GeoLog

volcanology

Imaggeo on Mondays: In the belly of the beast

In the belly of the beast . Credit: Alexandra Kushnir (distributed via imaggeo.egu.eu)

Conducting research inside a volcanic crater is a pretty amazing scientific opportunity, but calling that crater home for a week might just be a volcanologist’s dream come true, as Alexandra postdoctoral researcher at the Institut de Physique du Globe de Strasbourg, describes in this week’s Imaggeo on Mondays.

This picture was taken from inside the crater of Mount St Helens, a stratovolcano in Washington State (USA). This particular volcano was made famous by its devastating explosive eruption in 1980, which was triggered by a landslide that removed most of the volcano’s northern flank.

Between 2004 and 2008 Mount St Helens experienced another type of eruption – this time effusive (where lava flowed out of the volcano without any accompanying explosions). Effusive eruptions produce lava flows that can be runny (low-viscosity) like the flows at Kilauea (Hawaii) or much thicker (high viscosity) like at Mount St Helens. Typically, high viscosity lavas can’t travel very far, so they begin to clump up in and around the volcano’s crater forming dome-like structures.  Sometimes, however, the erupting lava can be so rigid that it juts out of the volcano as a column of rock, known as a spine.

The 2004 to 2008 eruption at Mount St Helens saw the extrusion of a series of seven of these spines. At the peak of the eruption, up to 11 meters of rock were extruded per day. As these columns were pushed up and out of the volcanic conduit – the vertical pipe up which magma moves from depth to the surface – they began to roll over, evoking images of whales surfacing for air.

‘Whaleback’ spines are striking examples of exhumed fault surfaces – as these cylinders of rock are pushed out of the volcano their sides grind against the inside of the volcanic conduit in much the same way two sides of a fault zone move and grind past each other. These ground surfaces can provide scientists with a wealth of information about how lava is extruded during eruption. However, spines are generally unstable and tend to collapse after eruption making it difficult to characterize their outer surfaces in detail and, most importantly, safely.

Luckily, Mount St Helens provided an opportunity for a group of researchers to go into a volcanic crater and characterise these fault surfaces. While not all of the spines survived, portions of at least three spines were left intact and could be safely accessed for detailed structural analysis. These spines were encased in fault gouge – an unconsolidated layer of rock that forms when two sides of a fault zone move against one another – that was imprinted with striations running parallel to the direction of extrusion, known as slickensides. These features can give researchers information about how strain is accommodated in the volcanic conduit. The geologist in the photo (Betsy Friedlander, MSc) is measuring the dimensions and orientations of slickensides on the outer carapace of one of the spines; the southern portion of the crater wall can be seen in the background.

Volcanic craters are inherently changeable places and conducting a multi-day field campaign inside one requires a significant amount of planning and the implementation of rigorous safety protocols. But above all else, this type of research campaign requires an acquiescent mountain.

Because a large part of Mount St Helens had been excavated during the 1980 eruption, finding a safe field base inside the crater was possible. Since the 2004-2008 deposits were relatively unstable, the science team set up camp on the more stable 1980-1986 dome away from areas susceptible to rock falls and made the daily trek up the eastern lobe of the Crater Glacier to the 2004-2008 deposits.

Besides being convenient, this route also provides a spectacular tableau of the volcano’s inner structure with its oxidized reds and sulfurous yellows. The punctual peal of rock fall is a reminder of the inherent instability of a volcanic edifice, and the peculiar mix of cold glacier, razor sharp volcanic rock, and hot magmatic steam is otherworldly. That is, until an errant bee shows up to check out your dinner.

By Alexandra Kushnir, postdoctoral researcher at the Institut de Physique du Globe de Strasbourg, France.

This photo was taken in 2010 while A. Kushnir was a Masters student at the University of British Columbia and acting as a field assistant on the Mount St Helens project.

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

 

Imaggeo on Mondays: Life on bare lava

Life on bare lava

There are plenty of hostile habitats across the globe but some flora and fauna species are resourceful enough to adapt and make extreme environments their home. From heat-loving ants of the Sahara to microbes living in the light-deprived ocean depths, through to beatles who brave the bitterly cold Alaskan winter, there are numerous examples of plants, animals and bugs who strive in environments often considered too challenging to harbour life. In today’s post, brought to you by geomorphologist Katja Laute, we feature Vinagrerilla roja, a plant species adept at making difficult terrains its home.

