Evaluation and exploration of groundwater resources by identifying the layer structure using Geoelectrical Method, in Roniz plain West Estahban

Abstract

One of the suitable & affordable methods for detecting karstic zones is geoelectric method. Geoelectric is one of the geophysical field operations, which is designed based on the transmission of electrical current into the ground, creating a potential difference between two points and calculating specific resistance of the ground in different depths. In this method, exploratory studies are carried out based on the standards for the resistance of different soil and rocks, as well as the electrical resistance values of materials such as water, metals, cavities, etc. In this research, in order to identify the karstic zones containing water in the Roniz plain in the west of Estahban, 97 electrical sounding were utilized using Schlumberger array and a maximum flow transmitter length of 300 m. After processing the data, Geological sections were prepared and analyzed. Finally, determined the hydraulic gradient of aquifer from west to east, based on specifying the saturated karsted zone in A2 sounding with a thickness of 140 meters at a depth of 260 meters has an electrical resistance of 100 to 150 ohms and at the place of D2 sounding at a depth of 150 meters with an electrical resistance of less than 100 ohms has 80 M thickness. That means, although the only seasonal river in this plain is near the D2 sounding, and therefore the rate of surface water in this area is at its highest, the maximum thickness of the subsurface aquifer is in the eastern part.

Keywords

• “groundwater resources”
• “vertical electrical sounding”
• “electrical resistivity”
• “geoelectrics”
• “roniz plain”