沉积与特提斯地质2026，Vol.46Issue(2)：420-435,16.DOI:10.19826/j.cnki.1009-3850.2025.10005
鄂西地区震旦系灯影组沉积环境及化石埋藏机制
Sedimentary environment and fossil burial mechanisms of the Sinian Dengying Formation in western Hubei
摘要
Abstract
The Ediacara biota are primarily preserved in siliciclastic rocks globally.However,the Sinian Dengying Formation in western Hubei,China,contains abundant Ediacaran metazoan fossils within carbonate rocks,making their preservation mechanism an interdisciplinary focus across sedimentology,stratigraphy,and paleontology.Based on field outcrop observations,thin-section petrography,and compositional analyses of the Dengying Formation in Zigui,western Hubei,this research identifies nine lithofacies types,reconstructs the depositional environment evolution,and explores taphonomy mechanisms by integrating fossil occurrences and mineral distribution patterns.The Dengying Formation exhibits well-developed storm-induced sedimentary structures,with an upward shallowing trend and a regional southwestward deepening pattern.In the study area,Ediacaran metazoan fossils from the Shibantan Member are typically associated with microbial mats and calcarenites in mid-ramp settings(below the fair-weather wave base but above the storm wave base),indicating that rapid burial by distal storm-derived sands in moderate water depths favored fossil preservation.This preservation model aligns closely with classic Ediacaran fossil occurrences in siliciclastic,volcaniclastic,contourite,and turbidite settings worldwide,highlighting that the in-situ rapid burial of fossils triggered by large-scale clastic flows constitutes a universal taphonomy window for the extensive preservation of the Ediacaran biotas.After the storm deposition,microbial mats rapidly colonized sediment surfaces,forming enclosed anoxic environments where microbial activity induced the precipitation of carbonate,phosphate,and silicate minerals,promoting the mineralization of Ediacaran metazoans.This study systematically reveals,for the first time,the synergistic role of microbial mats,storm deposits,and early diagenesis in fossil preservation within carbonate environments,offering novel insights into biotic-environmental coevolution during the Ediacaran Period.关键词
灯影组石板滩段/埃迪卡拉型化石/碳酸盐岩/风暴沉积/微生物矿化Key words
Shibantan Member/Ediacaran-type metazoan/carbonate/storm deposition/microbial mineralization分类
天文与地球科学引用本文复制引用
肖倩,佘振兵,杨朋,向萌,何钦,郑斐,李月洁,康国秀..鄂西地区震旦系灯影组沉积环境及化石埋藏机制[J].沉积与特提斯地质,2026,46(2):420-435,16.基金项目
国家重点研发计划专项"地球系统与全球变化"(2022YFFO800304) （2022YFFO800304）
湖北省自然科学基金创新发展联合基金项目(2025AFD461) （2025AFD461）
