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A journey into the Cordon Caulle volcano

A journey into the Cordon Caulle volcano

There is no escaping the fact that one of the perks of being an Earth scientist is the opportunity to visit incredible places while on field work. There is also no doubt that, geologist or not, walking on an active volcano is awe inspiring. Maybe you’ve had the experience of doing so yourself (if so, share your story with us in the comments section, we’d love to hear from you!), but if you haven’t then perhaps this post by Fabian Wadsworth, a volcanology PhD student at the Ludwig-Maximillian Universitat of Munich, Germany and part of the VUELCO project, might give you a feel for what it is like. In the post, Fabian describes his experience of journeying into the Cordon Caulle volcano, in Chile. A regular hiker of the German Alps, Fabian described the difference between climbing the impressive, but well-established trails of the Bavarian mountains to his trip to Chile: “a volcano, is dynamic on a large scale and provides little comfort at all. Hiking in active volcanic landscapes is, for me, more vivid and awakening for this reason.”

Ian Schipper with Jon Castro watching the mouth of the volcano churning out volcanic ash. Image Credit: Dr. Hugh Tuffen

Ian Schipper with Jon Castro watching the mouth of the volcano churning out volcanic ash. Image Credit: Dr. Hugh Tuffen

Dr. Hugh Tuffen, Dr. Ian Schipper and Prof. Jon Castro are volcanologists who study how magmas move, flow and explode on their way up to and over the Earth’s surface. They invited me to join them to Cordon Caulle in January 2014, just two years after it stopped erupting explosively in 2012. This team of researchers had been there in 2011 and in 2012 when it was most vigorously exploding and this post combines photographic reflections on their experience and some from my trip to give you a view of this place and the hike that led us into the volcano’s mouth.

This volcano is unique. It is a type of volcano that produces vast quantities of volcanic glass: obsidian. As well as erupting a huge volcanic cloud, typical of many eruptions, it slowly pushed out a dark tongue of obsidian that was hot enough to squeeze at glacial rates down and away from the source. This kind of eruption is rare and Cordon Caulle is the only time in history that such a phenomenon has been witnessed and studied. Scientists are working to understand how the region can be blanketed by volcanic ash – the result of massive explosions – while this seemingly gentle tongue is pushed out at the same time. In this way, obsidian is one of the most interesting materials to volcanologists and it draws us from all over the world to hike in these wonder-places.

From Puerto Monnt we travelled the 125 km northeast deep into the Andes. The hike to the volcano begins with a long journey through forest up to the highland plateaus. In 2012 this forested land was densely covered in ash from the volcano, Hugh told me, but by 2014 had fully recovered its lush green. From the plateau, the Andes unfold before you and make the many hours hiking feel insignificant. We carried our equipment as well as water, food and sleeping gear ready for a week or more spent in the shadow of the lava. In 2012, the noise of the eruption was intense and could be heard for kilometres around. By 2014-2015, all was quiet except for the buzzing of horseflies and the occasional creek from the heavy glass lava that still crumbled its way over the sand.

The forest land on the hike up in 2012. Hugh remembers the ash filling his hair and covering everything. Image Credit: Dr. Hugh Tuffen

The forest land on the hike up in 2012. Hugh remembers the ash filling his hair and covering everything. Image Credit: Dr. Hugh Tuffen

All around are the dunes of the highland plateaus, ribbed with rainwater gullies and patches of ice, which quench the thirst of hardworking volcanologists.

The dunes of the highland plateaus light up in the low sun. Image Credit: Dr. Hugh Tuffen

The dunes of the highland plateaus light up in the low sun. Image Credit: Dr. Hugh Tuffen

Walking from site to site is hard because the ash-laden sand is soft and sometimes you sink deep. Boots fill with pebble-sized volcanic shards that litter the ground from the last eruption. The distances are also deceptive. The lava, this slow-moving lava flow of glass, is almost forty meters high and many kilometres wide. We made basecamp at one end of the lava and each day hiked to places of interest, sometimes for hours, around the plateaus.

