古地理学报2024，Vol.26Issue(4)：846-862,17.DOI:10.7605/gdlxb.2024.04.032
混合沉积特征精细刻画:以江苏徐州寒武系馒头组为例
Datailed characterization of mixed sedimentation:a case study of the Cambrian Mantou Formation in Xuzhou,Jiangsu Province
摘要
Abstract
The Cambrian Mantou Formation in the Xuzhou area of Jiangsu Province is characterized by mixed siliciclastic-carbonate sedimentation.In this study,a set of typical mixed siliciclastic-carbonate sequences from the Mantou Formation were systematically analyzed for their petrological characteristics based on section and microscopic features.By analyzing the mixed sedimentation characteristics in various sedimentary environments,a mixed siliciclastic-carbonate sedimentation model was established in the epi-continental sea environment.The different types of mixing,mixing processes,and controlling factors of various mixed siliciclastic-carbonate rocks were investigated.Research has shown that there are mainly 11 types of mixed sedimentary combination types in the sequence,including sandy-bearing oolitic limestone,sandy limestone with intraclast,fine-grained limy sandstone,and limy-bearing siltstone.The overall se-quence is a result of frequent fluctuations in secondary sea-level variation,accompanied by multiple peri-ods of storm activity,within the context of epicontinental transgression.It mainly evolves from an inshore mixed carbonate-siliciclastic tidal flat to a mixed restricted platform.The sedimentation in the study area consists of facies mixing and punctuated mixing,with localized occurrences of in situ mixing and source mixing.Climate,terrestrial input,sea level changes,and carbonate yield rate serve as the primary fac-tors influencing facies mixing,with additional influences from biological activities and hydrodynamic con-ditions.The multi-stage storm activity can dominate the formation of punctuated mixing,and promote the development of facies mixing and source mixing to some extent.Under the superimposed influence of vari-ous factors,the study area is characterized by the development of a combination of multiple mixing types.Clarifying the distribution of various mixing types and mixing process can provide reference for the restora-tion of the Cambrian paleoenvironment and sedimentary evolution of the North China Plate.It also offers typical examples for the study of mixed sedimentation in the'deep time'epeiric platform.关键词
混合沉积/陆表海/风暴沉积/沉积模式/馒头组/寒武系/徐州地区Key words
mixed sedimentation/epicontinental sea/storm sedimentation/sedimentary model/Mantou Formation/Cambrian/Xuzhou area分类
天文与地球科学引用本文复制引用
文祖超,沈玉林,李壮福,敬宇鸿,党志英,祝玉琳,孟艳,李林超..混合沉积特征精细刻画:以江苏徐州寒武系馒头组为例[J].古地理学报,2024,26(4):846-862,17.基金项目
地质学江苏省"十四五"重点学科建设项目资助.[Financially supported by the 14th Five-Year Plan Key Discipline Construction Project of Geology of Jiangsu Province] （）
