Eocene Sequence at the Northern Margin of the Sivas Basin: Facies and Depositional Environment

In this study carried out in the Eocene sequence of the northern margin of the Sivas Basin, 11 facies were distinguished. The facies assemblages formed from these facies, where carbonates are dominant and siliciclastics accompany carbonates, reflect different depositional environments reaching from the coast to the deep parts of the sea. These facies assemblage-depositional environments, which are gradually transitional to each other, indicate the existence of a gently sloping ramp type depositional surface. On the land and coast, alluvial fans and fan deltas; in resticted shallow marine environments, porcellaneous foraminiferal packstone-wackestone; in high energy shallow marine environments, hyaline foraminifera-algae containing packstone- boundstone and calcarenites were deposited. Deeper down, in low-energy marine environments below the storm wave base, plankton-bearing mudstone is observed. The main factor controlling this facies and environment diversity is water depth-energy conditions. During periods when the storm was active, these sediments were occasionally reworked and mixed.