西藏普兰县姜叶玛地区瓜德鲁普世晚期■类动物群及其古生物地理意义  

LATE MIDDLE PERMIAN(GUADALUPIAN)FUSULINE FAUNA FROM THE GYANYIMA AREA OF BURANG COUNTY,TIBET,CHINA AND ITS PALEOBIOGEOGRAPHIC IMPLICATIONS

作　　者：张以春[1] 

机构地区：[1]现代古生物学与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

出　　处：《古生物学报》2010年第2期231-250,共20页Acta Palaeontologica Sinica

基　　金：中国科学院重点方向项目(KZCX2-YW-122);中国科学技术部973项目(2006CB806400);自然科学基金(40473003);中国科学院南京地质古生物研究所现代古生物学与地层学国家重点实验室基金(093105);国家基础科学人才培养基金(No.J0630967)资助

摘　　要：雅鲁藏布江缝合带中自西向东分布着二叠纪灰岩块体,被称为西藏相灰岩外来块体或奇底宗型的二叠系。姜叶玛灰岩是其中之一,位于西藏西部普兰县境内。■类动物群是该灰岩块体中最丰富的生物群之一,其中瓜德鲁普统西兰塔组的■类有10个属,分别为Neoschwagerina,Yangchienia,Armenina,Verbeekina,Paraver-beekina,Kahlerina,Lantschichites,Codonofusiella,Chusenella,Nankinella。Kahlerina,Lantschichites和Codono-fusiella的存在表明西兰塔组■类动物群的时代为Midian期(Guadalupian世晚期),相当于华南的冷坞期。姜叶玛灰岩和仲巴县拉赛拉灰岩、阿曼Batain地区以及巴基斯坦盐岭地区一样,Midian期■类动物群缺少Afghanella-Sumatrina组合,结合当时古地理位置认为,这几个地区处于相对较凉水温控制之中。Numerous Permian limestone blocks exposed along the Yarlung-Zangbo Suture Zone have been named Tibetan facies exotic limestone blocks or Chitichun-type Permian deposits.The Gyanyima limestone block,one of those limestone blocks,is located in Burang County,southwestern Tibet.Fusulines are abundant in the Gyanyima limestone block especially for Middle Permian Xilanta Formation.The fusuline fauna comprises 10 genera,respectively Neoschwagerina,Yangchienia,Armenina,Verbeekina,Paraverbeekina,Kahlerina,Lan-tschichites,Codonofusiella,Chusenella and Nankinella.This fauna indicates a Midian age（Late Guadalupian or Lengwuan age of South China）in terms of the coexistence of Kahlerina,Lan-tschichites,Codonofusiella and Neoschwagerina.Paleobiogeographically,the fauna closely resembles that from the Lasaila exotic limestone block of Tibet,the Batain plain of Oman and the Salt Range of Pakistan,which are all characterized by absence of Afghanella-Sumatrina assemblage in the fauna,suggesting that the Gyanyima limestone block,the Lasaila limestone block,the Batain plain of Oman and the Salt Range of Pakistan,were affected by relatively cool water currents during the Middle Permian.

关 键 词：类 古生物地理 瓜德鲁普世 西藏 

分 类 号：Q915[天文地球—古生物学与地层学]