Landing into Keflavik airport has become a familiar sight, as the vast flat expanse of moss-covered lava flows stretches out into a horizon of cold grey clouds as we approach the runway. This is my ninth trip to Iceland, and for this trip we are sampling from various sites in the northeast – some old, some new. Our key target as always is Kverkfjoll – a dormant volcanic caldera that peeks out from the northern margin of Vatnajokull ice cap. Iceland is often referred to as ‘the land of ice and fire’, and the geothermal environments at the summit of Kverkfjoll epitomise this name. Here, scattered clusters of small fumaroles – which vent hot volcanic gas – interact with overlying ice and snow to produce localised and short-lived pools of geothermal meltwater, which provide a haven for microbes within an otherwise remote and frozen environment. These environments provide a fascinating analogue to hydrothermal environments on early Mars. Until we get there however, there are a few other places to stop off at and explore first.
Our field team this year typifies the multidisciplinary collaboration that makes astrobiology such a unique and fascinating area of research. I’m the only geologist this time, and I’m joined by Charles Cockell – microbiologist and director of the UK Centre for Astrobiology at Edinburgh, Matt Gunn – a physicist and all-round instrument man from Aberystwyth University, and PhD student Mark Fox-Powell – microbiologist and essential field lackey. Together we will be sampling sediments and geothermal environments, and also conducting the first field tests of a prototype Spectral Imager – affectionately named ‘SPECI’ on Mars-analogue rocks and soils.
The first few days are spent actually getting to Kverkfjoll – it sits slap bang in the probably the most inaccessible part of Iceland, sandwiched between Europe’s biggest glacier to the south and an immense volcanic desert to the north. While inconvenient, this remoteness is part of what makes Kverkfjoll such a special place to explore the relationship between volcanism and life – up here there is very little interference from anything more complex than a microbe. On our way our first stop is a re-visit to Namafjall for some SPECI testing. Matt and I came here last year on a trip led by Jennifer Harris from Birkbeck to test a field prototype of the ESA ExoMars rover Panoramic Camera. SPECI’s first ever field test is conducted on one of the same targets we used last year:
After a few hours in the sunshine watching Matt and SPECI do all the work, we venture on to Karahnjukar and the impressive Hafrahvamma- and Dimmugljúfur 200m deep canyons. Years of fluvial incision into the bedrock has cut through to reveal spectacular rock exposures, including some nice-looking sediments. These sediments are what we are after, as they provide an analogue to sediments on Mars that originally formed from basalt – the dominant material the Martian crust is made of. After some precarious scrambling we finally reach the imposing canyon floor.
Once safely (sort of..) at the bottom of the canyon, Dimmugljúfur had one more obstacle to throw at us before we could reach our sedimentary exposure. Thankfully, Mark braved the icy waters of the river Jökulsá – now fortunately much smaller since the construction of the Karahnjukar dam upstream – and is able to reach the sediments. It’s at times like this when you wonder whether field geology is less of a science and more of an excuse to scramble about places normal people would think twice about…
Happy with our sedimentary haul we venture onwards further south and east to Kverkfjoll, where we are staying for 10 days. The weather is typically bad at Kverkfjoll, so we expect that maybe only half of those days will actually involve fieldwork. It’s a long rocky drive to Kverkfjoll, which takes us across volcanic sands, glacial rivers, recent lava flows, and older volcanic mountains. Our mighty car is a specially modified Nissan Patrol Arctic. It’s old – it even has a tape player and a faux wood veneer interior – but its tough and reliable and gets us there in one piece. Unfortunately the nice sunny weather of the past few days has turned all our milk, yoghurt, and other dairy produce distinctly cheesy. There are no shops now until Kverkfjoll, so cheesy food it is. Yum.
After many hours of bumpy driving, we reach Kverkfjoll. After being fieldwork nomads for the past few days, it’s nice to finally settle in somewhere for the rest of the trip. Despite its remote location, Sigurdarskali mountain hut is incredibly well-equipped and run by a fantastic bunch of wardens, some of whom will take us up to the summit of Kverkfjoll itself for sampling. This will be our home for the next 10 days.
