sinabung. Never erupted dozens to hundreds of years ago, but so far as not active. For example Mount Tangkuban and Mount Guntur in Garut.

Head of Department of Mines and Energy Government of North Sumatra Province, admitted his side had Utunta Kaban convince displaced residents will Sinabung security. Therefore, he said, in the knowledge during this eruption could be said Sinabung anomaly. "This is the power of God."

Irwan explained there is always a period of time long enough to smoke issuing from the mountains and causing earthquakes volcanic eruption. In the case Sinabung eruption, magma probably rose as high as 3-5 kilometers from the magma chamber in the bowels of the earth.

Apparently, Irwan said, there is a fairly strong pressure. "There may be changes in tectonic conditions such as an earthquake that changed the pattern of magmatic," he said. But he did not know about type of explosion and strength because there is no historical record of volcanic eruptions, a distance of 90 kilometers from Medan city.

To confirm the presence or absence and the potential for the next eruption, scientists need to record the seismic records and information on mountain conditions. So far at least, according to Irwan, molten lava continues to come out to this day can be interpreted as a marker will decrease the eruption. Indeed previous eruptions have been open the volcanic rocks that cover the crater hole.

"That's the good news of molten lava," he said. The bad news continues to escape the lava that can freely point to any side of the mountain. It is feared that the lava will go into the river and down to the settlement becomes lava. In addition, there are also potential eruption trigger Sinabung volcanic eruption on nearby.

Fortunately Widyanto | ANWAR SISWADI | SOETANA Monang Hasibuan (FIELD)

Comments (9)

Yes, we do have to believe in what Allah has promised. That God will not give the test to be able to handle his followers as heavy. So be patient and steadfast for the exam is our key to be able menhgadapi all this. My sympathy and empatiku to what happens to people dialmi and Sinabung. We all pray for the safety and return of normal life in Sinabung.

Muhammad Soleh, 8/31/2010 21:08:25 PM
hope these various tests and trials will soon berakhir.smoga my brothers in a mountain wil Sinabang given the fortitude and strength of faith. for the government pengampu, please dong working professionals who, do not let it happen again. at the end of the small people who become victims.

Rini, 8/31/2010 19:38:16 PM
ah, poor soil BGN bangets in North Sumatra karo n berastagi.semoga people who lived there survived two dehc ............!

Miley cyrus, 8/31/2010 19:05:39 PM
sj volcanoes erupted very scary man if doomsday .. How do you repent before its too late

Renteki Joe, 08/31/2010 17:58:11 PM
Sorry aja org karo when ramadan is definitely taxable.

Gilang, 8/31/2010 14:01:09 PM
BMKG weird, less professional aja ....

Dina, 8/31/2010 12:28:00 PM
"They end up delaying the installation of seismic activity monitoring tool or a seismograph." We've brought, but the tools have not been installed, "said M Hendrasto, head of Volcano Observation and Investigation, Center for Volcanology and Geological Hazard Mitigation"

I quoted his statement,,,
Do not wait for us was the victim posted smua new bozz,,,

People karo, 8/31/2010 10:53:15 PM
prhatin contribute to society and seekitarnya tnah karo ..

Sitti Ramlah, 8/31/2010 10:11:09 PM
Where the central government participation ...

By William M Boston (not verified) on 31 Aug 2010 #permalink

@Val (85): I lived there in yogyakarta too when Mt. merapi erupted, and for information, yes there are several underground bunkers near mt. merapi, here is the link:…
apparently, when mt. merapi erupted at 2006, two man found dead inside the bunker, both suffered with severe burning condition. seems that the heat from volcanic materials that buried the bunker makes the bunker becomes a huge 'oven'.

@Adibrata(95): I was told by locals in Kaliadem that the deaths occurred because the bunker door did not shut properly and that the victims would likely have survived otherwise.

Here are two pictures I took of that bunker in 2007 and 2010, respectively. They give a sense of how much material had to be removed to gain access after the pyroclastic flow swept through.

