苏北盆地是中国东部唯一发现的上白垩统自生自储工业油藏的盆地。通过分析上白垩统泰州组20个油砂和1个原油样品芳烃化合物，发现芳烃馏分以三芳甾烷系列为主，指示母质沉积水体咸化和原油低成熟。来源于高等植物的生物标志物丰度低，反映原油母质以腐泥型为主。芳烃各组分相对含量、三芴系列相对含量和比值、二苯并噻吩/菲等参数反映了原油母质总体形成于强还原的咸水环境，不同地区的还原性存在差异。海安凹陷和高邮凹陷北坡的泰州组原油同属一族群，而吴堡低凸起泰州组原油属于另一族群。利用甲基二苯并噻吩比值换算的镜质组反射率（R_o），推测海安凹陷泰州组原油来源于泰州组未-低熟烃源灶，高邮凹陷北坡的泰州组原油来源于就近泰州组的低熟烃源灶，而吴堡低凸起泰州组原油来源于邻区高邮深凹成熟的阜宁组烃源灶。研究结果对指导油气勘探具有实际意义。

Subei Basin is an only basin in the eastern region of China in which hydrocarbon of the Upper Cretaceous is discovered up to new. The aromatic compounds are determined by Gas Chromatograph-Mass Spectrometer (GC-MS) in 20 oil sands and one oil sample from the Upper Cretaceous Taizhou formation. The series of triaromatic steroid are main aromatic fractions, and indicate the salt water deposition environment of parent materials and low-mature crude oils. The low abundance of biomarkers from higher plant reflects that the crude oils are mainly from the sapropel parent materials. The relative content of aromatic fraction, the relative content and ratios of three fluorene series, and the ratio to dibenzothiophene/phenanthrene suggest that the parent materials of crude oil are formed in the strong reduction environment of salt water. The geochemical characteristics above mentioned are common; however the differences of parameters show that crude oils were from the different source formations. The crude oils of the Taizhou formation could be divided into two groups by the components of aromatic hydrocarbon and the relation of fluorene, dibenzofuran, and dibenzothiophene. The crude of the Taizhou formation at Hai'an Sag and those at the north slope of Gaoyou Sag belong to the one group and come from the Cretaceous Taizhou source formation; however crude oils at Wubao Uplift belonging to another group are from the Paleogene Funing source formation. By using the ratio of vitrinite reflectance (R_o) calculated by methyl dibenzothiophene, it is estimated that the crude oils at Hai'an Sag source come from low-mature hydrocarbon kitchen of the Taizhou formation, and the crude oils at the north slope of Gaoyou Sag source come from the nearest low-mature hydrocarbon kitchen of the Taizhou formation, but the crude oils at the Wubao Uplift source come from the mature hydrocarbon kitchen of the Funing formation at the adjacent deep depressed zone of Gaoyou Sag. The results are of significance for the petroleum exploration at Subei Basin.