Vinagrerilla roja (Rumex vesicarius) / the Canary Island bladderdock is one of the most successful endemic plants for colonizing new territory in arid and volcanic areas. The photo was taken on the crater rim of the volcano Montana Bermeja (157 m asl.), located at the northernmost edge of the volcanic island La Graciosa. The island was formed by the Canary hotspot and is today part of the protected Chinijo Archipelago Natural Park which shelters endemic and highly endangered species of the Canary Islands.

The volcano Montana Bermeja is composed of red lapilli (pea to walnut-sized fragments ejected during an eruption) which seems to impede any kind of life. But as the photo shows, the bladderdock is actively growing in this apparently hostile environment. That plant life emerges from such a barren and rough volcanic environment seems almost impossible.

Only very few pioneer species succeed and manage to survive in such harsh environments with little to no soil and under an almost desertic climate. Being located on the northern side of the crater rim enables the bladderdock to capture moisture out of the reoccurring Atlantic winds. As these pioneer species grow, their dead leaves and roots will enrich the soil with organic content providing the base for a chain of ecological succession.

By Katja Laute, researcher at IUEM, Brest, France

If you pre-register for the 2017 General Assembly (Vienna, 22 – 28 April), you can take part in our annual photo competition! From 1 February up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

The best of Imaggeo in 2016: in pictures

The best of Imaggeo in 2016: in pictures

Imaggeo, our open access image repository, is packed with beautiful images showcasing the best of the Earth, space and planetary sciences. Throughout the year we use the photographs submitted to the repository to illustrate our social media and blog posts.

For the past few years we’ve celebrated the end of the year by rounding-up some of the best Imaggeo images. But it’s no easy task to pick which of the featured images are the best! Instead, we turned the job over to you!  We compiled a Facebook album which included all the images we’ve used  as header images across our social media channels and on Imaggeo on Mondays blog post in 2016 an asked you to vote for your favourites.

Today’s blog post rounds-up the best 12 images of Imaggeo in 2016, as chosen by you, our readers.

Of course, these are only a few of the very special images we highlighted in 2016, but take a look at our image repository, Imaggeo, for many other spectacular geo-themed pictures, including the winning images of the 2016 Photo Contest. The competition will be running again this year, so if you’ve got a flare for photography or have managed to capture a unique field work moment, consider uploading your images to Imaggeo and entering the 2017 Photo Contest.

Blue Svartisen . Credit: Kay Helfricht (distributed via imaggeo.egu.eu)

When you think of a glacier the image you likely conjure up in your mind is that of bright white, icy body. So why do some glaciers, like Engabreen, a glacier in Norway, sometimes appear blue? Is it a trick of the light or some other phenomenon which causes this glacier to look so unusual?  You can learn all about it in this October post over on GeoLog.

 

‘There is never enough time to count all the stars that you want.’ . Credit: Vytas Huth (distributed via imaggeo.egu.eu). The centre of the Milky Way taken near Krakow am See, Germany. Some of the least light-polluted atmosphere of the northern german lowlands.

Among the winning images of our annual photo contest was a stunning night-sky panorama by Vytas Huth; we aren’t surprised it has been chosen as one of the most popular images of 2016 too. In this post, Vytas describes how he captured the image and how the remote location in Southern Germany is one of the few (in Europe) where it is still possible to, clearly, image the Milk Way.

 

“Above the foggy strip, this white arch was shining, covering one third of the visible sky in the direction of the ship's bow,” he explains. “It was a so-called white, or fog rainbow, which appears on the fog droplets, which are much smaller then rain droplets and cause different optic effects, which is a reason of its white colour.”

Gateway to the Arctic . Credit: Mikhail Varentsov (distributed via imaggeo.egu.eu)

“Above the foggy strip, this white arch was shining, covering one third of the visible sky in the direction of the ship’s bow,” describes Mikhail Varentsov, a climate and meteorology expert from the University of Moscow. “It was a so-called white, or fog rainbow, which appears on the fog droplets, which are much smaller then rain droplets and cause different optic effects, which is a reason of its white colour.” Mikhail captured the white rainbow while aboard the Akademik Tryoshnikov research vessel during its scientific cruise to study the effects of climate change on the Arctic.

