GEOCHEMICAL CHARACTERISTICS OF CRUDE OIL AND CORRELATION OF OIL-SOURCE IN MINHE BASIN

Minhe basin is a special type basin with oil,coal and natural gas.The crude oil are characterized by mid-density,lower viscosity,lower sulphur,higher wax,higher content of saturated hydrocarbon,lower C_(27),higher C_(29) sterane.The dark mudstone,oil shale,black mudstone and coal in Yaojie formation of middle Jurassic are the major hydrocarbon source rocks.Xiangtang formation of upper Jurassic and Hekou formation of lower Cretaceous are the major reservoir rocks.The correlation from gas-chromatography of saturated hydrocarbon,sterane,hopane,biomarker of oil-source shows that the crude oil and the dark mudstone, oil-shale in Yaojie formation of middle Jurassic are correlated.The crude oils of Minhe basin are mainly from dark mudstone and oil-shale in Yaojie formation of middle Jurassic.