青藏高原比如地体与措勤地体相对古构造位置判别

本文采用蚀源区判别图解QFL和QpLsLv、微量元素图解Th -Co -Zr/10、常量元素图解K2O/Na2O -SiO2 和野外地质实测剖面等方法 ,对比如、措勤地体的构造演化进行了分析。发现并证实了在T3-J1 以前比如地体位于措勤地体的北部 :J2 -3 时随着班—恕缝合带的拉张 ,比如地体开始右旋向东滑动 :一直延续到J3-K1 时 ,班—怒缝合带闭合 ,比如地体才就位于目前位置。最后应用1/ZTR指数推测了比如地体在J2 -3 时滑移点的大致位置 (E90°49,N31°34)。

RECOGNITION OF ANCIENT TECTONIC RELATIVE LOCATION OF THE BIRU TERRAIN AND CUOQIN TERRAIN

Using the sandstone samples of C K formations in the Biru Terrain,Cuoqin Terrain and their peripheral areas,the authors make the tectonics property maps,QFL and QPLsLv of erosion areas,trace elements relationship map,Th Co Zr/10,common elements relationship map and K2O/Na2O SiO2 and by combination of field testing stone cross profile,analyze tectonic evolution.It indicates that before T3-J1 the Biru Terrain was located north of the Cuoqin Terrain.Then with the Bangonghu Nujiang suture(BNS)extending in J2 3,the Biru Terrain started to strike slip toward east.Up to J2 3 the Bangonghu Nujiang suture(BNS)had nearly closed,and the Biru Terrain fixed to its present location.According to the 1/ZTR factor the authors also deduced the approximate strike slip location,present E90°49′N31°34′,in J2 3.