龙门山唐王寨地区逆冲推覆体生物地层学研究

BIOSTRATIGRAPHICAL RESEARCH OVERTHRUST NAPPE OF TANGWANGZHAI AREA IN LONGMEN MOUNTAIN

推覆体的泥盆系地层生物繁盛,门类众多。下、中泥盆统有丰富的腕足类,次为珊瑚、双壳类、三叶虫和角石;中、上泥盆统碳酸盐地层中发育大量牙形石,特别是Palmatolepis极为丰富。经分析研究划分出11个化石带和化石组合,聚类分析谱系图表现出来的10个化石组合与它吻合,可进行区域对比。在此基础上,对泥盆系的地层单元及下、中、上泥盆统之间的界线进行了划分,对化石特征进行了描述。

Living things throve in Devonian strata of the nappe, and their species were numerous. In Lower and Middle Devonian there were rich brachiopods, and then corals, bivalves, triobites and cephalopods. The carbonate strata in Middle and Upper Devonian contained abundant conodonts, specially Palmatolepis. Through analysis and research, we have divided the fossils into ten fossil zones and assemblages. The ten fossil assemblages showedin the dendrogram of cluster analysis tally with them, by which we can make regional correlation. According to this, we have classified stratigraphical units, defined the boundary of Devonian series, and described the characteristics of fossils.