 

History. Credit: Florian Fuchs (distributed via imaggeo.egu.eu)

The header image, History by Florian Fuchs, we used across our social media channels was popular with our Facebook followers, who chose it as one of the best of this year. The picture features La Tarta del Teide – a stratigraphic section through volcanic deposits of the Teide volcano on Tenerife, Canary Islands.

 

Find a new way . Credit: Wolfgang Fraedrich (distributed via imaggeo.egu.eu)

Lavas erupted into river waters, and as a result cooled very quickly, can give rise to fractures in volcanic rocks. They form prismatic structures which can be arranged in all kinds of patterns: horizontally (locally known as the woodpile), slightly arching (the harp) and in a radial configuration known as the rosette. The most common configuration is the ‘organ pile’ where vertical fractures form. These impressive structures are seen in the walls of the Gole dell ‘Alcantara, a system of gorges formed 8,000 years ago in the course of the river Alcantara in eastern Sicily.

 

Home Sweet Home . Credit: André Nuber (distributed via imaggeo.egu.eu)

Can you imagine camping atop some of the highest mountains in Europe and waking up to a view of snowcapped peaks, deep valleys and endless blue skies? This paints an idyllic picture; field work definitely takes Earth scientists to some of the most beautiful corners of the planet.

 

Isolated Storm . Credit: Peter Huber (distributed via imaggeo.egu.eu)

In November 2016 we featured this photograph of an isolated thunderstorm in the Weinviertel in April. The view is towards the Lower Carpathian Mountains and Bratislava about 50 kilometers from Vienna. Why do storms and isolated thunderstorms form? Find out in this post.

 

Glacial erratic rocks . Credit: Yuval Sadeh (distributed via imaggeo.egu.eu)

As glaciers move, they accumulate debris underneath their surface. As the vast frozen rivers advance, they carry the debris, which can range from pebble-sized rocks through to house-sized boulders, along with it. As the climate in the Yosemite region began to warm as the ice age came to an end, the glaciers slowly melted. Once all the ice was gone, the rocks and boulders, known as glacial erratics, were left behind.

 

Snow and ash in Iceland . Credit: Daniel Garcia Castellanos (distributed via imaggeo.egu.eu)

Icelandic snow-capped peaks are also sprinkled by a light dusting of volcanic ash in this photograph. Dive into this March 2016 post to find out the source of the ash and more detail about the striking peak.

 

Living Flows . Credit: Marc Girons Lopez (distributed via imaggeo.egu.eu)

There are handful true wildernesses left on the planet. Only a few, far flung corners, of the globe remain truly remote and unspoilt. To explore and experience untouched landscapes you might find yourself making the journey to the dunes in Sossuvlei in Namibia, or to the salty plain of the Salar Uyuni in Bolivia. But it’s not necessary to travel so far to discover an area where humans have, so far, left little mark. One of the last wilds is right here in Europe, in the northern territories of Sweden. This spectacular photograph of the Laitaure Delta is brought to you by Marc Girons Lopez, one of the winners of the 2016 edition of the EGU’s Photo Contest!

 


The power of ice. Credit: Romain Schläppy, (distributed via imaggeo.egu.eu).

The January 2016 header image across our social media was The Power of Ice, by Romain Schlappy. This vivid picture was captured from a helicopter by Romain Schläppy during a field trip in September 2011. You can learn more about this image by reading a previous imaggeo on mondays post.

 

Sea of Clouds over Uummannaq Fjord. Credit: Tun Jan Young (distributed via imaggeo.egu.eu)

The current header image, Sea of Clouds over Uummannaq Fjord by Tun Jan Young, is also a hit with our followers and the final most popular image from Imaggeo in 2016. A sudden change of pressure system caused clouds to form on the surface of the Uummannaq Fjord, Northwestern Greenland, shrouding the environment in mystery.

