Weak structural belts in this paper refer to Wenan and Lixian slope zones of the oil-rich sags in Jizhong De-pression ,where the exploration maturity is low but resource potentials are large and exploration prospects are good .Based on the integrated analysis of geological elements and in combination with physical simulation experiments ,the paper illus-trates the main controlling factors of hydrocarbon accumulation ,reveals hydrocarbon accumulation patterns and establishes hydrocarbon accumulation models ,so as to provide theoretical guidance for further oil and gas exploration of the weak structural belt .The result shows that the main controlling factors of hydrocarbon accumulation in weak structural belt are source rock ,carrier system and nose structure .Among them ,the source rock controlled the distribution range and the en-richment degree of hydrocarbons ,the carrier system controlled the horizons of hydrocarbon accumulation and the reservoir types,and the nose structure controlled the hydrocarbon migration direction .Two hydrocarbon accumulation models were established for the weak structural belt based on the configuration relationships between the source rock and the carrier system .One is distal stepwise accumulation model on wide-gentle slope zone ,featuring in joint driving of overpressure and buo-yancy,stepwise migration dominated by lateral transportation through sandbody and adjusted vertically by faults ,ac-cumulation in multi-layers far from the source rocks .The other is proximal Z-style accumulation model on gentle slope belt,featuring in driving of buoyancy ,Z-style migration through vertical adjustment of faults and lateral transportation of sandbo-dies,the accumulation in multiple layers near the source rocks .%冀中富油凹陷弱构造带是指文安斜坡带和蠡县斜坡带，其勘探程度较低，但具良好的资源潜力和勘探前景。通过对成藏地质要素的综合分析，结合物理模拟实验，阐明弱构造带油气成藏主控因素，揭示油气成藏规律，建立油气成藏模式，为深入开展弱构造带的油气勘探提供理论指导。研究结果表明，冀中富油凹陷弱构造带的油气成藏主要受烃源岩、输导体系和鼻状构造的控制，烃源岩控制了油气分布的范围和富集程度，输导体系控制了油气分布的层位和油气藏类型，鼻状构造则控制了油气运移的方向。根据烃源岩与输导体系的配置关系，弱构造带主要存在两种油气成藏模式：一种是宽缓斜坡带远源-阶梯状油气成藏模式，油气在超压和浮力的共同驱动下，以砂体的侧向输导为主，配以断层的垂向调节呈阶梯状运移，具有多层系、远距离成藏特征；另一种是平缓斜坡带近源-Z字型油气成藏模式，油气主要在浮力的驱动下，通过断层的垂向调节和砂体的侧向输导呈“Z”字型运移，具有多层系、近距离成藏特征。
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