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一、前言二叠系与三叠系间的界限问题是研究古生代同中生代两大时期生物的更替以及地史变革的重要问题。二叠、三叠系界线问题的焦点在于所谓过渡层问题。即该层含有下三叠统的菊石、瓣鳃的同时还残存有晚古代生代“二叠纪型”的腕足类。自六十年代起,在国际上就广泛引起地质古生物学学的浓厚兴趣,特别是对外高加索、伊朗北就和中部、巴基斯坦盐岭,克什米尔的研究更引人注目。在国外如Kummel & Teichert,Nakazawa et al,Tozer、Taraz等曾专门从事这一专题的研究,并于1973年出版了论文集。我国赵金科等亦从事过这
I. Preface The boundary issue between Permian and Triassic is an important issue for studying the alternation of biology during the Paleozoic and Mesozoic Dynasties and the change of geography and history. The focus of Permian and Triassic Boundary Problems lies in the so-called transitional issue. That is, this layer contains the ammonification of the Lower Triassic, while the gills of the petals also retain the Late Permian “Permian” type of brachiopods. Since the 1960s, the international community has aroused great interest in the geology and paleontology. In particular, the studies on the Transcaucasus, Iran’s North and Central Iran, Salt Mountain in Pakistan and Kashmir have drawn more and more attention. In foreign countries such as Kummel & Teichert, Nakazawa et al., Tozer, Taraz et al. Have devoted themselves to the research of this topic and published theses in 1973. Our country Zhao Jinke also engaged in this