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对甘肃华亭延安组植物化石进行了宏观形态和表皮构造分析,经鉴定共有24属49种。该植物群组成为:真蕨纲(28.6%)、银杏纲(38.8%)繁盛,松柏纲(16.3%)、楔叶纲(8.2%)和苏铁纲(4.1%)占一定比例,石松纲和种子蕨纲未见。与国内、外侏罗纪植物群或组合,特别是与我国北方中侏罗世11个研究较为系统的植物群进行了详细的对比和分析。结果表明,当前植物群明显具有中国北方Coniopteris-Phoenicopsis植物群早期组合的特点,其地质时代归为中侏罗世早期,大致相当于阿林期(Aalenian)至巴柔期(Bajocian)。华亭延安组化石植物以温暖湿润气候下繁盛的植物类型为主,兼具少数亚热带、热带气候下的植物成分,说明甘肃华亭地区中侏罗世为偏湿润的暖温带气候。
The macroscopic morphology and epidermal structure of plant fossils in Yan’an Formation of Huating, Gansu were analyzed. There were 49 genera and 24 genera in total. The composition of this flora is as follows: the proportion of true fern (28.6%), ginkgo (38.8%) is prosperous, coniferous ganglia (16.3%), wedge leaf ganglia (8.2%) and cycadida (4.1% Seed fern class did not see. It is compared and analyzed in detail with 11 domestic and overseas studies on the flora or assemblages of the Jurassic, especially the Middle Jurassic in North China. The results show that the current flora apparently has the characteristics of early assemblages of Coniopteris-Phenicopsis flora in northern China. The geologic age is classified as early Middle Jurassic, roughly equivalent to Aalenian to Bajocian. The fossil plants of Yan’an Formation in Huating are mainly of plant species that are prosperous in warm and humid climates, with the composition of plants in a few subtropical and tropical climates. It shows that the Middle Jurassic of Wuthering Heights in Tingting is a warm humid climate.