The hydrogeological investigation of the alluvium aquifers surrounding the lake Hazar (Elazığ)

In this study, alluvium aqufiers covering a large area especially between the west and southeast of Hazar Lake are researched in detail in terms of hydrogeological and hydrogeochemical features.In this thesis study, alluvion aqufiers around Hazar Lake were researched in detail in terms of hydrogeological features and the hydrogeological characteristics, such as ground water levels, ground water flow directions, permeability, porosity, transmissivity, of these alluvion aqufiers and water quality were determined.The units giving surfacing in the field of study present an array from the old to the young as Upper Jura ? Lower Cretaceous old Guleman Ophiolitic, Senoniyen old Elazığ Magmatites, Maestrihtiyen ? Lower Eocene old Hazar Group, Middle Eocene old Maden Group, Pliyo-Quaternary old alluvions and current alluvions. The precipitation ratio of this area for 22 years, determined by General Directorate of Meteorology, is 601.07 mm and temperature average is 12.3 oC and excess water is %46.73 of the precipitation in this area.The permeability and porosity of disturbed samples taken from the alluvion material in the area of investigation were determined with the methods of permeameter, perforated-bottom box and stemming. According to this, it was calculated that the permeability of alluvion aquifer is between 6.3x10-5 ? 4.42x10-4 m/s, the porosity is between %30-%55 and the conductance is between 1.7x10-5 ? 3.7x10-2 m2/s. Seasonal water levels of the sink shafts and boreholes were measured and water table maps were drawn. General groun water flow direction is towards Hazar Lake and the amount of water flowing into Hazar Lake from the alluvion aquifer in the west of Hazar Lake in the real regime was calculated to be 13245120.In the waters investigated, the major cation is Ca+2, the major anion is HCO3-. The waters were grouped in the first, third and fifth areas according to Piper diagram drawn and the hardness of the waters in this area is more than %50. Ca+2 +Mg+2 > Na+ + K+ and these are carbonated and sulphated waters. Furthermore weak acids are more than strong acids in the water, HCO-3+CO-3 > Cl- + SO4-2?. Therefore, the dominating ions in the waters are Ca+2 , Mg+2 ve HCO-3. To define the convenience of the waters for drinking, chemical components were compared to drinking water standarts and to define the convenience of the waters for using, the waters were investigated with the help of Wilcox and USA Saltiness Laboratory diagrams. It was determined that the water were meteoric-based according to ? 18O - ? 2H diagram drawn based on the results of isotopic analysis. Keywords: Elazığ, Lake Hazar, Hydrogeology, Hydrogeochemistry, Isotopic Hydrology.