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!
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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.
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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.
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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).
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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.
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| 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.
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| 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!
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| 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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