Wednesday, 9 October 2013

Iceland: a geographer’s paradise

I recently co-led a 7-day undergraduate field trip to south-western Iceland.  This was my first visit to the country so I was really excited to see the land of fire and ice that I had heard so much about!  One of my motivations for becoming a geographer is my love of the outdoors, thirst for exploration and knowledge of new places and environments, so the field trip element of physical geography has therefore always held a huge appeal for me.  And to date my career has taken me to some amazing places - both within the UK and further afield.  So not surprisingly when I was approached to take part in the student field trip to Iceland, I jumped at the opportunity!

Iceland is a fascinating country - it lies between two continental plates, the Eurasian and the North American, that are constantly pulling away from each other.  The rift valley that this is creating is one of only two places in the world that you can see this happening on the Earth’s surface, the other being the Great Rift Valley of Eastern Africa. You can literally walk between, and next to,  the edge of actual continental plates and on some of the ‘youngest’ crustal surface on the planet.  This geographical rarity alone is reason to visit Iceland but this incredible place has much more has to offer!

Þingvellir: the rift valley in Iceland where the Eurasian and North American continental plates are pulling apart. The photos are showing the edge of the North American plate, with the lower photo looking out over the rift valley towards the Eurasian plate.

Iceland is also located over a hotspot (see the previous blog post by @volcanologist  for more information on hotspots), which is thought to have originally formed the island. This and the rift valley mean that Iceland is tectonically active, as you drive around, the horizon is littered with spectacular volcanoes and relict lava flows are dotted across the landscape.

The volcanic scenery in Iceland: the snow-capped summit of the volcano Hekla, the basalt cliffs at Vik formed from 3 distinct lava flows lying on top of one another, and the lava field from the 1783 Laki eruption (from left to right).

Not only do the volcanoes and related features provide a stunning backdrop, they are of interest to geologists to better understand how and why they erupt and what this means in relation to the inner workings of the Earth.  The rich history of Icelandic volcanic eruptions also provides a fantastic resource for geographers trying to understand the surface processes.  Each eruption deposits a layer of tephra across the ground in affected areas, these are then reburied by subsequent layers of soil through time. The composition, thickness and biota in these layers can tell us a lot about the environmental conditions occurring at the time of deposition (for example we can use the pollen as explained by @DrM_Farrell in one of her earlier blog posts).  The date of  these volcanic eruptions is well documented and, as each eruption has a unique signature, we can identify the date of the tephra layers and as such you can constrain the time periods of the other soil layers using a technique called stratigraphy.  This method has been used to better understand the influence that humans have had on the landscape since settlement in the 9th century, the impact of deforestation and the effect of changing climate on soil formation and erosion.

A soil profile showing the distinctive black tephra layer at the top of the photo.

My main research area is the fluvial environment, so I was really excited to see the amazing braided rivers and waterfalls that Iceland had to offer, and I wasn’t disappointed! The scale of these are far greater than any in the UK and it was amazing to see them.  Below are some photos giving examples of some of the fluvial features we visited. The top row gives some examples from the many impressive waterfalls there are along the southern coast of Iceland. From left to right, these are Gullfoss (translated as Golden Falls), Hjálparfoss (Help Falls) and Skógafoss (Forest Falls). On the bottom row are images of some of the rivers, at either end are examples of braided river systems from the Þórsmörk valley into which the Eyjafjallajökull glacier (sitting on the slopes of the volcano that created havoc to European air space in 2010) drains. The high sediment load in the area creates these fantastic braided channels in the river systems. The middle picture on the bottom row shows the River Skeidará , the different colours represent the merging of water from two different sources, glacially fed water that has a heavy sediment load and fluvial (clearer) water.

As well as flowing water, as you can imagine Iceland also has plenty of frozen water and there are numerous glaciers and ice caps. The northerly location of Iceland -65° latitude mean that winters are cold and dark.   These cold conditions promote glacier formation.  On the field trip we investigated the geomorphological evidence for the retreat of the Skaftafell glacier which included a hike on the glacier ice of the Sólheimajökull glacier to measure the impact of debris cover on the glacier surface.  It was a great thrill for the students to get up close and personal with a real glacier.

Looking up the Skaftafell glacier from its terminus (left image), the glacier walk on the Sólheimajökull glacier (2 right hand images).

Field trips typically consist of long days in the field followed by long nights analysing the data with the students, so although the trip was hard work it certainly didn’t in any way detract from the awe of the place.  Iceland presents a fantastic opportunity to investigate a variety of geological and geographical processes and landforms, and experience incredible scenery.  As an added bonus I was also treated to my first ever viewing of the Northern Lights, as well an Arctic fox up close!

Arctic Fox

So overall I found my field trip to Iceland both exhilarating and exhausting, and I would wholeheartedly recommend Iceland as well worth a visit for anyone.  I’m certainly planning to go back for my own research so watch this space for updates…

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