摘要:
The Erlian Basin is a group of small Meso-Cenozoic rift basin,which act as an important oil produc-tion zone.During its early stage,structural reservoirs were taken as the main objects.With the deepening of ex-ploration,it is more difficult to find them,and the output of oil production declines rapidly.Therefore,it is ur-gent to search new fields of hydrocarbon exploration for reserve replacement.The hydrocarbon accumulation con-ditions of the Erlian Basin were understood again.It is characterized by small lake basins,multiple sources,rapid deposition and abrupt change of facies belt,which are favorable for the formation of stratigraphic-lithologic reser-voirs.Therefore,a new exploration thought was proposed to change the exploration focus from structural reser-voirs to stratigraphic-lithologic reservoirs.Based on exploration practice,the exploration method for the strati-graphic-lithologic reservoirs was developed:“evaluating resource to determine potential,studying structure to figure out the settings,analyzing sedimentation to search for sandbodies,comprehensive research to build the model,rolling evaluation to determine the scale”.By virtue of this method,hydrocarbon exploration is newly broken through in some sags where new oilfield has not been discovered for over 20 years,such as Bayindulan Sag.Meantime,in A'er Sag newly discovered,A'er oilfield with a hundred million reserves was discovered effi-ciently and quickly by focusing on stratigraphic-lithologic reservoirs according to the successful exploration expe-rience of oil-rich sags.The success of stratigraphic-lithologic reservoirs exploration in the Erlian Basin launches the new hydrocarbon exploration fields in this basin,and can be used as the important reference for the hydrocar-bon exploration in similar basins.%二连盆地为中新生代小型断陷湖盆群,是一个重要的油气生产区,油气勘探早期以构造油藏为主要对象,但随着勘探程度的不断加深,构造油藏发现的难度越来越大,原油产量迅速下降.为了寻找新的油气勘探与储量接替新领域,重新认识了二连盆地的油气成藏条件,认为区内具有湖盆范围小、多物源、快速沉积及相带变化快的地质特点,具备形成地层岩性油藏的有利条件.因此,提出了将勘探重点由构造油藏转变为地层岩性油藏的新思路,并结合勘探实践,探索形成了“资源评价定潜力—构造研究找背景—沉积研究寻砂体—综合研究建模式—滚动评价定规模”的地层岩性油藏的研究与勘探新方法.以新的方法为指导,在勘探多年仍未取得突破的巴音都兰凹陷等含油凹陷实现了油气勘探的新突破;同时,在新发现的阿尔凹陷,借鉴以往富油凹陷勘探的成功经验,注重地层岩性油藏的勘探,高效、快速地发现了亿吨级的阿尔油田.二连盆地地层岩性油藏的成功勘探,不仅开辟了该盆地油气勘探的新领域,而且对类似盆地的油气勘探起到了重要的借鉴作用.