Collision Processes of North China and Siberian Plates: Evidence from LA-ICP-MS Zircon U-Pb Age on Deformed Granite in Xar Moron Suture Zone
-
摘要: 房框子沟花岗质片麻岩NEE向展布于内蒙古林西县双井镇的房框子沟村一带, 是一套侵入到双井片岩中的变质变形侵入体, 其边缘和中央分别为云染状和均质的花岗质片麻岩.利用LA-ICP-MS锆石U-Pb原位定年方法对采自该侵入体边缘和中央的样品进行了定年, 结果表明, 岩浆在271.9±1.6Ma开始侵位于双井片岩中, 在接触带上多发生混合岩化, 造成岩体边缘呈云染状, 在264.8±1.8Ma岩体主体侵位, 之后由于西伯利亚板块与华北板块的持续碰撞缝合, 岩体在应力作用下变形变质形成了今天看到的房框子沟花岗质片麻岩的面貌, 到231±2Ma碰撞基本结束, 西伯利亚板块与华北板块最终拼合.Abstract: The Fangkuangzigou granitic gneisses, extending with NEE trend along Fangkuangzi village in Linxi county, Inner-Mongolia province, are deformed and metamorphosed granites which intruded into the Shuangjing schists. The gneisses are nebulitic and homogeneous separately in its edge and center. The LA-ICP-MS zircon U-Pb dating method was applied to determine the ages of gneisses both from the edge and center. It is indicated that the magma emplacement initiated at about 271.9±1.6Ma ago and intruded into Shuangjing schists, then migmatization and nebulitic structure were induced into the contact zones. The pluton was formed dominantly at 264.8±1.8 Ma ago. The pluton was deformed and metamorphosed into granitic gneiss by the collision betweenthe Siberian and North China plates. The collision was ended until 231±2 Ma ago, then the Siberian and North China plates were finally converged.
-
Key words:
- granitic gneiss /
- zircon /
- LA-ICP-MS dating /
- geochronology /
- Shuangjing /
- Inner-Mongolia
-
图 1 内蒙古林西县双井地区地质简图
1.双井片岩; 2.花岗质片麻岩; 3.志留系西别河组; 4.杏树洼蛇绿岩; 5.二叠系哲斯组; 6.中生代侵入岩; 7.中生代火山岩; 8.第三系玄武岩; 9.第四系; 10.断层; 11.村庄; 12.采样点及编号
Fig. 1. Geological map of Shuangjing area in Linxi county, Inner-mongolia province
图 2 房框子沟花岗质片麻岩边缘(a) 和中央(b) 代表性锆石CL图像和U-Pb年龄
其中白线为比例尺, 长度为50μm, 圆圈表示剥蚀激光束对应的位置, 直径为32μm
Fig. 2. Representative CL images of single zircon grains from edge (a) and center (b) and thier U-Pb ages of the Fangkuangzigou granitic gneiss
图 3 房框子沟花岗质片麻岩边缘(a, b) 和中央(c, d) 的LA-ICP-MS锆石U-Pb谐和图和加权平均年龄
Fig. 3. LA-ICP-MS zircon U-Pb concordia diagram and weighted average age from edge (a, b) and center (c, d) of the Fangkuangzigou granitic gneiss
表 1 云染状花岗质片麻岩(8875)的LA-ICP-MS锆石U-Pb分析结果
Table 1. LA-ICP-MS zircon U-Pb analytic data for nebulitic granitic gneiss (8875)
表 2 均质的花岗质片麻岩(8877)的LA-ICP-MS锆石U-Pb分析结果
Table 2. LA-ICP-MS zircon U-Pb analytic data for homogeneous granitic gneiss (8877)
-
[1] Andersen, T., 2002. Correction of commonlead in U-Pb analyses that do not report 204Pb. Chemical Geology, 192 (1-2): 59-79. doi: 10.1016/S0009-2541(02)00195-X [2] Chen, B., Zhao, G. C., Si mon, W., 2001. Subduction-and collision-related granitoids from southern Sonidzuoqi, Inner Mongolia: Isotopic ages and tectonic implications. Geological Review, 47 (4): 361-367 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-DZLP200104005.htm [3] Hao, X., Xu, B., 1997. Sm-Nd, Rb-Sr isotopic geochronology of the Xilin Gol complexs, Inner Mongolia, China. Geological Review, 43 (1): 101-105 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-DZLP199701015.htm [4] Li, J. Y., Gao, L. M., Sun, G. H., et al., 2007. Shuangjinzi Middle Triassic syn-collisional crust-derived granite in the East Inner Mongolia and its constraint on the timing of collision between Siberian and Sino-Korean paleoplates. Acta Petrologica Sinica, 23 (3): 565-582 (inChinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-YSXB200703006.htm [5] Li, Y. L., Zhou, H. W., Ge, M. C., et al., 2007. Characteristics and genesis of migmatites within the northern Shuangjing micro-plate in the West Lamulun fault zone, Inner-Mongolia Province. J. Mineral. Petrol., 27 (4): 22-29 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-KWYS200704004.htm [6] Li, Y. L., Zhou, H. W., Ge, M. C., et