Geochemical Characteristics and Tectonic Significance of Kunlunguan A-Type Granite, Guangxi
-
摘要: 昆仑关岩体位于广西南丹-昆仑关燕山期花岗岩带西南端, 岩石类型为黑云母花岗岩.岩相学及化学成分显示其属高钾钙碱性岩系, 具高硅、富碱和铝、低磷和钛的特点, SiO2含量为68.13~72.61, K2O/Na2O比值介于1.28~1.69之间, 铝指数A/CNK=0.72~1.28, 属准铝质一强过铝质岩石.富集Ga、Rb、Th、U、Pb等元素, 而强烈亏损13a、Nb、Sr、P和Ti.稀土元素具明显负Eu异常, 总体呈现轻稀土富集的右倾"V"形配分模式.昆仑关古民单元锆石LA-ICP-MSU-Pb定年结果为93±1Ma, 形成于晚白垩世.矿物组成及地球化学特征确定了南丹-昆仑关花岗岩带是华南西南端一条重要的铝质A型花岗岩带, 控岩断裂构造为NW向南丹一昆仑关深大断裂.岩石学及主量和微量元素(含稀土)特征表明岩体侵位于后碰撞阶段的张性构造环境.结合研究范围在晚白垩世的构造背景及区域应力场匹配组合关系, 认为其与印度板块在该时期北移所引起的古太平洋板块高角度俯冲所导致的弧后拉张有关, 与浙闽沿海A型花岗岩或碱性岩分别代表了匹配构造体制下的两条A型花岗岩带.Abstract: Kunlunguan pluton, located in the southwest part of the Nandan-Kunlunguan granite belt, Guangxi, is mainly composed of biotite granite. Petrography and chemical compositions show that it belongs to high-K calc-alkaline series characterized by high silicon, is enriched in alkali and aluminum but depleted in phosphorus and titanium. Its SiO2 contents range from 68. 13% to 72. 61%, while K2O/Na2O ratios and A/CNK values vary from 1.28 to 1.69 and 0. 72 to 1.28 respectively, ascribed to a suite of met aluminous to intensively peraluminous rock. Ga, Rb, Th, U and Pb elements are enriched in the intrusion while Ba, Nb, Sr, P and Ti depleted. REE is characterized by obvious negative anomalies with Eu/Eu* 0. 53-0. 73 and exhibits right-dipping "V" patterns with LREE enrichment. LA-ICP-MS zircon U-Pb dating yields a weighted mean 206pb/238U age of 93±1 Ma (MSDW=1. 7) for the Gumin unit of the pluton, implying its Late Cretaceous intrusion time. Mineralogy and geochemistry confirm that the Nandan-Kuntunguan granite belt is an important aluminous A-type granite belt in the South China, controlled by northwestward Nandan-Kunlunguan deep fault. Petrology, major and trace el- ement features display that the pluton intruded in a post-collisional extensive tectonic setting. These results, combined with Late Cretaceous tectonic environment and regional stress field matching relationship in the studied area, indicate the A-type granite action is due to back-arc extension related to high angle subduction of the ancient Pacific plate which is caused by Indian plate northward movement. This granite belt and those granite or alkaline rocks in the coastal areas of Zhejiang-Fujian provinces represent the two A-type granite belts under a matching tectonic system.
-
Key words:
- A-type granite /
- LA-ICP-MS zircon U-Pb dating /
- post-collision /
- Indian plate /
- Damingshan /
- South China
-
图 1 西南丹一昆仑关地区大地构造位置图(a)、广西构造略图(b)及昆仑关岩体地质图(c)
底图分别据王强等(2005)、广西壮族自治区区域地质测量队(1972)以及广西有色金属地质研究所(1993)改编.也图中断裂编号依次为：①政和--大埔断裂；②福安一南靖断裂；③长乐--南澳断裂；④南丹--昆仑关断裂.b.图中斜矩形示南丹--昆仑关铝质A型花岗岩带.a奥陶系及白垩系地层位于图幅外.1.第四系；2.第三系；3.三叠系；4.二叠系；5.石炭系；6.泥盆系；7.寒武系；8.晚白垩世A型花岗岩或碱性岩；9. 晚白垩世断陷盆地
Fig. 1. Sketch maps showing tectonic location of Nandan-Kunlunguan belt, Guangxi(a), simplified tectonic of Guangxi(b), and geological character of Kunlunguan intrusion(c)
图 2 仑关岩体的全碱--SiO2(即TAS)岩石分类图解(a)和K2O-SiO2图解(b)
碱性与亚碱性系列划分曲线据Irvine and Baragar(1971)；岩系划分据Peccerillo and Taylor(1976)；南丹地区大厂(6个样品)和芒场(2个样品)矿田同时代黑云母花岗岩阴影投影范围据蔡明海等(2004)确定
Fig. 2. TAS classification(a) and K2O-SiO2 diagram(b)of Kunlunguan intrusion
图 3 仑关岩体原始地幔标准化微量元素蛛网图(a)及球粒陨石标准化稀土配分曲线(b)
原始地幔和球粒陨石标准据Sun and McDonough(1989)；浙闽沿海晚白垩世铝质A型花岗岩椐邱检生等(1999, 2000)，共11个样品点；图例同图 2。下同
Fig. 3. Pnmitive mantle normalized trace element distributions(a) and chondfite normalized REE patterns(b)
图 4 仑关岩体A型花岗岩判别图解
