重庆綦江早奥陶世特马豆克阶藻类增长及其指示意义

Early Ordovician Tremadocian algae growth in Qijiang area of Chongqing and its indicative significance

探讨重庆市綦江区观音桥剖面早奥陶世特马豆克阶藻类增长及其指示意义。通过对观音桥剖面连续发育的奥陶纪地层进行镜下藻类统计研究,并结合其他学者关于奥陶纪的古大洋及古大气演化的研究结果,认为大型藻类丛生藻的出现对藻类的辐射具有极好的指示意义;藻类的繁盛促使奥陶纪生物辐射事件第一幕的发生,在奥陶纪生物辐射事件第一幕高潮之后,形成了一个新的生态体系,藻类数量与介壳动物数量处于一个较小变化幅度的稳定时期;藻类在海洋中的爆发和极速增长,光合作用导致大量氧气释放并部分溶于海洋之中,与部分研究者所得到的特马豆克阶古海洋氧化的结果一致。特马豆克阶藻类的增长,促进了氧化事件,氧化事件又推动生物辐射事件,三者间的促进关系代表了生物辐射第一幕的早期阶段。

Through the statistical study of microscopic algal from the continuous Ordovician strata in Guanyinqiao section,combined with the research results of other scholars on the evolution of the ancient ocean and ancient atmosphere of the Ordovician,the growth of early Ordovician Tremadocian algae and its indicative significance in Guanyinqiao section,Qijiang County,Chongqing is discussed.It is considered that the appearance of the macro-alga cluster has a very good indication for the radiation of algae.After the climax of the first act of the Ordovician biological radiation event,a new ecological system was formed.The number of algae and the number of crustaceans were in a stable period with only a small range of change.Algae burst and grew rapidly in the ocean,and photosynthesis led to the release of large amounts of oxygen and partial dissolution in the ocean,which is consistent with the results of Tremadocian ancient ocean oxidation obtained by some researchers.The growth of Tremadocian stage algae promotes the oxidation event,which in turn promotes the biological radiation event.The promoting relationship among the three represents the early stage of the first act of biological radiation.