Simulation of hydrothermal vents in the Izena Cauldron, Mid Okinawa trough, Japan and other Pacific locations

• Modeling of hydrothermal vent fluid and mineral particle transport and distribution in the ocean.
• Modeling of formation reactions of mineral particles.
• Bathymetry of the ocean bottom is taken into account for particle deposition on the ocean bottom.
• Model application to vent plumes in the Okinawa trough and Main Endeavour Ridge in the Pacific Ocean.

Simulation results of Jade hydrothermal vent in Okinawa trough, Japan and Dante hydrothermal vent in Endeavour ridge in the north east Pacific are presented using an improved version of MOHTV model. The results are presented along with some limited field comparisons. A limited study on the sensitivity of model results to key model parameters is also presented. The model used is capable of simulating the hydrodynamics, thermodynamics, and mineral formations in underwater hydrothermal vents. The transport and spread of the plume fluid and 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 the ambient currents and mineral particle settling velocities that eventually lead to their bed deposition. Thermodynamics include the changes in plume temperature and its related properties such as the vent fluid density. Physico-chemical processes are the chemical reactions that occur in the plume due to the hot vent fluid mixing with cold ambient water. Chemical reactions form new compounds (mostly minerals), which change the plume properties and therefore its behavior. Model simulates the formation of minerals namely FeS, FeS2, ZnS, CuFeS2, CuS, PbS, CaSO4, BaSO4, and Particulate Manganese – PMn. This improved version of MOHTV considers a user defined particles size distribution, the bathymetry of the ocean bottom, and can be used to run long-term simulations. The model results compare reasonably well with the field data. The parametric analyses show, which input and/or ambient conditions most affect the distribution of particles.