新疆准噶尔南缘和吐鲁番盆地二叠─三叠系

路线考察新疆吉木萨尔大龙口和吐鲁番盆地两条剖面。剖面层序清楚、出露良好、化石丰富，是研究非海相二曾─三叠系界线的理想地点。吉木萨尔大龙口剖面由上二叠统和完整的三叠系组成大龙口背斜，其北翼地层发育齐全，南翼可观察到世界罕见的二叠─三叠纪生物与沉积过渡层，两系之间孢粉、介形虫、叶肢介、脊椎动物各门类化石丰富，其中晚二叠世晚期新疆吉本萨尔兽与世界公认的早三叠世标准化石水龙兽共生，目前该剖面已推荐为国际非海相二叠─三叠系界线层型候选剖面。吐鲁番盆地是世界著名的地处海平面之下地区，该区桃树园剖面发育完整、出露良好，特点是脊椎动物化石丰富．上二叠统桃东沟群不整合超覆在石炭系火山岩之上，其上，与上二叠统一下三叠统仓房沟群和中一上三叠统连续沉积，侏罗系含煤层整合在三叠系之上．

THE PERMIAN-TRIASSIC SEQUENCES IN THE SOUTHERN MARGIN OF THE JUNGGAR BASIN AND THE TURPAN BASIN,XINJIANG

This trip will examine the Dalongkou section in Jimsar and the Taoshuyuan section in Turpan,Xinjiang,in which the nonmarine Permian-Triassic sequences are well-developed with abundant fossils. At thesouthern limb of the Delongkou anticline,the continuous Permian-Triassic transitional deposits containingvery rich sporo-pollen, ostracods, conchostracans, veterbrates of Jimsaria of Late Permian and Lystrosaurus ofEarly Triassic can be examined. The Dalongkou section has been recommended as one of the candidate sectionof the nonmarine P-T boundary stratotype. In the Turpan Basin the Upper Permian,the Triassic and the overlying Jurassic coal-measures can be observed in the Taoshuyuan section.