Sedim entary features and evolution of the Dongying Form ation in the tidal area of the L iaohe Basin

doi:10.11743/ogg20100506

Views : 0 下载量: 1025 CSCD: 0

PDF
Export
Share
Collection
Album

Sedim entary features and evolution of the Dongying Form ation in the tidal area of the L iaohe Basin
Vol. 31, Issue 5, Pages: 567-575(2010)
Online First：28 October 2010，

Published：2010
DOI： 10.11743/ogg20100506
稿件说明：

移动端阅览

DOI：

Sedim entary features and evolution of the Dongying Form ation in the tidal area of the L iaohe Basin[J]. 2010, 31(5): 567-575. DOI： 10.11743/ogg20100506.

摘要

综合岩心、钻井、地震等资料，运用现代沉积学的思路和方法，对辽河盆地滩海地区古近系东营组沉积体系特征进行了分析，认为在东营组沉积时期滩海地区共发育扇三角洲、辫状河三角洲、三角洲、湖泊、滩坝以及湖底扇6种沉积类型。沉积体系的时空分布和演化特征受控于构造背景和湖平面变化。东营组三段沉积时期盆地沉降幅度大，为湖盆扩张早期，研究区沉积相以扇三角洲，辫状河三角洲、湖底扇为主;东营组二段沉积时期为湖盆扩张时期，但构造活动减弱，湖盆变浅，研究区沉积相以辫状河三角洲及滨浅湖-滩坝为主;东营组一段沉积时期为湖盆收缩期，除局部深凹为滨浅湖-滩坝沉积外，广泛发育辫状河三角洲沉积。

Abstract

An analysiswas carried out on the sedimentary features of the Paleogene Dongying Formation in the tidal area ofLiaohe Basin based on core，drilling and seism ic data aswell asmodern sedimentology concepts and methods.Six sedimentation types are identified in the Dongying Formation in the tidal area，namely fan delta，braided delta，delta，lake，beach bar and sublacustrine fan.The temporal and spatial distribution as well as the evolutionary features of the sedimentary system in the Formation was controlled by the structural background and lake level variation.The third member of the Formation was deposited in the early stage of lake expansion when the basin was experiencing themost intense subsidence.The sedimentary facies are dom inated by fan delta，braided delta and sublacustrine fan.The second member was formed during the lake expansion when the tectonic movementweakened and the lake basin was shallower.Sedimentary facies during the time were mainly braided delta and shallow lake-beach bar.The firstmemberwas deposited during lake shrinking and braided delta dom inated except for shallow lake-beach bar in local deep sags.