通过对地震剖面的解释和已发现油气藏特征的研究，结合前人对大西洋形成演化的分析，论述了巴西东北部帕拉-马拉尼郝盆地的构造特征、构造演化和石油地质特征，总结了其油气成藏模式。帕拉-马拉尼郝盆地可以划分为Marajo地块、Para-Maranhao台地、Ilha de Santana台地和Deep Sea次盆等4个二级构造单元。该盆地是典型的被动大陆边缘型盆地，其构造演化经历了裂谷期、过渡期和漂移期3个阶段，形成了不同的沉积充填样式和岩性。Deep Sea次盆内浅水区以早白垩世Caju群页岩和泥灰岩为烃源岩，以晚白垩世Ilha de Santana组裂缝型砂质台地相碳酸盐岩为储层的成藏组合已经得到证实。深水区褶皱冲断带内的逆冲断层相关圈闭发育，古近系Travosas组为周围盆地证实的潜在烃源岩，区内存在深海相Travosas组浊积砂岩储层，是潜在的成藏区域。%Based on the seismic interpretation and reservoir characteristics,combined with previous studies on the formation and evolution of the Atlantic,we analyzed the structural characteristics,tectonic evolution and petroleum geology of Para-Maranhao Basin in northeast Brazil,then summed up its accumulation mode.The Para-Maranhao Basin can be divided into four units,which are Marajo Block,Para-Maranhao platform,Ilha de Santana platform and deep sub-basin.The basin is a typical passive continental margin basin,which experi-enced three tectonic evolutions,i.e.rift stage,transform stage and drift stage,forming different sedimentary styles and lithologies.The accumulation combination is proven that the Albian Caju Group is source rock,which is good for hydrocarbon generation,and the Late Cretaceous Ilha de Santana Group is good reservoir,which is fractured sandy platform carbonate.The traps associated with thrust are well developed in the deepwater fold and thrust belt.The Paleogene Travosas Group is proven to be source rock in the peripheral basin,so it is a poten-tial source rock in this basin.Besides this,the Travosas Group turbidite sandstone is a good reservoir.In sum-mary,this area is thought to have potential for hydrocarbon accumulation.
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