青藏高原北羌塘地区古近纪火山岩中埃达克岩的地球化学特征及其构造意义

赵振明; 李荣社; 计文化; 伊海生; 林金辉; 朱同兴

青藏高原北羌塘地区古近纪火山岩中埃达克岩的地球化学特征及其构造意义

1.
西安地质矿产研究所, 陕西西安 710054
2.
成都理工大学沉积地质研究所, 四川成都 610059
3.
成都地质矿产研究所, 四川成都 610082

基金项目:

中国地质调查局“青藏高原北部空白区基础地质综合研究”项目 1212010510110

详细信息

作者简介:
赵振明(1965-), 男, 硕士, 从事构造和环境方面的工作. E-mail: xazzhenming@cgs.gov.cn

中图分类号: P542
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出版历程
- 刊出日期: 2007-09-25

The Characteristics of Geochemical and Its Tectonic Significance from the Adakite of Palaeogene Volcanic Rocks in Northern Qiangtang Area, Qinghai-Tibetan Plateau

1.
Xi′an Institute of Geology and Mineral Resources, Xi′an 710054, China
2.
Chengdu University of Technology, Institute of Sedimentary Geology, Chengdu 610059, China
3.
Chengdu Institute of Geology and Mineral Resources, Chengdu 610082, China

摘要

摘要: 为了研究青藏高原北羌塘地区分布的新生代火山岩形成的时代、物质来源和构造环境, 通过各种年代学和地球化学测试方法获得的资料进行综合研究, 结果表明该地区的火山岩主要形成时代为古近纪, 常量、微量和稀土元素特征显示该区发育一定比例的标准埃达克岩(adakite), 代表地区的12件埃达克岩样品, 其SiO₂含量≥56%(59.05%~67.80%), Al₂O₃≥15%(15.43%~16.63%), MgO < 3%(0.47%~2.98%, 1件样品3.21%), Mg#>20(21.2~56.5), Na₂O/K₂O>1(1.03~1.76), Sr>400×10^-4(609.6×10^-6~3008.0×10^-6), Y≤18×10^-6(4.53×10^-6~13.76×10^-6), Yb≤1.9×10^-6(0.44×10^-6~1.35×10^-6), Sr/Y≥40(44.3-314.68), La/Yb≥20(20.11-69.26), δSr正异常(1.02~7.66, 3件样品0.82、0.93、0.97), δEu正异常或微弱的负异常(0.77~1.36), LREE富集, HREE亏损, 高场强元素HFSEs(Nb、Ta、Ti)明显亏损⁸⁷Sr/⁸⁶Sr>0.704(0.707101-0.707923), ¹⁴³Nd/¹⁴⁴Nd < 0.5126(0.512382-0.512448)⁴⁰K-⁴⁰Ar、⁴⁰Ar-³⁹Ar测定时代分别为28.2~32.2Ma, 38.1~46.8Ma.上述特征除表明该套古近系埃达克岩岩浆源处于加厚的下地壳环境外, 可能还代表了在高原演化过程中, 北羌塘地区滞留在下地壳和上地幔的“洋壳残片”部分熔融并在地表喷发的构造过程.
- 青藏高原 /
- 北羌塘 /
- 古近系 /
- 埃达克岩
Abstract: Studies on the formation times, resources and tectonic environment of the Cenozoic volcanic rocks in the northern Qiantang area, Qinghai-Tibetan Plateau, formed mostly in Plaeogene, show that these rocks have presented characteristics of typical adakite, according to major and trace elements data tested by many dating and geochemical methods. Of the 12 typical adakite samples in important area, SiO₂≥56%(59. 05%-67. 80%), Al₂O₃≥15%(15.43%-16.63%), MgO < 3% (0. 47%-2. 98%, 1 sample is 3.21%), Mg#>20(21.2-56.5), Na₂O/K₂O>1(1.03-1.76), Sr>400 × 10^-6 (609. 6 × 10^-6-3 008. 0× 10^-6), Y≤18 × 10^-6 (4. 53 × 10^-6-13.76 × 10^-6), Yb≤1. 9 × 10^-6 (0.44 × 10^-6-1.35 × 10^-6), Sr/Y≥ 40(44. 3-314. 68), La/Yb≥20(20. 11-69. 26), δSr positive anomaly(1.02-7.66, 3 samples are 0. 82, 0. 93, 0. 97), δEu positive anomaly or weak anomaly(0. 77-1.36), LREE enrichment, HREE depletion, HFSEs (Nb, Ta, Ti) strong depletion, ⁸⁷Sr/⁸⁶Sr>0. 704(0. 707 101-0. 707 923), ¹⁴³Nd/¹⁴⁴Nd < 0. 512 6(0. 512 382-0. 512 448), ⁴⁰K-⁴⁰Ar, ⁴⁰Ar-³⁹Ar ages are 28. 2-32.2 Ma, 38. 1-46. 8 Ma. The above geochemical features of adakite indicate a primitive magmatic generation process responsible for the partial melting of lower thickened crust of northern Qinghai-Tibetan Plateau and perhaps also represent the process in which the remains in lower crust-up mantle melted and erupted in surface after the subduction of ocean crust in the plateau evolvement during early period.
- Qinghai-Tibetan plateau /
- northern Qiangtang area /
- Palaeogene /
- adakite

