摘要
基于近十几年以来青藏高原东北缘活动构造运动特征调查与定量研究结果，在总结区域活动构造运动特征基础上，指出青藏高原东北缘发育有近东西-北东东向的大型左旋走滑断裂带（祁连-海原断裂、阿尔金断裂等）、北西西向的逆冲断裂带（祁连山内部及边缘断裂、河西走廊内部及边缘断裂和六盘山断裂等）和北北西向的右旋走滑断裂带（主要是鄂拉山断裂与拉脊山断裂）3组不同方向以及不同运动性质的活动断裂，它们共同控制着青藏高原东北缘的活动构造几何图像和运动转换；其中，大型左旋走滑断裂在区域构造运动转换过程中起着控制性作用，逆冲断裂一般发育在大型走滑断裂的端部，起着调节和吸收大型走滑断裂端部水平滑动的作用，而祁连山南部右旋走滑断裂主要是对不同块体差异运动过程进行调节。结合区域新构造变形的研究结果，认为青藏高原东北缘不同方向和性质活动构造的发育、形成、生长以及扩展过程，控制着高原东北缘构造变形和演化的历史；高原东北缘由南向北逐渐扩展，逐步形成了青藏高原东北缘的现今构造格架，而高原东北缘新活动边界在新生代晚期已越过河西走廊到达阿拉善地块南缘，同时在东北缘弧形构造带的位置也已形成了以三关口-牛首山断裂带为主的高原隆升和向外扩展的新边界。
Available studies suggested that the northeastern Tibetan Plateau is the growing and expanding frontier following the India-Eurasia collision. Cenozoic deformation due to the continuous India-Eurasia collision has been the driver for the landscape evolution of the NE Tibetan Plateau. During recent decades, both the international and domestic efforts on large-scale active fault mapping collected plenty of basic information and data to understand the deformation pattern. Numerous results from studies related to active faults and folds, Cenozoic basin sediments and geodesy observations help our new insights into the geological history of this growing plateau. The Late Quaternary geometry and kinematics of the northeastern Tibetan Plateau are characterized by three groups of active faults of different strikes： the EW-NEE trending left-lateral strike-slip faults, NWW striking thrust faults and NNW trending right-lateral strike-slip faults. Among of them, the dominated left-lateral strike-slip faults are major structures in transferring deformation in this region; the thrusts are mainly developed at the tips of the strike-slip faults, absorbing and dissipating the lateral strike slip rate along the boundary strike-slip fault; the right-lateral strike-slip faults developed in southern Qilian Shan mainly accommodated the relative motion between active blocks. These three groups of active faults indicate the outward and growth process of the Tibetan Plateau. The Qilian-Haiyuan Fault and Altyn-Tagh Fault both contribute to the adjustment and transformation of the strain, and indicate a continuous deformation pattern of the NE Tibetan Plateau. Deformation near the ends of these two faults were being absorbed by the thrust and shortening within the Qilian Shan and Liupan Shan, respectively. In the northeastern margin, the Tibetan Plateau was observed to be progressively growing following the uplift of the Qilian Shan from south to north. The deformation has extended into the southern margin of the Gobi Alashan block across the Hexi Corridor in Late Cenozoic. In the northeastern margin, the Sanguankou-Niushoushan Fault zone located to the northeast of the Haiyuan Fault, is the youngest boundary between the Tibetan Plateau and the Ordos block, indicating that the deformation has extended from the Haiyuan Fault to the further northeastern direction progressively.
出处
《第四纪研究》
CAS
CSCD
北大核心
2016年第4期775-788,共14页
Quaternary Sciences
基金
中国科学院战略性先导科技专项项目（批准号：XDB03020200）、国家自然科学基金项目（批准号：41590861、41372220、41172194和41661134011）和中国地震局地质研究所基本科研业务费专项项目（批准号：IGCEA1220）共同资助致谢本文是在前人大量研究基础上一个总结,在此对致力于青藏高原研究的各位前辈、同仁表达最崇高的敬意和深切的谢意
匿名审稿人对论文的修改和完善提出了建设性意见,在此真挚地表示感谢!致谢本文是在前人大量研究基础上一个总结,在此对致力于青藏高原研究的各位前辈、同仁表达最崇高的敬意和深切的谢意
匿名审稿人对论文的修改和完善提出了建设性意见,在此真挚地表示感谢!
关键词
活动构造
几何图像
运动转换
高原扩展
青藏高原东北缘
active tectonics, geometry, kinematics, outward and growth of the plateau, the northeasternmargin of the Tibetan Plateau
