Why Thousands of Volcanologists are Meeting in Portland

By Erik Klemetti | August 15, 2017 1:40 pm
Volcanologists at the IAVCEI meeting in Portland.

Volcanologists at the IAVCEI meeting in Portland.

So, this whole week I’ll be taking part in the IAVCEI meeting in Portland, Oregon. Of course, most people have never heard of IAVCEI, which is an abbreviation of the International Association of Volcanology and the Chemistry of the Earth’s Interior (now you can see why we use the abbreviation.) This meeting is bringing together over 1,200 volcanologists and petrologists (who study magma, not petroleum) from all over world to talk about volcanoes.

We will even be visiting volcanoes during the meeting as almost everyone will be going to Mount St. Helens, Mt. Hood or the Columbia River Basalts during the meeting’s midweek field trip … because geologists love strapping on boots and heading out into the field.

So, why do we (scientists) have meetings like this? The answer isn’t as clear as you might think.

The good things: 

  • First and foremost, it is to interact with your colleagues and community. I’m a volcanologist in Ohio, so you can imagine I don’t run into many people in my field. In today’s world, that is less of an issue because I can reach most collaborators and colleagues easily over email, phone, social media. However, there is much to be said to one-on-one discussions in person to get things done quickly.
  • We also go to get excited about the field. Most meetings are a mix of talks and posters by scientists about their research (you can see mine below). We can hear about the latest developments, many of which aren’t published yet. We can also present our own work to get others interested and (at least for me) to throw some ideas on the wall to see what the community thinks.
  • Make new connections: Sure, you see your longtime friends and colleagues, but meetings are the place to meet on purpose (or by accident) new collaborators.
  • Meetings also allow us geologists to see more of the world. Geology is a field where seeing the rocks is key — and the more you see, hopefully the more you can understand.
  • They are great for science outreach. Many meetings get media attention, so they can help the public realize why studies volcanoes (or whatever your field) is so important. In today’s America, it can’t be overstated how important it is to rebuild public confidence in science.
My IAVCEI poster on my work at the Lassen Volcanic Center in California. This is how I tell fellow volcanologists about my current ideas (and hopefully get feedback).

My IAVCEI poster on my work at the Lassen Volcanic Center in California. This is how I tell fellow volcanologists about my current ideas (and hopefully get feedback).

The bad things (or why we don’t go to meetings sometimes)

  • They are expensive … and in more ways than you think. The meetings themselves cost hundreds to thousands of dollars just to attend. Then there is the travel and lodging in the city. And you have to eat. In the end, a single meeting can easily cost a researcher $5000. Now, where does that money come from? If you are lucky, you might have a research grant or institution that can cover a lot of it. If not, you’re paying out of your pocket to do something vital for your career. This is doubly so for early career people who might not have any many resources from which to draw. If you are a faculty with students, you need to figure out how to help your students attend the meeting as well so they can present their work and start to build needed professional networks. It can be a massive burden, especially for faculty from colleges that can’t (or won’t) fully support attending meetings. So, this can cause people teaching at community colleges, small colleges or from developing countries much less able to participate fully in their field.
  • But that’s not all. Meetings are doubly challenging for scientists with children. What do you do if both parents are attending the meeting? Some organizations offer childcare but at a cost beyond the registration. Some don’t offer any childcare. Very few universities help faculty pay for needed childcare (although I did hear of one that does offer conference care grants, so that’s awesome!) This burden falls strongly onto female scientists who have to skip meetings when their children are young because there are few accommodations for infants at meetings. So, they might miss a few years of conferences, which can be bad if you’re just starting out in the field.
  • People can sometimes misbehave at conferences. For better or worse, there are a lot of events that feature alcohol so inhibitions drop. This means that sexual harassment can be a major problem at meeting, especially when there are major power differences between senior faculty and students. This is unacceptable on so many levels, but the problem persists are people continue to treat female scientists differently than their male counterparts.
  • They are exhausting. For example, the scheduled events at IAVCEI go from 8:30 AM to 9:00 PM every day for 5 days. There are workshops and field trips before and after the meeting. If you’re not someone who revels from social interactions, then they can leave you feeling like you were run over by a bus.
  • They are take a lot of time — to prepare, to travel, to attend. If you are part of a teaching-focussed universities (or a high school teacher), finding time off to attend meetings during the school year can be almost impossible.

Yet, the meetings keep coming because they are the lifeblood of an active scientific community. Can they continue to happen so often at such a high cost? I don’t know, especially in times where scientific support at universities is being cut. Some organizations are starting to stream their meetings online to help with people who can’t attend (although meetings are a big source of organizational revenue). People are even being able to present remotely with digital posters.

In the end, conferences do an excellent job of letting scientists make connections, conceptual or professional or personal. I have many projects that have been borne out of conversations at meetings like IAVCEI. They can be wonderful experiences that make one’s belief in science grow stronger. However, they are also not without their major problems that make it unfair for access and comfort to be a scientist. As long as we can try to continue to solve these issues, we’ll make science stronger.

CATEGORIZED UNDER: Rocky Planet, Science, Science Blogs

Welcome to Rocky Planet!

By Erik Klemetti | August 11, 2017 11:11 am
A view across the San Francisco Volcanic Field to the San Francisco Peaks in Arizona. Taken by me, March 2017.

A view across the San Francisco Volcanic Field to the San Francisco Peaks in Arizona. Taken by me, March 2017.

Welcome to Rocky Planet! This blog is all about the geosciences, from the Earth’s surface down to its core (and even stuff going on off the planet). It is a little tricky to try to describe what you can expect out of Rocky Planet, so why not start with a little about me.

