[关键词]
[摘要]
石炭纪密西西比亚纪是四射珊瑚相对繁盛的时期。维宪晚期至谢尔普霍夫期, 受晚古生代大冰期和海西运动的影响, 西欧等不少地区的海相沉积发生相变, 四射珊瑚记录稀少。华南在此时仍广泛发育浅海相碳酸盐岩沉积, 含有丰富的四射珊瑚化石记录。通过对安徽省巢湖地区和州组四射珊瑚的研究, 共鉴定出11属15个种, 其中包含2比较种1、亲近种和3未定种。珊瑚动物群面貌具有典型华南大塘晚期四射珊瑚的特征, 属于Aulina rotiformis带(原Yuanophyllum带上部), 年代为谢尔普霍夫期。和州组的四射珊瑚组合可与湘中梓门桥组上部 Yuanophyllum带的Neoclisiophyllum yengtzeense–Koninckophyllum stellatum亚带和Lophophyllum lophyphylloidea亚带对比 , 也可与黔西赵家山组的 Palaeosmillia murchisoni murchisoni 组合带和 Lithostrotion decipiens–Dibunophyllum bipartitum组合带对比。根据珊瑚动物群的组成、生长形态、共生关系和围岩的岩性特征, 可判断动物群生活在相对浑浊、局限、富营养化的近岸浅海环境中。
[Key word]
[Abstract]
The Mississippian is a subperiod of the Carboniferous during which the rugose corals prospered. During the late Visean and Serpukhovian, the onset of the Late Palaeozoic Ice Age, coupled with the Hercynian Orogenic movement, resulted in rapid sea-level changes. Regions in the western Palaeotethys, such as the present-day western Europe, were affected by the sea-level fluctuations and facies changes recorded in marine sedimentary successions, resulting in the punctuation and scarcity of rugose coral fossil record. South China, however, was less affected, and shallow marine carbonate successions with abundant rugose coral fossils were widespread and well-developed. From a collection of coral fossils recovered from the Hezhou Formation near Chaohu, Anhui Province, Lower Yangtze region, a total of 15 species belonging to 11 genera, including two species conformis, one species affinis and three species indeterminabilis are recognized. The coral fauna consists of elements of the late Datangian type from South China, and can be assigned to the Aulina rotiformis Zone (the upper part of the former Yuanophyllum Zone), inferring the Serpukhovian age for the Hezhou Formation. The assemblage correlates well with the Neoclisiophyllum yengtzeense–oninckophyllum stellatum subzone and Lophophyllum lophyphylloidea subzone of the Zimenqiao Formation in central Hunan, and to the Palaeosmillia militaris Zone and Lithostrotion decipiens–Dibunophyllum bipartitum Zone of the Zhaojiashan Formation in western Guizhou. The size and growth-form, the symbiotic relationship of the corals, and the taxonomical composition of the coral assemblage indicate that the fauna lived in a relatively turbid, restricted and eutrophic nearshore shallow marine environment.
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[基金项目]
国家自然科学基金(41902023)和中国科学院青年创新促进会(2022311)联合资助