Hydrogeological and hydrochemical modelling of density-driven flow in the Tiberias Basin, in particular between Ha'on and Tiberias Regions, Jordan Valley

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In the second phase (the current proposal), all resources will be used to tackle the construction of the 3D model for the highly composite and complex study area, in order to understand the mechanisms of salinization processes below the TB and in particular in the HTR in relation to faults and tectonic features of the basin. Eventually, the current suggested proposal will result in the presentation of the first regional model of density driven flow for the study area. While the 2D and preliminary 3D models already provide insights into the possible transport mechanisms, it is clear that 3D modeling on real structural data will provide a better understanding of the hydrologic processes related to heat and brine migration in faulted basins. Although the 2D models are physically correct, faulted geothermal systems are complex and display huge geological and physical variability. A consequence of this complexity is that several 2D models will not provide a full picture of the system as it is impossible to study the interactions and coupling between the different 2D patterns.As explained in the submitted manuscript (enclosed in the appendix), convective patterns are most likely 3D and need to be addressed in a full 3D model. The preliminary 3D models currently investigated confirmed this aspect (see 3D abstracts).A major goal will be to adapt structural, physical and chemical properties to the 3D requirements of the numerical model. To tackle this problem, (T3) will provide a first regional model of the area allowing (T1) to build preliminary 3D numerical models based on real structural data. The geological model will be permanently refined in a block-wise manner, i.e. major geological/structural boxes will be identified according to natural features of the system (faults, folds, layering etc), hydro-geochemical data (T3 and T2) and updated numerical results (T1). This will require a well-planned co-ordination of the multi-disciplinary approach described above. By now the 2D and preliminary 3D models are completed and show several convective regimes (see enclosed article) and the open question that needs to be addressed are:- How do the 2D patterns develop in 3D?- How can we correctly apply adimensional theory (e.g. Rayleigh, Nusselt) to predict the onset of 3D convection in faults and surrounding units? - Under which conditions convective patterns can still be considered purely 3D or 2D?Solving all these key points will explain:- The driving mechanisms of active flow transport processes in faulted systems- The observed temperatures of brines and their chemical differences within the TB, mainly between the western sources and eastern part of the HTR. - The study of 3D convective patterns and the role of fractures and more permeable zones on deep fluid flow, their influence on the mass and energy migration system.