I am Dr. Erik Klemetti (you can see me up in the banner, peering out at you). I’m a professor of Geosciences at Denison University – if you haven’t heard of Denison, we’re a small liberal arts college in the middle of Ohio. My field of specialty is volcanology, which you might admit is a little weird considering that I’m based out of the Midwest … but that’s OK! Geologists love to travel, so that’s what I do to my current field areas: the Lassen Peak area of California, Mt. Hood in Oregon and a little-known but surprisingly large volcanic area near Bend, Oregon called the Tumalo Volcanic Center. I’m into time. Well, that is to say, I’m interesting in how these volcanoes evolve over time and how long it might take them to go from a state of being in “cold storage” to eruption. Interested? You can check out a paper I published in PLOS One about my work at Lassen Peak.

I’m originally from Massachusetts, but my background is what I call “Scandatino” — my mother is from Colombia while my father’s side of the family hails from Finland. So, I drink a lot of coffee, watch a lot of baseball (go Red Sox and Mariners!) and soccer. Oh yeah, and I also almost had a career in radio/music until I zigged and zagged back to geology.

However, I’m betting many of you know me from my previous gig: writing Eruptions for the last 9 years. Eruptions was a blog focused on global volcanism and it was a blast (no pun intended) to write for all those years. You can find the archives of Eruptions here on Rocky Planet.

Times change and so does my blog. Rocky Planet will cover all those geologic wonders that I find fascinating. Don’t worry, it will still be chock full of volcanism, but it is also going to get into earthquakes and rivers and Pluto and why sand is awesome and climate change and everything that tells a story about our planet and beyond. I’m hoping to cover research that might not be blasted across the mainstream media headlines, dispel those over-hyped disaster scenarios, debunk pseudoscientific beliefs in things like earthquake prediction. I will also try to bring in diverse voices across the geosciences – no, we’re not just a field of white men (nothing against white men), but geology is packed with such a panoply of voices.

So, hopefully you’ll make Rocky Planet a regular interweb destination. I’ll be posting a few times a week depending on what the Earth feels like doing. If you need more, follow me on Twitter: @eruptionsblog (yes, I’m keeping the old handle). Leave a comment to say hello and let me know what you’d like to see on Rocky Planet as well or send me an email: rockyplanetblog on Gmail. I’m thrilled to get started here on Discover.

CATEGORIZED UNDER: Rocky Planet, Science, Science Blogs

Volcanic Explosions Rock an Alaskan Island as Etna Rumbles

By Erik Klemetti | May 19, 2017 2:04 pm
An aerial photograph of Bogoslof and Fire Island taken on May 8, 2017.

An aerial photograph of Bogoslof and Fire Island taken on May 8, 2017.Max Kaufman/Alaska Volcano Observatory/University of Alaska Fairbanks

Let’s take a look at some volcanic eruptions going on around the globe this week!

In Alaska, after weeks of relative quiet, Bogoslof had another big explosive eruption. This time, the plume reached 11 kilometers (~36,000 feet) after the Alaska Volcano Observatory noticed an increase in earthquakes at the volcano. Ash from this eruption fell on Umnak Island (almost 100 kilometers away) as it drifted to the southwest. The eruption seems to have been brief, with seismicity dropping quickly after the blast, and Bogoslof now sits on the Orange/Watch volcanic alert. Be sure to check out some crazy pictures of Bogoslof Island, with the multiple craters created by the last six months of eruptions. The spire in the images are the remains of older lava on the island.

At the same time, Cleveland volcano further west in the Aleutians also experienced a small explosive eruption. This one was much smaller than what was noted at Bogoslof, but it still removed all the lava dome that had been forming at the summit of the volcano since March of this year. This is a very typical pattern at Cleveland, where lava domes grow and are then destroyed by explosions likely caused by pressure building up beneath the lava plug.

Over in Italy, Etna continues to be restless, but it has yet to follow up its earliest 11 paroxysms that have occurred since the start of 2017. Dr. Boris Behncke noted that the volcanic tremor at Etna—a sign of magma moving in the volcano—has been rising and falling (see below) but only very small explosions occur from the active vents. It is unclear whether any of this is leading towards a larger eruption with more lava fountains and flows like we saw earlier this year.

Speaking of lava flows, Piton de la Fournaise on Réunion Island had a very brief eruption on Thursday. The island volcano in the middle of the Indian Ocean had small lava fountains and lava flows during the eruption that ended only a few hours after it began. There was a brief seismic swarm before the eruption that allowed some warning that a new eruption was about to begin on the volcano’s Dolomieu cone. However, those earthquakes have not stopped. 

Manam in Papua New Guinea has also been erupting this week. Manam is located on a small island off the coast of New Guinea and has been the location of a long-brewing evacuation and resettlement. However, the PNG government has yet to provide the funds to local residents to move from the volcanically active island to safer locales. Almost 15,000 people will need to be resettled and currently ~25 acres of land have been set aside to help with this transition. However, there has been conflict between the landowners on the mainland and islanders who have tried to move away. This is another example of the issues of long-term volcanic activity and resettlement of people near these volcanoes (much like Sinabung in Indonesia). A delegation of EU officials arrived this week as well to help with the transition process.

CATEGORIZED UNDER: Eruptions, Science, Science Blogs
MORE ABOUT: eruptions, volcanoes

Everyone Stop Freaking Out Over Italy’s Supervolcano

By Erik Klemetti | May 18, 2017 2:27 pm
The Solfatara of Pozzuoli is one of forty volcanoes that make up the Campi Flegrei.

The Solfatara of Pozzuoli is one of forty volcanoes that make up the Campi Flegrei.Getty Images

Yellowstone used to be the favored target of media volcano panic, but now it looks like Italy’s Campi Flegrei has taken that crown for itself. A recent study published in Nature Communications is the latest impetus for headlines like “Italian Supervolcano Might Be on the Verge of Exploding” or “European supervolcano Campi Flegrei ‘could be close to devastating eruption” or “Fears Italian supervolcano Campi Flegrei will blow after scientists spot magma swelling below Earth’s crust.” These make it sound like we’re in for a massive eruption that will forever change the global landscape. But when it comes down to the science of the Campi Flegrei, we aren’t even close.

