| 保山地体寒武纪基性火山岩及其大地构造意义 |
| |
| 引用本文： | 徐晓尹,蔡志慧,陈希节,李化启,曹汇,黄学猛,段向东.保山地体寒武纪基性火山岩及其大地构造意义[J].地质通报,2017,36(7):1104-1117. |
| |
| 作者姓名： | 徐晓尹 蔡志慧 陈希节 李化启 曹汇 黄学猛 段向东 |
| |
| 作者单位： | 1. 中国地质大学(北京)能源学院, 北京 100083;2. 中国地质调查局大陆动力学研究中心/中国地质科学院地质研究所, 北京 100037;3. 中国地震局地壳应力研究所, 北京 100085;4. 云南省国土资源规划设计研究院, 云南 昆明 650216 |
| |
| 基金项目： | 国家自然科学基金项目《青藏高原东南缘点苍山水平与垂直韧性剪切带的关系及运动学启示》（批准号：41302166）、中国地质调查局项目《特提斯-青藏高原科技长廊和主要成矿带构造背景综合地质调查》（编号：DD20160022）和中国地质科学院地质研究所基本科研业务费项目《缅甸抹谷及滇西早白垩世岩浆作用及对特提斯演化的启示》（编号：J1621） |
| |
| 摘 要： | 保山地体位于青藏高原东南缘。有关保山地体的岩浆作用研究大多集中在中生代及新生代,针对古生代岩浆作用的讨论较少。对云南省保山邦迈地区蒲满哨群中变质基性岩的锆石U-Pb年代学、地球化学及Sm-Nd同位素组成进行了研究。这些变质基性岩可分为2组:一组为斜长角闪岩,另一组为黑云斜长角闪岩。锆石U-Pb测年结果表明,斜长角闪岩的形成时代为536.7Ma,黑云斜长角闪岩的形成时代为532.0Ma。地球化学特征显示,斜长角闪岩的原岩为玄武安山岩,黑云斜长角闪岩的原岩为碱性玄武岩。稀土和微量元素配分曲线及多种构造环境判别图解显示,二者分别具有富集型大洋中脊玄武岩和洋岛玄武岩的地球化学特征。结合区域大地构造背景认为,保山地体邦迈变质基性岩为洋脊俯冲的产物。在新元古末期—早古生代,保山地体与拉萨地体、喜马拉雅地体等类似,皆位于冈瓦纳大陆边缘,且共同经历了增生造山过程。
|
| 关 键 词： | 青藏高原东南缘 保山地体 早古生代 变质基性岩 增生作用 冈瓦纳 |
| 收稿时间： | 2016/10/12 0:00:00 |
| 修稿时间： | 2017/5/9 0:00:00 |
Characteristics of the Paleozoic metabasite in Baoshan Terrane:Implications for the tectonic evolution |
| |
| XU Xiaoyin,CAI Zhihui,CHEN Xijie,LI Huaqi,CAO Hui,HUANG Xuemeng and DUAN Xiangdong.Characteristics of the Paleozoic metabasite in Baoshan Terrane:Implications for the tectonic evolution[J].Geologcal Bulletin OF China,2017,36(7):1104-1117. |
| |
| Authors: | XU Xiaoyin CAI Zhihui CHEN Xijie LI Huaqi CAO Hui HUANG Xuemeng and DUAN Xiangdong |
| |
| Institution: | 1. China University of Geosciences, Beijing 100083, China;2. Center for Continental Dynamics, CGS;Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China;3. Institute of Crustal Dynamics, China Earthquake Administration, Beijing 100085, China;4. Yunnan Land Resources Planning and Design Institute, Kunming 650216, Yunnan, China |
| |
| Abstract: | The Baoshan Terrane is located on the southeastern margin of the Tibetan Plateau. Previous studies of the magmatism of the Baoshan Terrane were mainly focused on the Mesozoic and Cenozoic periods, whereas the study of the Paleozoic magmatism was relatively insufficient. In this paper, zircon U-Pb geochronology, geochemistry and Sm-Nd isotopes are presented for metabasite of Pumanshao Group in Bangmai area, Baoshan, Yunnan Province. The metabasites can be divided into two groups:amphibolite and bi-otite-plagioclase amphibolite. Zircon U-Pb geochronologic study shows that the two groups were formed at 536.7Ma and 532.0Ma, respectively. Geochemical characteristics indicate that the protolith of amphibolite was basaltic andesites and that of biotite-plagio-clase amphibolite was alkaline basalt. REE and trace element distribution and diagrams for discriminating the tectonic settings reveal that the two groups have geochemical features of E-MORB and OIB, respectively. Combined with the regional tectonic setting, the authors hold that metabasites are products of Proto-Tethyan ridge subduction. During Late Neoproterozoic-Early Paleozoic, like things in the Lasha and Himalaya terranes, the Baoshan Terrane was situated on the margin of Gondwana too and experienced accre-tionary orogeny. |
| |
| Keywords: | southeastern Tibetan Plateau Baoshan Terrane Early Paleozoic metabasite accretion Gondwana |
| 本文献已被 CNKI 等数据库收录！ |
| 点击此处可从《地质通报》浏览原始摘要信息 |
| 点击此处可从《地质通报》下载免费的PDF全文 |
|
