Offset river is one of the characteristic landforms along active strike-slip fault. Whereas because of various factors such as natural meander, river capture, etc, difficulties exist while interpreting slip motion and offset amount using landforms of offset rivers. In this study, we introduced the systematic offset of bedrock channels as a method to analyze offset rivers along strike-slip fault. Systematic offset of bedrock channels is the result of coupling between tectonic process and surface process. It also describes the phenomenon of synchronous accumulation both of the offset amount and the upstream length because of head-ward erosion. Based on the interpretation, measuring and statistics of the offset river landforms, it is found that systematic offset of bedrock channels have developed along the Ganzi-Yushu, Xianshuihe and eastern Kunlun fault zones on the eastern Tibetan plateau. There is a linear relationship between the upstream length (L), measured from the headwater to the fault, and the offset amount (D):D=a·L. This study provides useful implications to the role of strike-slip faults during the geomorphic evolution of the eastern Tibetan plateau.

Based on the field work and seismic reflection profiling data,the paper investigates the deformation characteristics of the Longquanshan Fault zone.The main thrust fault of the Longquanshan Fault belt lies in the west of the Longquanshan anticline and has different properties from northeast to southwest.In the north segment and south segment of the Longquanshan Fault,the plane of fault dips to northwest and is uncontinuous,but in the middle segment,the plane of fault dips to southeast and is continuous.Therefore,the middle part of the fault is the main segment of the Longquanshan Fault.Structural geometries of the middle segment of the fault suggest classical fault-propagation folding and the fault ruptured along different axial directions.Historical earthquakes and geomorphological response to activity of the Longquanshan Fault indicate that the fault was active from the early Pleistocene to late Pleistocene,and its activity is weak since the late Pleistocene,and gradually decreases from south to north.

On the basis of systematical observation on mylonites in hundred of fault zones or more in eastern China and with referring to different divisional views of some researchers for mylonites categories,authors have stressed such three factors on which classification of mylonites depends as the texture,the mechanical genesis and the physical character of fault rocks.Obviously,mylonites which may be included in ductile deformation are based upon the characters of physics and mechanics.Actually,these mylonites may be also divided into three categories,shallow,low temperature and brittle deformation mylonite,i.e.B type;moderate-high temperature and ductile mylonite,i.e.D type;deep,high temperature viscous mylonite i.e.V type.As mentioned above,each category of the mylonite shows the different typical character.B type (brittle-tracture type) is of mylonitic texture,the D type (ductile-gliding type),of subgrain structure,and the V Type (viscous-flow type),of flow structure.These properties are correlative and may have a transition each other as well.In the studied categories,authors mainly describe and compare the B and D types of the mylonite.