Thrace Basin basement, comprises interbedded fine to coarse grained clastics from a variety of depositional environments, turbidite, muddy carbonates with local reef developments, river channels and tuffs. More than 400 wells were drilled till 2008; 14 gas and 3 oil fields were discovered and all of them are producing. Main gas productions zones are between Eocene- Oligocene deposits; Hamitabat (turbiditic sandstones), Ceylan (tuffs), Sogucak (reefal limestone), and Osmancik (deltaic sandstone) formations. Shales of Hamitabat and Mezardere formations have good source potentials. Thrace Basin The European side of Turkey is called the Thrace Basin. It is the largest and thickest Cenozoic sedimentary basin
East Thrace the distribution of ethnoreligious groups in the local "sanjaks" was as follows: The Muslim "millet" was recorded as Turkish, while the church members of the Ecumenical Patriarchate as Greek. In the past century modern East Thrace was the main component of the territory of the Adrianople Vilayet, which excluded the Constantinople Vilayet, but included West Thrace and parts of the Rhodopes and Sakar. A publication from December 21, 1912 in the Belgian magazine "Ons Volk Ontwaakt" (‘Our Nation Awakes’) estimated 1,006,500 inhabitants in the vilayet: East Thrace East Thrace or Eastern Thrace ( or simply "Trakya"; , "Anatoliki Thraki"; ,