Investigating recharge in the karst spring using hydrogeology and isotope studies (case study: Sangvil anticline)

Physicochemical and isotopic parameters of springs are one of the important parameters in hydrogeological studies, because they represent the primary characteristics of precipitation and the history that groundwater flow in the karst. In order to investigate the flow system in the karst of Jahrom-Asmari formation in the area of Sangvil anticline in Chaharmahal & Bakhtiari provience, discharge, hydrochemical and environmental isotope data of springs, boreholes, precipitation and river were studied and it was determined that the karst flow type of the range is mainly dependent on the joint and fracture and the flow type in the range is diffuse-conduit and diffuse. Since the use of isotope studies in completing hydrogeological studies and detection the type of flow is useful, along with other parameters, Based on the studies carried out in this research, the Meteoric water line in the Sangvil anticline was obtained as the relationship = 6.3 δ18O + 14.8 δD with a correlation of 96%.The average amount of oxygen 18 in meteoric water and water resources is equal to -4.56 and -7.06 permil, respectively, and the average amount of deuterium in meteoric water and water resources is equal to -13.82 and -32.06 permil, respectively. in the present study, the study of environmental isotopes showed that the anticline aquifer has negative values compared to the local meteoric water line, and high volume precipitation and recharge snow determines the isotopic composition of the anticline aquifer. In this way, precipitations with low volume and high isotope composition penetrate less into the aquifer.