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图 1 青藏高原北羌塘地区古近系火山岩分布

①乌兰乌拉湖地区氩-氩法测年4个样品由中国地震局地质研究所测试, 钾-氩法测年1个样品由成都地质矿产研究所测试; ②多格错仁地区氩-氩法测年1个样品由中国科学院广州地球化学研究所测试, 钾-氩法测年5个样品由国土资源部中南矿产资源检测中心测试; ③黑虎岭地区钾-氩法测年2个样品由宜昌地质矿产研究所测试. 图中火山岩形状和断层线以潘桂棠和丁俊(2004)为准

Fig. 1. Map of Palaeogene volcanic rocks in the northern Qiangtang area of Qinghai-Xizang plateau

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图 2 SiO₂-(K₂O+Na₂O)(a)和SiO₂-K₂O(b)图解

Fig. 2. SiO₂-(K₂O +Na₂O)(a) and SiO₂-K₂O (b) diagrams

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图 3 Na-K-Ca图解(a)和埃达克岩MgO-SiO₂图解(b)

Fig. 3. Na-K-Ca ternary diagram (a) and The adakites MgO-SiO₂ diagram (b)

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图 4 埃达克岩Sr /Y-Y图解(据Defant and Drummond, 1990; Defant et al., 2002)

Fig. 4. Sr /Y-Y diagrams for the adakites

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图 5 微量元素蛛网图

a. 乌兰乌拉与多格错仁岩区; b. 黑虎岭岩区

Fig. 5. Spider diagrams of primitive mantle normalized trace element distribution patterns

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图 6 微量元素蛛网图(乌兰乌拉与多格错仁岩区)

Fig. 6. Roke normalized trace element distribution patter

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图 7 埃达克岩稀土分配曲线(a)和埃达克岩La /Sm-La图解(b)

Fig. 7. Diagrams of chondrite normalized rare each element distribution patterns (a) and discriminating diagram of La /Sm-La for the adakites (b)

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表 1 青藏高原北羌塘地区古近系埃达克岩元素地球化学测试数据

Table 1. Major and trace element analy ses of Palaeogene adakite from the northern Qiang tang area of Qinghai-Xizang plateau

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表 2 新生代火山岩Sr、Nd、Pb同位素组成

Table 2. Compositions of Sr、Nd、Pb isotope for the Cenozic rocks

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表 3 青藏高原北羌塘地区部分火山岩同位素年龄数据表

Table 3. The part of isotopic ages of volcanic rocks from the northern Qiangtang area of Qinghai-Xizang Plateau

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参考文献(59)