 

If you pre-register for the 2017 General Assembly (Vienna, 22 – 28 April), you can take part in our annual photo competition! From 1 February up until 1 March, every participant pre-registered for the General Assembly can submit up three original photos and one moving image related to the Earth, planetary, and space sciences in competition for free registration to next year’s General Assembly!  These can include fantastic field photos, a stunning shot of your favourite thin section, what you’ve captured out on holiday or under the electron microscope – if it’s geoscientific, it fits the bill. Find out more about how to take part at http://imaggeo.egu.eu/photo-contest/information/.

 

GeoTalk: Friction in volcanic environments by Jackie Kendrick

GeoTalk: Friction in volcanic environments by Jackie Kendrick

Geotalk is a regular feature highlighting early career researchers and their work. In this interview we speak to Jackie Kendrick, a volcanologist at the University of Liverpool, and winner of the 2016 GMPV Outstanding Young Scientist Award. The occasion will be marked during the upcoming General Assembly, where you’ll be able to listen to Jackie speak in session GMPV 1.1 on the topic of friction in volcanic environments.

First, could you introduce yourself and tell us a little more about your career path so far?

My name is Jackie Kendrick, and I’m a post-doc in volcanology at the University of Liverpool. I studied for an MSci in Geology at University College London, where I conducted my research project in the Rock and Ice Physics Laboratory. This was an insightful experience for me, I had always been passionate about volcanoes, but having the opportunity to work hands-on in a research environment taught me that I wanted to focus on a career an academia.

I then went on to an Internship at the USGS Cascades Volcano Observatory in Washington State (USA), where I worked on processing of seismic data and had the chance to do a huge amount of fieldwork in incredibly varied settings – for example I installed seismometers at Crater Lake, deployed rapid-response monitoring systems (termed spiders!) at Mount St. Helens and performed landslide simulations at a debris flow flume.

I then moved to Munich, where I undertook my PhD in the Department of Earth and Environmental Sciences at Ludwig Maximilian University. During my PhD I was fortunate enough to largely choose the direction of my studies, as such my research focused on lava dome eruptions from an integrated field, monitoring and experimental approach. Lava dome eruptions have always held a huge fascination for me, and their unpredictable behaviour, with rapid changes from effusive to explosive eruptions, continues to enthral the volcanological community. My PhD opened up possibilities I could not have imagined, and I visited breath-taking volcanic landscapes and state-of-the-art laboratories, where I met so many inspirational scientists – I knew the research community was something I could not turn my back on.

Upon completing my PhD in early 2013 I secured a post-doctoral position at University of Liverpool, funded by the European Research Council. During this position I have worked on a great variety of topics, including experimental studies of magma rheology, rock deformation and friction experiments as well as learning new volcano monitoring strategies like infrasound. Importantly, I have also helped design and develop bespoke high-temperature equipment for the rapidly growing Experimental Volcanology Laboratory, which has allowed me to target specific conditions not previously explored, and once again focus my attention toward the behaviour of dome-building volcanoes, which I find so dynamic in both activity and dormancy.

My primary goal in my research is to strive for the integration of multiple strategies, be it geophysics, geochemistry or geodynamics to try to better understand volcanological processes, and that’s something I hope to continue to pursue throughout my career.

During EGU 2016, you will receive the Outstanding Young Scientist Award from the GMPV Division for your work on understanding what role friction plays in volcanic eruptions. For instance, you’ve carried research out which tries to decipher what role the frictional properties of volcanic rocks and ash play in controlling the run-out distances, and associated risk, of pyroclastic density currents. Could you tell us a bit more about your research in this area and its importance?

This is something that I have really just started working on in the last year – it’s a new direction for me and that’s really exciting! To be recognised by the community, in receiving this award, is a great honour, and I do hope that I can continue to push frontiers with the research I undertake in the future.

This new endeavour into pyroclastic flows  developed naturally, logically from work I was doing on sector collapse at volcanoes – where a volcano becomes unable to support its own weight and fails and collapses. We have just recently acquired the capability to study the frictional properties of rocks at high temperature, something which has been really lacking in volcanology previously, and so this opened up a whole realm of possible applications – one of which is looking at the dynamics of pyroclastic flows. Supported by colleagues at University of Liverpool, our approach is to constrain the frictional properties of a range of volcanic materials at realistic temperatures, for example, pyroclastic flows can reach several hundreds of degrees, even as high as 1000oC. The accurately constrained material properties that we get through laboratory experiments can then be integrated into models using accurate topography, which can predict for example, run-out distance, i.e. how far a flow will travel away from the volcano.

