HR: 1340h
AN: T23B-1413    [Abstracts]
TI: High-resolution 3D models of mid-ocean ridge hydrothermal systems: The relative importance of axial versus cross-axial flow.
AU: * Coumou, D
EM: coumou@erdw.ethz.ch
AF: Fluids and Mineral Deposit Group, ETH Zurich, Institute of Isotope Geochemistry, ETH Zentrum NW, Zurich, 8092, Switzerland
AU: Driesner, T
EM: driesner@erdw.ethz.ch
AF: Fluids and Mineral Deposit Group, ETH Zurich, Institute of Isotope Geochemistry, ETH Zentrum NW, Zurich, 8092, Switzerland
AU: Heinrich, C A
EM: heinrich@erdw.ethz.ch
AF: Fluids and Mineral Deposit Group, ETH Zurich, Institute of Isotope Geochemistry, ETH Zentrum NW, Zurich, 8092, Switzerland
AU: Geiger, S
EM: Sebastian.Geiger@pet.hw.ac.uk
AF: Institute of Petroleum Engineering, Heriot-Watt University, Edinburgh, EH14 4AS, United Kingdom
AB: We investigated fluid flow patterns at mid-ocean ridge hydrothermal systems in 3D, using a range of permeability patterns. We use high-resolution meshes, containing several million elements, and account for the non- linearities in the properties of pure water at supercritical conditions. These naturally make the simulations extremely cpu intensive. Therefore, we apply recently implemented parallel techniques in CSMP++ and solve the simulations on a large Linux cluster using up to 32 processors. The results show that only for specific permeability distributions, where the permeability is increased towards the ridge axis, spatially separated black smoker fields emerge, as observed in nature. We studied this effect in more detail by solving for a range of permeability models and determining the relative importance of heat and mass transport in the axial plane versus in the cross-axial plane. Our results show that an increased permeability due to faults and fractures in the near axial region play an important role in the formation of hydrothermal convection cells. Further the results show that phenomena like viscous fingering and oscillating vent temperatures, which have been observed previously in 2D models, also occur in 3D.
DE: 0560 Numerical solutions (4255)
DE: 1805 Computational hydrology
DE: 4430 Complex systems
DE: 8416 Mid-oceanic ridge processes (1032, 3614)
DE: 8424 Hydrothermal systems (0450, 1034, 3017, 3616, 4832, 8135)
SC: Tectonophysics [T]
MN: 2007 Fall Meeting