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我国贵州东部乌溜-曾家崖凯里组剖面作为世界早-中寒武世界线层型侯选剖面,产出良好保存的大型无脊椎动物化石(尤其是三叶虫)。因此,更加详细研究该剖面海洋疑源类的生物地层非常重要,将提供围绕界线的生物和环境变化的细微记录。乌溜-曾家崖剖面凯里组的疑源类划分两个组合,它们是凯里组0-52m的Leiomarginata si mplex-Fi mbriaglomerella membranacea组合和52-140m的Cristallinium cambriense-Heliosphaeridiumnodosum-Globosphaeridiumcerinum组合。140-214m仅有很少疑源类标本,可能因为凯里组上部以白云岩为主,不适宜有机壁微体化石的保存。距凯里组底部往上约52m处疑源类组合出现重大变化,无疑为解释沉积环境提供重要资料。两疑源类组合间界线,位于52.3-52.7m,此稍低于被三叶虫Oryctocephalusindicus首现所指示的全球寒武系第5阶潜在层型剖面界线。
The Wuliu-Zengjiaya Carey Formation section in the eastern part of Guizhou Province, China, serves as a well-preserved large-scale invertebrate fossil (especially the trilobite) as a candidate for the Early Cretaceous Boundaryline Profile. Therefore, a more detailed study of the biogenic stratigraphy of the oceanic suspected source of this profile is very important and will provide a subtle record of the biological and environmental changes that surround the boundary. The Wuyou-Zengjiaya profile of the Kaili Formation is divided into two groups, Leomarginata si mplex-Fi mbriaglomerella membranacea (0-52m) and Cristallinium cambiense-Heliosphaeridium nodosum-Globosphaeridium cerinum (52-140m) in the Carey Formation. There are only a few suspected samples of 140-214m, probably because dolomite is the main part of the Carey Formation, which is not suitable for preservation of organic wall microfossils. Significant changes in the composition of the suspected source groups about 52 m above the bottom of the Kaili Group undoubtedly provide important information for explaining the sedimentary environment. The boundaries of the two suspected source assemblages range from 52.3 to 52.7 m, which is slightly lower than the global Cambrian Cambrian 5th-order potential stratigraphic line indicated by the first appearance of the trilobite Oryctocephalusindicus.