Basalt Aquifer System (South)

The Azraq-Dhuleil Basin extends over the south-eastern part of the Jebel al Arab basalt field in south-western Syria and north-eastern Jordan, comprising the catchment of the Azraq groundwater discharge area between the Jebel al Arab Mountain range in the north, the northeastern desert in Jordan and the Azraq Plain.

Groundwater in the Basalt Aquifer System of the Azraq-Dhuleil Basin flows from topographically higher parts of the catchment to the major discharge zone in the Azraq area in the south. The groundwater flow regime extends over a combined aquifer system constituted mainly of permeable layers in Neogene-Quaternary basalts and underlying Paleogene chalky limestones. In the Dhuleil area in the west of the Azraq-Dhuleil Basin, the aquifer system also includes Upper Cretaceous limestones and dolomites.

Groundwater discharge appears to be maintained largely by present-day recharge over wide catchment areas with travel periods of more than 20,000 years. Discharge from springs in the Azraq area ceased completely after the creation of a large well field in the area in 1980. Groundwater quality has deteriorated as a result of the infiltration of irrigation return flows in downstream areas where intensive irrigation takes place.