【摘要】 青藏高原东北缘所在的柴达木-祁连活动地块内的晚第四纪活动构造可以划分为主边界左旋剪切构造带、块内次级右旋剪切构造带和挤压会聚构造带等三种基本类型。在区域北东向构造应力作用下,块体发生了NE向的挤压缩短、顺时针方向的旋转和向SEE方向的挤出等构造变形。在块体内部形成了挤压推覆构造、次级剪切构造、剪切压扁构造和弧形挤出构造等四种典型的构造转换方式,实现不同方向与不同性质活动构造之间的转换平衡。更多还原

【Abstract】 Late Quaternary active tectonics on the northeastern margin of the Qinghai—Xizang (Tibet) Plateau belongs to the Qaidam-Qilian active crustal block. They can be divided into three fundamental types: main-boundary left-lateral shear tectonic zone, secondary right-lateral shear zone within a block, and compressional and convergent tectonic zone. Under the action of the NE-striking regional structural stress, the crustal block was subjected to obvious tectonic deformation, including NE-oriented compressional and shortening, clockwise rotation and extrusion along the SSE direction and so on. Within the block, 4 kinds of structural transformation modes were formed: thrust nappe structure, secondary shear structure, shear and flaser structure, and arc extrusion structure, thus reaching a transformation balance between active structures with different directions and different features.更多还原