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
Bulgarians in Turkey Orthodox Bulgarians who settled in Ottoman-ruled northwestern Anatolia, possibly in the 18th century, and remained there until 1914. Much more intense was the fate of the Bulgarian population of Eastern Thrace in the Ottoman Province ("vilâyet") of Edirne. According to Lyubomir Miletich's detailed study of the province published in 1918, the Bulgarian population of the province (today mostly in Turkey, with smaller parts in Greece and Bulgaria) in 1912 numbered 298,726, of whom 176,554 Exarchists, 24,970 Patriarchists, 1,700 Eastern Catholics and 95,502 Muslims (Pomaks). In the Çorlu and Constantinople regions, Miletich estimates the Bulgarian population at a further 10,000. After