摘要
本文将黔南、桂西北上石炭统Pseudoschwagerina带与下二叠统Misellina claudiae带间连续沉积的百米至千米厚的地层划分为花贡碎屑岩相,平川灰岩-泥灰岩相及常么纯灰岩相。各相区的地层划分,化石带及对比如表1,2,3。该套地层包括下部Pamirina-Staffella和上部由Robustoschwagerina,Nagatoella,Nankinella等组成的两个具不同性质的生物群,它们的时代分别为晚石炭世末和早二叠世初,为石炭系与二叠系分界的标志。由于两个生物群均含菊石Propopanoceras,从而表明该菊石是跨系的,它比苏联乌拉尔地区萨克马尔组(狭)的Propopanoceras的出现时期要早。
The strata deposited continuously between the Carboniferous and Permian in southern Guizhou and northwestern Guangxi may be divided into three sedimentary facies:Huagong,Pingchuan and Changmo facies.The paper discusses the characteristics of the three facies and the Carboniferous-Permian boundary.The proposed stratigraphic sequence is shown in the following table.This sequence of strata consists of two faunas that are closely related but distinct from each other.The lower fauna is represented by the Pamirina-Staffella zone,containing China’s typical terminal Late Carboniferous fossils,such as Sphaeroschwagerina and Biwaella.Its age is assigned to the Uppermost Carboniferous.The upper fauna is represented by the Nagatoella-Nankinella zone in Pingchuan,Robustoschwagerina-Pseudofusulina inusitata zone in Changmo and Robustoschwagerina-Nagatoella zone in Huagong.Those fusulinid zones all contain the typical elements of the fauna of the Early Permian Qixia Formation such as Nagatoella,Nankinella,Parafusulina and Misellina.The appearance of these elements of the fauna is primitive,but it shows the nature of a new fauna.Its age is assigned to the base of the Lower Permian.The two faunas both contain Propopanoceras,indicating that the ammonite horizon spans the Carboniferous—Permian,with the lower boundary of its stratigraphic range being lower than in the Urals.The Carboniferous—Permian boundary is placed between the two faunas.
作者
龙家荣
Long Jiarong(Regional Geological Survey Party,Bureau of Geology and Mineral Resources of Guizhou Province)
出处
《地质学报》
1985年第3期191-202,共12页
Acta Geologica Sinica
