No commercial hydrocarbon is discovered till now in Nanwu sag of the southern depression in the South Yellow Sea basin, and the hydrocarbon resources potential evaluation is poorer by previous research.However, about 200 million tons oil reserves in place were discovered by the end of 2011 in Gaoyou sag of Subei basin, which is nearby the South Yellow Sea basin and both have the similar geological features.To further evaluate the resource potential in Nanwu sag more clearly, the generation kinetics model widely used internationally is adopted to simulate the generation and expulsion history of source rock, in which the parameters of the generation kinetics model are from Rock-Eval analysis of samples of the source rock and the asphaltenes, and are confirmed by the maturity distribution of reserves in place.Results show that the activation energy of the Funing source rock is 209 kJ/mol which is lower than typical lacustrine source rock, and hydrocarbon can be generated in lower maturity.The Funing source rock has the characteristics of early generating and expelling.The oil expulsion amount is up to 2950 million m3, and the resources of oil in place is about 270 million~410 million m3, which is comparable with that of Gaoyou sag.Next step wells should be drilled in the prospects with larger hydrocarbon accumulation area and better trap conditions to get commercial discovery much early.%南黄海盆地南部坳陷南五凹至今无商业油气发现,前人对其油气资源前景的评价也较差,而邻区与其地质背景相似的苏北盆地高邮凹陷截至2011年底已发现探明石油地质储量2亿t.为了进一步阐明南五凹的油气资源潜力,采用目前国际上通用的生烃动力学方法模拟烃源岩的生排烃史.通过烃源岩岩屑和原油沥青质样品的热模拟实验数据计算生烃动力学参数,并以原油储量的成熟度分布数据进行验证.研究结果表明,南五凹阜宁组烃源岩的生烃活化能仅为209 kJ/mol,低于典型湖相烃源岩的生烃活化能,烃源岩在低熟阶段就可以大量生烃,具有早生、早排的特点;南五凹的排烃量可达29.5亿m3,石油地质资源量约为2.7亿~4.1亿m3,资源潜力可与苏北盆地高邮凹陷媲美,下一步应选择汇油面积大、圈闭条件好的构造实施钻探.
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