This type of study is hugely important at lava dome volcanoes especially, where pyroclastic flows can be triggered by even small collapse events on the lava dome or at lava flow fronts – events that may have no warning at all. Never has this been more apparent than standing on the lava dome at the summit of Mount Unzen (Japan), observing the precipitous drop to the small, vulnerable suburbs of Shimabara town, where tragically, 44 people lost their lives in a pyroclastic flow in 1991.  Hopefully, via our efforts to accurately predict flow dynamics, as well as actively tackling real-time monitoring targeted directly at pyroclastic flows (currently underway at Santiaguito volcano, Guatemala), such tragedies can be avoided in future.

The view down over Mount St. Helens crater from the summit, in the centre the lava dome has grown in the collapse scar from the 1980 eruption. The collapse devastated the proximal land and vegetation, dead trees still float like matchsticks in the calm waters of Spirit Lake and the event left the inner workings of the volcano open to scrutiny. In the background, the glacier-capped Mount Rainier lies dormant. (Credit: Jackie Kendrick)

The view down over Mount St. Helens crater from the summit, in the centre the lava dome has grown in the collapse scar from the 1980 eruption. The collapse devastated the proximal land and vegetation, dead trees still float like matchsticks in the calm waters of Spirit Lake and the event left the inner workings of the volcano open to scrutiny. In the background, the glacier-capped Mount Rainier lies dormant. (Credit: Jackie Kendrick)

These approaches are also pertinent in understanding landslides and sector collapse events too – an interest of mine that was sparked during fieldwork at Mount St. Helens, which suffered one of the most infamous and catastrophic sector collapses ever documented in 1980.

It seems like Mount St. Helens has been a pretty inspirational place for you over the years! Can you tell us more about the work it’s stimulated?

Absolutely- I’ve been lucky enough to visit this spectacular volcano on numerous occasions, sometimes for work and always for pleasure!

My MSci research looked at the strength of rocks that make up the volcanic edifice rocks (usually layered lava flows that give volcanoes their familiar cone-shape), but the real defining moment in my career path was during fieldwork in 2010. During a visit organised between Ludwig Maximilian University of Munich, University College London, University of British Columbia and with the USGS we had the chance to study the crater lava domes up close for almost a week, to conduct thorough structural investigation of the internal lava dome characteristics. The domes, formed during eruptions in 1980-86 and 2004-08 are surrounded by the so-called Crater Glacier, which forms a ring around the domes, and which prevents access by foot – instead, we had to fly in by helicopter and camp in the crater!

There I began to appreciate lava domes for what they are, huge, rigid masses of near-solidified rock that are forced through the crust by buoyant magma below. This is especially true of Mount St. Helens, where the magma during the 2004-08 eruption was already crystallised at a depth of about 1 km and the dome is formed of a series of solid magma spines that rose up during the eruption, like arching whalebacks from the crater floor. These whalebacks are mantled by the products of friction, shear zones with powdery gouge, complex fracture networks and distorted crystals. It became suddenly apparent to me how important frictional processes were during these types of eruption, and how exciting it could be to push my research in a new direction endeavouring to understand it!

So since your career defining visit to Mount St. Helens in 2010, it’s  been your goal to understand how frictional properties come into play in different volcanic scenarios, including the conduit?

Exactly, I’ve always had a passion for new and exciting research directions – and looking at the frictional properties of volcanic rocks in the context of erupting magma was something only touched upon experimentally before.

