ABSTRACT: In this study, geological, hydrological, hydrogeological and hydrogeochemical characteristics of Tavas

(Denizli) Plain were investigated in detail. The geological units in the study area were investigated in two groups as

autochthonous and allochthonous and general geological map of the region was prepared. Each lithological unit

is distinguished as permeable, semi-permeable and impermeable units in terms of hydrogeological characteristics

and aquifer potential and a hydrogeological map of the study area has been prepared. In the area, Acıgöl group,

Plio-Quaternary clayey limestone, Plio-Quaternary non-discriminated clastic units, slope debris, Alluvium fan and

Alluvium are porous permeable units; Çameli formation limestone member, Ağaçlı formation, Ortadağ formation,

(Bodrum Nappes, Likya Nappes) are karstic permeable units; Eşme Metamorphics are impermeable units-1;

Marmaris Peridotite (Marmaris Ophiolitic Nappes), Kızılcadağ Melange and olistostrome allochthonous (Marmaris

peridotite Nappes) units are impermeable units-2; and Babadağ formation, Aksu formation, Çamova member and

Gebeciler formation are semi-permeable units. It is determined that the groundwater flow is towards the north-east direction in the plain. In order to determine the hydrogeochemical properties of the groundwater in the study area,

water samples were taken and chemical analyzes were performed. Groundwater in the region are Ca-Mg-HCO3

types. Groundwater is not suitable for human consumption due to limit exceeding As/Mn/Fe/NO3 concentrations.

This is due to the water-rock interactions and/or agricultural activities in the region. It has been determined that

groundwater in the study area can be used as irrigation water.