Delineating groundwater potential zones within the Azraq Basin of Central Jordan using multi-criteria GIS analysis

Abstract

The present study was carried out in the central part of the Azraq Basin of Jordan to delineate the various groundwater potential zones within this region. This study includes eight criteria; land use, soil, slope, rainfall, elevation, lithology, lineament density and drainage density. Data and information regarding these criteria were collated and ascertained through the employment and utilisation of satellite imagery and digital mapping. The weighted linear combination (WLC) technique was then employed to integrate these criteria within the GIS so that the area concerned could be evaluated regarding its various hydrogeomorphic characteristics. A review of the literature was then used to assess each of the criteria. Subsequently the criteria were assigned to various parameters per their significance and rating regarding groundwater potentiality.The delineated groundwater potential map was classified into four distinct zones, namely, low, moderate, high, and very high potential zones. From the study findings it can be seen that approximately17% of the area concerned in this study was shown to have very high groundwater potential, while 2.181% has a low potential and 32.612%is categorised as having high groundwater potential; the largest region was that of moderate groundwater potential, with 48.207% of the land being categorised as such. Furthermore, the groundwater potential zones map was verified against a map of existing wells to calculate the percentage of wells in each potential zone. The results showed that approximately 2% of the existing wells were within low potential zones, 66% were within moderate potential zones, 15% were within high potential zones, and only 17% were within very high potential zones.