陕南川北志留系兰多维列统特列奇阶宁强组的生物礁  

The Reef Complexes of Ningqiang Formation, Telychian,Ningqiang Guangyuan Area

作　　者：李越[1] 陈旭[1] 

机构地区：[1]中国科学院南京地质古生物研究所

出　　处：《沉积学报》1998年第3期124-131,共8页Acta Sedimentologica Sinica

基　　金：中国科学院古生物和古人类学科基础研究特别支持项目

摘　　要：志留纪兰多维列世（Ｌｌａｎｄｏｖｅｒｙ）扬子地台持续上升。特列奇期（Ｔｅｌｙｃｈｉａｎ）ｇｒｉｅｓｔｏｎｉｅｎｓｉｓ笔石带上部至ｓｐｉｒａｌｉｓ－ｇｒａｎｄｉｓ带代表的时限内，地处扬子地台西北缘的宁强湾，在温暖浅海的环境中沉积了宁强组巨厚的泥页岩，其中夹含８套碳酸盐岩。在与之对应的８期小型局限碳酸盐岩台地的不同部位建造了生物礁和生物滩。生物礁的类型包括骨架礁、生物层和灰泥丘。生物礁群落由底栖固着的造礁珊瑚、苔藓虫、海百合、藻类、层孔虫，以及非固着的附礁生物腕足类、鹦鹉螺、三叶虫等组成。通过宁强广元地区不同地点和层位的生物礁组合分析，论述它们在生态组合、生长形状和发育过程中的多样性。The uplifting of whole Yangtze platform occured by the end of Llandovery(Telychian),execpt several bays around the margin of the platform.The Ningqiang Formation consists of more than 2000 m shales and limestones with faunas form upper griestoniensis Zone to spiralis grandis Zone.The limestones within this unit may be subdivided into 8 stages according to their origination in ascending order.Reef complexes developed at different sites on limited carbonate platforms.Reefs,biostromes and lime mudmounds cropped out in the different subfacies of the reef complexes.The important reef complexes′ building organisms include corals,bryozoans,pelmatozoans,algea and stromatoporoids,and the attaching reefal organisms are brachiopoda,nutiloidea,trilobite,etc..The features of the reefal organisms are changable in temporal and spatial distribution.Analysis of typical reef complexes indicate that they are variable in association,shape and growth process.The termination of all limited platforms and reef complexes depends on the covering of mudstones.

关 键 词：生物礁 碳酸盐岩 局限台地 宁强组 志留系 地层 

分 类 号：P588.248[天文地球—岩石学] P534.43[天文地球—地质学]