Before I dive into the new study, let’s talk a little bit about the Campi Flegrei. As I mentioned in my countdown of the “most dangerous” volcanoes on the planet, it might actually deserve some of its foreboding reputation. Now, this isn’t because there are signs an eruption will happen tomorrow, but rather because it’s located in an area of high population (the Bay of Naples in Italy, population >6 million) and it has a history of nasty eruptions. However, its most recent eruption, in 1538, was relatively small and produced a cinder cone called Monte Nuovo. An eruption in 1198 from the Solfatara was likely a steam-driven explosion from the hydrothermal system.

Neither of the most recent eruptions came anywhere close to the two massive eruptions that the caldera has produced: the Campanian Ignimbrite (~36,000 years ago and possibly over 200 cubic kilometers of volcanic debris) and the Neopolitan Yellow Tuff (~15,000 years ago and ~40 cubic kilometers). If an eruption of either of those scales occurred today from the Campi Flegrei, it would be devastating to Europe, burying much of the Bay of Naples region in meters of volcanic debris while sending ash across the continent. However, these are rare events in the overall history of the caldera, so we shouldn’t be jumping to the conclusion that unrest is leading to anything close to these eruptions.


So, why is everybody concerned now? This study by geophysicist Christopher Kilburn and others in Nature Communications is an attempt to change how we think about the signs of a potential new eruption at the Campi Flegrei. Since the early 1950s, there have been three periods of unrest in the caldera, defined by uplift of the Earth’s surface and earthquake swarms. These events are normally attributed to little bodies of magma intruding about 3 kilometers beneath our feet. The unrest since 1970 has been pinned on about 0.03 cubic kilometers of new magma squeezing into the crust (the 1538 eruption, for comparison, released ~0.1 cubic kilometers of lava and debris).

These bouts of unrest have traditionally been interpreted as discrete movements of new magma under the volcano, so as the land rose and earthquakes occurred, magma was injected. Then the uplift stopped, earthquakes subsided and the event was over with no eruption. The magma bodies are small enough that they would cool to solid in a few years. Everything was back to normal. This is par for the course when it comes to “restless calderas.”

But Kilburn and others present a new model that treats all this unrest since 1950 as a continuous event rather than discrete events. This means that as the rocks of the crust start to deform (and break) due to new magma injections, that stress accumulates. At first, the crust will behave like a plastic and stretch when new magma is added. But add enough magma in a short enough timespan—say decades to a century—and the crust stops being so pliable. Instead, it will break, potentially allowing the magma to find a path to the surface and cause an eruption.

Many times, volcanologists look for massive surface changes as a sign of an impending eruption. This is what happened in the 1980 eruption of Mount St. Helens: The volcano grew an enormous bulge from accumulating magma. But Kilburn and others think that large deformations aren’t the only signs of an eruption to come; you might only see a small uplift, but accumulated stress can cause the crust to “snap.” They point to new data from drilling into the Campi Flegrei showing that stress is accumulating in the crust. This could mean that any more unrest—that is, new magma—could push the rocks over a threshold where they will break and an eruption will happen.

The tricky part here is interpreting what kind of an eruption it might be. Most likely, it would look similar to the 1538 eruption of Monte Nuovo or possibly like the 1994 eruption of Rabaul in Papua New Guinea, another caldera that the authors say behaves like Campi Flegrei might. Neither of those eruptions were massive, but they did wreak havoc on the local communities near the volcano. So, if we don’t need as much uplift and seismicity before such as eruption, people who monitor the caldera need to be very careful when they look at signs of unrest.

And for the large population living in and around the Campi Flegrei caldera, knowing when to be prepared to leave will be vital. The last 70 years of unrest, unpunctuated by an actual eruption, means that people could be desensitized to the real hazards of volcanic activity. If the signs of unrest before an eruption are more subtle than what volcanologists and local residents assume will happen, then an eruption could cause more damage as people are left unprepared.

This all being said, this study is just that: a study. It doesn’t really change the state of the Campi Flegrei. What it does is propose a model that suggests that the signs of a new eruption might be more subtle than we think. The crust could be approaching a state where new injections of magma will lead to eruption.

However, this singular study does not say that the next bout of unrest will lead to a eruption. It does not say the eruption will be a massive, devastating explosive eruption. It doesn’t even really say that the area of the Campi Flegrei is in any more peril than ever. It just offers a new way to look at data from the volcano so that we might be better prepared for that next eruption at one of the planet’s most dangerous volcanoes.

[related_video wide-card=”true” post_id=”2036559″/]

CATEGORIZED UNDER: Eruptions, Science, Science Blogs
MORE ABOUT: models, risk, volcanoes

The Crazy Eruptions That Spit Up Diamonds

By Erik Klemetti | May 5, 2017 11:00 am

Getty Images

Diamonds might not be the rarest of geologic materials, but they can be some of the most valuable. Where do we get them all? It takes extremely high pressures to reorganize carbon into diamonds—pressures higher than can easily be mimicked by humans or even created by processes within the Earth’s crust. No, diamonds have to come from the Earth’s mantle, hundreds of kilometers beneath our feet.

But how do those diamonds get to the surface for us to collect (and sell)? The answer lies in some of the oddest and rarest volcanoes on the planet.

Kimberlites are volcanic eruptions that bring material from the depths where diamonds can form. Yet, unlike many geologic processes, a kimberlite eruption could launch rocks from the mantle at over 250 kilometers an hour! Yes, you read right: Kimberlite eruptions might be rocket ships from the Earth’s interior.


Kimberlite magma is what geologists call “ultramafic.” All that means is it is low in silica and high in magnesium (relative to other magma). What makes them cool is that they are likely coming directly from the mantle—that layer of rock beneath the Earth’s crust. Even at its thickest, the crust is only ~70 kilometers thick, but the source of kimberlite magma is likely over 200 kilometers down. So, in kimberlite deposits, we find all sorts of chunks of mantle rocks and minerals, along with chunks of the crust that the kimberlite blasted through (we call these chunks “xenoliths”—foreign rocks).

