Sampling deeply sourced seeps around the icelandic hotspot, Iceland: ISL23 expedition report

The ISL23 expedition, conducted in Iceland during 2023, aimed to investigate microbial diversity and biogeochemical processes in Icelandic geothermal systems. These environments, characterized by extreme physicochemical gradients, provide unique insights into microbial life under extreme conditions. During this expedition we sampled 30 localities in geothermal systems located within neovolcanic zones and older segments of the Icelandic crust, in geothermal systems located within neovolcanic zones and older segments of the Icelandic crust,, including a variety of geothermal features like shallow-sea chimneys, and terrestrial hot springs. We collected fluids, sediments, and gases, alongside environmental data such as temperature, pH, and conductivity, to better understand the interactions between geology, geochemistry, and microbial communities. The samples will contribute to our understanding of microbial life in extreme environments, and offer potential insight into biogeochemical cycling, astrobiology, and biotechnological applications. Ultimately, this expedition aims at expanding our comprehension of how geological activity shapes microbial ecosystems, providing a foundation for future research in Earth’s extreme environments and their potential analogs on other planetary bodies.