Characterization of marine source rocks by n-alkanes and biomarkers: Interpretation of selected samples

To characterize the marine sources rock of the Çağlayan, Dereköy, Ziyarettepe, Karababa, Karaboğaz, and Dadaş geological formations. Pyrolysis/TOK, GC, and GC-MS analyzes were performed to determine the statistical behavior of the data for n-alkanes and biomarkers. Similarly, a sterane- Cluster analysis was applied to the terpene components. According to the results, the TOK content of the Dereköy Fm. is excellent, the Ziyarettepe, Dadaş, Karababa, and Karaboğaz Formations are good, and the Çağlayan Fm. has a good source rock characteristics. With respect to the type of organic matter, the Dereköy, Karababa and Karaboğaz formations are mainly Type II kerogen, the Çağlayan, Ziyarettepe and Dadaş formations contain Type II-III kerogen. By transitivity, the Karababa, and Karaboğaz formations were deposited in an anoxic environment, the Ziyarettepe and Çağlayan formations were deposited in between a sub-toxic and oxic, while the Dadaş and Dereköy formations were deposited in a sub-oxic. Based on pyrolysis, GC, and biomarkers results, the Dereköy Formation is immature, the Çağlayan and Karaboğaz formations are early maturing, and the Ziyarettepe, Karababa, and Dadaş formations are mature. The data indicate that the Çağlayan, Dadaş, and Ziyarettepe formations are active source rocks and are derived from oil/gas and still have potentiality. The Karababa and Karabogaz formations are active source rocks, produced oil and still have potentiality. Since the Dereköy Formation is immature, it has not yet generated hydrocarbons and, its potential source rocks could generate oil when it reaches the right conditions. As a result of the cluster analysis; the n-alkanes with a medium and high carbon number were clearly separated. The Tricyclic Terpenes were in the same group and are affected by similar factors. Homohopanes were included in two groups as 22S and 22R. Finally, the steranes components were divided into diasteranes and steranes. Key Words: Biomarkers, Gas Chromatography-Mass Spectrometry, Pyrolysis, Rock-Eval 6, Cluster analysis, Marine Formation, Geo-chemistry, Turkey, Geology.