Kimberlites themselves are best described as “carrot-shaped,” where they widen at the top and narrow at depth until they reach the dyke of magma that was the pathway from their source deep in the mantle. The tops of the pipes might be tens to hundreds of meters wide, but at depth, they are likely only a few meters across.

When they erupt, they produce piles of broken volcanic debris (pyroclastic material) and the cone is filled with kimberlite breccia made from magma, xenoliths, and anything else in the way. They never have lava flows and even the debris isn’t large volume, probably millions of cubic meters rather than the billions (and more) cubic meters of more typical explosive volcanic eruptions.

They aren’t common. Most kimberlites are found in areas of the oldest rocks on Earth known as continental cratons. There are some found outside those cratons (such as the kimberlites of Kentucky and Arkansas) but they are still typically found where the rocks are old. Geologists aren’t too sure why that is, but globally, you find a lot of places where there is old crust like Canada, Brazil, Siberia, South Africa, northern China, and Australia.

[related_video post_id=”2036559″/]

Most kimberlites are old, too, forming from the Proterozoic (between 541 million and 2.5 billion years ago) up to the Cretaceous (79-145 million years ago). However, there are a few places where geologists think youngest kimberlites may have erupted, including the Igwisi Hills in Tanzania that might be only ~10-20,000 years old and the ~30 million-year-old Kundulungu Group on the DR Congo. So, kind of like big flood basalt provinces and komatiite lavas, kimberlites seem to have been more common in the planet’s past.

That doesn’t mean they can’t happen today! What might a kimberlite eruption be like if we had one in the middle of Kentucky (or really anywhere in central North America)?

This is where things get a little more speculative. Considering we’ve never seen a kimberlite eruption, we have to try to back out the events that happen and the timing of the eruption using clues in the rocks—like how minerals shatter, the types of material found in the deposits, and the shapes of the pipes. Really, it comes down to making, well, magmatic soda.

How to Make Diamonds

Kimberlite eruptions likely start when a carbon dioxide-rich magma forms from melting the mantle. That magma could end up with almost 20 percent carbon dioxide by weight, which is much higher than typical magma (that might be only a couple percent). This magma forms 250 kilometers below the surface and is so low in density, it begins to rise rapidly.

As it rises, all the CO2 begins to come out of solution and form a tip on the rising magma. That CO2 foam sneaks into cracks and shatters the rock, allowing for more rising. Behind it follows the kimberlite magma that is still degassing at faster and faster rates, making a magmatic foam that trails the CO2 foam. Really, it is like one big magma soda bottle whose top has been popped. By the time the magma reaches the surface, the foam tip might be 2 to 4 kilometers long moving through that ~1-3 meter pipe.

With all this foam rising through rocks that are under pressure, that dramatic change in stress causes the walls of the pipe to shatter, adding more material to the kimberlite magma as it rises. At times, the kimberlite magma is likely rising behind the CO2 and magma foam at 30 to 50 meters per second. That’s over 100 kilometers per hour.

The gas and foam? By the time it’s close to the surface, it might be moving close to 300 to 600 meters per second … over ~1,000 kilometers per hour! So, the trip from the mantle to the surface might only take one hour to get all the gas, foam and magma to the surface

Now, if you’re on the surface before a kimberlite eruption, this means that you won’t have much in the way of signs that an eruption is going to occur. Once the process starts, you would guess that earthquakes would start to be measured from depth and rapidly rising towards the surface as the magma moves and shatters rock. You would also likely get some tremor associated with the magma moving through the pipe.

However, the rapid nature of the event means that earthquakes might be the only sign until the kimberlite magma and foam is near the surface, when [totally speculative] we could notice an increase in CO2 emissions from the ground or very fast deformation of the area where the eruption will occur. Humans have never experienced at kimberlite eruption, so this would be a whole new world of monitoring and mitigation to prevent casualties if this happens under a populated area.

Once the foam tip of the kimberlite magma reaches the surface, there is going to be a big explosion. All that compressed gas and magmatic foam will now expand rapidly, creating a massive jet of CO2, volcanic debris, random chunks of rock from around the vent, magma and whatever else might be in the way. Depending on how much stuff is mixed it, the plume could rise as fast as over 1 kilometer per second, so it could reach 20-30 kilometers height in a few minutes—so, think something like the eruption of Mount St. Helens in 1980.

However, that rapid decompression creates a blast wave that will travel down as well as up. The wave will propagate back into the pipe at half the speed of sound, creating more degassing of the magma continuing to rise and extending the explosive eruption.

At the same time, the drop in pressure in the pipe causes the walls of the pipe to start to collapse, heralding the beginning of the end. All the magma in the pipe will cool rapidly and solidify, mixing with all the debris to create the mixed up kimberlite breccia. The waves of all these decompression explosions will resonate in the pipe, making a pulsing explosive eruption. However, the whole thing would likely be over in tens of minutes as the wall collapses and the rising magma cools.

The surrounding landscape would be covered in volcanic ash and debris, some made of erupting magma, some made of chunks of mantle and crust xenoliths. The deposit wouldn’t likely be thick, but you could imagine anything within a few kilometers of the vent would be hit with a rain of ballistic bombs and shockwaves from the eruption.

The crater might only be the size of a large sinkhole, but the halo of volcanic debris would extend tens of kilometers. (Sadly, it wouldn’t rain diamonds. They mostly end up in the solidified magma in the crater or dyke beneath it).

After the eruption, the crater, now filled with the porous debris of the eruption, would likely fill up and form a small crater lake. Luckily, kimberlites appear to be monogenetic—that is, they erupt once and are done. Less luckily, they tend to form in clusters, so whatever area experiences the first kimberlite eruption might expect more to come. However, the timing is unknown. Would it be in hours, days, months, years? We don’t know.

