贵州紫云扁平剖面早二叠世非■有孔虫动物群

THE EARLY PERMIAN NON-FUSULINID FORAMINIFER FOSSILS AND BIOZONES FROM THE BIANPING SECTION,ZIYUN OF SOUTHERN GUIZHOU

贵州紫云扁平剖面紫松阶上部—罗甸阶非■有孔虫动物群由25属82种(含相似种、亚种而不含未定种)构成,其中7属(Cribrogenerina、Nodosaria、Glomospira、Tetrataxis、Palaeotextularia、Climacammina及Globival-vulina)的物种分异度最高,合计占总种数的71%;该动物群自紫松期开始发育,在隆林期类群构成发生显著变化并繁盛至罗甸早期,在罗甸中晚期明显衰落。研究剖面由下至上可划分为Cribrogenerina celebrata-C.hemispaera间隔带、Glomospira-Nodosaria富集带(又可进而分为Geinitzina postcarbonica-Globivalvulina cyprica间隔亚带、Climacamminaelegantula延限亚带)、Lasiodiscus-Eotuberitina间隔带。

The Bianping section in Ziyun County, Guizhou Province, is one of the important Permian sec- tions in southern China where detailed study of non-fusulinid foraminifers and their biostratigraphy has been carried out. Based on material collected from the Bianping section, a detailed investigation has been conducted to study the paleontology and biostratigraphy of non-fusulinid foraminifers. A total of 82 species belonging to 25 genera of non-fusulinid foraminifers have been identified in the Early Permian succession. The Early Permian non-fusulinid foraminifer assemblage in the Bianping area can be divided into three zones and two subzones. These are, in an ascending order, the Cribrogenerina celebrata-C, hemispaera Zone （interval zone）, the Glomospira-Nodosaria Zone （abundance zone） including the Geinitzina postcar- bonica-Globivalvulina cyprica Subzone （interval subzone） and the Climacammina elegantula Subzone （range subzone）, and the Lasiodiscu^Eotuberitina Zone （interval zone）. The results of this study demon- strate that non-fusulinid foraminifers in the Bianping area diversified in the early and middle Early Permi- an, and declined in the late Early Permian, with an interval of significant turnover in between.