摘要
柴达木盆地发育了一套完整的古近纪—新近纪河湖相沉积地层,选择在其北缘大红沟剖面采集沉积物样品进行孢粉鉴定分析。根据孢粉组合特征划分出14个孢粉组合带,揭示了该地区古近纪到新近纪的植被、气候变化历史。结果显示:该地区古近纪—新近纪植被代表一种北亚热带常绿阔叶林→暖温带、温带落叶阔叶针叶林→温带针阔叶混交林→山体针叶林→干旱草原荒漠的植被生态景观演变过程。通过对柴达木盆地大红沟剖面植被面貌分析,推断古近纪—新近纪期间研究区气候存在多次冷暖干湿变化,呈现出由暖湿向冷干发展的趋势。11~9 Ma低温干燥的特征与中新世中期全球气候适宜期趋势不一致,可能是盆地构造运动导致的区域特殊性。
Pollen samples were obtained from the northern margin of Qaidam Basin,where Paleocene to Pliocene lacustrine-facies sequences are exposed.Fourteen palynological assemblages have been identified by pollen identification and analysis,which shed light on the vegetation and climate change history of the basin.The pollen analysis results have recognized the Eocene Climatic Optimum,and revealed a vegetation evolution of northern subtropical ever green broad leaf forest→warm,temperate deciduous broad-leaved coniferous forest→temperate mixed forest→coniferous forest→arid mountain desert.The paleoclimate can be inferred from the vegetation correlation with the global climate trends,which matches the global climatic events.Cold to warm and dry to humid fluctuations can also be distinguished on the basis of the palynofloras recovered from the basin.A cold and dry period during 11-9 Ma,different from the Middle Miocene Climatic Optimum(MMCO),may have been caused by tectonic movements in the Qaidam Basin.
作者
路晶芳
张克信
宋博文
徐亚东
张楗钰
黄威
张道来
LU Jingfang;ZHANG Kexin;SONG Bowen;XU Yadong;ZHANG Jianyu;HUANG Wei;ZHANG Daolai(Qingdao Institute of Marine Geology,China Geological Survey,Qingdao,Shandong 266071,China;Laboratory for Marine Mineral Resources,Qingdao National Laboratory for Marine Science and Technology,Qingdao,Shandong 266071,China;Institute of Geological Survey,China University of Geosciences,Wuhan,Hubei 430074,China;School of Earth Sciences,China University of Geosciences,Wuhan,Hubei430074,China;Wuhan Center,China Geological Survey,Wuhan,Hubei 430205,China)
出处
《现代地质》
CAS
CSCD
北大核心
2020年第4期732-744,共13页
Geoscience
基金
国家自然科学基金青年基金项目(41406079)
自然资源部海洋油气资源与环境地质重点实验室开放基金项目(MRE201412)
中国地质调查局地质调查项目(DD20190578)。
