Thrace Basin Thrace Basin The European side of Turkey is called the Thrace Basin. It is the largest and thickest Cenozoic sedimentary basin in Turkey. The basin is triangular shaped, trends WNW-ESE and was formed by extension in late Middle Eocene to latest Oligocene times. This gas prone basin is located northwest of Istanbul, Turkey. About 9,000 meters of Eocene-Miocene marine clastics and continental sediments were deposited. Several basement faults were reactivated and underwent strike-slip motion in late Miocene times where the famous North Anatolian Fault bounds the southern part of the basin. The Cenozoic sedimentary succession, overlying Paleozoic to Mesozoic metamorphic
Immigration to Turkey enter through the Eastern border, which generally included all Iranians and Afghans who entered illegally. In 1923, more than half a million ethnic Muslims of various nationalities arrived from Greece as part of the population transfer between Greece and Turkey (the population exchange was not based on ethnicity, but by religious affiliation; as Turkey was seen as a Muslim country while Greece was viewed as a Christian country). After 1925, Turkey continued to accept Turkic-speaking Muslims as immigrants and did not discourage the emigration of members of non-Turkic minorities. More than 90% of all immigrants arrived from the Balkan countries.