Groundwater hydrology and paleohydrology of the Dead Sea rift valley

The Dead Sea rift valley serves as a deep base level, to which surface waters and groundwaters drain. Two lakes are currently located within the rift: the fresh-water Sea of Galilee (210 m below mean sea level [bmsl]) and the hyper-saline Dead Sea (415 m bmsl). Fresh groundwaters and hot brines flow toward these lakes through carbonate, basaltic, sandstone, and alluvium aquifers. The Dead Sea rift is a unique global site for studying the coupled relationships between Basin evolution and groundwater flow. The temporal and spatial distributions of elevations and salinities of groundwaters and lakes are strongly related to past conditions of tectonics, sedimentation, and erosion. Moreover, climate variations have induced changes in the rift's water mass balance, triggering lake level fl uctuations and temporal and spatial changes in lake salinity. These effects were analyzed using Basin-scale transient hydrogeological numerical models that solve the coupled variable-density groundwater flow and transport of heat and solutes. Furthermore, several ambiguous hydrological phenomena are currently observed at the Dead Sea rift: the existence of fresh and saline springs near each other as well as hot and cold ones; direct and opposite relationships between springs' dischargesalinity-temperature; different geochemical compositions of waters and brines; and complicated spatial distribution of groundwater heads. These phenomena are also explained and analyzed using various hydrogeological numerical models. In addition, quantitative examples of groundwater flow regimes in a few aquifers at the rift vicinity are provided.