A calcisponge fauna occurs in uppermost Permian Conodont Clarkina meishanensis yini zone of the sequence exposed in the vicinity of Laibin, Guangxi Zhuang Autonomous Region, southern China. The fauna is dominated by o...A calcisponge fauna occurs in uppermost Permian Conodont Clarkina meishanensis yini zone of the sequence exposed in the vicinity of Laibin, Guangxi Zhuang Autonomous Region, southern China. The fauna is dominated by one thalamid species, Arnblysiphonella vesiculosa de Koninck, 1863, and one new scterosponge genus and species, Radiofibrosclera laibinensis gen. et sp. nov. They are associated with a few other accessory species, including the thalamid sponges Amblysiphonella laibinensis Deng, 1981, Colospongia sp., Polvcystocoelia sp., and the inozoan sponge Acoelia discontinua sp. nov. Though the individuals are abundant, the species diversity is very low. Without common calcisponge components of Changhsingian reefal faunas, the assembtage is interpreted as not a reefal fauna. The water depth at which they dwelled was less than 105 m, and more probably tess than 40 m. Its occurrence indicates a significant sea-level drop at the end of Late Permian Changhsingian Age.展开更多
通过对广西来宾菊花石的野外工作及其形貌观察、电子探针成分分析、偏光显微镜鉴定, 阐明了菊花石(chrysanthem um stone)的分布和形貌特征及其后生变化规律,认为菊花石主要由天青石、方解石和玉髓三种矿物组成。天青石(SrSO4)为原生矿...通过对广西来宾菊花石的野外工作及其形貌观察、电子探针成分分析、偏光显微镜鉴定, 阐明了菊花石(chrysanthem um stone)的分布和形貌特征及其后生变化规律,认为菊花石主要由天青石、方解石和玉髓三种矿物组成。天青石(SrSO4)为原生矿物,后经碳酸盐化,继而硅化形成方解石和玉髓。展开更多
基金supported by the National Natural Scientific Foundation of China(No.40172007,40472015,40802001,and 41372121)the key project from Chinese Academy of Sciences(No.KZ951B1-409)
文摘A calcisponge fauna occurs in uppermost Permian Conodont Clarkina meishanensis yini zone of the sequence exposed in the vicinity of Laibin, Guangxi Zhuang Autonomous Region, southern China. The fauna is dominated by one thalamid species, Arnblysiphonella vesiculosa de Koninck, 1863, and one new scterosponge genus and species, Radiofibrosclera laibinensis gen. et sp. nov. They are associated with a few other accessory species, including the thalamid sponges Amblysiphonella laibinensis Deng, 1981, Colospongia sp., Polvcystocoelia sp., and the inozoan sponge Acoelia discontinua sp. nov. Though the individuals are abundant, the species diversity is very low. Without common calcisponge components of Changhsingian reefal faunas, the assembtage is interpreted as not a reefal fauna. The water depth at which they dwelled was less than 105 m, and more probably tess than 40 m. Its occurrence indicates a significant sea-level drop at the end of Late Permian Changhsingian Age.