摘要
作为古生代最后阶段的乐平统可划分为２个阶和４个亚阶，暂以逼近自然界线的Ｃｌａｒｋｉｎａｐｏｓｔｂｉｔｔｅｒｉ带之底为下界；在二叠纪形成了栖霞期之前和吴家坪期之前两个超序界面，乐平世海侵居于二叠—三叠纪超序的低水位体系，乐平世末的海泛淹没了古特提斯区的残留陆棚；二叠纪末的生物大绝灭形成规模和性质不同的两幕：茅口期末全球性海退使栖居地丧失而导致地方性类群和远洋浮游生物灭亡的前乐平统海洋动物灾变事件，和乐平世末全球性急速海侵破坏了残留陆棚，引发生物量锐减和高级类群的消亡。
As the last series of Paleozoic Era, the Lopingian is divisible into two stages and four substages, with the base of Clarkina postbitteri Zone as its lower boundary. The pre-Chi hsian Stage and pre-Wuchiapingian Stage regression resulted in globally recognizable boundaries of supercycle during Permian Period. A major transgression appeared as the initial part of Permian-Triassic supercycle during Lopingian Epoch and flooded over all relic shelves in Paleotethys at the end of this epoch. The end-Permian Mass Extinction comprises two distinct phases: a pre-Lopingian crisis of endemic benthos and pelagic faunas that occurred in coincidence with global regression ; and an end-Lopingian event characterized by sharp declination of biomass and extinction of major fossil groups, and corresponding with a worldwide rapid flooding.
出处
《古生物学报》
CAS
CSCD
北大核心
1995年第4期410-427,共18页
Acta Palaeontologica Sinica
基金
国家自然科学基金
