藏东吉塘地区冈瓦纳相冰海杂砾岩的特征及其意义

Glacial-marine diamictite of Gondwana facies in the Gyitang area, eastern Tibet, China, and its significance

察雅县吉塘镇澜沧江以西的酉西和泄巴发现冰海杂砾岩,是藏东地区班公湖-怒江缝合带以东首次发现的冈瓦纳相沉积岩,其基本特征与青藏高原南部的冈瓦纳相冰海杂砾岩相同,而吉塘镇澜沧江以东的石炭纪—二叠纪地层与古生物则是典型的扬子型的。冰海杂砾岩的分布范围大致代表冈瓦纳大陆塔尔切尔冰期影响的空间,并具有时代对比价值。这些资料可能说明一个事实,藏东地区石炭纪—二叠纪冈瓦纳大陆的东部边界为北澜沧江断裂带。

Glacio-marine diamictite, discovered in Youxi and Xieba west of the Lancang River, Gyitang Town, Zhag＇yab County, is Gondwana facies sedimentary rocks found for the first time east of the Bangong Co-Nujiang suture, eastern Tibet. Its basic feature is the same as those of the glacio-marine diamictite of Gondwana facies in the southern Qinghai-Tibet Plateau. The Carboniferous- Permian strata and fossils east of the Lancang River, Gyitang Town, are of typical Yangtze facies. Yangtze. The distribution of glaciomarine diamictite broadly represents the space affected by the Talchir glacier in Gondwana and may be used for age correlation. These data might suggest that the east boundary of Gondwana during the Carboniferous-Permian in eastern Tibet is the north Langcang River fault zone.