FEATURES OF MACRO AND MICRO STRUCTURES DETERMINED IN HALITE AND GLAUBERITE DEPOSITS, IN TUZGOLU BASIN (TURKEY)

The study area is located in the southern part of the Tuz Goli in Central Anatolia. Many evaporate minerals e.g. halite, glauberite, gypsum/anhydrite, dolomite and partially calcite, magnesite and bloedite were determined in the Neogene aged evaporitic deposits. Many macro and micro structures were observed in ten cores which of depth range from 655 to 1400 m. Halite mineral is found in three forms in the samples: 1) filling the gaps between the sulfate minerals (matrix), 2) in the massive structure, 3) in the large crystal structure in the mosaic. In the specimens studied, the glauberite mineral is found in two different forms, one being deposited in layers in shallow environments and the other being in the form crystallites with other evaporate minerals in deep. Glauberite crystals are found in macro and microscopic dimensions, especially in the form of banded and random aggregates in the form of spear or partially equilateral quadrangular mosaic and semi-euhedral crystals intercalated with halite and partially anhydrite minerals. Gypsum mineral is found especially in shallow and / or stagnant water as euhedral crystals and can be converted into anhydrite mineral in a very short time due to the change of solution chemistry and diagenesis. Anhydrite minerals usually exhibit banded structures, while single ordered large crystals have also been found.