摘要
古近纪业阿供组火山岩分布于西藏东部类乌齐镇业阿供村,LA-ICP-MS锆石U-Pb年龄为30.54±0.8Ma,岩石具有高碱、低Ti的特征,在SiO2-K2O图解中位于钾质岩区,属于碱性钾质岩。岩石地球化学特征表明,业阿供组钾质火山岩很可能源于古俯冲流体交代的富集地幔源区经过部分熔融作用,形成于碰撞后的板内构造环境。
Volcanic rocks in Yeegong Formation in Paleogene was located in Yeegong village of Leiwuqi town in Eastern Tibet, Zircon U-Pb age by LA-ICP-MS was 30.54 ± 0. 8Ma, the rocks were characteristic of high alkali and low Ti and located in potassic rock area in a diagram of SiO2-K2 O, so the volcanic rock in Yeegong Formation belonged to alkaline potassium rock. Rock geochemical charac- teristics demonstrated that the potassium volcanic rock was originated from the enriched mantle source metasomatized by the paleo-sub- duction fluid and formed in a plate interior tectonic environment of post collision.
出处
《地质学刊》
CAS
2011年第3期241-246,共6页
Journal of Geology
基金
中国地质调查局项目:西藏1:5万协通
类乌齐镇
瓦昌达
类乌齐县幅区调(1212010710211)
关键词
构造环境
岩石地球化学
钾质火山岩
业阿供组
类乌齐地区
藏东
Tectonic environment
Rock geochemistry
Potassic volcanic rocks
Yeegong Formation
Leiwuqi area
Eastern Tibet
