重庆合川地区晚三叠世须家河组孢粉组合  

LATE TRIASSIC SPORE-POLLEN ASSEMBLAGE FROM THE XUJIAHE FORMATION IN HECHUAN OF CHONGQING,CHINA

作　　者：刘兆生[1] 李丽琴[1,2] 王永栋[1,3] 

机构地区：[1]中国科学院南京地质古生物研究所,南京210008 [2]中国科学院大学,北京100049 [3]中国科学院资源地层学与古地理学重点实验室,南京210008

出　　处：《古生物学报》2015年第3期279-304,共26页Acta Palaeontologica Sinica

基　　金：国家重点基础研究发展计划(973)项目(2012CB822003);中国科学院知识创新重要方向性项目(KZCX-2-YW-154);国家自然科学基金项目(41272010);中国科学院科技创新交叉与合作团队项目;中国科学院南京地质古生物研究所一三五重点学科部署项目联合资助

摘　　要：四川盆地南部重庆合川炭坝剖面须家河组中发现丰富的孢粉化石,共计73属150种,其中包括蕨类植物孢子41属89种,裸子植物花粉29属56种,苔藓植物孢子1属3种,藻类化石2属2种。建立一个孢粉组合,命名为Dictyophyllidites-Lunzisporites-Chasmatosporites组合(简称DLC组合),并进一步分为下亚组合和上亚组合。根据孢粉组合内一些重要分子的地质时代延限及与国内外有关孢粉组合的对比,确定其地质时代为晚三叠世晚期,相当于诺利期—瑞替期(Norian—Rhaetian),并且倾向于瑞替期(Rhaetian)。Spore-pollen assemblage, Xujiahe Formation, Late Triassic, Sichuan Basin, Hechuan, Chongqing 2） Gymnospermous pollen grains are abundant and up to 37. 0% in the assemblage, represented by bisaccate conifer pollen grains （16.8%） , including Pinuspollenites divulgatus , P. globosaccus, P. alatiopollenites, P. elongatus, P. minutus, P. rectus, Quadraeculina anellaeforrnis, Q. minor, Q. canadensis, Q. ordinata, Q. enigmata, Pseudopicea variabili formis , P. rotundi formis, Pseudopinus pectinella and P. cavernosa, etc. The monosulcate pollen grains （14. 8%） are the second abundant group among gymnosperm pollen taxa, comprising Cycadopites reticulata , C. mag nus, C. minor, Chasmatosporites apertus, C. hians, C. major, C. elegans, C. minor. Asaccate pollen grains rank the third in abundance （4.3%）, including Psophosphaera minor （ 3. 3 %）, Classopollis annulatus, C. parvus, Ricciisporites tuberculatus and R. cf. tenuis. The striate, ridged and laesurate bisaccate pollen are rare （0.8%）, in cluding Taeniaesporites albertae , Parataeniaesporites pseudostriatus , Limitisporites sp. , and Chordasporites australiensis. The rest of gymnosperm pollen grains are rare, including Cordaitina and Florinites, Callialasporites dampieri, Cerebropollenites mesozoicus , C. carlylensis, Perinop ollenites elatoides, Ovalipollis ovalis and O. brewi f ormis. 3） Additionally, 2 species referred to 2 genera of algal fossil and 3 species referred to 1 genus of bryophyte spores are recorded in this assemblage. The present spore-pollen assemblage is assigned to late Irate Triassic in geological age based on stratigraphic distribution analyses of important taxa, such as Kyrtomisporis, Habrozonosporites, Aratrisporites, Taeniaesporites, Ovalipollis, Ricciisporites, Dictyophyllidites, Lunzisporites, Chasmatosporites, etc. The DLC assemblage shows similarities to the coeval sporo-pollen assemblages previously reported from the neighboring regions of the Sichuan Basin, the Shezi Formation of Yunnan, the Anyuan and Sanqiutian

关 键 词：孢粉组合 须家河组 晚三叠世 四川盆地 合川 重庆 

分 类 号：Q914[天文地球—古生物学与地层学]