|
| 引用本文: | 邹光富, 朱同兴, 贾保江, 李建忠, 冯心涛, 周铭魁.藏南定日白垩纪火山岩岩石学与地球化学初步研究[J].沉积与特提斯地质,2003,(4):62-67.[点击复制] |
| | [点击复制] |
|
| |
|
|
| 本文已被：浏览 342次 下载 236次 |
码上扫一扫！ |
| 藏南定日白垩纪火山岩岩石学与地球化学初步研究 |
| 邹光富,朱同兴,贾保江,李建忠,冯心涛,周铭魁 |
|
|
(1. 成都理工大学, 四川 成都 610059;
2. 成都地质矿产研究所, 四川 成都 610082) |
|
| 摘要: |
| 本文描述了西藏定日白垩纪火山岩的地质、岩石学、岩石地球化学特征和构造造背景。该火山岩岩石类型有蚀变英安岩和蚀变安山岩,其岩石化学成分特征表明岩石为二氧化硅过饱、铝过饱和类型,属亚碱性拉斑玄武岩系列。岩石稀土元素配分曲线呈强烈右倾的轻稀土富集型;微量元素配分模式图呈锯齿状"多隆起"型,类似于岛弧火山岩的微量元素配分模式。综合判定该期火山岩形成于大陆边缘造山带岛弧构造环境。 |
| 关键词: 白垩纪 火山岩 定日 西藏南部 |
| DOI： |
| 附件 |
| 投稿时间：2003-09-20 |
| 基金项目:中国地质调查局1∶25万《聂拉木县幅》区域地质调查。 |
|
| Petrography and geochemistry of the Cretaceous volcanic rocks in Tingri, southern Xizang |
| ZOU Guang-fu, ZHU Tong-xing, JIA Bao-jiang, LI Jian-zhong, FENG Xin-tao, ZHOU Ming-kui |
(1. Chengdu University of Technology, Chengdu 610059, Sichuan, China;
2. Chengdu Institute of Geology and Mineral Resources, Chengdu 610082, Sichuan, China) |
| Abstract: |
| The geology, petrography, geochemistry and tectonic settings are described for the Cretaceous (volcanic) rocks in Tingri, southern Xizang. The volcanic rocks consist of altered dacite and andesite, which are assigned to the subalkaline, silica- and aluminum-oversaturated tholeiite series. The REE amounts range (between) (383.17)×(10-6) and (266.52)×(10-6). The REE distribution curves display highly right-leaning LREE-enriched patterns, whereas the trace element distribution patterns exhibit zigzag "polydome" patterns, similar to those for island-arc volcanic rocks. The trace element compositions are plotted into the volcanic arc field in the Rb-(Yb+Ta) diagram, and the lithochemical compositions fall into the island-arc orogenic basalt and andesite fields in the ATK diagram. The preceding results of research show that the Cretaceous volcanic rocks in the study area are interpreted to be formed in a continental marginal orogenic island-arc tectonic setting. |
| Key words: Cretaceous volcanic rock Tingri southern Xizang |
|
|
|
|
|