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| 川西地区甲基卡穹隆的构造变形特征 |
| 武文辉,詹涵钰,秦宇龙,李峥,徐云峰,申伟 |
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(1. 稀有稀土战略资源评价与利用四川省重点实验室, 四川 成都 610081;
2. 四川省地质调查院, 四川 成都 610081;
3. 四川省地矿局 113 地质队, 四川 泸州 646000) |
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| 摘要: |
| 甲基卡穹隆因其丰富的锂辉石资源而闻名，在华北、扬子和羌塘3个板块之间的南北向和东西向双向收缩背景下，形成了其复杂的变形特征。穹隆顶部地层平缓，向外逐渐变陡，总体为同心圆状向外倾的复式背斜。顶部发育有A型等斜平卧褶皱、肠状石英脉及对称型压力影；翼部变质矿物多被拉伸旋转而呈不对称状，表现出向穹隆周围的正向剪切运动；穹隆外围地层产状较陡，多发育直立紧闭褶皱及倒转褶皱。总体来说，甲基卡穹隆岩浆底辟作用前，先后经历了南北向及东西向的挤压，成穹后再一次经历南北和东西向挤压的两期构造运动，属于构造变形与岩浆作用的共同产物。 |
| 关键词: 甲基卡穹隆 变形特征 岩浆 底辟 |
| DOI： |
| 附件 |
| 投稿时间：2017-07-12修订日期：2017-10-12 |
| 基金项目:中国地质调查局《四川康定瓦多-龙古地区H47E010021、H47E010022、H47E011021、H47E0110224幅区域地质调查》（子项目编码：DD20160074-02）、《四川康定-道孚-雅江稀有金属整装勘查区矿产调查与找矿预测》项目（121201004000150017－93）、《西南三江有色金属资源基地调查项目》（项目编号DD20160016）项目资助 |
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| Structural deformation of the Jiajika dome in western Sichuan |
| WU Wen-hui, ZHAN Han-yu, QIN Yu-long, LI Zheng, XU Yun-feng, SHEN Wei |
(1. Key Laboratory of the Evaluation and Utilization of Strategic Rare Metals and Rare Earth Resources of Sichuan Province, Chengdu 610081, Sichuan, China;
2. Sichuan Institute of Geological Survey, Chengdu 610081, Sichuan, China;
3. No. 113 Geological Party, Sichuan Bureau of Geology and Mineral Resources, Luzhou 646000, Sichuan, China) |
| Abstract: |
| The Jiajika dome in western Sichuan is famous for its abundant spodumene resources. Both the NS- and EW-trending convergence of the North China,Yangtze and Qiangtang blocks resulted in the complex structural deformation of the Jiajika dome. Generally,the Jiajika dome appears as a concentric anticlinorium where the coral strata are gentle,and become gradually steeper outwards. There are A-type isoclinal recumbent folds,ptygmatic quartz veins and symmetrical pressure shadows on the top of the dome. The metamorphic minerals on the limbs are almost strenched and rotated into asymmetrical formes,displaying the nature of a positive shear movement from the limbs outwards. The vertical tight folds and overturned folds occur in the steeper strata around the dome. On the whole,the Jiajika dome is interpreted as the products of joint tectonism and magmatism,and has successively experienced two phases of tectonic movements,i. e.,two phases of NS- and EW-trending tectonic compression. |
| Key words: Jiajika dome deformation magma diaper |