The first Summer School of the FluxBEATS doctoral network took place in Iceland

The FluxBEATS summer school, held from September 9 to 16, 2025, in the town of Selfoss in southern Iceland was a combination of training and learning about Icelandic geology. Iceland was chosen for its accessible and visible processes related to divergent plate boundaries, which are central to FluxBEATS doctoral projects.

In this newsletter, we are sharing the highlights of the summer school!

“I am always thrilled by the fact that in Iceland you can walk into a plate boundary”, says project coordinator Christoph Beier. “And we even experienced a small earthquake during our first workshop day”, he continues. The earthquake with a magnitude of 3.7 was one of the strongest in the region for a few years.

Photo caption: On-site participants of the FluxBEATS summer school at the Þingvellir, a stunning rift valley located between the North American and Eurasian tectonic plates. Persons standing from left to right are the FluxBEATS doctoral researchers Jakob Rahner (Polito), Francesco Magnani (GTK), Ana Clara Legora Woitech Hecksher (University of Bergen), Yadav Krishna (GEOMAR), Lisa Pirko Heinz (GEOMAR), Jaime Cataldo Bacho (University of Helsinki, UH), Linus Hüne (UH) and Martina Spinella (University of Münster) (back row). Christoph Beier (UH), Elina Lehtonen (UH), Sylvia Sander (GEOMAR), Felix Genske (University of Münster), Joonas Virtasalo (GTK) and Philipp Brandl (GEOMAR) represent the supervisors of the network (front row). Photo credit: Christoph Beier.

Between two plates

In the MSCA FluxBEATS doctoral network each doctoral research project is related to geological and geochemical processes at divergent plate boundaries. Therefore, the location of Iceland between two tectonic plates makes it a geologically unique and perfect location for the summer school. Our program included two full-day field trips.

The first field trip, led by Robert Askew (Natural Science Institute of Iceland, Department of Geology and Geodesy) focused on Icelandic geology, specifically focusing on the Hreppar formation and Eastern Volcanic Zone volcanism.

Photo caption: Robert Askew guiding the FluxBEATS Summer School participants. Mount Hekla, an active volcano, is visible in the background. Photo credit: Elina Lehtonen

The volcanic and clastic rocks of the Hreppar formation were formed during the past 2–3 million years, and the rock record indicates that the rocks were formed in subaerial volcanic eruptions as well as subglacial or subaqueous eruptions (Kristjánsson et al. 1998). Additionally, the Hreppar formation shows a gradual transition in the depositional environment over time, which can be partly linked to climatic cooling (Geirsdóttir 2011).

Photo caption: On the first field day with Robert Askew one of the locations was Háifoss, where you can see a sequence of lavas, tuffs, and sediments from the upper Pliocene. Photo credit: Christoph Beier. 

During the field day we saw excellent examples of pillow basalts as well as other signs of magma-water/ice interactions, such as hyaloclastites, but the lavas also displayed entablature and hackly column features providing information on the cooling history and direction of these lava flows.

Photo caption: Þjórsárdalur lava, erupted ca. 5 200 thousand years ago, shows magma-water interaction in the form of entablature and hackly columns. Photo credit: Elina Lehtonen. 

The second field day, on the Reykjanes peninsula, towards exposures of the most recent eruptions, was guided by Professor Sæmundur Halldórsson and doctoral graduate student Noemi Löw from the University of Iceland.

The plate boundary of the North American and Eurasian plate runs through the southeastern peninsula, and based on the rock record, rifting and volcanic activity take place at intervals of 800–1000 years (Sæmundsson et al. 2020). The first volcanic eruptions on the Reykjanes peninsula for a long time occurred in 2021 in Fagradalsfjall.

Photo caption: Lava flows from the Fagradalsfjall volcano, Reykjanes peninsula. Photo credit: Elina Lehtonen

From hot magma chambers to hot springs 

One integral part of the summer school was to interact with local experts. In addition to the field days, two of our Icelandic colleagues provided us with excellent scientific presentations.

Professor Freysteinn Sigmundsson from the University of Iceland gave an exciting presentation related to crustal formation and the Krafla Magma Testbed (KMT), project targeted at drilling into an active magmatic system.

Photo caption: Freysteinn Sigmundsson giving a lecture on the crustal formation and the Krafla Magma Testbed. Photo credit: Elina Lehtonen.

Freysteinn Sigmundsson introduced us to different ways to study the crustal formation and volcanic activity in Iceland, and participants got a good overview of the causes of the recent volcanic eruptions. The Reykjanes peninsula has experienced an impressive 14 events of diking and 11 eruptions since 2021 (Parks et al., 2023, 2025).

In the FluxBEATS doctoral network several research projects are related to hydrothermal processes at divergent plate margins. A fascinating perspective on this topic was provided in the lecture by Professor Andri Stefánsson from the University of Iceland on the geochemistry of Icelandic hydrothermal systems.

Photo caption: Andri Stefánsson giving a presentation related to hydrothermal systems and their geochemistry. Photo credit: Elina Lehtonen.

