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GeoEd: Why fieldwork is essential to training the next generation of Geoscientists

3 Apr

Our latest GeoEd article is brought to you by Simon Jung, a lecturer and palaeoceanographer from the University of Edinburgh, who highlights what makes fieldwork a brilliant way to understand Earth processes…

Studying geosciences involves training across a broad range of natural sciences. Only equipped with such background knowledge will students be able to grasp key concepts in the various sub-disciplines that geosciences has to offer. So what’s the best way to get ahold of such knowledge?

A substantial part of the theoretical background in geosciences can be delivered via lectures and/or practicals. Using this standard teaching approach, for example, knowledge of the various rock types and the minerals they contain can be conveyed clearly and effectively. Background information on different soil types, or shapes of rivers, can also be passed on in this fashion.

For something more visual, geological or geomorphological maps can create a great 2D representation of a 3D structure, giving basic insights into the relationship between larger sets of strata or geomorphological features in a given region.

There are, however, important limitations as to the level of understanding students can possibly reach through a classroom-only approach. And these can only be overcome through field training.

Viewing a landscape from an elevated spot – or otherwise suitable location – in the field allows much better comprehension of the processes that have shaped a region. For the first time, truly understanding the nature of the succession of different rock types is an eye-opening and life changing event. Similarly, grasping the role of time in allowing long-term erosion to shape a region can only be attained in the field. A visit to the northwest of Scotland is one way to achieve these goals.

Studying an outcrop in northwest of Scotland. (Credit: Simon Jung)

Studying an outcrop in northwest of Scotland. (Credit: Simon Jung)

Geological and geomorphological research in northwest Scotland has been instrumental in laying the foundations of many crucial concepts in geosciences. The area offers easy access to a unique set of rock sequences documenting Scotland’s early geological history, the explosion of life on Earth, as well as how rivers and ice have shaped the modern landscape. Students from the University of Edinburgh are frequently taken out here, where they are exposed to a huge variety of geological and geomorphological phenomena.

The more specific learning outcomes center around three main areas:

  1. Hands on training in the field helps refining all aspects related to fieldwork (e.g. observational skills, mapping)
  2. Using self-generated field data regarding rock sequences and their 3D orientation allows students to comprehend the long-term geological history
  3. Students also obtain a greater understanding of the role of erosion in shaping the landscape in a region. How? By determining river runoff at a number of locations and making measurements of the sediments being transported

Such excursions allow students to develop an improved understanding of the local geological and geomorphological history of a region.  At a larger scale, they will also develop a more comprehensive view of the processes having shaped the Earth. As the video below documents, this journey is not only educating, but fun too!

By Simon Jung, Lecturer in Palaeoceanography, University of Edinburgh

 

Sniffing out signs of an earthquake

28 Mar

Last year Kate Ravilious was awarded an EGU Science Journalism Fellowship to follow scientists studying continental faults. Now she’s out in Nepal alongside researchers who are working out when the county’s next big quake will be…

Sometimes the best rocks are found in the worst locations. Yesterday I was reminded of this as I watched Paul Tapponnier, from the Earth Observatory of Singapore, and his team tracing one of the most dangerous earthquake faults in the world, right next to a dusty, noisy, dirty and busy main road in southern Nepal. Hooters were blaring, bells ringing and people shouting. Clouds of fine orange dust (from quarrying down the road) coated us from head to toe and under our feet lay the rubbish chucked out of bus and car windows. Glamourous it was not.

But Tapponnier and his team are prepared to hold their noses and get on with the job in hand. They know that these rocks are likely to hold the answers to the puzzle they are trying to solve, and that studying them could eventually help to save many lives.

Chasing charcoal – the key to dating faults. (Credit: Kate Ravilious)

Chasing charcoal – the key to dating faults. (Credit: Kate Ravilious)

In Nepal earthquakes are a fact of life. India is slamming into Asia at a rate of 4 cm per year (pushing up the mighty Himalayan mountain range) and the strain that accumulates in the underlying tectonic plates releases itself periodically in the form of earthquakes. Tremors of magnitude 4 or 5 happen more than ten times every year, but the real worry is the ‘great’ earthquakes – magnitude 8 or more – which Nepal encounters once every few decades.

The last great earthquake – a magnitude 8.4 – occurred in 1934. It  razed around one quarter of Nepal’s capital, Kathmandu, to the ground and killed 17,000 people across India and Nepal. Since then the population of Kathmandu has grown sevenfold and dangerous multi-story concrete buildings have sprung up everywhere. Kathmandu (which happens to be built on jelly-like ancient lake sediments) has risen to an unenviable first position in the world earthquake risk list and scientists estimate that up to one million people could be killed when the next big quake shakes the Himalayan region.

But when and where will this next big  earthquake be? For decades no-one could even locate the fault that caused the 1934 quake, let alone estimate when it might move again. But Tapponnier has an uncanny nose for sniffing out earthquake ruptures, and in 2008 he found the culprit, hidden underneath layers of Nepalese jungle down on the edge of the hot Terai plains in southern Nepal. Since then he has returned every year, to uncover the extent of this massive fault and learn more about how it operates.

Paul Tapponier searching for signs of earthquakes past. (Credit: Kate Ravilious)

Paul Tapponier searching for signs of earthquakes past. (Credit: Kate Ravilious)

And so it was that I ended up standing next to the busy road, near the small town of Bardibas, thanks to a travel grant awarded by the EGU, to learn about the work that Tapponnier and his team are doing.

