晚震旦世陡山沱期后生生物群的古生态环境探讨  

Palaeoecology and fossil preservation of the early metazoan biotas during the Doushantuoan (Late Sinian)

作　　者：杨瑞东[1] 

机构地区：[1]南京大学地球科学系,江苏南京210093

出　　处：《岩相古地理》1999年第5期53-59,共7页

基　　金：贵州省科委基金资助

摘　　要：早期后生生物群是当前古生物学研究热点之一。我国上扬子区的庙河生物群和瓮安生物群是震旦纪的重要生物群，而生物群是怎样繁盛和埋藏保存是研究早期后生生物群的一个重要方面。作者研究认为瓮安生物群是由于洋流上升提供了大量的ＳｉＯ２ 和Ｐ２Ｏ５ 等养分，使生物在台地边缘大规模繁盛，其海水由于富ＳｉＯ２ 和Ｐ２Ｏ５ 所引起强烈的磷酸岩化及硅化作用，使大量的生物尸体被快速矿化，形成具有抗水动力强的骨架，避免水动力和氧化作用的破坏，因此，矿化作用是生物体保存为化石的另一个重要因素。最后。This approach addresses the current research in palaeoecology which focuses on the early metazoan biotas in China during the Doushantuoan (Late Sinian). Two important categories have been classified for the Sinian biotas: Miaohe and Weng' an biotas on the Upper Yangtze platform. Of particular significance is why and how these biotas flourished and were preserved during geological time. The author contends that abundant SiO_2 and P_2O_5 supplied by the upwelling currents permitted the living organisms to get thriving on a larger scale on the margins of the platform. The steady increase in SiO_2 and P_2O_5 resulted in intense phosphatiza- tion and silicification; that is to say, the abundant organic remains were rapidly phosphatized and silicificated, and got out of oxidization and decomposition. It can be seen that mineraliza- tion (phosphatization, silicification and manganesation) may be interpreted as an important factor in the preservation of the organic remains as fossils, and that the Upper Yangtze area is a favourable region in China for the flourishing of organisms during the Doushantuoan (Late Sinian).

关 键 词：后生生物群 古生态 庙河生物群 古生物 古地理 

分 类 号：Q911.6[天文地球—古生物学与地层学] P531[生物学—古生物学]