Saturated hydracarbon of coal,carbonaceous mudstone and oils from the Lower Jurassic coal measures in the Turpan basin were studied,and biomarker characteristics and coal thermal maturity analyzed to draw the following conclusions. There are many similar biomarker characteristics between oil from middl-lower Jurassic of Turpan Basin and coal and carbonaceous mudstone in the same strata. They all contain specific r-lupane, I-norbietane, C24-tetracyclic and high content of C29-steranes. These characteristics suggest that they have similar matter source of the organic matter derived from matter with abundant high plants. Meanwhile, biomarkers often used to indicate depositional environments characterized by high Pr/Ph ratio, little or no gammacerane and high abundance dibenzofurans, such biomarker distributions are indicative of suboxic and freshwater environment. Although coal and carbonaceous mudstone remain in lower thermal maturity (Ro=0.47-0.53), but C29-ββ/(αα+ββ) sterane ratio (0.294-0.489) and bezohopane are detected. Because these ferture are related to bacterial activity, bacterial degrdation of organic matter maybe take an important role in coal-derived oil.
展开▼