| 摘要: |
| 在青海西金乌兰湖地区移山湖和倒流沟一带发现的辉绿岩墙,侵入于泥盆系拉竹龙组变质石英砂岩、长石石英砂岩和元古宇宁多群灰白色白云母石英片岩、黑云母石英片岩中,岩石类型为辉绿岩、辉长辉绿岩,结合同位素测年及古生物证据分析其地质时代为晚泥盆世,可能与古特提斯北部河卡山东段克觉杂尔根基性岩墙群一样,反映了可可西里地区壳幔演变过程,是古陆块裂解、西金乌兰洋初始形成的证据。 |
| 关键词: 西金乌兰湖地区 西金乌兰洋 晚泥盆世 辉绿岩墙 初始裂解 青海 |
| DOI： |
| 附件 |
| 投稿时间：2004-02-12 |
| 基金项目:中国地质调查局“1∶25万可可西里湖幅(I46C001001)地调项目成果”(2000130009211)。 |
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| The Late Devonian diabase dike swarms in the Yishan Lake-Daoliugou zone, Xijir Ulan Lake area, Qinghai: Evidences for the initial breakup of the Xijir Ulan Ocean |
| ZHU Ying-tang, YIN Hai-sheng, YANG Yan-xing, GUO Tong-zhen, PENG Wei, CHEN Hai-qing |
(1. Chengdu University of Technology, Chengdu 610059, Sichuan, China;
2. Qinghai Institute of Geological Survey, Xining 810012, Qinghai, China) |
| Abstract: |
| The diabase dike swarms found in the Yishan Lake-Daoliugou zone, Xijir Ulan Lake area, Qinghai are emplaced in the metamorphic quartz sandstone and feldspar quartz sandstone in the Devonian Lazhuglung Formation, and grayish white muscovite quartz schist and biotite quartz schist in the Proterozoic Ningduo Group. The rock types include diabase and gabbro-diabase, which exhibit the crystallization differentiation of the magmas, and may be traced back to the Late Devonian. These diabase dike swarms, just like the basic dike swarms in (Kejuezargen), eastern Heka Mountains, Qinghai, may record the crust-mantle evolution in the Hoh Xil region, and attest to the breakup of the palaeocontinent and initiation of the Xijir Ulan Ocean. |
| Key words: Xijir Ulan Lake area Xijir Ulan Ocean Late Devonian diabase dike swarms initial breakup Qinghai |
