北萨哈林盆地走滑断裂对古阿穆尔河三角洲的控制和影响

摘要

北萨哈林盆地是俄罗斯远东地区重要的含油气盆地,其油气成藏主要与萨哈林—北海道大型走滑断裂和古阿穆尔河三角洲有关.在该盆地油气成藏特征、区域地震解释、精细沉积微相研究基础上,通过对多条横切构造走向的区域大剖面分析,系统探讨了大型走滑断裂与三角洲的共生关系以及二者对盆地油气成藏的影响.研究表明:萨哈林—北海道大型走滑断裂是在印度板块与欧亚板块碰撞的远程效应作用下形成的大型右旋走滑断裂系;同期发育的3期古阿穆尔河三角洲受右旋作用的影响,三角洲沿断裂带由南向北迁移,形成南北两大沉积中心,大型走滑断裂与三角洲联合影响和控制了盆地的油气成藏,盆地东南海域主要勘探领域为以天然气为主的达吉组,盆地东北部海域主要勘探领域为以石油为主的努托沃组、奥克贝凯组.%North Sakhalin Basin is an important petroliferous basin in Russian Far East;its hydrocarbon accumulation is closely related with large-scale Sakhalin-Hokkaido Shear Fault and Paleo-Amur River Delta.Based on the researches on the accumulation characteristics,regional seismic interpretation,fine sedimentary micro-facies,by means of the analyses of many regional sections crosscutting the structural trend or strike,the symbiotic relationship between the large-scale strike-slip fault and the delta and their influences on the hydrocarbon accumulation were discussed.This study shows that large-scale Sakhalin-Hokkaido Shear Fault is a large dextral strike-slip fault caused by the far effect of the collision of Indian Plate and Eurasian Plate;Paleo-Amur River Delta,which was accrued and developed at the same period,was affected by the dextral strike-slip fault movement,divided into three phases,shifted along the fault from south to north,finally developed into two depocenters,the large-scale strike-slip fault and the delta together controlled the accumulation of the oil and gas in North Sakhalin Basin,in the southeastern offshore of the basin,Dagi Formation is the main exploratory field,which is gas prone;while in the northeastem offshore,Nutov and Okobykay Formations are the principal exploratory targets of the oil.