Thermal Maturation and Source Rock Potential of Sedimentary Succession in Southeast Anatolia, Turkey

Abstract

There are numerous oil fields in southeast Anatolia, near the northern extension of the Arabian Plate. Ihe formations range from Cambrian to Miocene. Maturation and source rock potential of these formations are determined using reflectance and geochemistry. Tectonic features of these for ma no^ and oil reserves in the region are elaborated and oil generation is interpreted using these data. The maturity of rock units generally increases from west to east, while physical and chemical properties of oils also change accordingly. Oil reserves are generally located in east-west trending anticline systems in Cretaceous reservoirs. Ihe APl gravities and the alkane content of oils increase toward the east, while asphaltene content decreases in the same direction. All geological and geochemical data leads us to interpret that the oil is most probably generated near the west border of districts IX and X and migrated to the east.

Role of Maturity in Controlling the Composition of Solid Bitumens in Veins and Vugs from SE Turkey as Revealed by Conventional and Advanced Geochemical Tools

“…As shown by the T max contour map (Figure d), there is a clear maturity trend which increases from west to east across the region in the direction of the tectonically active zone. The same maturity trend has also been reported for indigenous organic matter in different sedimentary units . It should be noted that T max at very high maturity levels displays increased scatter due to the flat profile of the S2 peak, but the overall T max profile remains as shown.…”

“…The same maturity trend has also been reported for indigenous organic matter in different sedimentary units. 51 It should be noted that T max at very high maturity levels displays increased scatter due to the flat profile of the S2 peak, but the overall T max profile remains as shown. Oxygen Index (OI) values are generally low (0−10 mg CO 2 /g TOC); higher values (21−76 mg CO 2 /g TOC) measured on four samples in the east might reflect enhanced levels of weathering.…”

Tectonic Evolution of Northeast Syria: Regional Implications and Hydrocarbon Prospects

“…The work of Serryea (1990) suggests that the Silurian and Ordovician age sources in northeast Syria are generally mature. In southeast Turkey, where Silurian oil and gas discoveries have been made, the Silurian Dadas Formation is the best source with total organic carbon content of 2-5% and favorable maturity (Harput et al, 1992), similar to results from the Tanf Formation in north Syria.…”

“…The relatively minor Late Mesozoic extension and Late Cenozoic horizontal shortening described in this paper were critical to the plays in northeast Syria, southeast Turkey, and northwest Iraq (e.g. Harput et al, 1992). Hydrocarbons are trapped in fault blocks and fault-propagation folds above reactivated normal faults.…”