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随着油气勘探的逐渐深入,近年在川东北地区相继发现了铁山坡、渡口河、普光、龙岗以及元坝等大中型气田后,长兴组—飞仙关组礁滩储层逐渐被重视,成为目前川东北地区主要的勘探层系.因此,本文以长兴组—飞仙关组储层为核心开展川东北地区油气成藏组合特征的研究,并最终预测有利勘探区带.针对以上研究目的,本文从川东北地区长兴期—飞仙关期沉积相入手,结合川东北地区含油气系统以及成藏事件,并通过对典型油气藏特征的剖析,研究川东北地区成藏组合特征.受开江—梁平海槽演化的控制,研究区长兴期—飞仙关期主要发育开阔台地—蒸发台地以及陆棚.长兴组—飞仙关组主要发育有生物礁相孔缝型灰岩储层、台缘(内)滩相孔缝型白云岩储层以及台内滩相孔隙型白云岩储层.以下志留统、中-上二叠统烃源岩为研究核心,研究区主要发育S1-P3ch含油气系统以及P2.P3-P3ch.Ttf含油气系统.通过对川东北地区典型气藏剖析,将长兴组—飞仙关组油气藏划分为S1.P2.P3生-P3ch储短距离垂向运聚模式(元坝模式)以及S1.P2.P3生-P3ch.T1f储垂向运聚模式(龙岗—普光模式).以长兴组—飞仙关组礁滩储层为核心建立3类油气成藏组合,分别为生物礁相灰岩成藏组合、台内滩相白云岩成藏组合以及浅滩相白云岩成藏组合.综合对川东北地区油气成藏条件及其在时空上配置关系的研究,认为南大巴山前冲断带、川东冲断带的达州—开江—梁平—带以及阆中—平昌斜坡带的龙岗地区为长兴组—飞仙关组礁滩储层有利勘探区带;通南巴背斜西南部、九龙山背斜中南部以及中部断褶带为较有利勘探区带.“,”In recent years,with the deepening of oil and gas exploration,the reservoirs of Changxing-Feixianguan Formations reef shoal are gradually valued and become the main exploration layer after the medium-large gas fields such as Tieshanpo,Dukouhe,Puguang,Longgang and Yuanba were found in the northeast of Sichuan Basin.Therefore,this paper studies the characteristics of reservoir -forming assemblages of Changxing-Feixianguan Formations as the core,and finally predicts the favorable exploration plays in the northeast of Sichuan Basin.In view of the research purposes,this paper starts from sedimentary facies in the Changxing-Feixianguan period and combines with petroleum systems and accumulation events,and analyzes the characteristics of typical oil and gas reservoirs,and finally studies characteristics of oil-gas reservoir-forming assemblages in the northeast of Sichuan Basin.Controlled by the evolution of Kaijiang-Liangping trough,study area is mainly open platform-evaporation platform and shelf environment in Changxing-Feixianguan period.The Changxing-Feixianguan Formations develops reef pore-cracks limestone reservoirs,dolomite reservoirs,platform edge (inner) shoal pore-cracks dolomite reservoirs,intraplatform shoal pore dolomite reservoirs.Based on the Lower Silurian source rocks and the Middle-Upper Permian source rocks,the study area is mainly develops S1-P3ch petroleum system and P2.P3-P3ch.T1f petroleum system.Through the analysis of the typical gas reservoirs in the northeast of Sichuan Basin,the Changxing-Feixianguan Formations oil and gas reservoirs are divided into S 1.P2.P3 sourcesP3ch reservoir short distance vertical migration model (Yuanba model) and S1.P2.P3 sources-P3ch.T1freservoirs vertical migration model (Longgang-Puguang model).Based on the reservoirs of Changxing-Feixianguan Formations,three types of reservoir-forming assemblages were established,they are reef limestone reservoir-forming assemblage,intraplatform shoal dolomite reservoir-forming assemblage and the shallows dolomite reservoir-forming assemblage.Based on the study of hydrocarbon accumulation conditions and its relationship in time and space,the South Daba Mountain front thrust belt,the Dazhou-Kaijiang-Liangping area in the thrust belt of eastern Sichuan Basin and the Longgang area in Langzhong-Pingchang slope are favorable exploration plays for Changxing-Feixianguan Formations reef-shoal reservoirs.The southwest of Tongnanba anticline,the middle south of Jiulongshan anticline and the middle broken fold belt are less favorable exploration plays.