In the end, an eruption of a modern kimberlite would be one of the more dramatic geologic events we’ve experienced. In the span of what might be as little as an hour, material from the mantle would be thrown to the surface in a massive explosion that ends as fast as it started. The area around the vent would be devastated, but likely no long-lasting or wide-reaching impacts would be noticed (unless maybe a bunch of kimberlites erupted within days of each other?) Hopefully, it happens far from human populations so we can just enjoy the scientific bounty that would come from such an eruption. Just another way the Earth can make life exciting for those of us who populate the surface.

CATEGORIZED UNDER: Eruptions, Science, Science Blogs

A Costa Rican Volcano Sees Its Biggest Blast in Years

By Erik Klemetti | April 21, 2017 1:57 pm
Mount Etna spews lava during an eruption on April 11, 2017.

Mount Etna spews lava during an eruption on April 11, 2017.Salvatore Allegra/AP

Some updates on current volcanic activity worldwide:

On April 13, Poás in Costa Rica had its largest explosive eruption in years. The explosion was mainly driven by water heated at the summit crater lake/vent area, generating what is called a “phreatic” eruption. Although water turning to steam is the main player, these explosions can still produce plumes that reach over 1 kilometer (~3,200 feet). This eruption at Poás did just that, with plumes 500 to 1,000 meters tall. News reports also mentioned ash fall in the surrounding region, incandescent blocks suggesting magma relatively close to the surface, and boulders 2 meters wide being thrown from the lake vent. (They broke the floor at the Poas visitor’s center!) Passengers on a flight out of San José got quite a view of the eruption. You can watch video of the eruption that was captured by the webcam at Poás. The eruptions have continued, with another blast on April 18.

A video posted by OVSICORI showed the new ash around the Poás crater. Large blocks are evident on the crater floor along with dark gray ash. The view of the summit region shows off the volcano’s multiple crater vents, including the active one and another at slightly higher elevation still filled with a bright blue lake. The OVSICORI scientists have determined that although most of the material that has been erupted so far is old lavas, there is a small percentage of new magma. This means that we are not likely to see these explosions ending soon—so the area around Poás has been closed to all people.

Meanwhile, over on Sicily, Etna continues to have an active 2017. A number of lava flows issued from the New Southeast crater from April 13 to 15, marking the fourth eruptive period for the volcano this year. After a few days, the lava flows started up again while strombolian explosions continued from the summit craters. There is some great time-lapse video showing the lava flows slowly moving down the slopes of Etna. You can definitely see how the flows, even though they are relatively low viscosity for magma, still move more like a pile of rubble being shoved from behind rather than a “river of lava.” Be sure to watch the BBC segment on Boris Behncke, who monitors and documents Etna’s eruptions for the Etna Observatory.

Nishinoshima, 1,000 kilometers south of Tokyo, also erupted this week, sending new lava flows into the sea. This is the first activity at Nishinoshima since November 2015, when two years of eruption ceased after erupting over 100,000 cubic meters (3.5 million cubic feet) of lava. This likely means the island will grow even more, as the 2013–2015 eruption produced a new cone and greatly increased the size of the barren island. That change in size means Japan has also expanded its territorial waters by 70 square kilometers (27 square miles). A fall 2016 expedition found life returning to the island as well.

CATEGORIZED UNDER: Eruptions, Science, Science Blogs
MORE ABOUT: volcanoes

Ranking the 10 Most Dangerous Volcanoes, From Vesuvius to Santa Maria

By Erik Klemetti | April 14, 2017 12:30 pm
The Santiaguito volcano erupting.

The Santiaguito volcano erupting.Martin Rietze/Getty Images

Time to count down some dangerous volcanoes. I’ve gone through what might make a volcano dangerous and how I tried to rank dangerous volcanoes, developing a points system based on population, magma type, volcano type, and past large explosive eruptions. Looking at some recent articles about “dangerous volcanoes,” my ranking comes to some pretty different conclusions. What my ranking boils down to is what volcano has the highest potential for mass casualties based population, style of eruption and potential for large explosive events.

I’ll start with some honorable mentions that fell outside the top 10 (in order of increasing danger): Pululagua (Ecuador), Guntur, Gede-Pangrango and Semeru (Indonesia), Popocatépetl (Mexico), Colli Alban (Italy), Dieng Volcanic Complex and Tengger Caldera (Indonesia), Nyiragongo (DR Congo), and Merapi (Indonesia).

Here are the top 10 (with people living within 30 kilometers and 100 kilometers listed.)

10. Santa Maria, Guatemala (1.25 million/6.2 million): This volcano might be best known for its most active vent, Santiaguito. It has the tendency to erupt explosively with VEI 6 eruption as recently as 1902.

9. Taal, Philippines (2.38 million/24.8 million): Taal is a lake-filled caldera that produced four VEI 4 eruptions in the last 200 years and a VEI 6 eruption only ~5,500 years ago (VEI stands for Volcanic Explosivity Index, and it tops out at 7). Combine that explosivity with abundant water to add to potential explosive eruptions and the large population that could be impacted by ash, and you have a very closely-watched volcano. Taal is monitored by PHIVOLCS, the Philippine volcano monitoring agency.

8. Coatepeque Caldera, El Salvador (1.2 million/6.5 million): Coatepeque is the first “dark horse” in the top 10. It gains points for erupting rhyolite and dacite, both magmas prone to large, explosive eruptions. It is also centrally-located in El Salvador, so a large eruption would likely impact the capital of San Salvador along with the city of Santa Ana. Like Taal, it is a lake-filled caldera, adding to its potential danger by potentially increasing explosivity or mudflows (lahars).

7. Corbetti Caldera, Ethiopia (1.2 million/9.8 million): Now, this is a real under-the-radar volcano. The Corbetti caldera lies within an even older caldera and has produced pyroclastic cones (explosive eruptions of lots of volcanic debris) and obsidian flows, meaning it has the right style of eruption and right composition to potentially experience a big explosive eruption. Not much is known about the Corbetti Caldera, so it is hard to constrain its recent activity. However, it is close enough to Addis Ababa that a large ash-rich eruption might cause quite a humanitarian crisis.

