滇东南普阳盆地含煤地层孢粉组合特征及其年代  

Palynological assemblage and age of the Cenozoic coal-accumulation strata in the Puyang Basin,southeastern Yunnan Province

作　　者：杨久成 刘佳 李雨 苏涛[2,5] 李树峰 贾林波[6] 周浙昆 张世涛[1] Jiucheng Yang;Jia Liu;Yu Li;Tao Su;Shufeng Li;Linbo Jia;Zhekun Zhou;Shitao Zhang(Facultyof Land ResourceEngineering,KunmingUniversity of Scienceand Technology,Kunming 650093;CAS Key Laboratory of Tropical Forest Ecology,Xishuangbanna Tropical Botanical Garden,Chinese Academy of Sciences,Mengla,Yunnan 666303;State Key Laboratory of Palaeobiology and Stratigraphy(Nanjing Institute of Geology and Palaeontology,CAS),Nanjing 210008;ResearchCenterof Paleobiology,YuxiNormalUniversity,Yuxi,Yunnan 653100;Universityof ChineseAcademyof Sciences,Beijing 100049;CAS Key Laboratory for Plant Diversity and Biogeography of East Asia,Kunming Institute of Botany,Chinese Academy of Sciences,Kunming 650201)

机构地区：[1]昆明理工大学国土资源工程学院,昆明650093 [2]中国科学院西双版纳热带植物园热带森林生态学重点实验室,云南勐腊666303 [3]现代古生物学和地层学国家重点实验室(中国科学院南京地质古生物研究所),南京210008 [4]玉溪师范学院古生物研究中心,云南玉溪653100 [5]中国科学院大学,北京100049 [6]中国科学院昆明植物研究所,昆明650201

出　　处：《生物多样性》2022年第11期81-90,共10页Biodiversity Science

基　　金：国家自然科学基金(42002020,41922010);中国科学院南京地质古生物研究所现代古生物学和地层学国家重点实验室开放课题(193117);中国科学院西部之光青年学者项目(2020000023);云南省科技厅基础研究专项(202001AU070137)。

摘　　要：云南地处青藏高原东南缘,生物多样性丰富,季风气候特征明显。新生代剧烈的构造活动形成了众多山间盆地,其间保存了大量精美的植物化石,是探讨新生代以来植被、植物多样性和地球环境演变的理想地区。但是长期以来,由于地层年代学证据的缺乏,这些新生代沉积盆地的地质年代还存在很大争议。本研究通过对滇东南地区富宁县普阳盆地的含煤地层开展深入的孢粉学研究,探讨盆地含煤地层年代及其古气候演化过程。剖面下部煤层孢粉组合以杉粉属(Taxodiaceaepollenites)为主,指示以杉科为主的湿润沼泽森林,冬春季相对湿润;剖面上部孢粉组合指示以常绿栎类为主的亚热带常绿-落叶阔叶混交林,生长山核桃粉属(Caryapollenites)、冬青粉属(Ilexpollenites)、胡桃粉属(Juglanspollenites)、枫香粉属(Liquidambarpollenites)等亚热带常见树种,气候温暖湿润,季节分明。结合新发现的哺乳动物化石证据和周边地区不同地质时代的孢粉组合,普阳盆地含煤地层的沉积时代应为晚始新世;同时,孢粉组合也表明滇东南地区植被现代化面貌至少在晚始新世就已经开始出现。Aims:Located in the southeastern margin of the Tibetan Plateau,Yunnan Province is mainly characterized by a typical tropical monsoon climate and hosts the richest biodiversity in China.Dramatic tectonic activities during the Cenozoic era created many intermountain basins.These sedimentary basins provide excellent opportunities for understanding Cenozoic vegetation evolution,biodiversity and paleoenvironmental change.However,the ages of the basins remain far from fully investigated.Here we use the Puyang Coal mine section,Puyang Basin,southeastern Yunnan,southwestern China,to investigate paleoclimate and the evolution of vegetation,as well as the age of the coal-accumulation strata.Methods:In this study,40 palynological samples were collected from different layers in the Puyang Coal mine section,and the pollen and spores were extracted using the conventional acid-base method.The samples were used to reconstruct palynological assemblages and vegetation features by identifying and counting the species,quantity and proportion of pollen in sedimentary strata.Results:A total of 74 morphological genera of pollen were identified in this study,including 13 gymnosperms,49 angiosperms,10 ferns,and 2 algae.Conclusion:The palynological assemblage of the lower part of the study section is dominated by Taxodiaceaepollenites,indicating a swamp forest with a relatively humid climate in the cold season.The palynological assemblage of the upper section indicates a mixed subtropical evergreen and deciduous broadleaved forest,dominated by evergreen oaks,along with other subtropical taxa,such as Caryapollenites,Ilexpollenites,Juglanspollenites,and Liquidambarpollenites.It represents a warm and humid climate with significant seasonality.By combining newly discovered mammal fossil and palynological evidence,we infer that the age of the coal-accumulation strata in the Puyang Basin is late Eocene.The palynological assemblage also indicates the modernization of the biota in Southeast Yunnan since the late Eocene.

关 键 词：孢粉 普阳盆地 云南 晚始新世 生物多样性 

分 类 号：Q914.2[天文地球—古生物学与地层学]