东濮凹陷下第三系沙三段高频层序地层学模式

Junqing High frequency sequence stratigraphy models of Es_ 3 in Palaeogene system in Dongpu depression.

针对东濮凹陷下第三系沙三段砂泥岩薄互层的特点 ,根据其岩性和盐膏岩的分布特征及地震反射结构 ,将沙三段划分为四个三级层序 ,11个四级层序和多个五级层序。由于该区沙三段沉积时期古地形相对平坦 ,高频层序各体系域在平面的分布变化很大 ,低位域可能仅分布在凹陷的中心部位。通过建立的四种高频层序地层模式 ,可以预测低位砂体的分布及岩性圈闭。

According to the characteristics of thin interbeds of sandstone and mudstone, distribution features of its lithology and gypsolith, and seismic reflection configuration of Es 3 in Palaeogene system in Dongpu depression, Es 3 can be divided into 4 3rd order sequences, 11 4th order sequences, and a lot of 5th order sequences. Since the palaeotopography is relatively flat during the sedimentation, the distribution difference among different system domains of high frequency sequence is very large, the lowstand system domain is probably distributed only in the central part of the depression. Distribution and lithologic trap of lowstand sandstones can be predicted by using these four kind of highfrequency sequence stratigraphy models.