Hugh returned in 2015 yet again with Mike James and student Nathan Magnall and walked between slivers of cloud and tongues of glassy lava. Image Credit: Dr. Hugh Tuffen

Hugh returned in 2015 yet again with Mike James and student Nathan Magnall and walked between slivers of cloud and tongues of glassy lava. Image Credit: Dr. Hugh Tuffen

Starting before dawn, we took one day to set off for a place no one has seen before. We wanted to climb into the mouth of the volcano; into the vent from where the lava was being pushed out back in 2011 and 2012. No one has been into such a place before – the source of obsidian – and we thought that some of the observations we could make would hold a key to the puzzle of these eruptions. We hiked for hours around the great lava flow and to the back side of the vent area. We put on our gas masks to filter some of the still-circulating toxic volcanic gases and particles and we pulled our hats down against the fierce sun. We climbed the cone to the top and peered down into the vent area itself. From that vantage point we circled down the cone’s rim and into the vent proper. From there, gazing back up at the inner walls of the volcano, Hugh, Jon and Ian remembered watched this area explode and writhe just a few years before at the height of eruption. With an uneasy feeling, we set about learning what we could from the rocks and glass at the source of obsidian on our Earth’s surface.

Snatching our hard-won science, we returned to camp only after dark, hungry and thirsty and shared the small celebratory whisky ration we had brought with us. This day, inside the volcano, will remain among the most vivid in my life. And now, back in Munich, I can readily recall the sulfur smell and shine of the glass in that place.

Hugh, Ian and Jon will no doubt continue to return to this enigmatic place to learn more each year and will listen out for the next time obsidian erupts. Nathan Magnall has recently embarked on a PhD project focused on unveiling more of the mysteries of this place and Tuppence Stone, Toby Strong and Christiaan Munoz Salas, who joined Hugh in January 2015, filmed for the forthcoming BBC2 Patagonia series. You can also watch Hugh talk about Cordon Caulle in the video below too – skip to minute 13:00.

The poetry of the place should surely draw people from all disciplines to walk on those new stones – something I emphatically encourage you to do.

By Fabian Wadsworth, PhD Student Ludwig-Maximillian Universitat.

This post was originally posted on the Yetirama Blog. For the original post, please follow this link. We are very thankful to Dr. Hugh Tuffen for the use of his images in this post.

 

Imaggeo on Mondays: Moulin on the Athabasca Glacier

Moulin . Credit: Stephanie Grand (distributed via  imaggeo.egu.eu)

Moulin . Credit: Stephanie Grand (distributed via imaggeo.egu.eu)

The Athabasca Glacier is located in Jasper National Park, in the Canadian Rockies. It is the largest of seven named distributary glaciers carrying ice away from the Columbia Icefield, the largest icefield in the Rocky Mountains. This picture shows a summer meltwater stream running on the surface of the ice disappear in a moulin – a vertical shaft forming part of the glacier’s internal plumbing system. After entering the moulin, the meltwater may flow through englacial streams before reaching the bottom of the glacier, where it forms a glacial deposit known as a kame (see this video for a description of kame formation processes filmed on location at the Athabasca glacier).

Easily accessible from the highway, the Athabasca glacier is one of the most striking places to observe first-hand the effects of climate change. Warmer temperatures have caused an acceleration of ablation processes such as surface melting and erosion, as shown in this picture. The toe of the glacier is currently retreating between 10 and 25 m each summer and the surface of the glacier is dropping down by more than 5 meters per year. It is expected that the Athabasca glacier will disappear completely within a generation.

Collectively, glaciers in Western Canada and Alaska are estimated to lose 20 to 30 per cent as much as what is melting annually from the Greenland Ice Sheet, compounding disruptions in ocean circulation patterns and global sea levels. The disappearance of these mountain glaciers also has implications for hydropower generation capacity and fisheries.  ​

By Stéphanie Grand, Lecturer at the Institute of Earth Surface Dynamics at the University of Lausanne

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: The organisation of a river system

Imaggeo on Mondays: The organisation of a river system

The picture shows the Elbe Rivervalley, one of the major rivers of Central Europe. It was taken from the Bastei Bridge close to Rathen, which towers 194 meters above the Elbe River in the state of Saxony in the south-eastern Germany. This region belongs to the national park known as Saxon Switzerland. Together with the Bohemian Switzerland in the Czech Republic, the Saxon Switzerland National Park forms the Elbe Sandstone Mountains, which represents the greatest cretaceous sandstone erosion complex in Europe and is popular with tourists and climbers.

