Hot and salty waters occur in the surroundings of the Lake Tiberias. Transient
numerical simulations of thermally-driven flow without salinity effects show
that mixed convection can explain the upsurge of thermal waters through
permeable faults and the high temperature gradient in the Lower Yarmouk Gorge
(LYG). It turns out that by including salinity effects, the flow patterns
differ from those of a purely thermal regime because heavy brines dampen
upward buoyant flow and convective cells. Accordingly, the fault permeability
had to be increased to restore a good fit with the measured temperatures. This
further supports the hypothesis that the high temperature gradient in the LYG
is likely due to fractures or faults in that area. The thermohaline
simulations also suggest that the derivatives of relic seawater brines are the
major source of salinity. Deep brines leaching salt diapirs cannot reach the
surface. However, the presence of local shallower salt bodies below the lake
can potentially contribute to the salinity of the western spring and well
waters, though in very small amount. This is in agreement with geochemical
data according to which the major source of the brines of the Tiberias Basin
represents seawater evaporation brines. Besides being of importance for
understanding the hydrogeological processes that salinize Lake Tiberias, the
presented simulations provide a real-case example illustrating large-scale
fluid patterns due to only one source of buoyancy (heat) and those that are
additionally coupled to salinity
