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
Western Thrace demographics of the region toward increased ethnic homogenization within the territories each respective country ultimately was awarded. This was followed by the large-scale Greek-Turkish population exchanges of 1923 (Treaty of Lausanne), which finalized the reversal of Western and Eastern Thrace region's pre-Balkan War demography. The treaty granted the status of a minority to the Muslims in Western Thrace, in exchange for a similar status for the ethnic Greek minority in Istanbul and the Aegean islands of Imbros and Tenedos. After the German invasion (April 1941), the area was occupied by Bulgarian troops, as part of the triple Axis occupation of