Comparison of Interpolation Methods for Groundwater Quality Assessment Based on Hydrogeological Characteristics of Shallow Aquifers (Case Study: Babol-Amol Aquifer)

Groundwater quality management planning is based on spatial distribution of the effective parameter in aquifer pollution. In this study, different interpolation methods in Babol-Amol shallow aquifer were evaluated according to its hydrogeological characteristics. After initial data processing, 21 deterministic and geostatistical interpolation methods with linear and nonlinear relationships including inverse distance weighted (IDW), ordinary kriging (OK), lognormal ordinary kriging (Log_OK), disjunctive kriging (DK), empirical Bayesian kriging (EBK), natural neighbor (NN), trend surface (TS) and Spline were compared in order to select the most suitable interpolation method. The total dissolved solids (TDS) parameter was used in Babol-Amol coastal shallow aquifer near the Caspian Sea in north of Iran. The seven error criteria were used for verification in cross-validation of all sampling wells. The results indicated that the nonlinear Log_OK method produced better results in Babol-Amol aquifer with 71.43 percentage of error criteria. Therefore, it can be concluded that the non-linear Log_OK method had promising performance in shallow aquifers based on their hydrogeologicalcharacteristics.