During an eruption, magma (called lava after it reaches the surface) is carried from the subterranean magma chamber to the surface in a conduit. Some conduit models have proposed a friction criteria to explain certain seismic signals, but parameters were derived theoretically or from friction experiments on other rocks. I started performing friction experiments in 2011. In these experiments 2 cylindrical rock cores are placed end-on, while a load (force) is applied from one end, and the other end is rotated at a desired velocity to create a simulated fault. I’ve looked at the frictional behaviour of volcanic glass, of ash, and of crystalline lavas – and I always try to integrate these studies with geophysical observations of real processes. You can  watch one of these experiments in this video:

Another important aspect is examining microstructures and performing geochemical analysis, to make sure that the experiments recreate elements of natural examples. So far these investigations have led to a number of important findings:

  1. That the heat that can be generated by friction can be immense – just try rubbing your hands together for a few seconds and then imagine this process in magma(!)
  2. Volcanic rocks melt readily under friction – much more rapidly than most other rock types
  3. The heat generated by friction can make the magma degas – volatiles in magma are only stable under certain pressure-temperature conditions, and if rapidly changed the gas will try to escape – we term this thermal vesiculation, and cite it as the driving force of some explosive eruptions
  4. When some lavas melt due to friction, the viscosity (stickiness) of the melt is abnormally high – this melt “glues” the slip zone together (a phenomena called viscous braking) and it can actually control the rate of an eruption.

The list goes on, and there are many applications beyond the conduit, in terms of volcanoes, faults and even material sciences. But even after several years, nothing beats the excitement of seeing a molten magma form between volcanic rocks rubbed together for just a fraction of a second!

The product of our first successful friction experiment at University of Liverpool in 2014 – we created frictional melt in a pair of andesites from Volcán de Colima (Mexico). (Credit: Jackie Kendrick)

The product of our first successful friction experiment at University of Liverpool in 2014 – we created frictional melt in a pair of andesites from Volcán de Colima (Mexico). (Credit: Jackie Kendrick)

We can’t argue, volcanoes are possibly one of the coolest things in the Earth sciences, but what about them sparked your interest and the willingness to dedicate your research to them? In particular, why did you choose this interdisciplinary field at the crossroads between structural geology, seismology and volcanology?

For me, volcanoes hold such intrigue because of the power they possess – the unharnessed raw energy expelled during an eruption is something just fascinating to watch. The fact that they hold the potential to wreak havoc, and that we don’t yet really understand all the processes involved, just adds to my desire to study them, to know them inside and out.

There’s no doubt in my mind that this can be best achieved using an interdisciplinary approach, it’s all about monitoring, detailing and simulating the process. That is, we see something in real-time via geophysics, we simplify the system so that we can explore individual processes experimentally, and then we integrate our findings back into models to see if we can recreate a phenomena – there’s no point explaining one aspect if it can’t tie in all the others.

Fortunately I’ve had a pretty varied background, nonetheless it’s impossible to be an expert at everything – only highlighting the need to work together, to integrate knowledge from different fields in order to start deciphering complex earth processes.

This was the goal of the recent NSF-funded Workshop on Volcanoes 2016, held at Quetzaltenango (Guatemala), near the ever-active Santiaguito volcano, where we shared best practices and methodologies in monitoring and research – something I believe should be at the forefront of our minds moving forward.

To finish, what advice would you give students fascinated by volcanoes wanting to pursue a career in academia studying volcanology?

Well, first off, I’d say go for it! There are so many great post-graduate options nowadays, and you can really go down any route you choose – be it remote monitoring (like InSAR), proximal monitoring (including seismicity, gas measurements), laboratory experiments (such as friction described here) or you can approach volcanology from the social sciences, looking at influences on people and the environment. There are so many ways that you can get into volcanology, and what’s important is drive and passion, more than a specific academic prerequisite.

That said, I would certainly advise getting some experience before committing to post-graduate study, not least to find out exactly where your interests lie! You can get involved in monitoring by volunteering at volcano observatories, or in research by contacting professors and other academics for short internships and research opportunities. If you’re still doing your undergraduate studies, ask around, speak to graduate students to get advice and learn about the options open to you, and if you can, go to conferences, they are excellent for meeting influential people that can help shape your career!

An explosion at the dynamic Santiaguito volcano (Guatemala) in January 2016 – the volcano offers a unique monitoring opportunity as the ancestral Santa Maria volcano sits just a few km away and several hundred meters higher – the perfect vantage point. (Credit: Jackie Kendrick)

An explosion at the dynamic Santiaguito volcano (Guatemala) in January 2016 – the volcano offers a unique monitoring opportunity as the ancestral Santa Maria volcano sits just a few km away and several hundred meters higher – the perfect vantage point. (Credit: Jackie Kendrick)

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