S、I、M与A型花岗岩划分据Whalen et al.(1987)；南丹地区大厂(4个样品)和芒场(4个样品)矿田花岗岩数据据蔡明海等(2004)
Fig. 4. A-type granite discrimination diagram of Kunlunguan intrusion
图 5 古民黑云母花岗岩(NY-3-10)中锆石形态阴极发光(CL)图像
圆圈及圈中(外)数字分别表示分析点位和测点编号，圈外年龄示206Pb/238U表面年龄
Fig. 5. Cathodo luminescena images showing typical zircon morphology of Gumin biotite granite (NY-3-10)
图 6 民黑云母花岗岩(NY-3-10)锆石LA-ICP-MS U-Pb年龄谐和图
加权平均年龄为去掉7.9、14和16号测点(图中阴影分析点)外12粒岩浆锆石的加权结果
Fig. 6. Coneordia plots for zircons from Gumin biotite granite
图 7 昆仑关岩体的Rb/30-Hf-3Ta判别图解
Fig. 7. Rb/30-Hf-3Ta discrimination plot of Kunlunguan intrusion
图 8 仑关岩体的R1-104Ga/Al(a)和Nb-Y-Ce(b)图解
Fig. 8. R1-104Ga/AI(a) and Nb-Y-Ce(b)diagrams of Kunlunguan intrusion
表 1 仑关岩体主量元素(%)和微量元素(10-6)分析结果
Table 1. Major and trace element compositions of Kunlunguan intrusion
表 2 昆仑关岩体古民单元(NY-3-10)LA-ICP-MS错石UPb分析结果
Table 2. LA-ICP-MS zircon U-Pb dating data for Gumin unit(NY-3-10), Kunlunguan intrusion
表 3 昆仑关岩体古民单元(NY-3-10)错石稀土元素分析结果
Table 3. Zircon trace element compositions for Gumin unit(NY-3-10), Kunlunguan intrusion
-
[1] Andersen, T., 2002. Correction of comnlon lead in U-Pb armlyses that do not report 204Pb. Chem. Geol. , 192: 59-79. doi: 10.1016/S0009-2541(02)00195-X [2] Beck, R. A., Burbank, D. W., Sercombe, W. J., et al., 1995. Stratigraphic evidence for an early collision between northwest India and Asia. Nature, 373: 55-58. doi: 10.1038/373055a0 [3] Cai, M. H., He, L. Q., Liu, G. Q., et al., 2006. SHRIMP zircon U-Pb dating of the intrusive rocks in the Dachang tin-polymet allic ore field, Guangxi and their geological significance. Geological Review, 52(3): 409-414(in Chinese with English abstract). [4] Cai, M. H., Liang, T., Wu, D. C., 2005. Geological characteristics and ore-forming time of the Kangrna deposit in the Dachang tin-polymet allic ore field, Guangxi. Acta Geologica Sinica, 79(2): 262-268(in Chinese with English abstract). [5] Cai, M. H., Liang, T., Wu, D. C., et al., 2004. Geochemical characteristics of granites and its structural genetic ellvironment in the Nandan-Hechi met allogenic belt. northwest Guangxi. Geotectonica et Met allogenia, 28 (3): 306-313(in Chinese with English abstract). [6] Chen, D. L., Sun, Y., Liu, L., et al., 2007. In situ LA-ICP-MS zircon U-Pb age of ultrahigh-pressure eclogites in the Yukahe area, northern Qaidam basin. Science in China (Ser. D), 50(Suppl): 322-330. [7] Chen, H. D., Zeng, Y. F., Li, X. Q., 1989. Evolution of the sedimentation and tectonics of Late Paleozoic Danchi basin. Acta Sedimentologica Sinica, 7(4): 85-96(in Chinese with English abstract). [8] Chen, P. R., Hua, R.M., Zhang, B. T., et al., 2002. Early Yanshanian post-orogenic granitoids in the Nanling region-Petrological constraints and geodynamic settings. Science in China (Ser. D), 32(8): 755-768. [9] Chen, Z. Z., Peng, G. Y., Oiu, S. P., et al., 1986. Genetic study of the Damingshan tungsten deposit, Guangxi. Geology and Prospecting, 5: 13-19(in Chinese). [10] Cui, B., Zhai, Y. S., Meng, Y. F., et al., 2000. Au-Ag oreforming system in Dayaoshan-Xidamingsban, Guangxi, China. Earth Science-Journal of China University of Geosciences, 25(4): 352-355(in Chinese with English abstract). [11] Ding, X., Chen, P. R., Chen, W. F., et al., 2006. Single zircon LA-ICPMS U-Pb dating of Weishan granite (Hunan, South China) and its petrogenetic significance. Science in China(Set. D), 49(8): 816-827. doi: 10.1007/s11430-006-0816-4 [12] Eby, G. N., 1992. Chemical subdivision of the A-type granitoids: Petrogenetic and tectonic