摘要
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。
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 frame- work and the depositional evolutional model was built up. The study indicated that structural framework eontrolled the distribution of various sequenee 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.
出处
《吉林大学学报（地球科学版）》
EI
CAS
CSCD
北大核心
2009年第6期983-990,共8页
Journal of Jilin University：Earth Science Edition
基金
国家重点基础研究发展计划项目(2009CB219308)
关键词
徐家围子断陷
白垩系
营城组
层序地层
沉积相
松辽盆地
油气
Xujiaweizi depression
Cretaceous
Yingcheng Formation
sequence stratigraphy
sedimentary facies
Songliao basin
petroleum gas