Bu, J. J., Duan, Q. F., 2006. Geological characte ristics of the Bangmai Sb-Au occurrence in the southern part of Chibuzhang Co., northern Tibet, China, and its significance. Geological Bulletin of China, 25(1-2): 273-276 (in Chinese with English abstract).
Castillo, P. R., 2006. An overview of adakite petrogenesis. Chinese Science Bul letin, 51(3): 258-268.
Chi, X. G., Li, C., Jin, W., et al., 1999. Spatial-temporal evolution of cenozoic volcanism and uplifting in North Tibet. Geological Review, 45 (Suppl. ): 978-986 (in Chinese with English abstract).
Defant, M. J., Drummond, M. S., 1990. Derivation of some moder arc magmas by melting of young subducted lithosphere. Nature, 347: 662-665. doi: 10.1038/347662a0
Defant, M. J., Drummond, M. S., 1993. Mount St. Helens : Potential example of the partial melting of the subducted lithosphere in avolcanicarc. Geology, 21: 541-550.
Defant, M. J., Xu, J. F., Kepezhinskas, P., et al., 2002. Adakites : Some variations on a theme. Acta Petrologica Sinica, 18(2): 129-142.
Deng, W. M., 1998. Cenozoic intraplate volcanic rocks in the northern Qinghai-Xizang plateau. Geological Publishing House, Beijing, 1-168 (in Chinese).
Kay, R. W., Kay, S. M., 2002. Andean adakites: Three ways to make them. Acta Petrologica Sinica, 18(3): 303-311.
Lai, S. C., 2003. Identification of the Cenozoic adakitic rock association from Tibetan plateau and its tectonic significance. Earth Science Frontiers, 10(4) : 407-415 (in Chinese with English abstract).
Lai, S. C., Liu, C. Y., 2001. Enriched uppe rmantle and eclogitic lower crust in North Qiang tang, Qinghai-Tibet plateau. Acta Petrologica Sinica, 17(3): 459-468 (in Chinese with English abstract).
Lai, S. C., Liu, C. Y., O′Reilly, S. Y., 2001. Petrogenesis and its significance to continental dynamics of the Neogene high-potassium calc-alkaline volcanic rock association from north Qiang tang, Tibetan Plateau. Science in China (Ser. D), 44(s1): 45-55. doi: 10.1007/BF02911970
Lai, S. C., Liu, C. Y., Yi, H. S., 2003. Geochemistry and petrogenesis of cenozoic andesite-dacite asso ciations from the Hoh Xil region, Tibetan plateau. International Geology Review, 45(11): 998-1019. doi: 10.2747/0020-6814.45.11.998
Lai, S. C., Yi, H. S., Lin, J. H., 2006. Granulite xenoliths in Cenozoic volcanic rocks of North Qiang tang, Tibetan plateau, and their geological significance. Acta Petrologica et Mineralogica, 25(5): 423-432 (in Chinese with English abstract).
Lai, S. C., Yi, H. S., Liu, C. Y., et al., 2002. Trace element geochemistry and classification of amphiboles of the Cenozoic high-potassium calc-alkaline volcanic rock series from North Qiang tang, Qing hai-Tibetan plateau. Acta Petrologica Sinica, 18(1): 17-24 (in Chinese with English abstract).
Li, G. M., 2000. Pezrologic features and genesis of Cenozoic volcanic rocks, Qiang tang area, northern Tibetan plateau. Geology Geochemistry, 28(2): 38-44 (in Chinese with English abstract).
Li, Y. G., Mo, X. X., Yi, H. S., et al., 2005. Research on the Cenozoic volcanic rocks in the Cuoli area of Qiangtang. J. Mineral Petrol, 25(2): 27-34 (in Chinese with English abstract).
Lin, J. H., Yi, H. S., Shi, Z. Q., et al., 2004. Study on isotopic geochemistry of Cenozoic high-Kcal-alkaline volcanic rocks in the Zuerkang Ulamountain area, northern Tibetan. J. Mineral Petrol, 24(4): 59-64(in Chinese with English abstract).
