摘要
描述了发现于鄂西香溪组的两种植物化石CtenozamitessarraniZeiller和Eboracialobifolia(Phillips)。香溪组下部Toditesprinjceps Czekanowskia植物组合和上部Coniopterismurrayana Ptilophyllum植物组合虽都以真蕨类Coniopteris和双扇蕨科植物为特色 ,但下组合银杏类很多 ,苏铁类却较少 ,而上组合苏铁类则很发达 ,尤其是Otozamiteshsiangchiensis ,O mixomorphus,Ptilo phyllumcontiguum等未在下组合中出现 ,银杏类亦相对较少 ,上、下植物组合的这种差异明显与当时的气候环境有关。同时 ,依据上组合含Ctenozamitessarrani和Thaumatopteris等分子和它们尚未在中侏罗世发现 ,提出香溪组上部的时代为早侏罗世晚期。
Two species of plant fossils,Ctenzamites sarrani Zeiller and Eboracia lobifolia (Phillips) found from the Upper Xiangxi Formation in Zigui County of Hubei Province,are described. Although the Todites princeps-Czekanowskia assemblage and the Coniopteris murrayana-Ptilophyllum assemblage outcroped separately in the lower and upper part of the Xiangxi Formation are characterized by the occurring of Coniopteris and Dipteridaceae,more Ginkgophytes and less Cycadophytes are found in the lower assemblage with Otozamites hsiangchiensis,O.mixomorphus and Ptilophyllum contiguum disappeared, While more Cycadophytes and less Ginkgophytes are present in the upper assemblge,the species difference might be resulted from different climate conditions.According to Ctenozamites sarrani and Thaumatopteris occur in the upper assemblage and have be found in the Middle Jurassic strata,the Upper Xiangxi Formation is suggested to be late Early Jurassic in age.
出处
《华南地质与矿产》
CAS
2002年第4期35-40,共6页
Geology and Mineral Resources of South China
基金
中国地质调查局"中国古大陆环境变化及其年代
生物
层序
事件
化学和构造地层响应"项目 ( 2 0 0 11390 0 0 72 )
关键词
早侏罗世
植物化石
香溪组
湖北
气候环境
Early Jurassic
plant fossil
Xiangxi Formation
western Hubei