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在对鄂西宜昌王家湾和分乡、黔北桐梓红花园、黔东北松桃陆地坪 4条剖面的相关地层和主要门类化石做了新的无间断采集和重新鉴定笔石和腕足动物这两个重要化石门类的基础上 ,发现奥陶纪最末期—志留纪最早期的完整笔石序列与腕足动物等新的化石材料 ,初步了解奥陶纪末集群灭绝后生物幸存的基本特征。经过选择 ,特推荐宜昌王家湾公路旁穿越奥陶 -志留纪界线地层剖面作为建立国际赫南特亚阶的首位候选 (leading candidate)层型 ,并推荐桐梓红花园相关剖面作为辅助候选 (auxiliary candidate)层型。对建立全球赫南特亚阶界线层型的基本条件和国外相关剖面的优缺点作了分析。本文所识别的赫南特亚阶相当于两个笔石带 :下部 N ormalograptus ex-traordinarius- N.ojsuensis带和上部 N.persculptus带。典型的 H irnantia动物群的整体地质历程为奥陶纪最末期 ,相当于 N ormalograptus extraordinarius- N.ojsuensis带和 N.persculptus带的一部分。
A new non-stop acquisition and re-evaluation of penoliths and brachiopods were carried out on the related strata and main categories of fossils in 4 sections of Wangjiawan and Fenxiang in Yichang, western Hubei Province, Tongzihong Garden in Guizhou Province and Songtao Ping in northeastern Guizhou Province Based on the important fossil categories, we found out the earliest complete records of petroclival sequences and brachiopods and other new fossil materials from the end of Ordovician, and finally understand the basic features of biological survival after the end of Ordovician cluster extinction. After selection, it is recommended to cross the line of Ordovician-Silurian boundary strata along Yichang Wangjiawan Highway as the first candidate of establishing the international Hernández-Euphorbiaceae and suggest the relevant section of Tongzihong Garden as a supplementary candidate candidate The basic conditions for establishing the global Hernantea boundary line strata and the advantages and disadvantages of relevant overseas sections are analyzed. The Hernándezian sequence identified here corresponds to two peninslids: the lower N ormalograptus ex-traordinarius-N. ojsuensis zone and the upper N. persicus band. The overall geologic course of a typical H irnantia fauna is that of the Late Ordovician and corresponds to a part of the Nömalograptus extraordinarius-N. ojsuensis zone and the N. peccerus zone.