Lin, J. H., Yi, H. S., Zhao, B., et al., 2003. ⁴⁰Ar-³⁹Ar isotopic dating and its implication of Cenozoic volcanic rocks from Zuerkang Ula mountain area, northern Tibetan. J. Mineral Petrol., 23(3): 31-34 (in Chinese with English abstract).
Mo, X. X., Deng, J. F., Dong, F. L., et al., 2001. Volcanic petrotectonic assemblages in Sanjiang orogenic belt, SW China and implication for tectonics. Geological Journal of China Universities, 7(2): 121-138 (in Chinese with English abstract).
Mo, X. X., Dong, G. C., Zhao, Z. D., et al., 2005. Spatial and temporal distribution and characteristics of granitoids in the Gangdese, Tibet and implication for crustal growth and evolution. Geological Journal of China Universities, 11(3): 281-290 (in Chinese with English abstract).
Pan, G. T., Ding, J., 2004. The geological map of the Qinghai-Xizang (Tibet) Plateau and adjacent areas, 1 ∶1 500 000. Chengdu Cartographic Publishing House, Chengdu (in Chinese).
Prouteau, G., Scaillet, B., Pichav ant, M., et al., 2001. Evidence for mantle metaso matism by hydrous silicic melts derived from subducted oceanic rust. Nature, 410 : 197-200. doi: 10.1038/35065583
Tan, F. W., Pan, G. T., Xu, Q., 2000. The uplift of Qianghai-Xizang plateau and geochemical characteristics of cenozoic volcanic rocks from the center of Qiang tang, Xizang. Acta Petrologica et Mineralogica, 19(2): 121-130 (in Chinese with English abstract).
Wei, J. Q., Wang, J. X., Niu, Z. J., 2004. The Cenozoic volcanic rocks from the Chibuzhang lake area in the Qiangtang area. Sedimentary Geology and Tethyan Geology, 24(2): 16-21 (in Chinese with English abstract).
Wei, J. Q., Yao, H. Z., Niu, Z. J., et al., 2005. Identification of the adakitic rock association in Chibuzhang Co. area, northern Tibet, and its significance. Acta Petrologica et Mineralogica, 24(3): 173-178 (in Chinese with English abstract).
Wei, W. B., Jin, S., Ye, G. F., 2006. Features of the faults in center and North Tibetan plateau: Based on results of Indepth (Ⅲ)-M T. Earth Science—Journal of China University of Geosciences, 31(2): 257-265 (in Chinese with English abstract).
Xiong, X., Wang, J. Y., Teng, J. W., 2007. Deep mechanical background for the cenozoic volcanism in the Tibetan Plateau. Earth Science—Journal of China University of Geosciences, 32(1): 1-6 (in Chinese with English abstract).
Xu, J. F., Wang, Q., 2003. Tracing the thickening process of continental crust through studing adakitic rocks : Evidence from volcanic rocks in the North Tibet. Earth Science Frontiers, 10(4): 401-406 (in Chinese with English abstract).
Xu, Z. Q., Yang, J. S., Li, H. B., et al., 2006. The Qinghai Tibet plateau and continental dynamics : Areview on terrain tectonics, collisional orogensis, and processes and mechanisms for the rise of the plateau. Geology in China, 33(2): 221-238 (in Chinese with English abstract).
Yogodzinski, G. M., Lees, J. M., Churikova, T. G., et al., 2001. Geochemical evidence for the melting of subducting oceanic lithosphere at plates edges. Nature, 409 : 500-504. doi: 10.1038/35054039
Zhang, Q., Wang, Y., Liu, H. T., et al., 2003. On the spacetime distribution and geody namic environments of adakites in China. Earth Science Fronties, 10(4): 385-400 (in Chinese with English abstract).