6. Tatun Group, Taiwan (6.7 million/9.8 million): Much like the Corbetti Caldera, Tatun is not a well-known volcano in a country most people don’t associate with volcanism. However, as I wrote about recently, the Tatun Group has all the signs of a volcano that is still potentially active. It is also nestled close to Taipei, so you could imagine an eruption that produced another andesite dome could wreak havoc on the city, mainly from ash fall or mudflows.

5. Vesuvius, Italy (3.9 million/6.0 million): Did you really think Vesuvius wouldn’t be in the top five? The volcano is one of the most dangerous on Earth thanks to its numerous explosive eruptions—and the city of Naples, which is slowly crawling up its flanks. The fact that it doesn’t fall at the top of this list (heck, it’s not even the most dangerous in Italy) betrays how hazardous the other volcanoes might be. Vesuvius has been quiet since 1944, so we’re full into the “complacency” phase where most people don’t remember the last eruption—never a good place to be when 6 million people could be impacted by an explosive eruption.

4. Ilopango, El Salvador (2.9 million/6.7 million): This is another caldera in El Salvador. But unlike Coatepeque, it has erupted in the last 200 years (1880 to be exact). Around 450 CE, Ilopango had a VEI 6 eruption that covered much of El Salvador with ash and brought down Mayan cities across the region. Today, San Salvador sits directly next to the this lake-filled caldera, so the significant danger from this caldera remains after 1,500 years.

3. Aira Caldera, Japan (0.9 million/2.6 million): The population around the Aira caldera might be lower than most of the top 10 volcanoes, but its frequent eruptions (from Sakurajima) and history of large eruptions means it poses a large danger to those 2.6 million people within 100 kilometers. Over the past 10,000 years of the Holocene, the Aira caldera has had a half dozen VEI 4, 5, and 6 eruptions—so don’t be fooled by the constant din of smaller explosions from Sakurajima over the last decade.

2. Michoacan-Guanajuato, Mexico (5.8 million/5.8 million): Here’s the thing about the Michoacan-Guanajuato (M-G) volcanic field: All three population radius values are the same: 5.8 million. Yes, almost 6 million people live within 5 kilometers of this volcanic field that has produced pyroclastic cones generated by explosive eruptions. It has produced numerous VEI 3 and 4 eruptions over the Holocene from 1,400 vents. This means it hasn’t had big eruptions like some of the top 10. But the frequency, potential explosivity, and population in the widespread volcanic area makes it a high risk.

1. Campi Flegrei, Italy (3.0 million/6.0 million): If you’re the sort of person who wants to worry about Yellowstone, maybe you should turn your attention to the Campi Flegrei instead. Not only is it a restless caldera with a more recent history of very large explosive eruptions, it is also smack in the middle of an area with over 6 million people … and it’s partially under the Bay of Naples. All these factors mean that if the Campi Flegrei has a new bout of explosive eruptions, the hazards could exceed those of any eruption in modern history. That being said, the last eruption (Monte Nuovo in 1538) was actually a fairly-benign cinder cone.

Now, this ranking is highly subjective. There can be a multitude of ways to measure danger, so I’m sure people will disagree with this list. Volcanoes like Etna, Cotopaxi, Ruiz, Fuego, and more didn’t make the top 20—mostly because I chose to put emphasis on the style and composition of magmatism.

The big important point here: This list highlights the most potentially “dangerous” volcanoes based on their past behavior (mainly) and the potentially for mass casualties. There will always be volcanoes that might only have a few thousand people living near it that could erupt and kills hundreds of people.

I think of eruptions like El Chichón in 1982 as a great example. The volcano wasn’t even really recognized as a threat until it erupted and killed around 1,900 people. It is unlikely that we can eliminate all volcanic threat, and as the global population grows, the danger posed by volcanoes we can identify as hazardous—and those we don’t recognize as hazardous—will only increase. Funding volcanic research and monitoring along with emergency management organizations is the only way we can hope to protect ourselves from major volcanic disasters.

CATEGORIZED UNDER: Eruptions, Science, Science Blogs
MORE ABOUT: nature, volcanoes

All the Ways To Know If That Volcano Might Kill You

By Erik Klemetti | April 13, 2017 10:30 am
Philippines, Volcano Pinatubo erupting

Getty Images

Dangerous volcanoes are everywhere. But, how dangerous is dangerous or deadliest? Recently, I tried to tackle that notion and codify some ideas about what makes one volcano dangerous when it erupts, while another is merely spectacular. It turns out you can condense a lot of the hazard into a few main factors—and many of them depend on how many people make their homes near these volcanoes.

To start building my list of most dangerous volcanoes, I mined the Smithsonian Institute/USGS Global Volcanism Program database. I found 63 volcanoes with over 10 million people living within 100 kilometers (62 miles)—and 14 of those have erupted in the last 200 years. Gede-Pangrango in Indonesia has over 40 million people living within 100 kilometers of the volcano. And 32 of the 63 volcanoes with 10 million people living within 100 kilometers are in Indonesia.

If we expand this and think about places where at least 1 million people live within 30 kilometers (18 miles), Indonesia is far and away the top, with more volcanoes with 1+ million living within 30 kilometers than the next four countries combined: Philippines, Guatemala, El Salvador, and Mexico.

The number of volcanoes with more than 1 million people living within 30 kilometers, divided by country. Data compiled from the Global Volcanism Program, Smithsonian/USGS

The number of volcanoes with more than 1 million people living within 30 kilometers, divided by country. Data compiled from the Global Volcanism Program, Smithsonian/USGSErik Klemetti

Beyond those population figures, the risk calculation gets trickier: Volcanoes aren’t as binary as “snake venomous, snake not venomous.” To simplify things, I decided to identify the main factors that influence immediate danger from a volcano. One thing many people don’t know: Deaths from volcanic eruptions are low compared to deaths from the consequences of large eruptions (like cooler global temperatures from volcanic aerosols). Here, I’m talking about rapid impacts of eruptions (minutes to days).

