赣东北晚三叠世安源组植物群

Late Triassic Anyuan Flora from Northeast Jiangxi Province,South China

通过对赣东北上饶地区宋村、司铺和东山村3条剖面保存的植物化石全面研究,讨论了赣东北安源组地层分布特征,安源植物群的组成、特征及其地质时代.鉴定并统计安源植物群有28属60种,其中苏铁类及本内苏铁类11属33种,占植物群总数55.0%,居植物群首位;真蕨类5属11种,占植物群总数18.3%,居植物群第2位;种子蕨4属6种,占植物群总数10.0%;有节类2属3种,占植物群3.0%,然而丰度高;银杏类4属5种,占8.3%,松柏类及繁殖器官2属2种,占3.4%.该植物群归于晚三叠世Ptilozamites-Anthrophyopsis组合.安源植物群组成分子中,喜湿植物14种,占植物群23.3%,耐旱植物46种,占植物群76.7%,属于半潮湿型.喜热植物45种,占植物群75.0%,广温植物15种,占植物群25.0%,属炎热型,代表中国南方滨海型热带亚热带半潮湿气候.

The composition, features and geological time of the flora in the Anyuan Formation, Shangrao City, Jiangxi Province have been studied. The fossil plants obtained are identified to be of 60 species belonging to 28 genera： 26 known species, 10 similar species and 24 undetermined species. Of the Anyuan flora, Cycadophytes accounts for 55%, Pteridphytes, 18. 3%, Pteridospermophytes, 10%, Ginkgophytes, 8. 3%, Coniferophytes, 3.4%. The flora should be classified as Ptilozamites-Asthrophyopsis assemblage in the lower part of the Dictyophyllum-Clathropteris series. This important Upper Triassic flora is widely distributed in Sweden, Germany, eastern Greenland, Russia, Vietnam and Japan. In China, it has been found in the Xujiahe Formation of Sichuan, Shazhenxi Formation of Hubei, Lalijian Formation of Anhui, Fanjiatang Formation of Jiangsu, Dakeng Formation of Fujian, Wuzao Formation of Zhejiang and so on. The philotherm of the flora represents hot and semi hu mid climate of South Ch/na coastal areas.