摘要
贵州克脚剖面二叠系-三叠系界线附近地层连续,露头良好,长兴期菊石动物群化石丰富。根据该剖面大隆组-大冶组底部菊石化石的分布,自下而上划分出3个菊石带:Huananoceras-Tapashanites带(第22～32层)、Pseudotirolites-Pleuronodoceras带(第33～70层)、Hypophiceras-Ophiceras带(第72～74层)。对该剖面菊石带划分及区域对比表明,Huananoceras-Tapashanites带的时代为长兴期早期,Pseudotirolites-Pleuronodoceras带为长兴期晚期,Hypophiceras-Ophiceras带为长兴期末期-印度期早期。另外,对华南二叠系-三叠系界线地层序列的区域对比,以及克脚剖面菊石标准化石的分布表明,克脚剖面第71层的灰白色黏土岩和顶部的黑色泥岩,分别相当于煤山剖面第25层和第26层;第72～74层的泥质灰岩,相当于煤山剖面第27层;第75层的灰白色黏土岩,相当于煤山剖面第28层。同时,剖面第73层产菊石Ophiceras sp.,是三叠纪的标准化石,因此,本剖面二叠系-三叠系界线位于第72层内部(第72层共厚20cm)。
Abundant ammonoid fossils were found in the Permian-Triassic boundary (PTB)strata from the Kejiao Section,Huishui County,southern Guizhou Province.According to the distribution of ammonoid species from the Upper Permian Dalong Formation to the base of the Lower Triassic Daye Formation, three ammonoid zones are recognized:Huananoceras-Tapashanites zone (beds 22to 32),Pseudotirolites- Pleuronodoceras zone (beds 33to 70)and Hypophiceras-Ophiceras zone (beds 72to 74).The Huananoceras-Tapashanites zone at Kejiao section is equal to Tapashanites-Shevyrevites zone in South China,typical for the early Changsingian.The Pseudotirolites-Pleuronodoceras zone at Kejiao section is equal to Pseudotirolites-Rotodiscoceras zone,typical for late Changsingian.The Hypophiceras-Ophiceras zone at Kejiao section is typical for the end Changhsingian to the early Induan.According to the correlation of Permian-Triassic boundary strata among sections in South China and the ammonoid distribution in Kejiao section,gray claystone and black mudstone in bed 71 is respectively equivalent to bed 25 and bed 26in Meishan section,beds 72-74(argillaceous limestone)is equivalent to bed 27in Meishan section and bed 75 (gray claystone)is equivalent to bed 28 in Meishan section.In addition,ammonoid Ophiceras sp.yielded from bed 73 indicates the age of Triassic.Therefore,the Permian-Triassic boundary in Kejiao section is located in the middle of bed 72with a thickness of 20cm.
作者
蒋杨
吴会婷
肖异凡
杨廷禄
何卫红
王瀚
孙曦
吴顺宝
Jiang Yang;Wu Huiting;Xiao Yifan;Yang Tinglu;He Weihong;Wang Han;Sun Xi;Wu Shunbao(Faculty of Earth Sciences ,China University of Geosciences(Wuhan),Wuhan 430074,China;State Key Laboratory of Biogeology and Environmental Geology,China University of Geosciences(Wuhan),Wuhan 430074,China;School of Earth Sciences,East China Institute of Technology,Nanchang 330013,China)
出处
《地质科技情报》
CSCD
北大核心
2018年第6期65-73,共9页
Geological Science and Technology Information
基金
国家自然科学基金项目(41772016)
中央高校基本科研业务费专项资金区域引导专项(CUGQYZX1706)