I decided that there are four main factors for deciding how dangerous a volcano might be:

Population: We know this one already. I looked at the number of people living within 5, 10, 30 and 100 kilometers of the volcano, then weighted the numbers. As you go out from the volcano, the hazards generally decline. A large population further away might only experience some ash fall or mudflow confined to a river valley—though those can be very deadly if you’re not careful. Populations closer to the volcano bear the full brunt of pyroclastic flows (likely the biggest killer), heavy ash fall, and lava flows (although they aren’t that deadly).

Type of magma erupted: Different types of magma produce different types of eruptions. Sticky, silica-rich magma like rhyolite and dacite can produce explosive eruptions (bad) while silica-poor magma like basalt tends towards lava flows (less bad). So, a volcano that tends to erupt rhyolite and dacite gets a higher score and the converse for basalt.

Type of volcano: Here, I’m getting at the style of eruption as well, but looking at the form of the volcano. Most typically, volcanoes that erupt sticky lavas like andesite and dacite form stratovolcanoes. Sometimes you also get calderas from big explosive eruptions. When you have water involved, you could get more explosive eruptions from silica-poor magma. More points if you have a volcanic form that implies explosivity, fewer points if it suggest more effusive eruptions of lava flows.

How often do eruptions occur: Now, this could be the hardest variable to factor in. You would think that the more a volcano erupts, the more dangerous it is. But this is only kind of true. More eruptions is less good, but they tend to be smaller if there are more. Likewise, fewer eruptions may mean that the eruptions could be larger—like Pinatubo in the Philippines, which hadn’t erupted since 1450 CE until its massive 1991 blast. So, I looked in the Global Volcanism Program database for how many eruptions a volcano has had since 1500 CE (though that record is woefully incomplete for many volcanoes).

The “Big Bang” bonus: This last factor gets at the Pinatubo problem. If I found a caldera-forming eruption in the volcano’s history or a VEI 5+ eruption (i.e., a big bang), then I gave the volcano a few points extra. Helps all those volcanoes that might not erupt often, but have the capability of a very large eruption. However, you never know when a volcano that hasn’t had a big eruption could generate one.

You might have noticed that I ignored the monitoring factor—how carefully groups are keeping an eye on a potentially explosive volcano. It is really hard to quantify, so I decided to ignore it. Hopefully we can assume that none of these volcanoes near large populations would have all their signs of unrest ignored/missed.

Combine these factors in a fancy equation and voila, I generated a list of “dangerous” volcanoes. That list will come in the next post, but just as a teaser, here are some volcanoes that people might be surprised did not make the top 20: Yellowstone (not even close), Hood, Fuji, Rainier, Pinatubo, Nevado del Ruiz, and Cotopaxi. What made it? I’ll reveal that soon.

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CATEGORIZED UNDER: Eruptions, Science, Science Blogs
MORE ABOUT: nature, volcanoes

The ‘Most Dangerous’ Volcano Can Be a Tricky Thing to Pin Down

By Erik Klemetti | April 10, 2017 12:00 pm
Eruption of Tungurahua volcano, an active stratovolcano located in the Cordillera Oriental of Ecuador.

Eruption of Tungurahua volcano, an active stratovolcano located in the Cordillera Oriental of Ecuador.Getty Images

I know you’ve all seen lists like this before: what is the “world’s most dangerous volcano?” Most of the time, that discuss devolves quickly into something about “supervolcanoes,” which is very exciting and all because they can generate massive eruptions. However, they are far from being the “most dangerous” volcano.

But wait, what does “most dangerous” even mean for volcanoes? Are you talking about a volcano that is most active? That would be Kilauea in Hawaii and that’s far from “most dangerous”. What about the biggest volcano? That’s hard to quantify, but maybe it would be Yellowstone … and you’ll see why it is definitely not the “most dangerous.” What about largest eruption? Even that isn’t the best measure of “most dangerous” because some very large eruptions have been in the middle of nowhere.

So, what would I consider “most dangerous?” It comes down to a few key factors:

  1. What is the volcano’s eruptive history? Numerous voluminous explosive eruptions in the last few thousand years is a sign that the volcano has a potential for significant impact on its local environment. There might even be a few volcanoes that produce mostly lava flows that could make this cut. This also gets at the type of volcano and the type of magma erupted. Cinder cones are much less likely to cause wide-spread destruction versus a compound volcano or caldera (Think of this like Volcano — a cinder cone and lava flows, mostly — versus Dante’s Peak — a compound/stratovolcano). Volcanoes that erupt basalt are much less likely to cause an explosive eruption (although not impossible) than a volcano that erupts stickier, more silica-rich lava like dacite or rhyolite.
  2. How many people live close to the volcano? Being “close” is tricky to quantify as the type of eruption will define whether one person who is close at one volcano might not be close at another. In other words, big explosive eruptions with lots of ash that is shot into the atmosphere will impact a wider area (maybe 50-100 kilometers out?) than one that has lots of lava flows (maybe a few to 10 kilometers out?)
  3. How closely is the volcano being monitored? Nothing is more dangerous that something that we don’t see coming.
  4. How well prepared is the area for a major disaster? Nowhere can be 100% prepared, but having plans for evacuations and hazard plans to know where the most impact will be can go a long way to reducing danger.

Really, what I consider as “most dangerous” is a volcano that has the highest likelihood of significant numbers of casualties in an eruption. What is “significant numbers?” Maybe over 500 deaths? So, that got me thinking about deaths in volcanic eruptions over the last ~120 years. And guess what? We’ve gotten better at not being killed in large numbers by volcanic eruptions.

The number of deaths in volcanic eruptions over the last 117 years. The data is culled from a variety of sources.

