Definition of Sarab Aquifer Hydrochemical Facies Distribution by Means of Fuzzy C-Mean Clustering and Hierarchical Cluster Analysis Methods

In this research, clustering of a hydrochemical data set from Sarab plain aquifer using Fuzzy C-Means (FCM) and Hierarchical Cluster Analysis (HCA) techniques have carried out and its application in delineation of hydrochemical facies has studied. The statistical clusters are analyzed for spatial coherence and confirming that the clusters have a hydrogeological corresponding to aquifer hydrochemical facies. Groundwater samples using the optimizing the number of the classes and fuzziness exponent using the fuzzy c-mean were grouped into four classes. The data set including 49 water samples and 12 hydrochemical variables form the study area have used. Results from both approach produced cluster centers that can be used in order to identify the physical and chemical processes creating the variations in the hydrochemistry variation of study area. The FCM method is potentially useful in establishing hydrochemical facies distribution. The results showed that the clustering scheme for partitioning water chemistry samples into homogeneous groups produced by FCM method is an important tool for the determination of aquifer hydrochemical facies and the FCM method is more capable to investigate threshold data rather than HCA method that variation is sharp and abruptly.