استفاده از مطالعات هيدروژئوشيمي براي تشخيص نفوذ آب شور در چاه هاي آب (مطالعه موردي: شهر ساري)

Salt water intrusion in water wells by using of hydrogeochemistry study (case study: Sari City)

This study is carried out in Sari. According to geophysical studies; aquifer of Sari City is like a bowl, which its most thickness is at north eastern part of Sari. The low quantities of electrical resistance under the considered aquifer and indistinguished bed rock are increasing the existence of salt water layer probability. The data sampled in two periods in autumn 2004(1383) and spring 2005(1384) is used to analyze the Hydrogeochemistry of aquifer. By Piper diagram it is proved that there are hydrogeochemistry facies, fresh, blended and salt water. The existence of salt water facies with composition near to sea water, likewise the fast increase of total dissolve solids in the well number 6 and 7 and closing to end of hydrogeochemical cycle in Durov diagram probability groundwater mixing with salt water is increasing. It is based on Series plot; there were increase in the Na and CI concentrations well number 6 and 7 significantly. We used two methods, Composite plots and Revelle for proving saltwater intrusion in studied aquifer. The drawn composite plots of major ions were shown the linear procedure between Na and CI, this mater shows that mixture of saltwater and soft water happens. The most proportion of Ci ions basis of Revelle method on the sum of bicarbonate to carbonate refers to the well number 6 and 7 and the lowest quantity in both cases refers to the Tange Lather (in South of Sari) well number 3 and 4 .This method shows that the mixture of saltwater and soft water happens in the well number 6 and 7.