华南贵州罗甸纳水剖面宾夕法尼亚亚系各阶之界线(英文)

STAGE BOUNDARIES OF THE PENNSYLVANIAN IN THE NASHUI SECTION,LUODIAN OF GUIZHOU,SOUTH CHINA

贵州罗甸纳水剖面是研究宾夕法尼亚亚系牙形刺和各阶界线的良好剖面。经详细研究,从石炭系中间界线至石炭-二叠系界线,一个新的牙形刺序列为Gnathodus bilineatus bollandensis(密西西比亚系顶部),Declinog-nathodus noduliferus,Idiognathoidessulcatus sulcatus,Id.sinuatus,Id.corrugatus-Id.pacificus,Neognatho-dus symmetricus,Idiognathodus pri mulus-Neognathodus symmetricus,Idiognathodus pri mulus-Neognathodus bassleri,Idiognathoides sulcatus parva,Streptognathodus expansus,Idiognathoides ouachitensis,Diplognatho-dus coloradoensis,Di.ellesmerensis,Gondolella donbassica-Go.clarki,Idiognathodus podolskensis,Swadelina subexcelsa,Sw.makhlina-Sw.nodocarinata,Idiognathodus sagittalis,Streptognathodus cancellosus,St.graci-lis,St.guizhouensis,Idiognathodus si mulator,I.nashuiensis,Streptognathodus firmus,St.tenuialveus,St.wabaunsensis和St.isolatus(二叠系)等带。Declinognathodus noduliferus和Streptognathodus isolatus的首次出现分别代表宾夕法尼亚亚系和二叠系之底;Diplognathodus ellesmerensis,Idiognathodus sagittalis和I.si mula-tor的首现则可分别代表莫斯科阶(Moscovian),卡西莫夫阶(Kasi movian)和格舍尔阶(Gzhelian)之底界。作者较为详细讨论了巴什基尔阶与莫斯科阶以及卡西莫夫阶与格舍尔阶之界线,并认为以Diplognathodus ellesmerensis的首现作为巴什基尔阶(Bashkirian)与莫斯科阶之界线是目前最合适的标志。Diplognathodus ellesmerensis是一易于识别、分布广泛及层位稳定的牙形刺种,其产出又十分接近巴什基尔阶与莫斯科阶的传统界线,因此是划分此界线的良好标志。作者拟推荐纳水剖面为莫斯科阶底界之候选层型剖面,这一界线详细的工作正在大量采样分析和深入研究中,成果将在以后陆续发表。

The Nashui section of Luodian, Guizhou is a good section for the study of the Pennsylvanian conodonts and the stage boundaries. This paper displays a new conodont succession from the mid-Carboniferous through the Carboni-ferous-Permian boundary as follows： the Gnathodus bilineatus bollandensis （Uppermost Mississippian）, Declinognathodus noduliferus , Idiognathoides sulcatus sulcatus , Id. sinuatus, Id. corrugatus Id, pacificus, Neognathodus symmetricus, Idiognathodus primulus-Neognathodus symmetricus , Idiognathodus primulus Neognathodus bassleri , Idiognathoides sulcatus parva, Streptognathodus expansus, Idiognathoides ouachitensis, Diplognathodus coloradoensis , Di. ellesmerensis, Gondolella donbassica-Go, clarki , Idiognathoctus podolskensis , Swadelina subexcelsa , Sw. makhlina-Sw, nodocarinata, Idiognathodus sagittalis, Streptognathodus cancellosus, St. gracilis, St.guizhouensis, Idiognathodus simulator, I. nashuiensis, Streptognathodus firmus, St. tenuialveus, St. wabaunsensis and St. isolatus （Permian） zones. The bases of the Declinognathodus noduliferus Zone and the Streptognathodus isolatus Zone are the bases of the Pennsylvanian and Permian, respectively. The first occurrences of Diplognathodus ellesmerensis, Idiognathodus sagittalis and I. simulator represent the bases of the Moscovian, Kasimovian and Gzhelian, respectively. In addition, the Bashkirian-Moscovian boundary and the Kasimovian-Gzhelian boundary are discussed in detail. The first occurrence of Diplognathodus ellesmerensis as the beginning of the Moscovian Stage is a good proposal among proposals for the Bashkirian-Moscovian boundary. Diplognathodus ellesmerensis is easy to be recognized, widely distributed in the world, and has the stable horizon. Its first occurrence is very close to the traditional Bashkirian-Moscovian boundary. We suggest that the Nashui section of Luodian, Guizhou to be a candidate for the global stratotype section and point for the base of the Moseovian Stage. The further study on this boundary is carrying out and more detailed proposal will be submitted later.