Sedimentological-Stratigraphical evaluation of Tertiary carbonates (Soğucak Formation) of Thrace basin (Bozcaada-Kıyıköy)

Abstract

Soğucak formation which crops out in Thrace Basin has characteristics of reefal limestones and is one of the target levels in oil exploration studies in the basin. While this unit directly and unconformably overlies the basement rocks in some areas, it is transitive to siliciclastic-dominated units (Koyunbaba formation) in other areas. The Soğucak formation is comprised of carbonates of the reefal-shore complex which was deposited in ashelf environment as a consequence of a transgression which lasted between Early-Middle Eocene and early Oligocene. The rocks of the lower limit of the age interval of the formation, the Lower Eocene, crops out in Bozcaada only and is transitive to Fıçıtepe formation. In general, the unit was deposited in SE of the basin between middle-Late Eocene, and between Late Eocene and Early Oligocene in NE of the basin. Sedimentological features and age data indicate that Soğucak formation was deposited under the control of antecedent topography and it is the product of a time-transitive transgression together with coastal morphology and sea level changes