综合运用露头、岩心、钻测井以及地震资料,在塔里木全盆尺度上,建立了其三级层序地层格架,将塔里木盆地白垩系划分为2个二级层序(SSQ1、SSQ2)和6个三级层序(SQ1～SQ6).通过分析贯穿盆地南北部的地震及连井对比剖面可知,SSQ1、SSQ2的地层厚度存在较大差异,地层在盆地腹部和库车坳陷之间出现了类似“跷跷板式”的升降.指出二级层序的可容空间在库车坳陷与盆地腹部之间具有转换的特点,沙雅隆起充当了可容空间转换带的角色.建立了塔里木盆地白垩系的两种层序地层发育模式,SSQ1整体为粗-细-粗的沉积旋回,主要发育冲积扇、扇三角洲、河流、辫状河三角洲、曲流河三角洲和湖泊等沉积体系;SSQ2为由粗变细的正旋回,总体为一套粗粒的冲积扇-河流相沉积体系.%Through comprehensive analysis of outcrops,cores,well logs,drilling and seismic data,the thirdorder sequence stratigraphic framework of Tarim basin is established on the scale of the whole basin.Two secondorder sequences (SSQ1,SSQ2) and six third-order sequences (SQ1 ～ SQ6) are recognized in the Lower Cretaceous of the northern Tarim basin.The seismic and well correlation profiles across the southern and northern parts of the basin show that the formation thickness difference between SSQ1 and SSQ2 is obvious.The stratigraphy change in Kuqa depression and the abdominal basin is "seesaw-like".Accommodation space transforms between Kuqa depression and the abdominal basin,while Shaya uplift plays a role as the conversion zone in the transformational system.There are two kinds of sequence stratigraphic models of the Lower Cretaceous in the Tarim basin.SSQ1 is a coarse-fine-coarse sedimentary cycle,and the facies are mainly comprised of alluvial fan,fan delta,river,braided river delta,meandering river delta and lake.SSQ2 is a positive cyclic succession within that the grain is fining upward,and is a set of coarse grained alluvial fan and fluvial depositional system.
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