This year much of the focus of the field trip has been to map out the shape of the land, using a sophisticated LIDAR (Light Detection and Ranging) technology. This sleek silver canister rotates and sends out 150,000 pulses of laser light every second. The reflections are used to build up a high resolution three-dimensional picture of the surface.

Sorvigenaleon Ildefonso, a LIDAR technician  from the Earth Observatory of Singapore, along with Aurélie Coudurier-Curveur and Çagil Karakaş, both post-doctoral researchers at the Earth Observatory of Singapore, have spent the last two weeks gathering as many measurements as possible, from a range of locations (many of which are beautiful and tranquil spots), often working until the light fades and they can no longer see what they are doing. The day I arrive they are hauling the LIDAR and associated equipment from location to location, ignoring the energy-sapping heat, blaring of horns, stink of rubbish and clouds of dust. While I am constantly distracted by what is going on around me, they are all completely focused, setting up their equipment with precision and great care, and recording their measurements meticulously.

Sorvigenaleon Ildefonso setting things up for LIDAR. (Credit: Kate Ravilious)

Sorvigenaleon Ildefonso setting things up for LIDAR. (Credit: Kate Ravilious)

What they are searching for is changes in gradient, not always visible to the naked eye under the thicket of vegetation. Much of the hillside has a step-like appearance, and each of those steps may represent one upward thrust of the earthquake. By using the LIDAR to map out these steps in detail they can work out how many times the fault has moved, and how much land it thrust upwards each time.

Meanwhile, down at the bottom of the hillside Tapponnier and his Nepalese colleague, Som Sapkota, from the Department of Mines and Geology in Kathmandu, are standing in a ditch, searching for miniscule pieces of charcoal in amongst the sand and cobbles of a small outcrop of rock. These incredibly precious fragments (often no bigger than a sesame seed) are the key to dating the timings of the fault movement and working out how often the fault moves on average.

In the pit, picking out charcoal and peering into the past. (Credit: Kate Ravilious)

In the pit, picking out charcoal and peering into the past. (Credit: Kate Ravilious)

It is hot, tiring and often tedious work, but for this group of scientists it is puzzle they refuse to leave unsolved. “We have to study these things, and do it quickly, before the next big earthquake strikes,” says Tapponnier.

By Kate Ravilious, Science Journalist (http://www.kateravilious.net)

Imaggeo on Mondays: Rockscape

24 Mar

A geologist out in the field is often the one doing the mapping, but sometimes you might just find a map while you’re out there. Martin Reiser shares how he stumbled one such stunning feature…

Oxidised and eroded limestone layers, resembling patterns of a geological map. (Credit: Martin Reiser, distributed via imaggeo.egu.eu)

Oxidised and eroded limestone layers, resembling patterns of a geological map. (Credit: Martin Reiser, distributed via imaggeo.egu.eu)

The picture shows colourful marly layers in a Triassic limestone of northwest Albania (Lezhe region). The marly layers have developed intense reddish and greenish colours due to exposure to reduction and oxidation processes (redox-conditions). Subsequent partial erosion has then exposed different levels of these coloured layers and created a pattern resembling a geological map with horizontal layering. Although it might look artificial or even painted, the colours of the rock were really that intense!

The map-like pattern caught my eye when we visited that outcrop during a fieldtrip to Albania in 2011. The fieldtrip was organised by the University of Berlin to study the geology of Albania and specifically focused on the regional tectonic evolution from the Jurassic until the present.

By Martin Reiser, University of Innsbruck

Imaggeo is the EGU’s open access geosciences image repository. Photos uploaded to Imaggeo can be used by scientists, the press and the public provided the original author is credited. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. You can submit your photos here.

Imaggeo on Mondays: Friends in the field

24 Feb

Out in the field you encounter all sorts of wildlife and while mosquitos are the most frequent (and most unwelcome), they generally don’t interfere with your equipment or your data. The same can’t be said for all animals though, and many scientists have to strap their equipment out of reach, barricade it with barbed fences or place it in a relatively indestructible black box. It’s a particular problem when you need to head back to the lab or lecture theatre, and leave your equipment alone to collect precious scientific data remotely.

Animals can also cause a ruckus when you’re on site – after all, what’s more exciting than a geoscientist and their portable laboratory? This is surely the question that played on the minds of these bovine beasties before interfering with a geoelectrical survey, a method used to monitor CO2 storage and map groundwater.

Does it work? (Credit: Robert Supper, distributed via imaggeo.egu.eu)

Does it work? (Credit: Robert Supper, distributed via imaggeo.egu.eu)

While surveying groundwater in Salzburg, Austria, Robert Supper caught a crowd of curious cows taking a closer look at his equipment. “During the measurements on a meadow, we were inspected by a drove of cows, which immediately started to taste electrodes and cables,” he explains.

“On geoelectrical surveys in rural areas, we often encounter an interesting phenomenon: cows or sheep completely ignore us until we finish the installation of cables and electrodes. As soon as we are ready and want to start the measurements, they start to inspect everything, sniff on the equipment, nibble on the cables, stumble over the profile or (worst case) shit on it. If everything was tested correctly by them, they disappear,” Supper adds. Take care when you’re working in a rural area, you might just get some company.

By Sara Mynott, EGU Communications Officer

If you are pre-registered for the 2014 General Assembly (Vienna, 27 April – 2 May), you can take part in our annual photo competition! 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/.

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