【摘要】 豫西宜阳上二叠统孙家沟组为一套陆相碎屑岩,在该组中部土门段砂泥互层中发现大量的植物化石碎片和孢粉化石。文中依据孙家沟组沉积特征及孢粉组合区域对比,厘定了土门段的地质时代,并依据孢粉化石的亲缘植物关系和信息函数,结合微量元素Sr/Cu值指标,定性和半定量分析了宜阳地区的古气候特征。结果显示:土门段共发现52属孢粉化石,以裸子植物花粉占优势,与华北地区晚二叠世孢粉组合特征有很大的相似性,推测其地质时代相当于晚二叠世长兴期。孢粉化石属种的植物亲缘关系与欧美镁灰岩统植物成分类似,表明整体上为较炎热的半干旱古气候。该成果可为华北地区晚二叠世晚期的陆相沉积环境、古植物背景以及古气候演化研究提供参考依据。更多还原

【Abstract】 A set of continental clastic rocks developed in the Upper Permian Sunjiagou Formation in Yiyang area,western Henan Province. A large number of plant fossils and sporopollen fossils are preserved in the interbedded sandstone and mudstone of the middle member( the Tumen Member) of the Sunjiagou Formation. Based on the sedimentary characteristics and the regional stratigraphic correlation of Sporopollen assemblage,the geological age of the Tumen Member is determined. Furthermore,according to the relationship of sporopollen fossils and their information function,combined with the value of trace element Sr/Cu,the palaeoclimatic environment of the Yiyang area is qualitatively and semi-quantitatively analyzed.A total of 52 genera of sporopollen fossils were found,with gymnosperm pollen dominant,which are similar to the characteristics of the Late Permian sporopollen assemblage in North China. It is inferred that the Tumen Member of Sunjiagou Formation in the Dayulin section belongs to the Changxing Age of the Late Permian. The above results may provide a reference for the study of continental sedimentary environment,palaeobotanical background and palaeoclimate evolution in the Late Permian of North China.更多还原