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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/.

Imaggeo on Mondays: Concord at midnight

Imaggeo on Mondays: Concord at midnight

The high peaks of the Alps are always awe inspiring, but this midnight shot, captured by Alessandro Lechmann, a PhD student at the Institute of Geological Sciences at the University of Bern, further enhance their fragile beauty. With a warming climate threatening snow availability to even the highest peaks, it has never been more important to appreciate the importance of the glaciers which drape the mountain slopes.

This photograph shows a view from the Jungfraujoch (a saddle in the Bernese Alps, connecting the two four-thousander peaks Jungfrau and Mönch, at an elevation of 3,466 metres above sea level) towards the south-east down the Jungfraufirn (an arm of the Great Altesch Glacier).

Originating amidst three of the most famous mountains of the Swiss Alps (Eiger, Mönch and Jungfrau), this glacier flows southwards towards the Concordiaplatz, where it merges with the Ewigschneefäld and the Great Aletschfirn into the Great Aletsch Glacier. Even today, despite reports of receding glaciers in the Alps, it forms the largest and longest Alpine glacier.

In the countries surrounding the Alps, glacial landforms dominate the landscape. From drumlins, moraines (accumulations of glacial debris) and overdeepenings in the foreland to U-shaped valleys (Lauterbrunnen is a marvellous example) and cirques in mountainous regions. Although retreating at rates not seen previously, these glaciers carved the face of central Europe during the last glacial-interglacial cycles.

The building of the railway to the Jungfraujoch research station started in 1896 and was completed in 1912; an impressive feat considering the limited technology before the First World War. Perched precariously 3500 m above sea level, the research station (known for its prominent sphinx observatory), has contributed significantly   to the understanding of the atmospheric sciences, glaciology and cosmic ray physics.

The ridge which the Jungfraujoch is built on, marks the northern margin of the exposed crystalline core of the Alpine orogeny. Interestingly, this mountain ridge, in addition to being a geological boundary, is also a major watershed. Rain that falls north, flows via the Aare into the Rhine, which eventually discharges into the North Sea. Precipitation on the southern flank and melt water from the Jungfraufirn, on the other hand, joins the Rhone in the Valais valley, that ends up in the Mediterranean Sea. This highlights the importance of Alpine glaciers as a water stores which continue to provide water throughout the year.

By Alessandro Lechmann PhD student at the Institute of Geological Sciences at the University of Bern

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/.

GeoEd: Do as I say… AND as I do

GeoEd: Do as I say… AND as I do

Bridging the gap between student and teacher is not always easy. For students, the educator might seem ‘untouchable’ and inaccessible. A sense exacerbated when assignments are set and they turn out to be new, complex and unfamiliar. In this new installment of our GeoEd column, regular guest blogger Rhian Meara of Swansea University, discusses a simple approach to overcome some of these barriers, which can yield surprisingly positive results.

As teachers, lecturers and professors, it’s easy to forget quite how scary it is to be an undergraduate student. Everything is new – lectures, seminars, practical classes, buildings, cities, and friends. Workloads are increasing and expectations are much higher than at school. We can also be guilty of setting and marking coursework based on our present professional standards including expectations that students will automatically understand what is expected of them. The fallout of this is that students can get overwhelmed, scared to ask questions and plough on despite not understanding what is required of them.

During the last few years, I have taught on a second year module which includes a literature review as part of the continuous assessment. Students attend lectures, workshops and tutorials to learn what a literature review is and how to write their own reviews. However, despite the extensive preparation, there is a communication barrier and a task as simple as a literature review (to the staff) is a monumental and incomprehensible task (for the undergraduates). The students have a tendency to get incredibly hung up on the fact that a literature review is “not an essay” rather than understanding what it actually is and how to complete one.

To counteract this, I have started running an extra tutorial session for my students. In this session, I provide the students with copies my own undergraduate literature review that I completed as part of my undergraduate geology degree at the University of Leicester. The review focusses onto emplacement mechanisms for flood lavas both on Earth and across the Solar System, and was completed during the third year of my degree. In the review, I introduce four models that explain how flood lavas are erupted and transported, critique each model and reach a conclusion as to which model, if any, is most accurate. The majority of the students in the group are physical or human geographers and not avid hard-rock igneous petrologists like I was back in the day, so initially the students are quite intimidated by the subject!

As a group, we then read and discuss the literature review to identify the essential components. These include, but are not limited to, a brief but thorough introduction to the subject, headings and sub-headings, relevant images and maps, appropriate use of references and citations, thorough explanations of the subject material, critical evaluations and conclusions.

