现代地质2018，Vol.32Issue(2)：364-373,10.DOI:10.19657/j.geoscience.1000-8527.2018.02.15
湖泊细粒沉积特征精细研究:以鄂尔多斯盆地延河剖面长7油层组为例
Detailed Study of Lake Fine Grained Deposition Characteristics: A Case Study from Chang 7 of Yanhe Section, Ordos Basin
摘要
Abstract
Field geological outcrops play a significant role in meticulous depiction of the internal structure of sedimentary deposits and establishing accurate underground geological model.This paper takes Chang 7 of Yanhe outcrop section in Ordos basin for instance,adopts the methods of petrology and field outcrop sedimentology,and detailedly analyses the lithofacies type,characteristies,vertical combination and sedimentary environment of lake fine grained sediments.The results show that Chang 7 of Yanhe outcrop section develops 9 types of lithofacies,including parallel bedding fine sandstone facies,flowing water crossbedding fine sandstone facies,wave forming crossbedding fine sandstone facies,ripple cross lamination siltstone facies,deformation bedding siltstone facies,horizontal bedding(argillaceous)siltstone facies,bulk mudstone facies,horizontal bedding(sandy) mudstone facies,big wavy-straight laminae shale facies.On the basis of combining regional geological characteristics,this paper regards the Chang 7 as distal sources meandering stream deltaic front and shallow-semi-deep lake sedimentary,further divided into 7 categories sedimentary units,among which underwater distributary channel and bar between branches developed well,subsea natural barrier,distal bar and sheet sand developed small scale,shallow-semi deep lake sedimentary only developed at the lower part of the Chang 72 subsegment,mouth bar developed hardly,only partial visible.Thorough research on the vertical distribution characteristics of every sedimentary unit,4 vertical distribution forms of Ⅰ,Ⅱ,Ⅲ,are recognized.Ⅰ 、Ⅱ combination mainly distributed at the research area Chang 71 and Chang 73 subsegments.Ⅲ、combination mainly distributed at the research area Chang 72 subsegments.Section facies analysis shows that during integral Chang 7 deposition period,a fine grained sedimentary sequence of thin to coarse was formed,showing meandering stream deltaic fiont sedimentary-shallow lake-semi-deep lake sedimentary-meanderiing stream deltaic front sedimentary.关键词
细粒沉积/沉积露头/岩相类型/垂相组合/长7段/鄂尔多斯盆地Key words
fine grained sedimentary/sedimentary outcrop/lithofacies type/vertical combination/Chang 7/Ordos basin分类
能源科技引用本文复制引用
吕奇奇,罗顺社,付金华,牛小兵,徐黎明,冯胜斌,李士祥..湖泊细粒沉积特征精细研究:以鄂尔多斯盆地延河剖面长7油层组为例[J].现代地质,2018,32(2):364-373,10.基金项目
国家自然科学基金项目(41672099) （41672099）
国家重点基础研究发展计划“973”项目(2014CB239003) （2014CB239003）
湖北省教育厅科研计划项目(Q20181308) （Q20181308）
长江青年基金项目(2016CQN16). （2016CQN16）