Zhang, Q., Xu, J. F., Wang, Y., et al. ., 2004. Diver sity of adakite. Geological Bulletin of China, 23(9-10): 959-965 (in Chinese with English abstract).
Zhang, Y. F., Deng, J. K., 1994. Anintro duction to the geological evolution of Hoh Xil and its adjacent region, Seismological Press, Beijing, 1-177 (in Chinese).
卜建军, 段其发, 2006. 藏北赤布张错南部帮麦锑金矿点的地质特征及意义. 地质通报, 25(1-2): 273-276. https://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD2006Z1043.htm
Castillo, P. R., 2006. 埃达克岩成因的回顾. 科学通报, 51 (6): 617-627. doi: 10.3321/j.issn:0023-074X.2006.06.001
迟效国, 李才, 金巍, 等, 1999. 藏北新生代火山作用的时空演化与高原隆升. 地质论评, 45(增刊): 978-986. https://www.cnki.com.cn/Article/CJFDTOTAL-DZLP1999S1144.htm
邓万明, 1998. 青藏高原北部新生代板内火山岩. 北京: 地质出版社, 1-168.
赖绍聪, 2003. 青藏高原新生代埃达克质岩的厘定及其意义. 地学前缘, 10(4): 407-415. doi: 10.3321/j.issn:1005-2321.2003.04.009
赖绍聪, 刘池阳, 2001. 青藏高原北羌塘榴辉岩质下地壳及富集型地幔源区. 岩石学报, 17(3): 459-468. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200103014.htm
赖绍聪, 刘池阳, O′Reilly, S. Y., 2001. 北羌塘新第三纪高钾钙碱火山岩系的成因及其大陆动力学意义. 中国科学(D辑), 31(s1): 34-42. https://www.cnki.com.cn/Article/CJFDTOTAL-JDXK2001S1005.htm
赖绍聪, 伊海生, 林金辉, 2006. 青藏高原北羌塘新生代火山岩中的麻粒岩中的捕掳体. 岩石矿物学杂志, 25(5): 423-432. doi: 10.3969/j.issn.1000-6524.2006.05.006
赖绍聪, 伊海生, 刘池阳, 等, 2002. 青藏高原北羌塘新生代高钾钙碱岩系火山岩角闪石类型及痕量元素地球化学, 岩石学报, 18(1): 17-24. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200201002.htm
李光明, 2000. 藏北羌塘地区新生代火山岩岩石特征及其成因探讨. 地质地球化学, 28(2): 38-44. doi: 10.3969/j.issn.1672-9250.2000.02.006
李佑国, 莫宣学, 伊海生, 等, 2005. 羌塘错尼地区新生代火山岩研究. 矿物岩石, 25(2): 27-34. doi: 10.3969/j.issn.1001-6872.2005.02.006
林金辉, 伊海生, 时志强, 等, 2004. 藏北祖尔肯乌拉山地区新生代高钾钙碱岩系火山岩同位素地球化学研究. 矿物岩石, 24(4): 59-64. doi: 10.3969/j.issn.1001-6872.2004.04.011
林金辉, 伊海生, 赵兵, 等, 2003. 藏北祖尔肯乌拉山地区新生代火山岩⁴⁰Ar-³⁹Ar同位素定年及其意义. 矿物岩石, 23 (3): 31-34. doi: 10.3969/j.issn.1001-6872.2003.03.008
莫宣学, 邓晋福, 董方浏, 等, 2001. 西南三江造山带火山岩-构造组合及其意义. 高校地质学报, 7(2): 121-138. doi: 10.3969/j.issn.1006-7493.2001.02.001
莫宣学, 董国臣, 赵志丹, 等, 2005. 西藏冈底斯带花岗岩的时空分布特征及地壳生长演化信息. 高校地质学报, 11 (3): 281-290. doi: 10.3969/j.issn.1006-7493.2005.03.001
潘桂棠, 丁俊, 2004. 青藏高原及邻区地质图, 1 ∶1 500 000. 成都: 成都地图出版社.
谭富文, 潘桂棠, 徐强, 2000. 羌塘腹地新生代火山岩的地球化学特征与青藏高原隆升. 岩石矿物学杂志, 19(2): 121-130. doi: 10.3969/j.issn.1000-6524.2000.02.004
魏君奇, 王建雄, 牛志军, 2004. 羌塘赤布张错地区新生代火山岩研究. 沉积与特提斯地质, 24(2): 16-21. doi: 10.3969/j.issn.1009-3850.2004.02.003
魏君奇, 姚华舟, 牛志军, 等, 2005. 藏北赤布张错地区埃达克岩的厘定及其意义. 岩石矿物学杂志, 24(3): 173-178. doi: 10.3969/j.issn.1000-6524.2005.03.002
魏文博, 金胜, 叶高峰, 等, 2006. 西藏高原中、北部断裂构造特征: Indepth(Ⅲ)-M T观测提供的依据. 地球科学———中国地质大学学报, 31(2): 257-265. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX200602016.htm
熊熊, 王继业, 腾吉文, 2007. 青藏高原新生代火山活动的深部力学背景. 地球科学———中国地质大学学报, 32(1): 1-6. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX200701000.htm
许继峰, 王强, 2003. Adakitic火山岩对大陆地壳增厚过程的指示: 以青藏北部火山岩为例. 地学前缘, 10(4): 401-406. doi: 10.3321/j.issn:1005-2321.2003.04.008
许志琴, 杨经绥, 李海兵, 等, 2006. 青藏高原与大陆动力学—地体拼合、碰撞造山及高原隆升的深部驱动力. 中国地质, 33(2): 221-238. https://www.cnki.com.cn/Article/CJFDTOTAL-DIZI200602001.htm
张旗, 王焰, 刘红涛, 等, 2003. 中国埃达克岩的时空分布及其形成背景. 地学前缘, 10(4): 385-400. doi: 10.3321/j.issn:1005-2321.2003.04.007
张旗, 许继峰, 王焰, 等, 2004. 埃达克岩的多样性. 地质通报, 23(9-10): 959-965. https://www.cnki.com.cn/Article/CJFDTOTAL-ZQYD2004Z2019.htm
张以弗, 邓建康, 1994. 青海可可西里及临区地质概论. 北京: 地震出版社, 1-177.