本项目通过扬子区重要剖面地质学和地球化学研究精确确定二叠-三叠纪之交各类地质事件⑸南群笏承蚣安煌爬嗌锔娴奈恢茫徊⒔录夭恪⒍康夭恪⑸锏夭愫凸派治鱿嘟岷希范康匮橹ぱ芯壳诟鞯刂适录⑸牡仁毙裕教值刂适录вσ鸬幕肪潮浠圆煌厍锔嬖斐捎跋斓耐恍院陀氩煌嘈蜕锵嗷プ饔玫牟钜煨浴

A lot of geological events happened during Late Permian, biotic mass extinction went with them. According to research in some sections of South china, it is found that the biotic extinction carry through all Late Permian, but the biotic extinction was very evident in two stages (the early Wujiapingian and the end of Changsingian); further more, the two stages of the biotic mass extinctions evidently related with volcanic break forth in Emeishan area. Analysis of tuff shows that some important geological events were likely to occur in sea floor in the end of Permian. These things inosculated with the phenomena, which the extinction of sea biotic was more evident than continental biotic during Late Permian. This indicates that volcanic break forth in seabed, going with plate cracking, may be dominant factor of the biotic mass extinctions.