对藏北羌塘地体阿木岗群的新认识  

The New Understanding of Amugang Group of Qiangtang Terrain in North Tibet

作　　者：和钟铧[1] 王天武[1] 李才[1] 杨德明[1] 

机构地区：[1]长春科技大学地球科学学院,吉林长春130061

出　　处：《世界地质》2000年第1期1-7,共7页World Geology

摘　　要：依据地质填图和实测剖面获得的资料 ,对羌塘地体阿木岗群的层序特征、岩石地球化学特征、变质作用特征等方面进行了研究 ,并根据变质岩与盖层之间的角度不整合关系 ,火山 -沉积变质岩的Sm -Nd年龄对阿木岗群的原岩时代和变质年龄进行了重新厘定 ,得出其原岩为一套陆源碎屑岩和少量火山岩 ,经历了三期变质作用的演化 ,火山 -沉积变质岩Sm -Nd年龄为 2 68.6Ma。On the basis of the actual data obtained from geological mapping and measured section, the authors have studied the succession, petrochemistry and metamorphism of Amugang group According to the angular discordance between metamorphic rocks and cap rocks and the Sm-Nd age of volcano-sedimentary metamorphic rock, the ages of primitive rock and metamorphism of Amugang group can be ascertained again The results are that primitive rocks are a set of terrigemous detrital rocks and minor volcanic rocks, which suffered from three stages of metamorphism, the Sm-Nd age of volcano-sedimentary metamorphic rock is 268.6 Ma.

关 键 词：阿木岗群 变质作用 羌塘地体 变质岩 

分 类 号：P588.3[天文地球—岩石学] P544[天文地球—地质学]