|
文摘
|
在一定条件下,花岗岩对于研究古大洋板块俯冲消减及陆-陆碰撞等板块演化过程具有重要的意义。拢布村花岗岩体位于西藏南冈底斯带中段,有关南冈底斯带花岗岩类形成年代仍存在不同认识。通过LA-ICP-MS锆石U-Pb测年获得拢布村花岗岩的形成年龄为157.0Ma±2.9Ma,表明南冈底斯带存在晚侏罗世岩浆活动。拢布村花岗岩富集Rb、Ba、Th、U、K等大离子亲石元素,亏损Nb、Ta、Ti等高场强元素,显示出岛弧岩浆岩的特征,指示晚侏罗世南冈底斯带存在新特提斯洋北向欧亚大陆的早期俯冲运动。研究表明,拢布村花岗岩为洋壳板块俯冲消减作用背景之下上覆地幔楔部分熔融的产物。 |
|
其他语种文摘
|
Granite has important significance for the study of ocean plate subduction and continent-continent collision under certain conditions. Longbucun granite belongs to the middle part of Southern Gangdise Belt, and the formation age of the granitoids in this belt is a subject of much controversy. The LA-ICP-MS U-Pb zircon age of Longbucun granite is 157.0Ma±2.9Ma, which shows that there existed granitic magmation in the Late Jurassic in Southern Gangdise Belt. Longbucun granite is enriched in such large-ion lithophile elements as Rb, Ba, Th, U and K and depleted in the high field strength elements like Nb, Ta and Ti, suggesting the features of island arc magmatic rocks and indicating that there existed an early-stage northward subduction of the Neo-Tethys Ocean to the Eurasian Plate in the Late Jurassic period. Longbucun granite was formed by partial melting of the mantle wedge under the subduction of the Neo-Tethys plate. |
|
来源
|
地质通报
,2013,32(9):1362-1370 【核心库】
|
|
关键词
|
拢布村花岗岩
;
锆石U-Pb
;
LA-ICP-MS
;
新特提斯洋
;
南冈底斯带
|
|
地址
|
1.
中山大学海洋学院, 海洋石油勘探开发广东省普通高校重点实验室, 广东, 广州, 510275
2.
中山大学地球科学系, 广东, 广州, 510275
|
|
语种
|
中文 |
|
文献类型
|
研究性论文 |
|
ISSN
|
1671-2552 |
|
学科
|
地质学 |
|
基金
|
国土资源部中国地质调查局项目
;
国家973计划
|
|
文献收藏号
|
CSCD:4946013
|
了解气象卫星更多信息，请访问