Supervisors info:
Στέφανος Κίλιας Αναπλ. Καθηγητής Ε.Κ.Π.Α (Επιβλέπων), Αριάδνη Αργυράκη Επίκ. Καθηγήτρια Ε.Κ.Π.Α, Αθανάσιος Γκοντελίτσας, Επίκ.Καθηγητής Ε.Κ.Π.Α
Summary:
Submarine volcanic arcs represent a potentially extensive source of shallow (<2
km water depth) vent fields expelling fluids of potential environmental and
economic significance into the oceans. The observed metal enrichments in Sb and
Tl (Hg, As, Au, Ag, Zn) of hydrothermal solids on the floor of the acidic (pH~
5) crater of the Kolumbo shallow-submarine (<505 m water depth) arc-volcano,
near Santorini, have implications for toxic metal (i.e. Tl, Sb, As, Hg)
transport and biogeochemical cycling in seafloor hydrothermal systems.
The solid phases that fix Sb on the seafloor are proved crucial for reducing
the high hydrothermal flux of this notorious environmental toxin to seawater,
near the fishing area of Santorini that is also one of the most popular tourist
places in the world. The selective partitioning of Sb is most likely the result
of changes in hydrothermal fluid composition, as well as pH and temperature,
which are likely linked to the episodic nature of the Kolumbo hydrothermal vent
system. Alternatively, these variations can evolve from ultra-local fluid
composition variations due to short-lived fluid flow events linked to a seismic
cycle, or they may suggest different chemical microenvironments within chimneys
that may arise from geomicrobiological processes.
Keywords:
Biochemical cycling, Chemical microenvironments, Seafloor hydrothermal systems, Fixation, Toxic metals
