新疆南天山库车河地区二叠──三叠系界线探讨

Studies on the Permian-Triassic Boundary in Kuqa River Basin of South Tianshan Mountains, Xinjiang

新疆南天山库车河地区出露着二叠──三叠系的连续剖面，剖面中地层界线清楚，化石较为丰富，在上二叠统比尤勒包谷孜群中发现了安加拉大陆晚二叠世植物群的典型代表“Ｃａｌｌｉｐｔｅｒｉｓ”ｚｅｉｌｌｅｒｉ和俄罗斯库滋涅茨克煤田上二叠统顶部的特有种Ｙａｖｏｓｋｙａｍｕｎｇａｔｉｃａ。而下三叠统俄霍布拉克群的植物化石具明显的中生代面貌。因此，库车河地区海西期花岗岩之上覆盖着晚二叠世晚期地层，它与下三叠统俄霍布拉克群连续沉积，二者为整合接触关系。该区二叠──三叠系界线应置于俄霍布拉克群底部的底砾岩。

There is a continuous section of the Permian and Triassic systems in the Kuqa river basin of the South Tianshan Mountains, Xinjiang. The stratigraphic boundaries are clearcut and fossils are richer in the section.“ Callipteris”zeilleri and Yavoskya mungatica were found in the Upper Permian Biyoulebaoguzi Group. The former is a typical representative of the late Permian flora in the Angara land and the latter is a special species at the top of the Upper Permian in the Kuzinicik coal field of Russia. The Plant fossils in the Lower Triassic Ehuobulake Group show a conspicuous Mesozoic look. On the Hercynian granite along the Kuqa river, therefore . is the late Late Permian stratum, which is continuously joined to the Lower Triassic Ehuobulake Group. And both of them are in conformity. The Permian-Triassic boundary in the region should be put at the bottom conglomenates in the base of the Ehuobulake Group. A fossil mark of division between them is the disappearance of the“Callipteris”zeilleri-Comia flora .