Numerical heat and fluid flow simulations of the Atlantis II Deep in the Red Sea were conducted to investigate the development, migration, and discharge of hydrothermal fluids into a submarine depression and determine the conditions necessary to form a brine pool. High-salinity fluids are predicted to form by leaching Miocene evaporates, migrate and convect within young oceanic crust, and discharge onto the seafloor. Predicted fluid discharge temperatures (Tmax, 301 °C), discharge fluid velocities (Vmax, 0.09 m/s), and salinities (Smax, 21 wt%) increase over time and reach values comparable to modern seafloor observations. Established convection patterns and discharge behavior are robust and are not greatly affected by geometry of rock property changes. Modeling results were used to calculate the minimum conditions for hydrothermal fluids from a developing hydrothermal system to mix with seawater, reverse buoyancy, and begin to form a brine pool in a submarine depression. Under conditions encountered on the seafloor (T, 25–300 °C; S, 5–25 wt%), fluid mixtures predicted to pond on the seafloor range from late in the mixing process (99 %) at low temperatures (T, 26 °C) to much earlier (36 % mixing) at higher temperatures (T, 94 °C). A model of brine pool evolution is proposed that describes the processes and conditions necessary to initiate brine pool formation and compares formation conditions with accumulated ore material in the Atlantis II Deep and other locations.
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© 2015, Springer-Verlag Berlin Heidelberg.
Copyright 2016 Elsevier B.V., All rights reserved.
- Atlantis II Deep
- Brine pool
- Buoyancy reversal
- Red Sea