拉萨地块叶巴组内中侏罗世双壳类动物群及其古地理意义  

THE MIDDLE JURASSIC BIVALVE FAUNA IN THE VOLCANIC ROCK SERIES(YAIBA FORMATION)OF THE LHASA MASSIF AND ITS PALEOGEOGRAPHIC SIGNIFICANCE

作　　者：阴家润[1,2] 苟金 裴树文 蒋光武 

机构地区：[1]中国地质大学地矿系 [2]青海地勘局区调大队 [3]西藏地矿厅区调队

出　　处：《中国区域地质》1998年第2期132-136,共5页Regional Geology of China

基　　金：国家自然科学基金

摘　　要：位于拉萨地块南缘的叶巴组内首次采集到丰富的双壳类化石，共计有１４个种和未定种。表明叶巴组的火山活动发生在中侏罗世巴柔期，中侏罗早期是新特提斯（ＮｅｏＴｅｔｈｙｓ）洋盆形成的重要阶段。拉萨地块上所发现的海相双壳类动物群具有东、西特提斯生物地理分区的典型分子，表明在此期间所谓的“班公湖—怒江海”未构成对拉萨地块和羌塘地块之间动物群互相沟通的地理障碍。Abundant bivalve fossils were first collected from a volcanic rock series(Yaiba Formation)on the southern margin of the Lhasa massif.They include 14 species and indeterminate species.This indicates that volcanism in the Yaiba Formation took place in the Middle Jurassic Bajocian Stage and proves that the early Middle Jurassic was an important stage in the formation of the Neo Tethys ocean basin.The marine bivalve fauna discovered in the Lhasa massif contains typical elements of the East and West Tethys biogeographic provinces.The authors hold that the “Bangong Co Nujiang Sea”did not constitute a geographic barrier to the ocean basin nature of the area between the Lhasa massif and the Qiangtang massif for the interchange of faunas.

关 键 词：拉萨地块 中侏罗世 双壳类 古生物地理 动物群 

分 类 号：Q915.652[天文地球—古生物学与地层学]