鄂尔多斯盆地延长组坡折带演化及其对砂体的控制作用——以延长组长6油层为例

本文在研究鄂尔多斯盆地构造与沉积背景基础上,通过古水深恢复、地层厚度统计、沉积相组合分析、地震剖面解释等方法,识别出盆地内部有四条沉积坡折带。坡折带的发育受湖盆地形控制。东北部发育三条多级缓坡坡折带,西南发育一条陡坡坡折带,分别控制着研究区三角洲前缘砂体和西南浊积砂体的展布形态。随着沉积中心的迁移和沉积相演化,坡折带和砂体规模在长6不同时期都有所变化。

Evolution and controls of the slope breaks on the Yanchang Formation sandstones in the Ordos Basin: An example from the Chang-6 oil measures of the Yanchang Formation

Four slope breaks including three ramp breaks in the northeastern part and one steep slope break in the southwestern part of the basin have been distinguished on the basis of the integration of tectonic setting,sedimentary background,palaeobathymetry,stratigraphic thickness,sedimentary facies and seismic profiles.These slope breaks have exerted an influence on the distribution of delta-front sandstones and turbidity sandstones.