Biomarkers geochemistry of the Alpagut oil shale sequence: an evaluation of dispositional environments and source rock potential from Dodurga-Çorum basin (N-Turkey)

Abstract The Cenozoic Çankırı-Çorum basin, with sedimentary facies of varying thickness and distribution, contains raw matters such as coal deposits, oil shales evaporate. Source rock environment characteristics the shale sequence have been evaluated. studied high organic matter content (from 2.97 to 15.14%) show excellent source characteristics. Oil are represented by very hydrogen index (532–892 mg HC/g TOC) low oxygen (8–44 mgCO 2 /g values. Pyrolysis data indicate that contain predominantly Type I little II kerogen. biomarker reveal presence algal, bacterial terrestrial lipid content. These findings in can generate hydrocarbon, especially oil. High C 26 /C 25 , 24 23 22 21 tricyclic terpane, 31 R/C 30 hopane DBT/P ratios were deposited a lacustrine environment, Pr/Ph ratio is indicative anoxic character for depositional environment. T max values from pyrolysis analysis range 418–443 °C, production ranges 0.01 0.08. On gas chromatography, Pr/nC 17 Ph/nC 18 CPI significantly exceeding 1 determined. Very 22S/(22S + 22R) homohopane, 20S/(20S 20R) sterane, diasterane/sterane Ts/(Ts Tm) calculated data. Results all these analyses Alpagut not yet matured entered generation window.