Organic geochemical characteristics of miocene bituminous units in the Beypazari basin, Central Anatolia, Turkey

الملخص EN

Middle–Upper Miocene units of the Beypazarı Basin (Central Anatolia - Turkey) are represented by conglomerate, agglomerate, sandstone, siltstone, claystone, coal, bituminous shale, limestone, and tuff.

Extensive outcrops of bituminous horizons just above coal are observed in the region.

Total organic carbon contents of the bituminous horizon vary from 0.37 to 7.07 wt%.

Organic matter is predominantly of algal origin consisting of Type I and Type II kerogens.

Low vitrinite reflection index (Ro = 0.27 - 0.56 %) and Tmax (409 – 437oC) values, together with the Ts/Tm ratio of 1.5, indicate that the organic matter is immature.

Biomarker characteristics verify these results.

According to the Pr/n-C17 and Ph/n-C18, ratios the bituminous units were deposited as organic-rich muds in reducing lacustrine environments.