PRELIMINARY ANALYSIS OF GRAVITY DATA FOR THE CRUSTAL STRUCTURE AND PETROLEUM POTENTIAL OF SOUTHEAST TURKEY

Southeast Turkey is structurally complex region (Southeast Anatolian Zone (SAZ)) that is located on the northern margin of the Arabian shelf platform which consists of Pan African lithologies overlain by Cambrian to Miocene sedimentary units. The northern border of the SAZ is the Southeast Anatolian Fold and Thrust Belt which is a continuation of the Zagros fold and thrust belt found in Iran and formed by the compression due to the collision between the Arabian and Eurasian plates. With the SAZ, several deposition cycles formed during rifting and orogenic events have been deciphered including Cambrian-Devonian, Mississippian-Upper Jurassic, Lower Cretaceous-Lower Eocene and Middle Eocene units. A number of these units have produced significant petroleum production in NE Syria and Iran but within Turkey there has been limited production. The majority of the petroleum production in southeast Turkey has been from the mid-Cretaceous Mardin Formation which is karstic limestone formed during the closure of the Tethys Ocean. Even though the petroleum production has been limited to date, the occurrence of significant petroleum reserves in Syria, Iran and Iraq suggests that such reserves may exist in southeast Turkey. In order to investigate the upper crustal structure of southeast Turkey and relate this structure to potential petroleum production, we performed a preliminary analysis of satellite gravity data. This analysis includes the construction of residual gravity anomaly maps created using wavelength filtering and upward continuation, and gravity derivative maps.