Hydrothermal vents and the supply of nutrient metals for the origin and early evolution of life

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The origin, survival, and early evolution of life on the Earth, and if exists, on Enceladus must require transition metals (e.g., Ni, Mo, Cu etc.). Weathering of continental crust followed by riverine transport, which is the main source of metals in the present Earth, was/is limited on the Early earth/present-day Enceladus. Instead, hydrothermal vents (HTVs) and/or weathering of the sub-oceanic rocks are proposed to be the main source of metal on these planetary bodies, however, the metal concentrations in these vents are highly speculative and unconstrained. Furthermore, the existing models that tried to quantify the metal contents in the early ocean on Earth and Enceladus are theoretical and lack the consideration of critical parameters (e.g., organic ligands) that influence metal solubility. The proposed research aims to quantify the metal contents in HTVs and in the ocean on the early earth and Enceladus by performing hydrothermal experiments followed by thermodynamic and mass-balance (Box) modelling. Together these methods would replicate the interaction between early Earth Crust/Enceladus core with corresponding ocean water at various pressures (P) and temperatures (T) and the mixing of HTV fluids with ocean water. Experiments will be performed using novel set-up comprising hydrothermal reactor and syringe pump, which will allow performing multiple experiments in controlled T, P, and redox conditions. The modelling will be done using computer-based software. The proposed research will finally be able to constrain if obtained metal concentrations (in vents and ocean) are sufficient to trigger biologic pathways required for the origin and early evolution of life in these planetary bodies. The results are therefore critical for future space exploration targeting the existence of extra-terrestrial life. With the expertise of the researcher and the host, available facilities at the host institution, the project can be finished within proposed time (24 months).