ORGANIC GEOCHEMICAL CHARACTERIZATION AND MINERALOGIC PROPERTIES OF MENGEN OIL SHALE (LUTETIAN), BOLU-TURKEY

Mengen (Bolu) basin extending northeast-southwest contains Neogene limestone, claystone, marl, lignite, and oil shale sequences. Oil shale deposit has been accumulated in shallow restricted back-platform basins during the Middle Eocene. The Middle Eocene (Lutetian) deposit divides into seven levels [L.sub.1-7]. Level [L.sub.6] consists of oil shale (thickness ranging from few mm to 4 meters), marl, claystone and siltstone intercalations. Investigated oil shale strata of an average 50-cm thickness are green or dark brown in color. Oil shale samples contain mainly quartz, calcite, ankerite, chabazite and smectite minerals. FTIR spectra and exothermic maximum and minimum peaks of DTA and TGA weight-loss curves of oil shale samples are compatible with TOC values and mineral composition, respectively. Total organic carbon (TOC) and genetic potential (GP) values of the oil shale samples are between 1.13 and 28.32 wt.% and 176.11 and 281.22 mg HC/g rock, respectively. Hydrogen index (HI) and [T.sub.max] values range from 497 to 968 mg HC/g rock and 430 to 442°C, respectively. TOC and GP values indicate a good source rock potential of this oil shale, and [T.sub.max] values show its general immaturity. The samples stand mainly between types I and II of the evaluation path but closer to type I. This type of organic matter can generate oil upon pyrolysis.