Generation of GIS-Based IDW Spatial Prediction Maps for Soil Classes, Atterberg Limits, and Water Content Using Borehole Data: A Case Study of Elazığ City Center

In this study, soil analyses based on the Unified Soil Classification System (USCS), Atterberg limits, water content values, and groundwater level parameters were carried out for a 133.65 m² study area using a geographic information system (GIS). For this purpose, selected borehole data from a total of 210 boreholes located in the city center of Elazığ were used, and GIS-based model prediction maps were generated using the Inverse Distance Weighting (IDW) method. As a result, it was modeled that, within the study area, ML, GM, and CL soil classes are dominant at shallow depths (1.5–4.5 m), GM occurs together with MH at intermediate depths (7.5–9 m), and ML, SM, and GM types become dominant again at deeper levels (15 m). In addition, it was modeled that water content values of 11–20% are dominant across the area, while other ranges (0–10%, 21–30%, and 31–44%) occur at varying proportions at different depths. Overall, the distribution indicates predominantly low to medium water content, and the groundwater potential of the study area is not considered rich. According to the liquid limit, plastic limit, and plasticity index values, two distinct soil zones were identified, as demonstrated by the IDW-based model prediction maps.