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60年代之前,人们已注意到大量生物(特别是底栖造礁生物)均相继消亡于弗拉斯阶 (Frasnian Stage)晚期,然后在法门阶(Famennian Stage)出现了长时期的生物萧条。当时,人们并未意识到这是一次重大的生物绝灭事件,当然也不可能认识到它的全球性质。直到70年代初,加拿大学者 D.J.Mclaren(1970)首次提出,在晚泥盆世中极短时间内发生的生物灭绝,看来是一次全球性巨大生物绝灭事件,并且认为这次事件可能是由天体撞击造成的。此后,各国学者越来越关注弗拉斯阶-法门阶事件(Frasnian-Fame-
Before the 1960s, it was noticed that a large number of creatures, especially benthic reef creatures, died one after another in the late Frasnian Stage, followed by prolonged biological depression in the Famennian Stage. At that time, people did not realize that this was a major biological extinction event, of course, it is impossible to recognize its global nature. It was not until the early 1970s that the Canadian scholar DJ McLaren (1970) first proposed that the biological extinction occurring within a very short time in the Late Devonian appears to be a huge global extinction event and that this incident may be caused by Caused by the impact of celestial bodies. Since then, scholars from various countries have paid more and more attention to the Frasnian-Fame-