Neogene palynological assemblages in the west slope of Songliao Basin and their geological implications  

作　　者：WAN ChuanBiao SUN YueWu XUE YunFei QIAO XiuYun JIN YuDong ZHANG YiYong 

机构地区：[1]Exploration and Development Research Institute of Daqing Oilfield Company Ltd. [2]Research Center of Paleontology and Stratigraphy, Jilin University [3]Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences

出　　处：《Science China Earth Sciences》2014年第10期2486-2497,共12页中国科学（地球科学英文版）

基　　金：financially supported by the National Basic Research Program of China(Grant No.2006CB701401);the National Natural Science Foundation of China(Grant No.31270277)

摘　　要：Abundant palynological fossils are found from the drill core in the west slope of Songliao Basin, the first full coring borehole that drilled throughout the Neogene. Two Palynological assemblages are recognized according to their vertical distributions, i.e., the late early Miocene-middle Miocene assemblage from the Da＇an Formation named as Caryapollenites sim- plex-Momipites coryloides-Celtispollenites sp.-TsugaepoUenites igniculus, and the late Miocene-early Pliocene assemblage from the Taikang Formation named as Artemisiaepollenites minor-BetulaceoipoUenites sp.-Carpinipites sp.-Polypodiaceae- sporites sp. On the basis of the composition of each assemblage, we infer that the climate was warm-temperate to sub-tropic during the late early Miocene-middle Miocene and the vegetation was mainly deciduous broadleaved forest and subordinate coniferous and broad-leaved mixed forest with few understory ferns, and probably some shallow fresh water wetlands. The climate then turned cooler and drier in the late Miocene-early Pliocene, represented by the development of xerophytic herbs and temperate plants, although the canopy of the forest remained relatively stable. The results significantly improve the under- standing of the Cenozoic palynostratigraphy in the Songliao Basin, and provide new data for both stratigraphical correlation and paleovegetational and paleoclimatical analysis in adjacent area.Abundant palynological fossils are found from the drill core in the west slope of Songliao Basin, the first full coring borehole that drilled throughout the Neogene. Two Palynological assemblages are recognized according to their vertical distributions, i.e., the late early Miocene–middle Miocene assemblage from the Da'an Formation named as Caryapollenites simplex-Momipites coryloides-Celtispollenites sp.-Tsugaepollenites igniculus, and the late Miocene-early Pliocene assemblage from the Taikang Formation named as Artemisiaepollenites minor-Betulaceoipollenites sp.-Carpinipites sp.-Polypodiaceaesporites sp. On the basis of the composition of each assemblage, we infer that the climate was warm-temperate to sub-tropic during the late early Miocene–middle Miocene and the vegetation was mainly deciduous broadleaved forest and subordinate coniferous and broad-leaved mixed forest with few understory ferns, and probably some shallow fresh water wetlands. The climate then turned cooler and drier in the late Miocene–early Pliocene, represented by the development of xerophytic herbs and temperate plants, although the canopy of the forest remained relatively stable. The results significantly improve the understanding of the Cenozoic palynostratigraphy in the Songliao Basin, and provide new data for both stratigraphical correlation and paleovegetational and paleoclimatical analysis in adjacent area.

关 键 词：western Songliao Basin MIOCENE PLIOCENE pollen and spores ALGAE PALEOCLIMATE 

分 类 号：P534[天文地球—古生物学与地层学] Q914[天文地球—地质学]