CAJ | 학술논문

松辽盆地徐家围子断陷白垩系营城组砂砾岩是深层天然气勘探的主要目标层位.营城组四段可以划分出2个三级层序,即营四下层序和营四上层序.营四下层序沉积期断陷深度大、分布范围小、分割性强,形成了相互独立的火山断陷湖,边界发育多个物源,主要发育冲积扇、扇三角洲以及泛滥平原3种沉积相;营四上层序沉积期为一个统一的大断陷,主物源为北东物源,沉积相的发育具有较强的分带性.利用层序地层学方法建立了等时地层层序格架,认为营四段沉积前的构造格局控制了湖盆不同层序沉积相的展布,徐家围子断陷周缘发育一系列沟谷,并沿轴向凸起东侧相继发育了辫状河-辫状三角洲、扇三角洲以及河流三角洲沉积体系.
송료분지서가위자단함백성계영성조사력암시심층천연기감탐적주요목표층위.영성조사단가이화분출2개삼급층서,즉영사하층서화영사상층서.영사하층서침적기단함심도대、분포범위소、분할성강,형성료상호독립적화산단함호,변계발육다개물원,주요발육충적선、선삼각주이급범람평원3충침적상;영사상층서침적기위일개통일적대단함,주물원위북동물원,침적상적발육구유교강적분대성.이용층서지층학방법건립료등시지층층서격가,인위영사단침적전적구조격국공제료호분불동층서침적상적전포,서가위자단함주연발육일계렬구곡,병연축향철기동측상계발육료변상하-변상삼각주、선삼각주이급하류삼각주침적체계.
The matrix lithology of tight sandstone/gravel reservoirs at the Member 4 of Yingcheng Formation of Xujiaweizi depression in Songliao basin is main target of deep gas prospecting, which includes the upper and the lower of the Member 4 of Yingcheng sequence. During the upper depositional stage, the fault depression is deep and narrow, divided and mutual independent volcanic lake, dominated by the depositional system of alluvial fan facies, fan delta facies (braided delta facies) and flood plain facies; while during the late depositional stage, the fault depression is united and dominated by strongly zonational facies. With the high resolution sequence stratigraphy, the isochronous stratigraphic framework and the depositional evolutional model was built up. The study indicated that structural framework controlled the distribution of various sequence facies in the lake basin.A series of trenches developed in the rim of the fault depression and braided plain, braided delta, fan delta and river delta depositional system developed in the eastern flank to the axial tectonic high.