论石炭——二叠系界线

On the Boundary between Carboniferons and Permian in Southeastern Yunnan and Western Guangxi

在滇东南和桂西等地,广泛发育石炭—二叠系界线地层。它是研究生物的演化、地层的划分与对此和建立界线层型剖面的理想地区。笔者在砚山、广南、麻栗坡及那坡等地实测包含马平组的界线地层剖面4条。它们富含蜒类、四射珊瑚和牙形剌化石。根据生物、地史特征与全球地层对比,认为:石炭—二叠纪的界线应置于三原野假希瓦格蜓带或尤登氏假希格蜓带之底,或是以假希瓦格蜓亚科的分子的始现作为二叠纪的开始是比较合理的,也是在全球范围内可行的。

The boundary strata of Carboniferous and Permian are widely outcropped in Southeastern Yunnan and Western Guangxi,which is the ideal area for Studying the biological evolution,stratigraphic division and correlation ond boundary strato-typical foundation. The authors have surveyed 4 stratigraphic sections containing'Maping Group'in Yanshan,Guangnan,Malipo and Napo.These sections contain rich fusulinids,Co.rals and conodonts.This paper is based on the feature of fusulinid fauna and geohistory and stratigraphic correlation in the globe.It suggests to take the bottom of Pseudoschwagerina miharanaensis—P.uddeni zone as the Boundary.In other words,the first appearance of any membey of Peudoschwagerininae in the section Should be taken as the begining of Permian.Perhaps this may be appropriately accepted in the world.