Hydrogeological and geo-structural assessment of the Dareh-e-Anari spring in the Shirin Bahar karstic area, Khuzestan province

In the study area Chaleh Monar and Shelar anticlines covered by the Asmari formation (160km2), are heavily affected by tectonic processes. As a result a variety of structural features such as fracture, folding and faulting has been developed. The extensive exposure of carbonate rocks and suitable climatic condition (815 mm annual rainfall) created good conditions for karst phenomena in the Shirin Behar area. The structural study indicated that in addition to large scale faults, local faults have been developed. Besides, thefracture’s longitudinal density is more than the lateral density. The aim of this study was to determine hydrogeological characteristics of the Dreh-e-Anari spring with discharge of 2.8 m3/s in Shirin Bahar area. To assess hydrogeological characteristics of the Dreh-e-Anari spring, spring’s hydrograph was analyzed. Analyses of the Darah-e- Anari recession curve showed that the dominant flow regime was conduitdiffuse. The catchment area of the spring was estimated to be about 154 km2.