青藏高原冈底斯岩浆弧的分带性及其地质意义  

Zonality of the Gangdise magmatic arc on the Qinghai-Tibet Plateau and its geological significance

作　　者：卢书炜[1] 张良[1] 任建德[1] 张彦启[1] 白国典[1] 

机构地区：[1]河南省地质调查院

出　　处：《地质通报》2004年第9期1023-1032,共10页Geological Bulletin of China

基　　金：中国地质调查局<1:25万尼玛区幅;热布喀幅区域地质调查>项目(编号:200013000140)成果。

摘　　要：冈底斯岩浆弧中段岩浆岩明显可分为相对集中又有所套叠的南北2个岩带。公穷松多-郎那花岗岩带位置略偏南,被晚期旋回林子宗群火山岩不整合覆盖。岗在-青都花岗岩带位置略偏北,带内各岩体均侵入于林子宗群火山岩。公穷松多岩带(早期旋回)从晚侏罗世开始,至晚白垩世早期结束;青都岩带(晚期旋回)从晚白垩世晚期开始,至始新世结束。2个岩带岩石分别从俯冲型产物开始,至后碰撞型产物结束,为2个较完整的岩浆旋回,暗示雅鲁藏布江构造带构造演化历程的复杂性。Magmatic rocks in the central segment of the Gangdise magmatic arc can be divided into the south and north belts, which are relatively concentrated but telescoped to a certain extent. The Gongqiongsongduo-Langna granite belt located in the south is overlain unconformably by volcanic rocks of the Linzizong Group of the late cycle. The Gangzai-Qingdu granite belt is located in the north and all the rock bodies in the belt are intruded by the Linzizong Group volcanic rocks. The formation of the Gongqiongsongduo granite belt (in the early cycle) began in the Late Jurassic and ended in the early Late Cretaceous, while the formation of the Qingdu granite belt (in the late cycle) began in the late Late Cretaceous and ended in the Eocene. The rock types in the two rock belts represent two relatively complete magmatic cycles, beginning with the subduction-type product and ending with the post-collision-type product, implying the complexity of tectonic evolution process of the Yarlung Zangbo tectonic belt.

关 键 词：冈底斯岩浆岩 分带性 同位素年龄 成因类型 地质意义 

分 类 号：P588.121[天文地球—岩石学]