【摘要】 通过对鄂尔多斯盆地西峰油田三叠系延长组6个油砂样品中游离烃、封闭烃、碳酸盐胶结物烃、束缚烃和石英颗粒包裹体烃的分步分离和抽提,并对每类烃的不同馏分进行GC-MS分析,结果表明,研究区烃类来自同一类型的烃源岩,烃类形成于开阔水体条件下还原的淡水湖相环境,烃类的母质类型来源于 — 型干酪根,主要是细菌和藻类,也有一定量的陆生高等植物的输入。C29甾烷20S/(20S+20R)和ββ/(αα+ββ)的比值,显示从包裹体烃、束缚烃到游离烃,其成熟度逐渐增强,反映了油气从烃源岩进入储层成藏的先后差异。更多还原

【Abstract】 Through the stepwise separation and extraction on free oil, sealed oil, hydrocarbon in carbonate cement, bounded oil and inclusion hydrocarbon within quartz grain in six oil sand samples from Yanchang Fm. （Triassic）, Xifeng oilfield, Ordos basin, all these hydrocarbons have been analyzed by GC-MS. Biomarkers of saturated hydrocarbon fractions in oil sand occurred in different states are analyzed and their geochemical characteristics are studied.The distribution and composition of biomarkers indicate that the parent material types of these hydrocarbons are typeⅠ-Ⅱkerogen deposited in the reducing fresh water lacustrine environment,namely derived mainly from bacteria and algae with small amount of higher plant input. The difference in C₂₉ sterane 20S/（20S+20R） and ββ/（ββ+αα） ratios in these hydrocarbons with different existence state has a increasing tendency from inclusion hydrocarbon, cement oil to free oil,reflecting the different filling steps into the oil pool.更多还原