Simulation of Submarine Hydrothermal Systems: III. Influence of Geological Structures on Fluid Flow at Mid-Ocean Ridges

Convection at mid-ocean ridges has recently been shown to self-organize into pipe-like upflow zones. These are surrounded by narrow zones of focused, relatively warm downflow. This structure is supported both by observations like magnetic anomalies and high-resolution 3D numerical modeling. The efficiency of the interplay between up- and downflow within this concentric system can be explained purely by the non- linearities of the fluid properties which have been incorporated into the model code of CSMP++ (Complex System Modeling Platform) and therefore represents a first-order effect. In the present study we extent the simulations to evaluate the influence of geological structures on fluid flow at mid-ocean ridges. Previous studies were simulated applying a bell-shaped heat flux at the bottom of a three-dimensional modeling domain of homogenous permeability. By introducing heterogeneity into the permeability structure, we investigate the divergence from the first-order pipe-like system and its effect on heat flux efficiency. These geological features include a basalt-layer overlaying a deeper gabbroic part, a high-permeability axial plane and mid-ocean ridge normal faults. First results of this new set of simulations will be presented.