弗拉斯—法门期之间的生物绝灭事件

FRASNIAN-FAMENNIAN EXTINCTION EVENT

晚泥分世弗拉斯—法门期(Frasnian—Famennian)之间存在一次全球性生物绝灭事件(简称F—F事件).本文简介了F—F事件的生物绝灭、事件界线、事件成因及近年国内研究情况弗拉斯末期,大量的海生无脊椎动物,尤其是热带、亚热带浅水区造礁及附来礁生物绝灭.绝灭的生物包括层孔虫、珊瑚、腕足类、竹节石、三叶虫、菊石及浮游植物等门类中的很大一部分成员.F－F件发生在牙形石的palmatolepis gigas带和Palmatolepis triangularis带之间,最可能发生在Palmatolepis gigas最上亚带.事件发生的原因有各种不同解释:1)海平面变化说;2)古气候变冷说;3)天文事件说等.目前国内对F—F事件的研究较少,侯鸿飞、王士涛(1985)曾总结了华南等地F—F界线附近的生物群变化.笔者等研究了西秦岭中带F—F事件,探讨了这次事件的可能成因.

The extinction event occurred during the Frasnian-Famennian (F-F event) has been recognized as a global event. At the end of the Frasnian stage there was an extinction of animals on a huge scale in the shallow seas covering much of the continental areas of the world. Most members of the animals, such as corals, stromatoporoids, brachiopoids, trilobites, tentaculitids, and ammonoids went extinct. The horizon of the event is in the gigas-triangularis zonal interval. Three causes have been suggested for this extinction. They are : fluctuation of sea level, climatic variation and astronomical event. F-F event occurring in South China and Western Qinling mountains is introduced in this paper.