GeoLog

Tectonics and Structural Geology

Imaggeo on Mondays: Lava highway in Kanaga Island

Imaggeo on Mondays: Lava highway in Kanaga Island

On a rare sunny day, Mattia Pistone (a researcher at the Smithsonian Institution in Washington DC) was able to capture this spectacular shot of Kanaga, a stratovolcano in the remote Western Aleutians, which is usually veiled by thick cloud.

The Western Aleutians form a chain of 14 large and 55 small volcanic islands, belonging to one of the most extended volcanic archipelagos on Earth (1900 km), stretching from Alaska across the northern Pacific towards the shores of Russia.

As part of a team of researchers, Mattia spent three grueling weeks in the isolated region. Being one of the most extended volcanic arc systems on Earth, the Aleutians can shed light on one of the most fundamental questions in the Earth sciences: how do continents form?

The Earth’s landmasses are made of continental crust, which is thought to be largely andesitic in composition. That could mean it is dominated by a silicon-rich rock, of magmatic origin, which is fine grained and usually light to dark grey in colour. However, basaltic magmas derived from the Earth’s upper mantle and erupted at active volcanoes contribute to chemistry of the continental crust. The fact that continental crust bears the chemical hallmarks of both suggests that the formation of new continents must somehow be linked to motion of magma and its chemistry.

Establishing the link between magma generation, transport, emplacement, and eruption can therefore significantly improve our understanding of crust-forming processes associated with plate tectonics, and, particularly, help determining the architecture and composition of the continental crust. The Alaska-Aleutian archipelago is a natural laboratory which offers a variable range of volcanic rocks. The islands present a perfect opportunity for scientists to try and understand the origin of continents.

By collecting samples of volcanic ash erupted at Kanaga and other volcanoes of the Aleutian arc, Mattia and his colleagues are currently investigating the origin of this volcanic ash. Understanding its chemistry allow the team to get a clearer idea of the conditions that were present while the magma was forming and ascending, for example, how much water and iron were present.

The team were based on the Maritime Maid research vessel, and hoped from island to island collecting samples and taking measurements of volcanic activity as part of a large research consortium called GeoPRISMS, funded by the National Science Foundation. The field work was supported by a Bell 407 helicopter and its crew.

Today’s featured image shows an andesitic lava flow erupted in 1906. The volcanic deposits were explored during the field geological mission by Mattia and the team. Kanaga last erupted in 1994. Ash from that eruption was found in the nearby island of Adak. Even at present, there is a highly active system of fumaroles at the summit of the volcano.

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/.

Get involved: become an early career scientist representative

Get involved: become an early career scientist representative

Early career scientists (ECS) make up a significant proportion of the EGU membership and it’s important to us that your voices get heard. To make sure that happens, each division appoints an early career scientists representative: the vital link between the Union and the ECS membership.

After tenure of two or four years, a few of the current ECS Representatives are stepping down from their post at the upcoming General Assembly. That means a handful of divisions are on the hunt for new representatives:

If you are looking for an opportunity to become more involved with the Union, here is your chance! Read on to discover what it takes to be an early career scientists representative.

What is involved?

The ECS representatives gather feedback from students and early career researchers, so that we can take action to improve our early career scientists activities at the EGU General Assembly and maintain our support for early career scientists throughout the year.

ECS Representatives meet virtually (roughly) every quarter and in person at the General Assembly in April. During the meetings issues such as future initiatives, how to get more of the ECS membership involved with the Union and how ECS activities can be improved, are discussed. The representatives are also heavily involved in the running of ECS-specific activities at the General Assembly, such as the icebreaker, ECS Forum and the ECS Lounge.

The ECS Lounge at the 2016 General Assembly. Credit: Kai Boggild/EGU

Within each scientific division, representatives can also take on a variety of tasks, according to their areas of expertise and interest. These can include (but aren’t limited to): organising events for early career scientists at our annual General Assembly, outreach to early career scientists and the wider public through social media or a division blog and much more.

To get more of a feel for what is involved, read this blog post by the outgoing Geodesy Division ECS representative, Roelof Rietbroek, who gives an insight into his experiences while in the role.

As well as giving you the platform to interact with a large network of researchers in your field, being an early career scientists representative is a great opportunity to build on your communications skills, boost your CV and influence the activities of Europe’s largest geoscientific association.

