Preliminary investigation of mineralizations of Thenardite associated with sulfate occurrences in Cayirhan - Beypazari, Ankara is presented. Local geology consists of Paleozoic metamorphite schists, Permo-triassic granitic rocks, Middle Jurassic - Upper Cretaceous limestones and marls in flysch facies, Paleocene aged land sedimentaries and marine Eocene units, Miocene to Pliocene aged lacustrine units, which sodium sulfates are associated to. Thenardite, Glauberite and Mirabilite minerals have been detected by XRD analysis. Thenardite formations have precipitated in small lakes during Pliocene in middle Anatolia. Ten thenardite samples have been investigated for Ca, Mg, Sr, K and Na elements in order to determine the geochemical properties of the mineralization. Petrographical and geochemical analyses show varying cycles and phases of mineral paragenesis, indicating sudden changes of evaporate precipitation history.