Author(s): Anusha L. Dissanayake; Poojitha D. Yapa; Kisaburo Nakata
Keywords: Hydrothermal fluid mixing reactions; hydrothermal minerals; hydrothermal vents; particle distribution; plumes
Abstract: A new numerical model that integrates hydrodynamics, thermodynamics, and the chemistry of mineral formation in deepwater hydrothermal vents is developed. Transport and spread of plume fluid and the minerals formed are simulated in three stages: plume dynamics stage that is momentum and buoyancy driven; transition to far-field conditions as a gravity current; and far-field conditions where the mineral particles move according to advection–diffusion governed by ambient currents and settling velocities that eventually lead to bed deposition. Thermodynamics include the change in plume temperature and its related properties. Chemical reactions due to hot vent fluid mixing with cold entrained ambient water into the plume change its properties and the behaviour. The model considers the formation of several types of minerals. Model simulations and field measurements compare reasonably well for plumes in Atlantic and Pacific Oceans. Results for a simulation in East Pacific Rise 21°N are presented.