Estimation of Bojnourd aquifer hydraulic parameters using vertical electrical sounding (VES) data

Assessment of aquifer hydraulic parameters (K, T) is very important in groundwater resource management and appropriate decision making. Analysis of pumping test data is the most common and useful method to evaluate aquifer hydraulic parameters. However, this method requires specific condition to do and it is a time consuming process with relatively high costs. Combination of geo electrical data with hydrogeological measurements will decrease the costs somehow. In this study, 66 vertical electrical soundings (VES) withSchlumberger array were performed in Bojnourd plain and 26 of them were selected to determine the aquifer hydraulic parameters. The real resistance and the thickness of subsurface layers were determined by processing the field data using IPI software and with respect to well logs. Using sounding data, which were performed inthe vicinity of pumping test wells, and measured water resistivity data for these wells, the corrected transverse resistance and then transmissivites were calculated, which has acceptable correlation with obtained transmissivites from pumping test analysis(T = 0.503 × R_T^′ − 143.6). In addition, the hydraulic conductivities were determined using formation factor obtained from water quality data (K = 0.02 × F^3.292). Finaly, both iso K and iso-T maps for Bojnourd plain were illustrated using ArcGIS.