摘要:
一、概述黔西南二叠纪生物礁形成于早二叠世茅口中晚期,延续至晚二叠世,全盛期在长兴期,属台地边缘生物礁类型,于罗甸、紫云、望漠、贞丰、册亨一线断续出现(图1)。礁带厚约100—300m,宽2km,延伸200km以上,并分别进入广西、云南两省,呈北东 向星点状展布。造礁生物以块状海绵、水螅为主,次有苔藓虫、管壳石和床板珊瑚,具原地埋藏特征。礁体中造礁生物量达45—80%,其中海绵类达25—60%,非骨骼蓝藻依附造礁生物和颗粒粘结缠绕成藻包壳,形成抗浪格架。其间附礁生物丰富,主要有棘皮、腕足、有孔虫、(竹蜓)、绿藻、腹足、介形虫、瓣鳃等,它们与灰泥基质、礁砾屑一起充填于礁架孔隙之中。岩石类型主要为骨架岩、障积岩、粘结岩及它们之间的过渡型岩石。
Abstract:
The Permian organic reef in Southwest Guizhou Province began to be formed in the middle-late Maokou age of Early Permian and continuously developed until Late Permian.The organic reef may be considered as a kind of margin-plat form reef.The reef-building zoolites were chiefly Spongia and Hydrozoa, secondly Tabulate and Bryozoa. However, Cyanophyta which played an important part in the process of reef-building took shape of’ cohesion and encrustation in appearance. There were also some commensaliam in the reef，such as Crinoidea, Brachyopoda, Foraminfera, Fusulinids, Gastriopoda,Chlorophyta and so on.They correspondingly formed frame- building rocks, frame building obstructed rocks, obstructed Fucks, cohesive rocks and bioclastic limestone,
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