al., 2008. LA-ICP-MS zircon U-Pb dating of migmatite from North Shuangjing schist in Linxi, Inner Mongolia. J. Mineral. Petrol., 28 (2): 10-16 (in Chinese with English abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-KWYS200802005.htm [7] Ludwig, K. R., 1991. Isoplot-A plotting and regression program for radio genic-isotope data. US Geological Survey Open-File Report, 39: 91-445. [8] Pearce, N. J. G., Perkins, W. T., Westgate, J. A., et al., 1997. A compilation of new and published major and trace element data for NIST SRM 610 and NIST SRM 612 glass reference materials. Geostand. Newsl., 21 (1): 115-144. doi: 10.1111/j.1751-908X.1997.tb00538.x [9] Shao, J. A., 1986. The early protozoic ophiolite in middle Inner Mongolia and its implications for reconstruct crust evolution. In: Collection of papers on tectonics of North China Plate (Ⅰ). Earthquake Publishing House, Beijing, 158-171 (in Chinese). [10] Song, B., Zhang, Y. H., Wan, Y. S., et al., 2002. Mount making and procedure of the SHRIMP dating. Geological Review, 48 (Suppl. ): 26-30 (in Chinese with Eng-lish abstract). http://en.cnki.com.cn/Article_en/CJFDTOTAL-DZLP2002S1006.htm [11] Tang, K. D., Zhang, Y. P., 1991. Tectonic evolution of Inner Mongolian suture zone. In: Xiao, X. C., Tang, Y. Q., eds., Tectonic evolution of the southern margin of the Paleo-Asian composite megasuture. Scientific and Technical Publishing House, Beijing, 30-54 (in Chinese). [12] Vavra, G., Gebauer, D., Schmid, R., et al., 1996. Multiple zircon growth and recrystallization during polyphase late carboniferous to triassic metamorphism in granulites of the Ivrea zone (Southern Alps): An ion microprobe (SHRIMP) study. Contrib. Mineral. Petrol., 122 (4): 337-358. doi: 10.1007/s004100050132 [13] Vavra, G., Schmid, R., Gebauer, D., 1999. Internal morphology, habit and U-Th-Pb microanalysis of amphibolite-to-granulite facies zircons: Geochronology of the Ivrena zone (southern Alps). Contrib. Mineral. Petrol., 134 (4): 380-404. doi: 10.1007/s004100050492 [14] Wiedenbeck, M., Alle, P., Corfu, F., et al., 1995. Three natural zircon standards for U-Th-Pb, Lu-Hf, trace elementand REE analyses. Geostand. Newsl., 19 (1): 1-23. doi: 10.1111/j.1751-908X.1995.tb00147.x [15] Wu, Y. B., Zheng, Y. F., 2004. Genesis of zircon and its constraints on interpretation of U-Pb age. Chinese Science Bulletin, 49 (15): 1554-1569. doi: 10.1007/BF03184122 [16] Xu, B., Chen, B., Shao, J. A., 1996. Sm-Nd and Rb-Sr isotopic geochronology of the Xilin Gol complex, Inner Mongolia. Chinese Science Bulletin, 41 (13): 1107-1110. http://www.cnki.com.cn/Article/CJFDTotal-JXTW199613012.htm [17] 陈斌, 赵国春, Simon, W., 2001. 内蒙古苏尼特左旗南两类花岗岩同位素年代学及其构造意义. 地质论评, 47 (4): 361-367. doi: 10.3321/j.issn:0371-5736.2001.04.005 [18] 郝旭, 徐备, 1997. 内蒙古锡林浩特锡林郭勒杂岩的原岩年代和变质年代. 地质评论, 43 (1): 101-105. https://www.cnki.com.cn/Article/CJFDTOTAL-DZLP199701015.htm [19] 李锦轶, 高立明, 孙桂华, 等, 2007. 内蒙古东部双井子中三叠世同碰撞壳源花岗岩的确定及其对西伯利亚与中朝古板块碰撞时限的约束. 岩石学报, 23 (3): 565-582. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200703006.htm [20] 李益龙, 周汉文, 葛梦春, 等, 2007. 西拉木伦断裂带双井微地块北缘混合岩的基本特征及其成因机制讨论. 矿物岩石, 27 (4): 22-29. doi: 10.3969/j.issn.1001-6872.2007.04.005 [21] 李益龙, 周汉文, 葛梦春, 等, 2008. 内蒙古林西县双井片岩北缘混合岩LA-ICPMS锆石U-Pb年龄. 矿物岩石, 28 (2): 10-16. doi: 10.3969/j.issn.1001-6872.2008.02.003 [22] 邵济安, 1986. 内蒙古中部早古生代蛇绿岩及其在恢复地壳演化历史中的意义. 见: 中国北方板块构造论文集编委会, 中国北方板块构造论文集(Ⅰ). 北京: 地质出版社, 158-171. [23] 宋彪, 张玉海, 万渝生, 等, 2002. 锆石SHRI MP样品靶制作、年龄测定及有关现象讨论. 地质论评, 5 (增刊): 26-30. https://www.cnki.com.cn/Article/CJFDTOTAL-DZLP2002S1006.htm [24] 唐克东, 张允平, 1991. 内蒙古缝合带的构造演化. 见: 肖序常, 汤耀庆, 主编. 古中亚复合巨型缝合带南缘构造演化. 北京: 科学技术出版社, 30-54. -
下载:
点击查看大图
计量
- 文章访问数: 3599
- HTML全文浏览量: 98
- PDF下载量: 89
- 被引次数: 0
