Prof. Dr. Vesselin Mitev Dekov 

Tokyo University of Marine Science and Technology, JAPAN
Okt 2024 - Mär 2025
Fellow

Vesselin Mitev Dekov

Projekte & Publikationen

Abstract

Physico-chemical properties of seawater change dramatically above the critical point (CP): pressure of 298 bars, temperature of 407°C. Nearly all the hot springs discovered on the seafloor until now (>400) discharge hot fluids at temperatures and pressures below the CP. The only seafloor hot spring (Turtle Pits) emitting "supercritical" hot fluids at conditions exactly representing the CP was found in the Atlantic Ocean. Chemistry of the supercritical hydrothermal fluids emitted by this unique hot spring is unusual. The minerals deposited by this fluid are unusual too as they precipitate in contrasting conditions: oxic (iron (Fe)-oxides) and reduced (Fe-sulfides). Our understanding of these processes is very limited and new insight into its chemistry and mineralogy would improve the global picture of hydrothermal sources of metals to the ocean and hydrothermal deposits of valuable metals on the seafloor.

I propose a study of the mineralogy, geochemistry, and isotope (sulfur-strontium - neodymium -lead) composition of the Turtle Pits hydrothermal deposit to decode the redox evolution of the only seafloor hydrothermal system sampled while venting at supercritical conditions and how it contributes to Fe-oxide deposition on the seafloor and dissolved Fe supply to the ocean. Geochemical modeling will give us an idea about the proportion of Fe remaining dissolved in seawater and dispersed in the ocean, and Fe deposited as oxides and sulfides on the seafloor.

Kooperationspartner
Prof. Dr. Wolfgang Bach, Universität Bremen
Prof. Dr. Andrea Koschinsky-Fritsche, Constructor University