【摘要】 格仁错断裂是西藏中部的一条重要断裂,在对该断裂进行ETM遥感影像解译基础上,分析总结认为该断裂带为由一组北西走向的雁列断裂组成.根据野外实地考察断裂对冰水冲积扇、冲积阶地、冲沟及山脊位错等判断,北西向主要断裂以右旋为主,兼有张性正断性质,但在不同段落断裂结构及活动性质有所不同.根据断裂结构和活动性差别,并考虑受南北向申扎—定结地堑活动的影响,可将断裂带划分成3个不同段落:西北段地貌上表现为狭窄的谷地,断裂影像表现为连续平直线性特征,主要为右旋走滑性质,张性正断性质不明显;中段地貌表现为较宽的河湖带,为断裂控制的半地堑和地堑构造,断裂张性正断活动较强;东南段地貌上为快速冲填的狭窄河谷带,为两条断裂控制的双边地堑,并受地堑向东扩展的影响,整体沉降接受充填,断裂活动性质总体表现不强.据此地貌特点推测,断裂带是深部竖直右旋走滑断裂由于张力作用,浅部变为北窄南宽喇叭口的正花状构造模式所致.更多还原

【Abstract】 Gyaring Co fault zone is an important fault in central Qingzang plateau.Result of analysis of ETM remote sensing images and field observations indicate that the fault consists of a series of NW--SE echelon branches.From the offset of alluvium fans,alluvium terrace,stream channels and mountain ridge,we can see that main faults manifested activity mainly in dextral slip with subsidiary extension,although there are some difference between segments.The fault zone can be divided into three segments based on fault structure and activity,taking the activity of Shenzha--Dingjie graben into consideration.The northwestern segment is a right-lateral strike-slip fault characterized by continuous linear feature in the images,with relatively weak extensional activity.The middle segment is a wide rift valley bounded by two lateral faults with strong extensional activity.The southeastern segment is a narrow rift valley controlled by lateral faults with weak activity,and the valley subsided as a whole due to east-west graben extension.Based on the geomorphologic characteristics of the fault zone a fault model may be assumed:the deep part of the fault moves in dextral strike-slip and its shallow part changes to normal flower structure owing to the extension.更多还原