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通过对湖北宜昌界岭剖面中—上奥陶统庙坡组的几丁虫进行系统古生物学与生物地层学研究,鉴定出几丁虫18属43种。将庙坡组的几丁虫识别为Laufeldochitina stentor几丁虫带,并进一步划分为Cyathochitinasp.3和Armoricochitina granulifera两个亚带。除在庙坡组下部发现几丁虫以外,首次在庙坡组上部发现大量保存精美的几丁虫化石,填补了该层段以及华南该时段几丁虫研究的空白,丰富了华南晚奥陶世早期几丁虫的多样性记录。首次在华南报道冈瓦纳北部的典型分子Lagenochitina ponceti Rauscher,以及波罗的地区的特征分子Laufeldochitina stentor(Eisenack)和Cyathochitina sebyensis Grahn。根据几丁虫组合面貌特征及相关生物地层研究,认为晚奥陶世初期华南扬子区几丁虫的生物地理分区不明显,与波罗的、冈瓦纳北部、劳伦大陆以及阿凡隆尼亚板块皆具有一定的相似性。同时,L.stentor,C.sebyensis以及A.granulifera等波罗的地区典型分子在华南庙坡组的首次报道,增强了达瑞威尔晚期至桑比早期华南与波罗的地区地层对比的潜力。
A systematic palaeontology and bio-stratigraphic study of chitin found in the Middle-Upper Ordovician Miapo Formation of the Lingling Section, Yichang, Hubei Province, identified 43 genera and 18 genera. The Chilo pests in the Miaofeng group were identified as Laufeldochitina stentor chitin bands and further divided into two sub-bands: Cyathochitinasp.3 and Armoricochitina granulifera. In addition to the discovery of chitin in the lower part of the Miaopo Formation, a large number of finely preserved chitin fossils were found in the upper part of the Miaopo Formation for the first time, filling up the gaps in this interval and the research on chitin in this period in southern China, enriching the late Ordovician Early records of the diversity of chitin in the world. For the first time in South China, Lagenochitina ponceti Rauscher, a typical member of the north of Gondwana, and Laufeldochitina stentor (Eisenack) and Cyathochitina sebyensis Grahn, characteristic of the Baltic region, were reported. According to the combination of morphological characteristics and related biostratigraphic studies, it is considered that the biogeographical division of the chitinian in the Yangtze region in the early stage of Late Ordovician is not obvious. The biogeography of the chitin bugs in the northern part of the Baltic, Gondwanaland, Asian plate has a certain similarity. At the same time, the first reports of typical molecules of the Baltic region, such as L.stentor, C. sebyensis and A. granulifera, in the Miapo Formation in southern China enhanced the potential for stratigraphic correlation between the Darwinian period and the early Southern China-Baltic region .