Investigation of source rock characteristics ofbituminous limestones of upper triassic-lower jurassic Kızılören formation at around Hanönü (South of Akpınar, Konya)

In this study, it was aimed to determine whether the carbonates of Late Triassic -Early Jurassic the Kızılören Formation in the possible oil field including Hanönü (south of Akpınar, Konya) have source rock characteristics. Therefore, by performing rock-eval pyrolysis and palinofacies analyzes on the samples collected from the source rock, the properties and paleoenvironmental features such as the amount of organic matter contained in the samples, the degree of maturation and whether they can produce gas or oil were tried to be determined. The Kızılören Formation, observed in the form of limestones in our study area, offers dark gray, gray colored, thin to medium bedded levels and contains dense calcitic veins and, stylolites. In the Kızılören limestone thin section investigation, 0-28% fossil, 0-25% pellet, 0-7% intraclast, 0-2% ooid, 49-99% micrite, 0-12% sparite were found and mudstone, wackestone and packstone facies were identified in the rock. According to the rock-eval pyrolysis results, the total organic carbon content of the Kızılören Formation samples is very low (<‰5) and it shows weak source rock feature. This is supported by the very low S2 values (<2.5 mg/g) of the Kızılören Formation samples. The low total amount of organic carbon (<‰5) in the part of the Kızılören Formation in our study area indicates that the deposition environment conditions are not very suitable for organic matter accumulation. Therefore, the environment where the Kızılören Formation deposits is shallow marine and rich in oxygen. It was observed that the hydrogen index values in the Kızılören Formation samples were low and medium, and the oxygen index values were medium and high. Therefore, these values emphasize that the limestones of the Kızılören Formation have mixed Type II/III kerogen. It was concluded that the kerogen-forming material was either too little or the protection rate was low in the environment where the Kızılören Formation limestones were deposited. The Tmax values of the Kızılören Formation vary between 337 –451oC in the Hanönü section and 430–449oC in the Küllükgözü section, and our samples fall into the mature phase, which means that most of our samples are in the oil window. The vitrinite values of the Kızılören Formation samples showing mixed hydrocarbon sources fall within the range of maturity (oil window). The production index of the Kızılören Formation is low, while all samples in the Hanönü section fall into the mature area, in the Küllükgözü section, they mostly fall into the mature area. The Kızılören Formation samples are generally medium-well preserved, small amount of palynomorphs and organic matter content of the order of low-medium-abundant. Bisaccate pollen with a wide stratigraphic spread (Paleozoic-Recent) was dominantly observed in all of our samples.