#93 William Boston:
After all, what settings lie beneath Toba to have caused such a tremendous event back that time? Can it be explained by subduction and basta? I'm not implying it will happen again, but I'd like to understand what could have caused such a tremendous blast.

By Renato Rio (not verified) on 31 Aug 2010 #permalink

I've wondered the same Renato. What process or processes explain the very largest of eruptions? It would seem that whereas Yellowstone is powered by a hot spot, plate subduction is the answer in the case of Toba, Long Valley and La Garita, and meteor/asteroid strikes for the Siberian and Deccan traps. Should the Midway-to-Hawaii arc, considering its substantial volume, but not the time and thus distance factors, also be regarded as a VLE? It would seem there is a correlation between duration and violence on the one hand, and composition of the magma on the other, same as with "regular" volcanoes. LIPs relate to Kilauea same as very large calderas relate to Chaiten.

If you make allowances for the time factor, there are similarities between the the recent Fimvörduhals/Eyjafjallajökull eruptions and the behaviour of the "Yellowstone" hot spot. In the case of the former, first primitive, basaltic, magma erupted, then older, more evolved, magma was remobilised and erupted. The "Yellowstone" hotspot has behaved in what to me appears to be a similar manner.

First, "Yellowstone" is a misnomer as it implies a surface-related, fixed geographical location. The surface trace of the hotspot goes back some 17 million years (14-16 million years according to the USGS) through the Snake River Plain to the Columbia Plateau (or Columbia River Basalts). The history of this hotspot ought to be something like this:

Some 25 mY ago, the hot spot on its way up through the astenosphere encountered the subducting (Juan de Fuca?) plate, which at that point was adjacent to the North American Plate and still rather solid, resulting in an uplift and accumulation of primitive magma. The uplift caused the plates to fracture and resulted in the Columbia River Basalts, several million years' worth of accumulated primitive magma reaching the surface in the geologic blink of an eye. The subsequent "remobilisation" of the old plate (and, possibly and partially, the overlying NAP) resulted in more evolved magmas, hence the caldera forming so-called "super-eruptions" of the Snake River Plain to Yellowstone.

In the future (tens of millions of years) as the material of the subducting plate is assimilated into the astenosphere and (partially) remobilised by the hotspot, there will probably be fewer caldera-forming VLEs. Once the subducting plate is completely gone, the surface expressions of the hot spot might even result in a chain of very large basaltic shield volcanoes. (The physical gap as well as the differences in appearance between the relatively speaking smooth Snake River Plain and Yellowstone could indicate a significant change deep below). How does the thought of a chain of 8 - 10 km high Mauna Keas/Mauna Loas stretching from the Dakotas into Ontario 20 mY from now strike you?

Please note that this is SPECULATION by a non-professional with scant knowledge of geology, vulcanology etc and barely meets the criteria of "informed opinion". ;)

PS. Interesting article, William, especially as both officials and general public invoke their god as an explanation of a natural phenomenon, a phenomenon not too distant in our own history.

By Henrik on a fl… (not verified) on 31 Aug 2010 #permalink

A couple of interesting pieces of information in this Jakarta Post article posted seven hours ago (9.28am Sept 1st local time)…

"The eruption of Sinabung is still categorized as âfreaticâ"
(Meaning magma has still not reached the surface.)

"Indonesia is home to 129 volcanoes, comprising 78 Type A volcanoes, 27 Type B and 24 Type C volcanoes."
(Seems to be a very modest appraisal, or?)

By Henrik, Swe (not verified) on 31 Aug 2010 #permalink

@Henrik on a flight of fancy:

Oh I can see it infront of my eyes, 10K high volcanoes covered in date-palms with heards of reindeers and mountain-goats roaming up and down them, and scores of "Old Faithfulls" gushing water vertically out of the shield volcanos!
The combination of the images of Yellowstone and Mauna Loa went avry in my poor brain:)

By Carl on Readin… (not verified) on 01 Sep 2010 #permalink

@Carl on Reading a Flight of Fancy. That's only what's to be expected from over-indulgence in Amanita Muscaria. My doctor recommends one drink a lot of water and the hallucinations should disappear in a day or two.