Immediate comments from the students included bewilderment at how “professionally written” the work was which led to a useful discussion about academic writing, editing and the appropriate use of jargon. The students also felt that despite their initial intimidation of the subject area, that the review gave them a thorough introduction and explanation of the subject and its associated literature – one of the key aims of a literature review.

At the end of the discussion I asked the students to grade the literature review. As a group the students agreed that the work was a very high quality and merited a 1st class mark (˃70%*). In reality the work had been awarded a 2:1 mark (c. 64%*); however as the work was submitted for a 3rd year module the mark can be translated to a 1st class mark at the 2nd year level. The students were able to see therefore what sort of level they should be aiming at with their own work.

When the students submitted their own literature reviews, I was pleased to see that most of the elements that we discussed had been included into their work. Subjects were clearly introduced and explained, relevant images were used to highlight arguments, ideas were critically discussed and logical conclusions were reached.

Feedback from the students noted that the experience of seeing my own work was incredibly useful as it allowed them to see clear examples of similar work. The students now understand what expectations I have for them in the 2nd year of their undergraduate degree based on my own experiences (do as I say, and as I do!). The tutorial also allowed the students to better understand the process of researching and academic writing.

Getting to see and read through a staff member’s work was very informative. It helped me to understand the level at which to pitch my own work and how the use of appropriate figures, even within essays, could improve the overall quality of the piece. I also found that it broke a perceived wall between the complicated published articles and undergraduate work as it showed how the skills I’m learning now can help with more advance writing in the future.”  (Ben, 3rd year student)

Getting an example of a literature review from my tutor was not only useful as a tool, but felt more personal. Allowing me to ask questions I wouldn’t have, if we didn’t have her work as an example.’  (Tom, 2nd year student)

It was a great help to see a good example of a literature review because I had no idea how to even start! I liked the fact that I could refer back to the example for guidance during the process of writing my own literature review, and I believe that I would have had much worse marks without the possibility of seeing an example beforehand.” (Ffion, 2nd year student)

I ran this tutorial last year for the first time and was pleased with the results. This academic year, the original students who are now in their 3rd year have asked to continue the practice as they write their independent research dissertations. During individual and group tutorials I have shown the students my undergraduate research project on the geochemistry of the Siberian Traps lavas and my PhD thesis on tephrochronology in Iceland. Again, feedback from the students has been positive as they appreciate seeing and comparing with their supervisor’s undergraduate work.

The only negative element of this experience was needing to ensure that students did not re-use the same topics for their own projects as this would be considered as plagiarism. However as previously noted, the academic background of the students somewhat precluded this.

Finally, a piece of advice: if you want to share your work with your students, make sure you develop a thick skin! Once the students get going they are surprisingly harsh during the marking and critiquing element of the tutorial!

By Rhian Meara, Physical Geography and Geology Lecturer at Swansea University

* In UK marking schemes, anything given 70% is considered to be of excellent quality.

GeoEd, is a series dedicated to education in the geosciences. If you’d like to share your teaching and educational experiences, anything from formal classroom teaching, through to outreach project ideas, please do get in touch. We always welcome guest contributions to the blog. To pitch an idea for a post, please contact Laura Roberts Artal (the EGU Communication Officer and GeoLog editor) at networking@egu.eu or take a look at our submission page.

Imaggeo on Mondays: A Fijian paradise

Imaggeo on Mondays: A Fijian paradise

Today’s post is brought to you by Lisa-Marie Shillito, a Lecturer in Landscape Archaeology at Newcastle University. Initially, this photo may seem like any other tropical paradise: lush forests line a meandering river, but there is much more to the forests in the foreground than first meets the eye. Over to Lisa for the details.

I first visited Fiji as an undergraduate student, where I undertook my dissertation fieldwork looking at human versus environmental impacts on marine shellfish size. Although I was there as a geographer, the field site I worked on was an archaeological one – a large prehistoric shell midden (a location for the dumping of waste), and it was here that I first became interested in geoarchaeology..

Fiji is an archipelago containing hundreds of islands, and the largest of these is Viti Levu, measuring 146 by 106 km.

This photo was taken from a helipad on the small island of Qoqo, located in the estuary of the Tuva river, south west Viti Levu Island. Qoqo is a bedrock island comprising two hills connected by a coastal flat and is today surrounded by dense mangrove forest. The mangrove is an important and complex ecosystem that protects inland areas from coastal erosion, and reef areas from sedimentation. They also have an important function in carbon sequestration.

In the distance, you can see the very edges of central mountain range, which forms a north-south division across the island of Viti Levu.

 

By Lisa-Marie Shillito a geoarchaeologist and lecturer at Newcastle University. She blogs about geosciences and archaeology.

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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