The Elbe basin covers the largest area in Germany (65.5 %) and the Czech Republic (33.7 %). The smaller parts of the basin lie in the Austria (0.6 %) and Poland (0.2 %). It starts in the northern Czech Republic at an elevation of about about 1400 meters above sea level and flows via Bohemian, Germany, and into the North Sea at Cuxhaven. Therefore, the Elbe river system connects four countries as well as large German cities such as Dresden, Wittenberg, Magdeburg and Hamburg.

The sandstone of the Elbe Mountains was formed by accumulation of sands during a marine regression – a process where previously submerged seafloor becomes exposed due to receding ocean waters – (Cretaceous sea) millions of years ago. The varying sandstone formations that make up the mountains represent variations in pressure regime, horizontal structure and fossil content. After the marine regression, the developed sandstone formations were uplifted. The uplifted sandstone formations have been shaped by subsequent chemical and physical erosion and biological processes acting on the rocks. Moreover, the water masses of the Elbe River formed the valleys and streambeds. Therefore, the current state of the landscape of the Elbe Sandstone Mountains is characterised by the changes between plains, ravines, table mountains and rocky regions with undeveloped areas of forest. Human activity also plays an important role in the shaping of the highland region’s landscape as it is affected by settlements, tourisms and climbers.

The image illustrates how the interplay between long-term processes, such as geology, tectonic history, geomorphology, climate, biology and human influence shape landscapes.

By Tatiana Feskova, researcher at the Helmholtz Centre for Environmental Research.

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: Tombstones Mountains

Imaggeo on Mondays: Tombstones Mountains

This week’s Imaggeo image is brought to you by one of our network bloggers, Matt Herod. Of the image, Matt said ” this particular one is one of my all time favourites. I have even blown it up and hung it on my wall at home,” and we couldn’t agree more; this Canadian landscape is breathtaking. Dive into this post and let Matt take you on a tour of the hydrology, archaeology and volcanic history of the Tombstone Mountain Range.

The Yukon Territory in the fall is a wonderful place and may be among the most beautiful on Earth. As the days shorten the colours become more vibrant and the grasses and shrubs transform. Combine this with the stark and rugged nature of the landscape and you have a potent combination that begs to be explored and photographed.

The subject of this photo is the Tombstone Mountain Range just north of Dawson City, a world heritage site famous for its gold rush, the Sourtoe Cocktail and the funnest casino I have ever been to. The Tombstones constitute the headwaters of the North Klondike River which flows at the base of the valley in the photo and eventually meets up with the larger Klondike River and then joins with the Yukon River at Dawson. Hydrologically the Tombstones mark a continental divide and the transition from southern flowing rivers to northern ones takes place nearby as the many of the rivers just slightly to the north feed into the Peel River and eventually the mighty Mackenzie. A colleague of mine recently concluded a project on the North Klondike measuring the groundwater discharge and chemistry of the river over several years to understand the water sources and the effect of permafrost on the local hydrology.

Indeed, at the base of the valley there is a groundwater discharge point that builds up every winter into a large, layered sheet of ice called and aufeis. As the warmer groundwater continues to discharge throughout the winter it freezes when it meets the cold air forming the aufeis. These structures are often seen at groundwater discharge points in the far north.

The Tombstones themselves, named after the really pointy mountain in the background, are geologically very interesting. Indeed, this relief was created by igneous intrusions during the Cretaceous period. More recently, alpine glaciations shaped the terrain giving rise to a suite of interesting geomorphological and permafrost structures.

The region also has a fascinating archeological heritage and is home to over 70 sites dating back ~8000 years to the Holocene period and some of the earliest human incursions into North America via the Bering land bridge.

This photo was taken in August 2012 on my way up the Dempster Highway. I was collecting water samples for iodine-129 analysis and stopped off in the Tombstone Territorial Park for a sample.

By Matt Herod, researcher at Department of Earth Sciences at the University of Ottawa in Ontario, Canada.

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/.

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