古地理学报2025，Vol.27Issue(4)：840-852,13.DOI:10.7605/gdlxb.2025.021
中条山陶家窑剖面长城系混合沉积特征与发育模式
Characteristics and development patterns of mixed sedimentation of the Changchengian in Taojiayao outcrop of Zhongtiao Mountains
摘要
Abstract
A set of marine strata dominated by clastic rocks was deposited during the Changchengian period in the Zhongtiao Mountain region of Yongji,Shanxi.These strata are the earliest sedimentary strata in the Ordos region,recording a complete history of the rifting activities during the Changchengian period.The strata contain four lithostratigraphic units including,from bottom to top,the Baicaoping,Beidajian,Cuizhuang,and Luoyukou Formations.Among them,the Baicaoping and Beidajian Formations are domi-nated by quartzose sandstones,the Cuizhuang Formation by shale,and the Luoyukou Formation by dolo-mite.In this study,various mixed sedimentary deposits were discovered in the Taojiayao section of the Zhongtiao Mountains.This study combines field sedimentary structures with microscopic observations to clarify the characteristics and types of mixed sedimentary deposits and further reveals their origins and pat-terns.The result shows that the Baicaoping Formation is a mixed-facies deposit with massive structures;the Beidajian Formation contains in-place mixing,phase mixing,and intermittent mixing deposits,pre-sented as medium-to-thin layers interspersed in cross-bedded quartzose sandstone;the Cuizhuang Forma-tion develops a small amount of mixed-facies deposition;the Luoyukou Formation mainly contains source-mixed deposits.The mixed sedimentary processes were controlled by rifting:in the early stage with intense rifting,the steep slope landform was dominated by mixed facies;during the Beidajian period with weakened rifting,a gentle slope formed,leading to the development of mixed-facies,and in-place and intermittent mixing deposits;during the Luoyukou depositional period when rifting ended and sea-level dropped significantly,the carbonate rocks deposited earlier were exposed and eroded,and transported into the basin interior as internal debris forming source-mixed deposits.Overall,mixed deposits appeared at the top of each formation during the period when the sea-level began to accelerate,suggesting that sea-level rise was a fundamental condition for determining mixed deposition to a certain extent.关键词
混合沉积/混积类型/沉积模式/长城系/中条山/山西省Key words
mixed sedimentation/types of mixed sedimentary deposits/patterns of mixed sedimen-tary deposits/Changchengian/Zhongtiao Mountain/Shanxi Province分类
天文与地球科学引用本文复制引用
陈亮,任军峰,李涵,潘星,季汉成,陈发清..中条山陶家窑剖面长城系混合沉积特征与发育模式[J].古地理学报,2025,27(4):840-852,13.基金项目
中国石油大学(北京)科研基金(编号:2462023BJR011)、中石油科技创新基金(编号:2021D002-0102)和中国石油长庆油田分公司科研项目(编号:2023DJ0104,2023YQX10105)联合资助.[Co-funded by Science Foundation of China University of Petroleum,Beijing(No.2462023BJR011),CNPC Innovation Fund(No.2021D002-0102),Research Project of PetroChina Changqing Oilfield Company(Nos.2023DJ0104,2023YQX10105)] （北京）
