In this study, organic geochemical characteristics of Upper Pliocene bituminous shale beds in the Akçalar lignite basin, southwest of Konya, Turkey, were investigated using total organic carbon (TOC) and pyrolysis analyses. Additionally, the palaeontological study was carried out to assess the depositional environment of the area. The TOC contents of the studied samples are mostly high, varying between 0.4 and 50 wt%, with an average of 21.35 wt%. The low Hydrogen Index (HI = 17–395 mg HC/g TOC) and S2/S3 ratio (0.15–11.4) values indicate that kerogen of the vast majority of the samples is of Type III and only a few samples contain Type II and IV kerogens. Consequently, most of the organic matter (OM) tends to generate gas, even though a small portion of it exhibits a tendency to generate gas-oil mixture. The studied bituminous rock samples characterized by low Tmax (408–511 °C) and Production Index (PI = 0.08–0.36) values show that the degree of thermal maturity is in the range of immature to early mature. S1, S2 and Potential Yield (PY) values range from 0.04 to 16.16 mg HC/g rock, 0.07 to 115.56 mg HC/g rock and 110 to 131720 ppm, respectively. These values imply, in terms of hydrocarbon generation potential, that the studied samples have a source rock potential from poor to excellent. Additionally, the S1 hydrocarbon type values indicate no external contribution of migrated hydrocarbons to the bituminous rocks of the studied area.
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