Determination of surface deformations in Bolvadin Fault by the precision levelling method and investigation of the relationship with underground water

In this study, the amount of aseismic surface deformation occurring in the centre of the Bolvadin district in the last 10 years was determined by the precision levelling method. Bolvadin district centre has a levelling network consisting of eight profiles perpendicular to the surface deformations, and 12 levelling measurement campaigns were undertaken from 2016 to 2018. From the measurements, it was calculated that over two years, the deformations had reached 100 mm in the study area. Subsequently, the data were collected from the 18th Regional Directorate of the State Hydraulic Works on three water wells in the region showing groundwater levels. It was determined that underground water levels had decreased 5 m in 24 months. Kendall, Spearman and Pearson correlation methods were used to investigate the correlation between groundwater levels and deformations. The results revealed that there was a moderate correlation between surface deformations and decrease in ground water levels except for wells 4 and 5.