西藏申扎县木纠错地区晚三叠世多布日组的发现及其地质意义

The discovery of the late Triassic Duoburi Formation in the Mujiucuo area,Shenzha County,Tibet and its geological significance

吉林地质调查院在开展西藏自治区1∶25万多巴区幅区域地质调查时,在木纠错西的申扎县多布日一带发现一套陆相—海陆交互相—滨浅海相地层,并采集到了珊瑚化石、海参化石、植物化石、介形类化石、腹足化石、藻类化石和孢粉化石等。根据这些古生物化石确定该套地层为晚三叠世沉积。从而首次证明了冈底斯—腾冲区永珠蛇绿岩带以南存在晚三叠世地层。这一发现为我国三叠系的划分对比提供了重要的依据,并为古特提斯海的演化历史,古地理轮廓的确定以及青藏高原的形成演变历史提供了新的资料。

In the regional investigation (1∶250 000) in the Duoba,Tibet autonomous region,a series of strata of the continental-marine alternation were discovered in the Duoburi area,Shenzha,western part of Mujiucuo,and some coral,sea cucumber,plant,alga and sporopollen fossils were collected The fossils show that the strata belong to the late Triassic sedimentation,thus it is certified for the first time that the south of Yongzhu ophiolite zone,Gandise- Tengcong area occurred in the late Triassic strata It provides an important base for the stratigraphic correlation of the Triassic in China,and the new data for the evolutionary process of the PaleoTethys Sea,and the determination of the paleogeographic outline as well as the forming evolution of the Qinghai-Tibet plateau.