青藏高原北部白垩纪隆升的证据  

Evidence for Cretaceous uplift of the northern Qinghai-Tibetan plateau

作　　者：李海兵[1] 杨经绥[1] 

机构地区：[1]国土资源部大陆动力学重点实验室

出　　处：《地学前缘》2004年第4期345-359,共15页Earth Science Frontiers

基　　金：国家重点基础研究发展规划项目(973)青藏高原项目(G1988040800);国家自然科学基金资助项目(40272096)和地质调查项目(200313000058);科学技术部重大基础研究前期研究专项(2002CCA05100)

摘　　要：认为青藏形成统一大陆应该在印支期晚期古特提斯洋关闭和海水退出时。由于来自冈瓦纳大陆的羌塘微陆块向NE斜向俯冲 ,产生了印支期的阿尼玛卿、柴北缘和阿尔金大规模走滑断裂的形成 ,并且由于东部受到华南板块的阻挡 ,形成南北向的龙门山褶皱带。此阶段 ,地势较低 ,海拔不高。直至中特提斯洋在白垩纪早期关闭 ,来自冈瓦纳大陆的冈底斯微陆块沿班公湖—怒江一线俯冲到北部高原的下面 ,由于高原北部受到塔里木—阿拉善地块的阻挡 ,东部受到南中国板块的阻挡 ,高原北部开始隆升 ,形成高原雏形。高原南北统一大陆形成于新特提斯洋的关闭和印度板块沿雅鲁藏布江缝合带与欧亚大陆碰撞时 ,并在新近纪后开始快速抬升 ,形成现今的高原地貌 ,这已是共识。值得讨论的是 ,如何识别高原北部白垩纪时期的隆升 ,以及其对建立高原隆升模型和计算高原北部隆升速率的贡献。The northern Qinghai-Tibet Plateau became a coherent block after closure of the Paleo-Tethys Ocean in the Triassic. During the closure, a series of major strike slip faults,such as the Altyn Tagh, Anemaqen and North Qaidam faults were formed as a result of the NE-directed oblique subduction of the Qiangtan block, which had previously separated from the Gondwanaland. The N-S Longmenshan fold belt was also formed at that time due to the buttressing effect of the South China Plate to the east. Uplift of the northern Qinghai-Tibet plateau began in the Cretaceous as a result of closure of the Middle Tethys Ocean and subduction of the Gangdes Block beneath north Tibet along the Bankong Lake-Nujiang river suture zone. Uplift of the plateau was aided by the buttressing effect of the Tarim-Alax platform to the north and by the westward subduction of the Pacific Plate beneath the China Continent.

关 键 词：阿尔金断裂 特提斯 冈瓦纳 隆升 青藏高原 

分 类 号：P54[天文地球—构造地质学]