Now finally at our main destination, it was time for some science! Kverkfjoll has many interesting areas at and around its summit, including the active geothermal areas of Hveratagl and Hveradalur at the top, warm carbonate springs within (another!) deep gorge on its eastern flank (Hveragil), and numerous proglacial fluvial sedimentary deposits, all well-preserved by the cold, dry arctic air. We plan to sample from all these areas during our time here.
The first few days greet us with unstable weather, which limited us to the lower reaches of Kverkfjoll. Hveragil is one of our main targets – a site that has eluded me on previous trips due to its long and difficult road. The national park are keen to preserve this site due to its beautiful carbonate deposits, and as such the road here is not maintained by way of discouraging tourists who like to splash about in the warm spring water that flows through Hveragil gorge. It takes us over 4 hours to cover approximately 40 miles, but it’s worth it and we finally make our way down into another steep canyon to reach the site. The landscape here is spectacular and enormous, and the carbonate-depositing stream seems to come out of no-where. This alkaline stream is a mix of CO2-rich spring fluids emerging from the volcano and glacial meltwater run-off, forming a warm spring that flows along the bottom of Hveragil gorge. The carbonates here produce beautiful patterns, and also provide a home to endolithic microorganisms – bacteria that live inside the rocks to escape the harsh extremes of the cold Icelandic desert.
With the weather still not playing ball, we focus on the sedimentary deposits that dominate the proglacial area of Kverkfjoll. These fluvial sediments are really varied, and provide a nice array of analogue sediments to those on Mars. Sediments that have formed or been deposited by water are of particular interest for Mars exploration, as they are evidence for past habitable systems and are also good at preserving organic matter – the building blocks of life. Sampling these sediments is less adventurous than those at Karahnjukar. A nice easy 3 km stroll later, we have samples, and return home to pizza and beer courtesy of Chef Gunn.
Now with the fieldwork having slipped past the half-way mark, and still no samples from the geothermal areas at Kverkfjoll’s summit, I was starting to get nervous… Fortunately, the weather sensed my fears and finally we had an opportunity to hike up to the top of Kverkfjoll. I last did this hike in 2007, and I vaguely remembered it as a ‘bit of a steep climb’. Maybe its because I’m getting older, or that I have a selective memory, but the hike up to Kverkfjoll is HARD. However, a long slog it may be with all our sampling and SPECI gear, but totally worth it. All four of us go up, led by two of the wardens at the hut. Crampons, harnesses, and ice-axes are donned, and we begin our march upwards, first across Kverkjokull – the heavily crevassed glacial tongue that sidles down Kverkfjoll, and then upwards to the summit along the caldera rim. The ice and craggy peaks make incredible viewing, and finally, we get a precious 2 hours sampling time at Hveratagl.
In the end we made it up to Hveratagl twice – the second trip two days after the first (legs = sore…). Unfortunately we couldn’t get to Hveradalur, where I sampled in 2011. The remote, spectacular nature of Kverkfjoll is both incredible and frustrating in equal measure. We can only sample what the mountain will let us. With all our samples (over 70 in total…going to be busy!) and ourselves packed up and ready to go, it was time to head back to civilisation (aka fresh food, daily hot showers, and a proper bed).
A huge thanks to Charles, Mark, and Matt for such an awesome and successful trip, and for being a fun field team. Also thanks to the wardens at Sigurdarskali hut for all their help getting us up to Hveratagl, especially the second day when the high winds threatened to send us back down, and to Vatnajokull National Park for granting us a research permit. Finally, this fieldtrip is dedicated to the late Prof. Dave Barnes, who sadly passed away just as this trip began. His enthusiasm, encouragement, and big personality made it an absolute privilege to have worked with him, and certainly much of what we did on this trip would not have been possible without him.
This fieldwork was funded by the Royal Society of Edinburgh and the UK Space Agency