The number of deaths in volcanic eruptions over the last 117 years. The data is culled from a variety of sources.Erik Klemetti

What is this chart saying? Well, at least to me, there are two things: (1) there is a constant, base level of deaths (fewer an 100 deaths per event) that can be chalked how volcanoes can be unpredictable on the local scale and (2) since the start of the 20th century, large casualty events with >1000 deaths have been going down. Now, there is one exception after 1902: Nevado del Ruiz in Colombia in 1985, where 28,000 people died in volcanic mudflows (lahars), but it might actually be the exception that proves the rule.

Why are deaths down? It is clearly not because there are fewer of us. Population has increased by about 5 billion since 1900, so there should be more people living near volcanoes, especially in places growing quickly like South and Central America along with southeast Asia. It is clearly not that volcanic activity is lower—more or less, the Earth’s volcanic engine keeps chugging along at rates that we’ve seen over the last 10,000 years (at the very least).

My bet is that this is the signal that we’re just getting better at monitoring volcanoes, planning for eruptions and mitigating the results of an eruption. One of the best examples of when the lack of volcano monitoring and hazard plan was most evident was that outlier, the eruption of Nevado del Ruiz in Colombia. In that case, the dissemination of information to people living near the volcano was so chaotic and the disagreement about what the volcano might be next was so prominent that tens of thousands people died. This could have been avoided as there was potentially hours between the start of the eruption and the arrival of the lahars in the towns that were hit, so people could have walked to safety.

It is scenarios like that at Nevado del Ruiz that keep volcanologists up at night. So, when deciding what volcanoes might be more dangerous, you really need to think about both the volcano and people. That’s what I’ll get into as I try to figure out what are really the “most dangerous” volcanoes in Part 2.

CATEGORIZED UNDER: Eruptions, Science, Science Blogs
MORE ABOUT: nature, volcanoes

A Russian Volcano Just Erupted for the First Time in Centuries

By Erik Klemetti | March 27, 2017 2:54 pm
The ash plume from Kambalny on March 25, 2017. The inset image shows the region the day before, with no plume from the volcano and no evidence of ash.

The ash plume from Kambalny on March 25, 2017. The inset image shows the region the day before, with no plume from the volcano and no evidence of ash.NASA, Annotated by Erik Klemetti

This weekend saw a new eruption from Kambalny in southern Kamchatka. Now, the Kamchatka Peninsula is a very volcanically active area, with multiple eruptions going on simultaneously much of the time. There are certain volcanoes that are in almost-constant unrest, like Shiveluch, Kliuchevskoi, and Karymsky. However, Kambalny is not one of the usual suspects for activity.

This changed when a dark grey ash plume was spotted by Earth-observing satellites on March 25. The plume (see above) stretched hundreds of kilometers to the south over the Pacific Ocean and may have reached as high as 8 kilometers (26,000 feet) above sea level. Be sure to check out the NASA Earth Observatory image of the eruption that clearly shows the plume and its shadow. Video taken of the eruption from the ground shows a billowing plume coming from the volcano’s summit. An image taken on March 27 (see below) shows a dark grey layer of ash covering much of the southern tip of Kamchatka and a much weaker plume that is lighter in color. This might suggest the eruption is now much more steam than ash in its column.

The area around Kambalny on March 27, 2017. Dark grey ash is clearly seen covering the snow in the southern part of the Kamchatka Peninsula. The ash plume is much weaker and lighter.

The area around Kambalny on March 27, 2017. Dark grey ash is clearly seen covering the snow in the southern part of the Kamchatka Peninsula. The ash plume is much weaker and lighter.NASA/Aqua/MODIS, Annotated by Erik Klemetti

This eruption was a surprise to the volcanologists that monitor the Kamchatka Peninsula. However, surprises are easy when many of the dozens of volcanoes on the peninsula are far from most people (only ~4,500 people live within 100 kilometers of Kambalny) and most lack any sort of real-time, local monitoring such as seismometers or webcams. This means many of the more subtle signs of an impending eruption, like earthquake swarms, increasing steam-and-gas emissions, or deformation might go unnoticed. This appears to be the case at Kambalny.

At this point, we don’t know if this eruption released any new magma or if it is just an explosion that erupted old, cold material in the vent area of the volcano. If it is new magma, we might expect more explosions, much like what we’ve seen over the last few months at Alaska’s Bogoslof. If it is merely cold rock that was shattered during a large, steam-driven explosion, this could be a one-off event or the opening stages of more explosive eruptions if magma is rising into Kambalny.

Kambalny’s eruptive history is, to say it best, fuzzy. There was a report of an eruption in 1767, but this isn’t confirmed. That’s exactly 250 years ago and could be the minimum estimate for the last time Kambalny saw activity. The biggest source of uncertainty is that lots of small eruptions could have easily been missed since then—at least until we launched satellites to watch the planet.

The last large eruption of the volcano might have occurred as long ago as ~1350. However, Kambalny bears watching as its eruptive history is filled with explosive eruptions and large avalanches. Some small, young-looking cinder cones have also grown on the slopes of Kambalny, which means they haven’t been destroyed by weathering on the peninsula. The take home message here is that Kambalny has the potential to produce some big eruptions, but we just don’t know too much about its behavior.

Currently, KVERT has Kambalny on Orange alert status. Although the volcano isn’t a threat to many people near the volcano (because there just aren’t many anyway), it is a threat to aviation. Some early weather satellite images of the eruption showed contrails from aircraft over the plume material (note: the aircraft are likely ~10,000 feet above the plume) as it drifted out over the Pacific Ocean, which could be bad news if the eruption had gotten more intense and ash reached higher into the atmosphere. Carefully watching these eruptions will help keep people and aircraft safe as they transit the Pacific rim.



CATEGORIZED UNDER: Eruptions, Science, Science Blogs

Rocky Planet

Rocky Planet covers all the geologic events that made and will continue to shape our planet. From volcanoes to earthquakes to gold to oceans to other solar systems, I discuss what is intriguing and illuminating about the rocks beneath our feet and above our heads. Ever wonder what volcanoes are erupting? How tsunamis form and where? What rocks can tell us about ancient environments? How the Earth might change in the future? You'll find these answers and more on Rocky Planet.

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