The source rocks are evaluated by using geochemical testing and the hydrocarbon-generating potential is explored in Cretaceous in the Zhangwu fault depression of Songliao Basin. The statistic analysis of organic abundance, type and maturity, and the saturated hydrocarbon chromatography of the Cretaceous source rocks in the Zhangwu fault depression show following three features. (1) The source rocks in Jiufotang Formation is thick, characterized by high organic abundance, good types and low maturity-maturity; (2) The organic matrix of this source rock is from both lower aquatic creatures and higher plants. The Jiufotang Formation was mainly from bathyal lacustrine-lacustrine lower aquatic creatures, and the Shahai Formation was from terrestrial higher plants; (3) The Jiufotang Formation and Shahai Formation source rocks firstly deposited in brackish environment and then, evolved into freshwater environment. In general, they deposited in a reduction environment. The Jiufotang Formation source rock is the main source rock in the Zhangwu fault depression with preferable-good oil potential, and then, the Shahai Formation source rocks.%利用地球化学测试手段,对松辽南部的彰武断陷白星系烃源岩进行了评价,并探讨了其生烃潜力.彰武断陷白垩系烃源岩有机质丰度、类型以及成熟度统计分析与饱和烃色谱共同反映了:(1)九佛堂组烃源岩具有厚度大、有机质丰度高、类型好、成熟度低-成熟的“三高一低”的特征.(2)烃源岩有机质母质来源于低等水生生物与高等植物混生,九佛堂组主要来自半深湖-深湖相低等水生生物,沙海组更多地混入了陆生高等植物.(3)九佛堂组-沙海组烃源岩沉积水介质环境从半咸水-淡水的演变过程,总体处于还原环境.九佛堂组烃源岩是彰武断陷中主力烃源岩,具有较好-好的生油潜力,沙海组烃源岩次之.
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