PS. Did you too see the house-boat pulled by lemmings about a third of the way up? The one with the sign saying "Etna or bust"?

By Henrik drinkin… (not verified) on 01 Sep 2010 #permalink

@Henrik drinking from the tap:

When I studied archaeology a rather famous archaeologist told a story about consumption of amanita muscaria that they did for "purely scientific" purposes before going out clubbing. One esteemed professor smoked it, another ate it raw and the third drank a liquour based concoction of it. The only one (the famous one) who made it to the night-club was tossed out of the night-club after starting to rearrange the dance-floor. He had drunk the amanita muscaria-boose concoction.
A russian guest-lecturer advised us of how they do it nowadays, since you have a tendency to get violently sick before getting the effect (like being hung-over before you get drunk). The trick is to feed a goat with a lot of amanita muscaria and then drinking the urine of the goat, the goat breaks down the parts that make you sick, but leaves the muscimol untouched.

For obvious reasons I've never tried it.

I loved the lemmings, but why are they pink and have the hair-do of Mr T?

By Carl on Amanit… (not verified) on 01 Sep 2010 #permalink

@#103, Carl sky-high -

Where do you think the good piece of advice, "Don't Eat Yellow Snow!" comes from?

By Kultsi, Askola, FI (not verified) on 01 Sep 2010 #permalink

Hi! In the last days we followed your posts about the Sinabung quite attentively because we are directly concerned with the actual developments. We come from Germany and at the moment we are staying in north Sumatra, because we work in Kabanjahe for two months. At the time of the eruption on sunday morning we stayed in Kabanjahe, but for our own security we where brought to Medan on sunday afternoon, which is about 60km away from mount Sinabung.
Now we are staying in a hotel in Medan and watch the developments very closely. Our plan is maybe to move back to Kabanjahe this weekend, given that there are no more bigger eruptions until then. Kabanjahe is about 10km away from mount sinabung and we would stay there until October 5th.
What do you think? Are the local predictions reliable enough, if they decrease the alert status? Or â if they do not decrease the alert status, what would you suggest to do in that case? Staying in Medan is annoying, too â even if we can do some of our work from here, we are not lucky with the situation, because our actual work is to give seminars to social workers in Kabanjahe.
What about the risk when a new eruption happens? Our feeling is that it is not a good idea to go back â but we actually havenât got a clue about volcanoesâ¦

By Nudge and Celly (not verified) on 01 Sep 2010 #permalink

Hello Nudge and Celly!

Our gracious blog-host has moved the entire blog to a new location. Please go there to get the latest news on Sinabung.

Short answer to your question, yes you can trust the authorities there, but... Volcanos are unpredictable, especially those that has not erupted in historical times and are not fully monitored as Sinabung.
Follow the relevant authorities, and heed their warnings and you will probably be safe.

New blog with more updates on Sinabung:

By Carl on Ye Old… (not verified) on 01 Sep 2010 #permalink

Oh - thank for this ionformation and the answer on our question. Then we will post our question in the new blog. See you there!

By Nudge and Celly (not verified) on 01 Sep 2010 #permalink

When my wife first fell pregnant we decided to get online and try to research as much as possible so we knew what was going to happen. There were plenty of decent sources of information, however if you are in australia we don't think anything can compete with bubhub for the sheer amount of information all in one place.

Thing you are talking about made . Nonetheless, consider this, what if you included a little more? What i'm saying is, I dont want to tell you how you can run your site, however what if you added something which could get people's particular attention? Just simply as a video or maybe a graphic or few to have people excited regarding what you mentioned.