西藏南部白垩纪岗巴群的双壳类及其生物地理意义(英文)  

CRETACEOUS BIVALVES OF KANGPA GROUP,SOUTH XIZANG, CHINA AND THEIR BIOGEOGRAPHY

作　　者：文世宣[1] 

机构地区：[1]中国科学院南京地质古生物研究所,南京210008

出　　处：《古生物学报》2000年第1期1-27,共27页Acta Palaeontologica Sinica

基　　金：国家重点基础研究专项经费资助;中国科学院青藏高原研究项目!(KZ95 1 Al 2 0 4,KZ95T 0 6)成果

摘　　要：描述双壳类化石 42种 ,建立 1 0新种 :Grammatodon (Nanonavis)minumsp .nov.,Propeamussium(P .)tibetensesp.nov.,Plicatulahimalayensissp.nov.,Pseudolimeaduodecicostatasp .nov.,Pycnodonte (Phygraea)gambaensissp.nov.,Nototrigonia (N .)himalayensissp.nov.,Linearia (L .) gieumalensissp.nov.,Icanotiaxizan gensissp.nov.,Panopeaxizangensissp.nov.,Cuspidariatibiticasp.nov.。它们均产自西藏南部岗巴地区的岗巴群。其中大部分标本产自岗巴群的下中部 ,时代为Aptian至Albian期 ,少量产自岗巴群上部 ,时代大致为Cenomanian至Coniacian期。Aptian—Albian期双壳类有地区性属Astartoides和Yoldioides以及众多地区性种 (约占 6 1 % ) ,标志着一个地区性中心的存在。同时 ,它们又表现出与澳大利亚Aptian—Albian动物群有密切的联系 ,澳大利亚特有的属Eyrena,Maccoyella,Nototrigonia和特有的种 (约占 2 9% )在岗巴群下中部被找到 ,都是在北半球的首次记录。这个动物群与雅鲁藏布江缝合带以北同时期的动物群差别很明显 ,后者与东亚、西亚和欧洲的双壳类有密切的联系。这些事实说明 ,在Aptian—Albian时期 ,印度次大陆已经开始向北漂移 ,但漂移的距离还不远 ,位于印度次大陆北部边缘浅海的岗巴?In this paper 42 bivalve taxa including 10 new species recovered from the Kangpa Group of South Xizang (Tibet) are described. Most of them come from the middle and lower parts of the group which is Aptian-Albian in age, and the others from the upper part belonging to Cenomanian-Coniacian in age. The fauna of the middle and lower parts bearing endemic genera Astartoides and Yoldioides and numerous endemic species (about 619% ), marks the existence of an endemic centre. It is distinctly different from that of the area on the north of the Yarlung Zangbo River Suture Zone which shows close relation with that of East Asia, West Asia and Europe. In the meantime, some of Australian characteristic genera, such as Eyrena, Maccoyella and Nototrigonia, and a number of such species ( about 29 % ) are found from the middle and lower parts of the Kangpa Group,which are recorded in Northern Hemisphere for the first time. This fact indicates that the Indian Subcontinent had already started its drifting northward, but the drift distance should be not far from Antarctica-Australia in Aptian-Albian, with the fauna of the Kangpa Group living in the north epicontinental sea of the subcontinent still could maintain the relation and exchange with that of Australian bivalves in spite of the fauna with a strong local colour.

关 键 词：双壳类 古生物地理 白垩纪 藏南 岗巴群 动物群 

分 类 号：Q915[天文地球—古生物学与地层学]