Investigation of hydrogeological and hydrogeochemical properties of Çarşamba aquifer groundwater

The aim of this study is to investigate the hydrogeological and hydrogeochemical properties of the Çarşamba aquifer. The study area which is located in the western part of the Çarşamba plain, is entirely covered with Quaternary alluvium. According to its hydrogeological properties these alluviums are permeable and can be considered as important groundwater reservoirs. The Stuyfzand hydrogeochemical modeling system was used to determine the hydrogeochemical characteristics of water and the phenomena of cation exchange that occurs between salt water and fresh water. According to this system, it was determined that the water samples are mainly of the F3-CaHCO3+, F2-CaHCO3+ and F3-CaMix+ types. Piper and Chadha diagrams were used to determine the hydrochemical facies of the water samples. Accordingly, it was determined that mostly of water samples are found in the Ca-Mg-HCO3 and Ca-Mg-Cl facies. Gibbs diagram was used for to determine the major mechanisms controlling the groundwater chemistry in the study area. According to this diagram, water samples fall in rock-dominance and the evaporation-crystallization dominance zone. The physical, major ions and pollution parameters of the waters were evaluated according to the Regulation on the Waters for Human Consumption, the Regulation on the Quality Control of Inland Water Resources and the Regulation of World Health Organization. Accordingly, it was determined that the values of Al, Mn, NO2 and NH4 in many wells exceeded the permissible upper limit. The suitability of groundwater for irrigation was evaluated according to %Na, SAR, RSC Kİ, MH, PS, Pİ values, USSL salinity and Wilcox diagrams. According to the results, almost all samples are suitable for irrigation. δ 18O, δ 2H and 3H were carried out to determine the origin, the relative age of the groundwater and if there was seawater intrusion into the aquifer. According to the results, the groundwaters have meteoric origin, have shallow circulation and a short circulation time.