With Andri Stefánsson’s presentation we were exposed to the geochemistry of different hydrothermal systems and their associated fluids. Hot springs are also important places for life, and we learned about different organic compounds present in the hydrothermal systems.

And did you know that geological environments contain also superhot hydrothermal fluids with temperatures exceeding 374°C? These occur near magmatic heat sources, such as magma chambers (Stefánsson 2025).

Photo caption: Hot springs in action! During the summer school, we had the opportunity to visit the famous Great Geysir area. Photo credit: Elina Lehtonen.

Training skills that are needed during the PhD life

A key element of the FluxBEATS doctoral network – and of this summer school – was to focus on both scientific and soft-skills training for our doctoral candidates.

During the workshops in Iceland, we covered topics related to PhD life, project planning and management, scientific writing and presenting, supervision and science communication – all led by our research coordinator Elina Lehtonen.

The data management workshop was delivered remotely by Hela Mehrtens and Doris Maicher from the GEOMAR Helmholtz Centre for Ocean Research Kiel. It included a playful yet insightful Lego-based metadata exercise, where participants built a submarine vehicle and recorded the process systematically. This hands-on activity illustrated the importance of clear metadata description and accuracy – and brought out the inner child in all of us!

Photo caption: The Lego-based metadata exercise, in which participants systematically built a submarine vehicle, demonstrated the significance of accurate metadata description. Photo credit: Elina Lehtonen.

Participants of the summer school also practiced geological mapping skills under the guidance of Philipp Brandl (GEOMAR) and Felix Genske (University of Münster). Working in pairs, participants investigated the region’s geological features and later collaborated to compile their results in the larger group.

“The locality ‘Silfurberg’, less than 5 km northwest of Selfoss, offers magnificent insights into volcanic units that are common for the volcanic activity during the last glacial period (>8.6 ka) on Iceland”, summarizes Philipp Brandl. Initially the eruption under water or ice formed pillow lavas before grading into pillow breccias and different generations of glass-rich volcaniclastics. A later dyke cuts through the entire sequence.

Photo caption: View towards the top of the Silfurberg, which means “silver rock” in Icelandic. The silver-grey rocks to both sides of the ridge are zeolite-altered hyaloclastites. They are cut in the middle by a dyke that is more resistant to erosion. The base of Silfurberg is formed by basaltic pillow lava and breccias that erupted in a subglacial environment. The person standing on top of the ridge gives some scale. Photo credit: Elina Lehtonen

One primary goal was to foster connections between doctoral candidates and supervisors, which was achieved successfully. The discussions were helpful for both the doctoral candidates and the supervisors, and we are looking forward to exciting research and the next summer school in Kiel, Germany in 2026!
 
In the next newsletter you’ll get the chance to meet more our new doctoral researchers. In the meantime, make sure to check out the introductions of Linus, Francesco and Jaime, if you haven’t already. Follow us in Facebook and LinkedIn to stay updated! 

This newsletter was written by Elina Lehtonen, Christoph Beier, Philipp Brandl and Felix Genske.

FluxBEATS is funded by the European Union. Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the Horizon Europe Marie Skłodowska-Curie Actions. Neither the European Union nor the granting authority can be held responsible for them.
 
References
Geirsdóttir, Á. 2011. Chapter 16 – Pliocene and Pleistocene Glaciations of Iceland: A Brief Overview of the Glacial History. Developments in Quaternary Sciences, 15, 199–210. https://doi.org/10.1016/B978-0-444-53447-7.00016-7

Kristjánsson, L., Duncan, R.A., and Gudmundsson, Á. 1998. Stratigraphy, palaeomagnetism and age of volcanic in the upper regions of Þjorsardalur valley, central southern Iceland. Boreas, 27, 1–13. https://doi.org/10.1111/j.1502-3885.1998.tb00863.x

Parks, M., Sigmundsson, F., Drouin, V. et al., 2023. Deformation, seismicity, and monitoring response preceding and during the 2022 Fagradalsfjall eruption, Iceland. Bulletin of Volcanology, 85, 60. https://doi.org/10.1007/s00445-023-01671-y

Parks, M., Drouin, V., Sigmundsson, F. et al., 2025. 2023–2024 inflation-deflation cycles at Svartsengi and repeated dike injections and eruptions at the Sundhnúkur crater row, Reykjanes Peninsula, Iceland. Earth and Planetary Science Letters, 658, 119324. https://doi.org/10.1016/j.epsl.2025.119324

Sæmundsson, K., Sigurgeirsson, M.Á., and Friðleifsson, G. 2020. Geology and structure of the Reykjanes volcanic system, Iceland. Journal of Volcanology and Geothermal Research, 391, 106501. https://doi.org/10.1016/j.jvolgeores.2018.11.022

Stefánsson, A. 2025. Superhot Hydrothermal Fluid Reservoirs Identified using Boron and Chlorine Geothermometry. PROCEEDINGS, 50th Workshop on Geothermal Reservoir Engineering Stanford University, Stanford, California, February 10-12, 2025, SGP-TR-229.