准噶尔盆地二叠系含油气系统类型及展布

准噶尔盆地二叠系由海陆过渡相、泻湖相和河流相沉积组成，烃源岩发育，具有生、储、盖、圈、保的良好配置条件。中、晚石炭世和二叠纪，准噶尔古陆块受西伯利亚板块、哈萨克斯坦板块、塔里木板块的碰撞，形成了西缘、南缘、东北缘三大前陆盆地系统。由于三个不同地区前陆盆地系统的发育，构成了以二叠系风城组、下乌尔禾组为主要烃源岩的三大盆地级含油气系统。根据对形成盆地内含油气系统的充要条件──静态要素和动态要素的分析，确定出了以三个盆地级含油气系统为单元的七个盆地内含油气系统。各含油气系统都有着各自的形成和分布规律。按其空间展布，又可划为同期并列式、同期交叉式、异期叠合式、异期重合式四种形式。这些形式的有效组合，构成了准噶尔盆地内有利的油气聚集带。

TYPE AND DISTRIBUTION OF PERMIAN PETROLEUM SYSTEM IN JUNGGAR BASIN

Permian in Junggar basin consists of marine-continental transitional facies, lagoon facies, and fluvial facies, possessing widely-distributed source rock and better combination of source rock, reservoir, caprock, trap and preservation conditions. Three large foreland basins formed in western margin, southern and northeastern margin of Junggar basin as Junggar paleo-plate collided with Siberia Plate, Kazakhstan plate and Tarim plate in Middle, Late Carboniferous and Permian, and then be basin-size petroleum systems formed with Fengcheng formation and lower Wuerhe formation of Permian as main source rock. Based on static and dynamic aspect analyses of subordinary petroleum system, seven sub-petroleum systems were determined. According to their spatial distribution, four types of petroleum systems were classified, they are synchronous parallel type, synchronous cross typs, asynchronous overlap type and asynchronous superposition type. Their proper combination formed favourable oil/gas accumulation belt in Junggar basin.