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油藏中原油的生物标志化合物不仅可以指示生油岩的类型、成熟度，而且可以反映油藏的充注方向及成藏史．以济阳坳陷中的孤南洼陷和利津洼陷为例，利用生物标志化合物进行油源对比，区分出不同成因的原油，并确定了不同的成藏阶段．孤南洼陷的油田中有分别生成于沙一段和沙三段的原油；利津洼陷的油田中则是来自于沙三段和沙四段的原油．它们各自的成熟度指示成藏的期次和时间．沙一段和沙四段生油岩形成于咸水环境，开始生烃早，对应于Ｒｏ＝０．３５％～０．４０％，Ｃ２９甾烷ｗ（Ｓ）／ｗ（Ｒ＋Ｓ）＝０．１２～０．１５；沙三段生油岩为淡水湖相沉积，开始生烃较晚，对应于Ｒｏ＝０．４５％～０．５０％，Ｃ２９甾烷ｗ（Ｓ）／ｗ（Ｒ＋Ｓ）＝０．３０～０．３５．孤南凹陷两个成藏阶段，分别是渐新世末期及中新世；利津凹陷两个成藏阶段，分别为渐新世早期及末期．在断块盆地中，盆地中心部位的油藏以侧向充注为主，形成单源油藏；在断裂带，特别是边缘断裂带以垂向充注为主，常形成混源油藏．
The biomarkers of the crude oil in the reservoir not only indicate the type and maturity of the source rock, but also reflect the filling direction and reservoir accumulation history of the reservoir. Taking the Lunnan Sag and the Lijin Sag in the Jiyang Depression as an example, the authors used the biomarkers to compare the oil sources, distinguished the crude oil of different origins, and determined different stages of hydrocarbon accumulation. Among the oil fields in Gunnan sub-depression, there are crude oils that are respectively formed in the first and the third member of the Shahejie Formation; in the Lijin sub-sag, the crude oil from the third member and the fourth member of the Shahejie formation. Their respective maturity indicates the period and time of accumulation. The source rock of the first member of Shahejie Formation and Shahejie Formation of Shahejie Formation was formed in a saltwater environment and began to generate hydrocarbon early, corresponding to Ro = 0.35% ~ 0.40%, C29 sterane w / S = 0.12 ~ 0.15; the third member of the Es3 source rocks is a freshwater lacustrine facies, and the hydrocarbon generation started later, corresponding to Ro = 0.45% -0.50%, C29 sterane w (S) / w (R + S) = 0 .30 ~ 0.35. The two reservoiring stages in the Gu Nan Sag are the Late Oligocene and Miocene, respectively. The two reservoiring stages in the Lijin Sag are the Early and the Late Oligocene respectively. In the fault block basin, the reservoirs in the central part of the basin are dominated by lateral charge to form single-source reservoirs. In the fault zones, especially the marginal fault zones, vertical-fill reservoirs are often formed to form mixed source reservoirs.