近岸水下扇沉积体系高精度层序地层学研究

以东营凹陷胜北断层下降盘坨85块沙河街组沙三中亚段近岸水下扇沉积体为例,对近岸水下扇沉积体系下的高精度层序地层学进行了研究。经过分析认为,近岸水下扇沉积体系中的高精度层序地层单元划分为准层序组、准层序、层组、层四级,并对准层序和层组的类型和对比方法进行了总结。将近岸水下扇积体系中的层组类型划分为Fu(Fineup)、Cu(Coareseup)和Hu(Homogenicup)三大类,准层序类型划分为Cu-Fu、Cu-Cu、Cu-Hu三大类,同时总结出了沿物源方向的相序递变和垂直物源方向的侵蚀切割对比2种准层序对比模式和侵蚀叠置、相变对比、薄砂层对比、相似渐变等4种层组对比模式。

High-Resolution Sequence Research on Nearshore Subaqueous Fan System

This paper discusses the high-resolution sequence in nearshore subaqueous fans sedimentary system, exemplifying T85 nearshore subaqueous fans of the third middle member of Shhejie Formation in Shengbei fault's downthrown side of Dongying depression. The research shows that the high-resolution sequence stratigraphic units are divided into parasequence set, parasequence, bed set and bed in the fan-delta.Types and comparison methods of parasequence and bed set are especially studied. The type of bed set is divided into Fu, Cu and Hu, and parasequence into Cu-Fu, Cu-Fu and Cu-Hu. Two comparison methods of parasequence are provided that are facies change paralleling to source area and incision perpendicular to source area and four models of bed set which are correlation of overstacking, correlation of facies change, correlation of thin sandstone bed and correlation of similar changing of lithology.