Joely Maak
Report of GLOMAR PhD student Joely Maak about her participation in the Summer School "Field-based research course on hydrothermal systems and the potential impacts of mineral mining" offered by the University of Bergen in Milos, Greece from 14 to 24 October 2023
From the 14th until the 24th of October the leading instructors Dr. Sven Le Moine Bauer, Prof. Steffen Leth Jørgensen, Prof. Bjarte Hannisdal, Prof. Paraskevi Nomikou, Prof. Stephanos Kilias, Eirini Anagnostou, amongst others, guided us through the interesting geology and the importance of hydrothermal vent systems and deposits on Milos (Greece). The overall aim of the course was to identify the impact of deep-sea mining on hydrothermal vent systems. The students were separated into different groups respective to their different focuses during the master's or Ph.D. projects: microbiology, macrobiology, geophysics, and geochemistry. Since my field of study is organic geochemistry, I joined the geochemistry group.
The course started with different field trips, including one to Cape Vani, where we could see the impressive manganese deposits caused by microbial activity and had the chance to follow the fault zone running through Vani into the shallow ocean through snorkelling. Additionally, we visited the Profitis Ilias deposits in SW Milos, which have an economically high percentage of Gold and Silver. Even though we could not see the gold with our own eyes, beautiful quartz crystals and hematite layers formed in cracks within the stone. We also visited the “old sulfur mine” and the fumaroles on top of an active volcano on Milos, where I could also sample material for my Ph.D. project. The high percentage of pure sulfur was impressive!
A personal highlight was the water sampling and CTD measurements from a sailboat for the nexus monARC project, where we could easily see the influence of hydrothermal vent fluids on water geochemistry in the Bays of Paleochori and Spathi and follow the whitish microbial mats with our own eyes. When we were not in the field or on a sailboat, the geochemistry team was snorkeling and sampling in Paleochori Bay for geochemical analyses including pH, dissolved oxygen, conductivity, and nutrients. Further analyses for trace metal contents will follow at the University of Athens by Eirini Anagnostou. For my Ph.D. project, I also sampled sediments and particulate organic carbon to be able to compare samples from the M192 cruise in August, which I took part in, to the very shallow vents of Milos.
While being in the field or the water during the day, we listened to several interesting talks (e.g., from Anette Tvedt from ADEPTH Minerals) in the evenings about hydrothermal systems and the potential impacts of deep-sea mining. On the last day, we held a debate, where every student played the role of various stakeholders in deep-sea mining, which was a delightful but also very interesting experience! Afterwards, all groups presented their results, which completed the summer school.
Overall, I am very thankful that I could participate in the summer school on Milos to connect the offshore geology I saw from the research vessel in August with the on-land geology and shallow-water vents in Milos. It will certainly help me and my Ph.D. project, to have seen hydrothermal vents and the formation of microbial mats in such environments with my own eyes. I want to thank everyone involved in this experience, but especially Sven for leading such an awesome field trip! Furthermore, I would like to express my gratitude to the Deutsche Forschungsgemeinschaft (DFG), which funds my Ph.D. via the Cluster of Excellence EXC 2077 ‘The Ocean Floor – ‘Earth’s Uncharted Interface’.