If you think you’ve got what it takes to be the next early career scientists representative for your division, or have any questions about getting involved in the Union, please contact the EGU Communications Officer Laura Roberts Artal at networking@egu.eu.

Application deadlines vary from divisions to division, but new representatives will be appointed before or during the upcoming General Assembly in Vienna (23-28 April). We recommend you get in touch with us ASAP if you are interested in applying for any of the vacancies. You can also keep in touch with all ECS-specific news from your division by signing up to the mailing list.  For more details about how ECS representatives are appointed and the internal structure of individual divisions take a look at the website.

The EGU General Assembly 2017 will bring together geoscientists from all over the world to one meeting covering all disciplines of the Earth, planetary and space sciences. The EGU aims to provide a forum where scientists, especially early career researchers, can present their work and discuss their ideas with experts in all fields of geoscience. The EGU is looking forward to cordially welcoming you in Vienna.

Imaggeo on Mondays: Deep in the Himalayas

Deep in the Himalayas . Credit: Yuval Sadeh (distributed via imaggeo.egu.eu).

The Himalayas: vast, formidable and home to the Earth’s highest peaks. The mountain range stretches inexorably through Indian, Bhutan, Nepal, China (Tibet) and Pakistan separating the Tibetan Plateau to the north from India’s alluvial plains to the south.

India, as we know it today, started life much further south, as an island not far off the coast of Australia. It was separated from Asia (on the Eurasian plate) by the Tethys Ocean, a vast body of water which  wrapped, almost entirely, around the supercontinent Pangea. As the supercontinent started to break up, some 200 million years ago, India began its slow (in human terms, but quite fast geologically speaking) journey north towards Asia.

Moving at speeds between 9 to 16 cm per year (for comparison, human hair grows roughly 15 cm per year), by 80 million years ago, India was located 6,400 km south of Asia. The Tethys was being slowly subducted under the Asian plate and would eventually close (disappear) all together some 30 million years later, when the Indian plate collided against Asia and the Himalayas began to uplift.

The closing and subduction of the Tethyan Ocean, followed by the collision of the two continents produced the Himalayas. The mountain range is divided into six parallel belts, each of which has distinct lithotectonic zones. They are highly complex and represent a long history of tectonic processes and deformation events.

The high peaks of Nepal and China attract a fair share of the limelight, offering thrill seeking adventurers the possibility to get close to (if not scale) the highest mountains on Earth. But lesser known areas of the Himalayas also offer a window into the geological past of the planet and breathtaking scenes for intrepid people too.

Today’s photograph features a valley deep in the Indian Himalayas, and illustrates some geological, geomorphological and other phenomena’s together with a small village that was built inside this glacier curved valley.

 

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/.

Announcing the winner of the EGU Best Blog Post of 2016 Competition

Announcing the winner of the EGU Best Blog Post of 2016 Competition

There is no doubt that 2016 was packed full of exciting, insightful and informative blog posts. An impressive 360 posts were published across the EGU’s official blog, GeoLog, as well as the network and division blogs!

In December, to celebrate the excellent display of science writing across the network and division blogs, we launched the EGU Blogs competition. From a list of posts selected by our blog editors, we invited you, the EGU Blogs readers, to vote for your favourite post of 2016. After a little over three weeks of voting, the winners are finally in!

Without further ado, we’d like to extend a big congratulations to the Cryosphere Blog, who take this year’s crown, with a 58% share of the votes, for their post following the journey of a snowflake! From the water vapour in a cloud to the snowman in your garden, find out what leads to the complex structure you can see on in the image below!

Snowflakes viewed with a low temperature scanning electron microscope (SEM). [ Image Credit : Agricultural Research Service, United States Department of Agriculture via Wikimedia]

All the posts entered into the competition are worthy of a read too, so head over to the poll and click on the post titles to learn about a variety of topics: from the fate of Fukushima Iodine-129 in rain and groundwater, to exploring whether letters of recommendation are the key to the leaky pipeline in academia and how common soft sediment structures like slumps and flames form.

If the start of a new year, with its inevitable resolutions, along with the range and breadth of posts across the EGU Blogs have inspired you to try your hand at a little science writing then remember all the EGU Blogs welcome (and encourage!) guest posts.  Indeed, it is the variety of guest posts, in addition to regular features, which makes the blogs a great read! If you would like to contribute to any of the network, divison blogs or GeoLog, please send a short paragraph detailing your idea to the EGU Communications Officer, Laura Roberts at networking@egu.eu.

 

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