Senior Scientist at MARUM
Research Interests:
Fluid geochemistry of deep-sea and shallow-marine hydrothermal vent systems, stabilization of hydrothermally derived metals (e.g. Fe), trace metal geochemistry and trace metal cycling in the ocean, organic and inorganic stabilization of metals in the ocean
Processes controlling the elemental composition of Fe-Mn deposits, selective leaching (bioleaching) of Fe-Mn nodules, ecological effects of deep-sea mining
Research coordination (cruises, proposals, workshops etc.)
Research project: Transport and speciation of hydrothermally derived metals from different island arc systems and mid-ocean ridges
Iron (Fe) and e.g. zinc (Zn) represent limited but essential micronutrients within the marine biogeochemical cycle in most oceans. For many years, hydrothermal vents were neglected as sources of dissolved metals into the oceans.
However, ongoing research has shown that Fe is introduced to the world oceans and stabilized at elevated concentrations by hydrothermal venting, potentially transported thousands of kilometers away from its original source into the distal oceans, thereby contributing to the global oceanic metal budget. This is due to both inorganic (e.g. as sulfide nanoparticles) as well as organic complexation by small metal chelating molecules – so called organic ligands.
Island arc hydrothermalism occurs at much shallower water depths than hydrothermalism at mid-ocean ridges. Hence, dissolved stabilized bioactive trace metals may be transported into the photic zone, the area of highest primary production rates in the ocean. There, hydrothermally derived metals may serve as essential micronutrients (Fe and Zn) or potential toxins (Al or Cu) to marine organisms, such as phytoplankton.
Island arc hydrothermalism has not gained much attention thus far. In our projects related to RV SONNE cruises into the SW Pacific, SO253 (Kermadec Arc) and SO263 (Tonga Arc), we show that the role of this process in the oceans’ biogeochemical cycle of metals and the metals’ bioavailability may have been underestimated to date.
Projects
2026 – 2032 Cluster of Excellence, University of Bremen, MARUM (DFG)
The Ocean Floor – Earth’s Uncharted Interface – Part 2
2019 – 2025 Cluster of Excellence, University of Bremen, MARUM (DFG)
The Ocean Floor – Earth’s Uncharted Interface
Research Unit “REACTOR”, Theme 3: Processes and dynamics of vents and seeps
https://www.marum.de/en/The-Ocean-Floor.html
2018 – 2020 TONGARIFT (BMBF)
active participation as fluid chemistry leader in RV SONNE (SO 263) reserach cruise to the Tonga Island Arc, SW Pacific, June 2018 (Suva-Suva); (Chief scientist K. Haase, Univ. Erlangen; co-PIs: W. Bach, Univ. Bremen, and A. Koschinsky, Jacobs University Bremen); ROV QUEST, CTD, TV grab, rock corer
Blog from the cruise:
https://www.jacobs-university.de/ships-log-sonne-so263
2016 – 2019 HYDROTHERMADEC (BMBF)
active participation in RV SONNE (SO 253) research cruise to the Kermadec Island Arc, SW Pacific, Dec. 2016 – Jan. 2017 (Nouméa-Auckland); (Chief Scientist: A. Koschinsky, Jacobs University Bremen); ROV QUEST, CTD, trace metal free CTD, clean container, in-situ pumps
Blog and video from the cruise:
http://geschichten.ptj.de/so253-en
https://www.bmbf.de/SharedDocs/Videos/de/bmbf/7/73/7393_expedition-sonne.html
2015 – 2017 FLUM (BMBF)
Active participation in RV SONNE (SO 240) research cruise to the Clarion Clipperton Zone, Central Pacific, May 2015 (Manzanillo-Manzanillo); (Chief scientist T. Kuhn, BGR Hannover; co-PIs: A. Koschinsky, Jacobs University Bremen, S. Kasten, AWI Bremerhaven, and H. Villinger, Uni Bremen); CTD, MUC, piston corer, gravity corer, dregde
2013 – 2015 COVOLVE (BMBF)
Active participation in RV SONNE (SO 229) research cruise to the New Hebrides Island Arc, Vanuatu, June 2013 (Townsville-Nouméa); (Chief scientist K. Haase, Univ. Erlangen; co-PIs: U. Schwarz-Schampera, BGR Hannover, and A. Koschinsky, Jacobs University Bremen); ROV KIEL 6000, TV grab, CTD
All projects related to hydrothermal vent fluids are carried out in collaboration with Dr. Dieter Garbe-Schönberg (Univ. Kiel) and his ICP-MS laboratory.
Further previous investigations of shallow hydrothermal vents haven taken place in collaboration with the working group of Dr. Solveig Bühring (Univ. Bremen) at Milos (Mediterranean), Iceland, and Dominica (Caribbean).
Publications:
https://scholar.google.com/citations?user=b6DO6t0AAAAJ&hl=de