【摘要】 应用层序地层学理论,综合利用岩芯、测井、地震等资料,建立了梨树断陷七棵树地区下白垩统沙河子组与营城组层序地层格架,并探讨了其与沉积、构造演化的对应关系。结果表明:七棵树地区沙河子组与营城组可以识别出4个三级层序界面和3个最大湖泛面,划分出3个三级层序(SQ1、SQ2、SQ3),每个三级层序又划分为湖侵(TST)和高位(HST)两个沉积体系域;识别出3种沉积相类型:扇三角洲相、辫状河三角洲相和湖泊相。在层序地层格架内,利用钻、测井资料和地震资料对沉积体进行分析,并以此为依据,进一步研究了体系域内沉积相平面展布特征及演化规律,结合现今构造形态,认为有利的油气勘探区主要是东南三角洲体系前缘砂体上倾尖灭形成的岩性—断层复合圈闭,纵向上以SQ1和SQ2层序高位体系域砂体为最优。更多还原

【Abstract】 Based on logging and seismic data,the sequence stratigraphy of the Lower Cretaceous Shahezi and Yingcheng formations in the Qikeshu area,Lishu rift,was analyzed.The results show that four 3rd order sequence boundaries and three 3rd order sequences can be identified.Each sequence can be divided into two system tracts(TST and HST).Three kinds of sedimentary facies are identified,including fan delta, braided delta and lacustrine facies.Within the sequence stratigraphic framework,the depositional bodies are characterized using drill core,logging,and seismic data.Furthermore,the distribution and evolution of sedimentary facies in the system tracts have been analyzed.The results indicate that the favorable exploration areas are lithology-fault combination traps which were formed in the southeastern delta front sand bodies by updip pinchout.The highstand system tract sandbodies of SQ1and SQ2are the best exploration targets.更多还原