塔里木盆地巴楚-塔北地区深层寒武系油气成藏过程与勘探方向

塔里木盆地作为典型的海相含油气盆地经历多期构造改造，寒武系地层埋深大，勘探风险高。其中巴楚和塔北作为主要的控藏古隆起，勘探未能取得进一步突破。为此结合钻井、地震和测试分析等基础资料，运用盆地模拟技术，在大区域和广时域上动态恢复油气成藏过程，力求加深认识，指明勘探方向。研究认为：①塔里木盆地下寒武统玉尔吐斯组烃源岩热演化主要有加里东中期、加里东晚期—海西早期、海西晚期和喜马拉雅期晚期4个关键时期，具有坳陷区连续型、斜坡区接力型以及周缘山前带快速型3种热演化模式。②研究区断裂型、输导层型和不整合型输导体系发育，具备油气运移的条件。③通过油气运聚过程研究，提出了反向汇聚型、扩散型和汇聚型3种油气运聚模式。其中巴楚地区东部发育反向汇聚型，西部发育扩散型。塔北地区发育汇聚型。④巴楚东部地区有利的勘探目标为海西晚期前形成并保存较好的构造圈闭，西部地区为现今未被破坏的构造圈闭。塔北地区有利的油气运移指向区位于沙雅隆起西部台地内区域。

Hydrocarbon accumulation process and exploration direction of the deep Cambrian in Bachu-Tabei area,Tarim Basin

Tarim Basin as a typical marine petroliferous basin， has undergone multi-stage structural transformation， with its Cambrian strata deeply buried， highly risky in exploration. No significant exploration breakthrough has been made in Bachu-Tabei area where two major palaeo-uplifts control hydrocarbon accumulation in the region. In this regard， the study focuses on dynamically revealing the hydrocarbon accumulation process in large area and wide time domain by applying basin modeling technology in combination of the basic data of drilling， seismic exploration and test analysis， with a view to deepening understanding and deciphering exploration direction. The research results suggest that： （1） The thermal evolution of hydrocarbon source rocks in the Yuertus Formation mainly underwent 4 key periods， namely the Middle Caledonian， Late Caledonian-Early Hercynian， Late Hercynian and Late Himalayan periods， in 3 patterns of successive evolution in depression area， relaying evolution in slope area and rapid evolution in peripheral piedmont area； （2） Carrier systems of fault type， carrier bed type and unconformity type are well developed in the study area， indicating favorable conditions for hydrocarbon migration； （3） Three hydrocarbon migration and accumulation modes are put forward， that is， reversed confluence mode as shown by east Bachu area， diffusion mode by west Bachu area and confluence mode by Tabei area； （4） The favorable exploration targets in the eastern part of Bachu area are the structural traps formed and well preserved before the Late Hercynian period， and the structural traps well preserved in the western part. The target zone favorable for hydrocarbon migration in Tabei area is situated inside the platform to the west of Shaya Uplift.