Cenozoic exhumation in the Qilian Shan, northeastern Tibetan Plateau: Evidence from detrital fission track thermochronology in the Jiuquan Basin
Cenozoic exhumation in the Qilian Shan, northeastern Tibetan Plateau: Evidence from detrital fission track thermochronology in the Jiuquan Basin
复制标题
DOI：
10.1002/2017jb014216
复制
发表时间：
2017-08
期刊：
影响因子：
--
通讯作者：
Pengju He;Chunhui Song;Yadong Wang;Lihao Chen;P. Chang;Qiangqiang Wang;Bo Ren
中科院分区：
文献类型：
--
作者：
Pengju He;Chunhui Song;Yadong Wang;Lihao Chen;P. Chang;Qiangqiang Wang;Bo Ren
印度-亚洲碰撞形成了新生代断裂、山脉和构造盆地的格架，以及青藏高原东北部的高地貌，但这些特征是如何以及何时形成的仍然知之甚少，导致了相互冲突的构造模式。然而，这些活动造山带的构造演化信息在同造山盆地沉积中保存得很好。本研究通过对酒泉盆地新生代同造山沉积的碎屑磷灰石裂变径迹年龄的分析，揭示了邻近祁连山新生代的整个折返过程。我们的资料表明，祁连山在古新世晚期-始新世早期(~60-50 Ma)发生了最初的快速新生代折返，与印度-亚洲碰撞几乎同步。祁连山随后经历了漫长的折返过程，至少持续到中新世中期(~45-10 Ma)。在祁连山折返期间，整个青藏高原东北部都发生了构造变形。青藏高原东北部新生代早期的变形可能是构造应力通过青藏高原复杂的岩石圈环境从遥远的印度-亚洲碰撞边界转移而来的。祁连山和青藏高原东北部现今的构造形态和地貌可能是在中新世中期和早新生代开始长期变形之后形成的。
The India‐Asia collision resulted in the Cenozoic framework of faults, ranges, and tectonic basins and the high topography of the northeastern Tibetan Plateau, but how and when these features formed remains poorly understood, leading to conflicting tectonic models. However, information on the tectonic evolution of these active orogenic belts is well preserved in synorogenic basin sediments. In this study, we carefully analyze the detrital apatite fission track ages of Cenozoic synorogenic sediments from the Jiuquan Basin to decipher the entire exhumation process of the adjacent Qilian Shan throughout the Cenozoic. Our data indicate that initially rapid Cenozoic exhumation occurred in the Qilian Shan during the late Paleocene‐early Eocene (~60–50 Ma), almost synchronous with the India‐Asia collision. The Qilian Shan subsequently experienced long‐lived exhumation that continued until at least the middle Miocene (~45–10 Ma). During this period of exhumation in the Qilian Shan, tectonic deformation occurred throughout the northeastern Tibetan Plateau. The early Cenozoic deformation in the northeastern Tibetan Plateau may have been caused by the transfer of tectonic stress from the distant India‐Asia collision boundary through the complex lithospheric environment of the Tibetan Plateau. The present tectonic configuration and topography of the Qilian Shan and the northeastern Tibetan Plateau likely became established since the middle Miocene and after the long‐lived deformation began in the early Cenozoic.