南海北部大陆架琼东南盆地西南部新近纪沟鞭藻类  

NEOGENE DINOFLAGELLATES FROM THE SOUTHWESTERN QIONG DONGNAN BASIN IN THE NORTH CONTINENTAL SHELF OF THE SOUTH CHINA SEA

作　　者：何承全[1] 祝幼华[1] 麦文 

机构地区：[1]中国科学院南京地质古生物研究所,南京210008 [2]中国海洋石油南海西部公司研究院,广东湛江524057

出　　处：《古生物学报》2005年第3期376-395,共20页Acta Palaeontologica Sinica

基　　金：国家自然科学基金(No.40372005)资助课题。

摘　　要：首次报道的低纬度晚第三纪(新近纪)丰富多样的海相沟鞭藻类,产自南海北部大陆架琼东南盆地西南部的两钻孔(主要是Ya2112井,少量为Ya2111井),经鉴定达40余种。文中仅对其中的31种4亚种进行了照相和对15种2亚种和1新种(Impletosphaeridiumcapillaresp.nov.)在我国进行了首次描述;在新近系建立2个沟鞭藻组合:即Hystrichosphaeropsisobscura组合(下部)和ReticulatosphaeraactinocoronataPolysphaeridiumzoharyi组合(上部),并讨论了它们的组合特征及其地质时代,认为其下部的组合时代为中新世,上部的组合时代为上新世。Rich and varied dinoflagellate cysts dealt with in this paper are obtained from the Neogene subsurface sediments of two offshore wells (mainly from well Ya21-1-2 with a depth of 1827.77-4562.79m, but a few from well Ya21-1-1 with a depth of 2413.98-3703.87m) drilled in the southwestern Qiong Dongnan(or Southeast) Basin, the North Continental Shelf of the South China Sea. More than fourty species belonging to 20 genera of dinoflagellates, Granodiscus granulatus of acritarchs, Pterospermella spp. of chlorophytes, and microforaminifer linings have been identified from well Ya21-1-2, of which 31 species of dinoflagellates are only illustrated and described in this work, including one new species, Impletosphaeridium capillare sp. nov. Two dinoflagellate assemblages have been recognized from the Neogene sediments of well Ya21-1-2 which are as follows in ascending order. 1. Hystrichosphaeropsis obscura Assemblage (at a depth of 3727.65-4562.79m) is marked by the latest occurrences of several species including Cordosphaeridium cantharellus, Bosedinia granulata, Hystrichosphaeropsis obscura and by the presence of Edwardsiella sexispinosa, Selenopemphix crenata and Impletosphaeridium capillare sp. nov. In the assemblage Hystrichokolpoma rigaudiae, H. denticulatum, Lingulodinium machaerophorum, Operculodinium centrocarpum, Polysphaeridium zoharyi, Selenopemphix nephroides, Spiniferites pseudofurcatus and S. ramosus subsp. ramosus are common; Nematosphae-ropsis labyrinthus, Tuberculodinium vancampoae and Stelladinium abei subsp. abei,etc. are rare or low in number. 2. Reticulatosphaera actinocoronata-Polysphae-ridium zoharyi Assemblage (at a depth of 1828.77-3727.65m) is characterized by: the high abundance and diversity,especially Polysphaeridium zoharyi having two times of high abundance in the assemblage, the absolute predominance of chorate cysts or gonyaulacaleans, lacking cavate cysts. Besides,"the highest occurrence"of Reticulatosphaera actinocoronata is interpreted herein as the base of this assemblage. Lingulodiniu

关 键 词：南海北部大陆架 琼东南盆地 沟鞭藻类 新近纪 西南部 晚第三纪 地质时代 组合特征 低纬度 NOV sp. 新近系 中新世 上新世 亚种 下部 新种 

分 类 号：Q914[天文地球—古生物学与地层学]