中国大陆中轴构造带地壳最新构造变动样式及其动力学内涵

MODEL OF LATEST CRUSTAL TECTONIC MOTION OF THE CENTRAL TECTONIC ZONE ON THE MAINLAND OF CHINA

文中通过对已有地质调查和地球物理探测成果的系统分析与综合 ,给出了中轴构造带地表活动构造的分段特征 ,特别是近地表显示地壳缩短变形的挤压构造特征 ;初步论证了中轴构造带中南段为岩石圈深度范围阻挡青藏高原物质东向或南东向滑移的阻挡构造边界 ,且具有上、下呼应的深浅构造关系 ;指出中轴构造带内部活动挤压构造具有把青藏高原北西向左旋走滑控制的块体东向或南东向滑移转换成为隆升运动的构造转换作用 ;对其中南段整体的综合研究有助于深刻理解中国大陆最新构造变动和地震时空迁移的动力学问题。

From systematic analysis and synthesis of geological surveying and geophysical exploring data, it is known that the central tectonic zone on the mainland of China is characterized by segmentation of active tectonics and various active crustal shortening structures. It is also demonstrated that its middle and southern segments are obstructing structural boundaries that consist of shallow and deep active compressional structures and obstruct the eastward or southeastward motion of the Qinghai-Tibetan Plateau at a lithospheric depth scale. There is an echoing relationship between the shallow and deep obstructing structures. Both of the shallow and deep compressional structures have partially transformed the eastward or southeastward motion of the blocks that are controlled by NW strike-slip faults into uplift of the eastern Qinghai-Tibetan Plateau. The synthetic study into the middle and southern segments as a whole will help us to understand the latest tectonic movement and also the dynamics of the earthquake migration in space and time on the mainland of China.