f An Example of Siliciclastic, Carbonate and Evaporite Transitions: Sivas Eocene Basin, Central Anatolia

Sivas Tertiary Basin is one of the most important basins in Central Anatolia. The closure of the northern branch of Neo-Tethys Ocean during the Early Tertiary is determinant phenomenon in the evolution of this area like other Tertiary basins in the Central Anatolia, such as Çankırı-Çorum, Haymana-Polatlı, Tuz Gölü and Ulukışla Basins. The basin is extended to the northeast-southwest direction, and, narrowed and closed in the east. The Sivas basin is bordered by the Pontide belt in the north, Tauride belt in the south and Kırşehir Massif in the west. The Eocene deposits of Sivas basin show important environmental and lithological diversities reflecting evolution of a basin developed on suture zone. Deposition systems are possessed environmental characteristics that are defined by the assemblages of siliciclastic, carbonate and evaporate facies. Especially within the coastal belt, these transitional environments that are formed by siliciclastic and carbonate assemblages are progressed towards offshore depending on the changing of the sea level. The aim of this study is examination of vertical and horizontal relationships in such different environments, and evolution of the basin during Eocene.