冲积—河流相层序地层模式探讨及其在济阳坳陷的应用

Discussion on the stratigraphic model in alluvial-fluvial facies sequence and its application in Jiyang depression.

为了更确切的了解冲积-河流相地层格架的时空分布规律,归纳和总结了冲积-河流相层序、准层序组及体系域的划分依据。结合济阳坳陷新近系岩心、地震、测井等资料,对冲积-河流环境层序地层模式进行了探讨。研究认为低水位体系域主要发育冲积扇及辫状河,水进体系域主要发育低弯度曲流河,高水位体系域主要发育高弯度曲流河,水退体系域时期由曲流河向辫状河过渡。济阳坳陷新近系馆陶组和明化镇组下段可划分出七个准层序组:馆陶组分为四个准层序组;明化镇组下段划分为三个准层序组。

In order to know time-space distribution rule of the alluvial -fluvial facies stratigraphic hake, classification basis of sequence,subsequence sets and system tract of the alluvial-fluvial facies was summed up. The stratigraphic model of alluvial-fluvial facies sequence was discussed with the data of core, seismic and logging and so on in Neogene system of Jiyang depression. The author thinks that alluvial fan and braided river develop in lowstand system tract;low-sinuosity meandering river develops in transgressive system tract;high-sinuosity meandering river develops in highstand system tract and transition from meandering river to braided river occurred druring retreat system tract stage. Guantao formation & lower Minghuazhen formation of the Neogene system in Jiyang depression can be classified into four and three subsequence sets respectively.