Source Rock Potential and Oil to Source Rock Correlation of the Upper Cretaceous (Campanian-Maastrichtian)–Lower Paleocene Units in the Malatya Basin, East Anatolia, Turkey

Abstract

The hydrocarbon potential of possible shale source rocks from the late Cretaceous to early Paleocene (Sarikiz and Kapullu formations) of the Malatya Basin is evaluated using an integration of organic geochemistry. The TOC values for about 67 samples are between 0.03% and 1.32%, and hydrogen indices (HI) are almost below 100 mgHC/gTOC. They contain Type III/IV kerogen and most of the samples are thermally immature. The TOC values of limestone and coaly facies of the unit ranging from 0.28 to 1.28 wt% and 2.18 and 11.89 wt%, respectively; however, they have low S 2 except for the coaly samples. Nevertheless, high maturity samples, where T max averages 543°C that could be resulted from local heat sources. According to the biomarker characteristics of oil seeps from the late Cretaceous carbonates and bituminous from the late Eocene limestones, they have the same origin and however, no oil-to-source rock correlation has been performed in the basin. A negative correlation and no having source rock potential of the Upper Cretaceous shales and biomarker results suggest that seep oils could be originated from the older carbonates source rock than Upper Cretaceous in the basin.