The relation between geologic structures and groundwater in Amman Zerqua area (Hashemite Kingdom of Jordan)

Abstract

The rocks outcropping in the Amman-Zerqa area consist of the Kurnub, Ajlun and Belqa Groups of Cretaceous age and the Plateau Group, “Nari” and alluvials of Quaternary age. The main structural feature is the Amman monocline and asymmetrical syncline both having a northeast-southwest direction. The steep flank is on the southeast. The greater number of faults have a direction normal to the axis of the syncline. Due to the lack of data, the aquifer characteristics could not be related to structure for the Kurnub sandstone aquifer. The fracturing on the anticlinal flexures of the AL. formation has increased the secondary permeability of the A4 confined aquifer. Further dissolving action on the fractures has increased the permeability on the northwest flank of the syncline and has created subsurface channelling nearly along the axis of the syncline. The areal extent of the A7 - B2 water table aquifer is limited by the structural features of the underlying A5 - A6 formation. The intense folding of the B2 formation at many locations has caused fracturing and parting of the beds. This has greatly increased the secondary permeability at random locations.