implications. Geology, 20: 641-644. [13] Flower, M. F. J., Tamaki, K., Hoang, N., 1998. Mantle extrusion: A model for dispersed volcanism and DUPA-like asthenosphere in east Asia and the western Pacific. In: Flower, M. F. J., Chung, S. L., Lo, C. H., et al., eds., Mantle dynamics and plate interactions in East Asia. Geodynamics, 27: 67-88. [14] Geng, H. Y., Xu, X.S., O'Reilly, S. Y., et al., 2006. Cretaceous volcanic-intrusive magmatism in western Guangdong and its geological significance. Science in China (Ser. D), 49(7): 696-713. doi: 10.1007/s11430-006-0696-7 [15] Gilder, S.A., Gill, J., Coe, R.S., et al., 1996. Isotopic and paleomagnetic constraints on the Mesozoic tectonic evolution of South China. Journal of Geophysical Research, 101: 16137-16154. doi: 10.1029/96JB00662 [16] Gilder, S. A., Leloup, P. H., Courtillot, V., et al., 1999. Tectonic evolution of the Tancheng-Lujiang (Tan-Lu) fault via Middle Triassic to Early Cenozoic paleomagnetic data. Journal of Geophysical Research, 104(B7): 15365-15390. doi: 10.1029/1999JB900123 [17] Griffin, W. L., Belousova, E. A., Shee, S., 2004. Crustal evolution in the northern Yilam eraton: U-Pb and Hf isotope evidence from detrital zircons. Precambrian Research, 131(3-4): 231-282. doi: 10.1016/j.precamres.2003.12.011 [18] Harris, H. B. W., Pearce, J. A., Tindle, A. G., 1986. Geochemical characteristics of collision-zone magmatism. In: Coward。M. P., Reis, A. G., eds., Collision tectonics. Spec. PubZ. Grol. Soc. Lond., 19: 67-81. [19] Hong, D. W., Wang, S. G., Han, B. F., et al., 1995. Tectonic classification and discrimination criteria for alkaline granites. Sciencein China (Set. B), 25(4): 418-426 (in Chinese). [20] Hoskin, P. W. Q., Black, L. P., 2000. Metamorphic zircon formation by solid-state recrystallization of protolith igneous zircon. J. Metamorph. Geol. , 8: 423-439. [21] Hu, J., Qiu, J. S., Wang, D. Z., et al., 2005. Comparative investigations of A-type granites in the coastal and the Nanling inland areas of SE China, and their tectonic significances. Geological Journal of China Universities, 11(3): 404-414(in Chinese with English abstract). [22] Irvine, T. N., Baragar, W. R. A., 1971. A guide to the chemical classification of comnlon volcanic rocks. Can. J. Earth Sci. , 8(4): 523-548. [23] Jaeger, J. J., Courtillot, V., Tapponnier, P., 1989. Paleontological view of the ages of the Deccan traps, the Cretaeeous/Tertiary boundary, and the India-Asia collision. Geology, 17: 316-319. [24] Lapierre, H., Jahn, B. M., Charvet, J., et al., 1997. Mesozoic felsic arc magmatism and continental olivime tholeiites in Zhejiang Province and their relationship with the teetonic activity in southeastern China. Tectonophysics, 274(4): 321-338. doi: 10.1016/S0040-1951(97)00009-7 [25] Li, S. R., Wei, J. H., Deng, J., et al., 2007. Ore types of tungsten poly-met allic deposits and prospecting indications. China Tungsten Industry, 22(6): 19-24(in Chinese with English abstract). [26] Li, X. H., Li, W. X., Li, Z. X., 2007. On the genetic classification and tectonic implications of the Early Yanshanian granitoids in the Nanling range, South China. Chinese Science Bulletin, 52(14): 1873-1885. doi: 10.1007/s11434-007-0259-0 [27] Liu, B. M., Xia, B., Li, X. X., et al., 2006. Southeastern extension of the Red River fault zone (RRFZ) and its teetonic evolution significance in western South China Sea. Science in China (Ser. D), 49(8): 839-850. doi: 10.1007/s11430-006-0839-x [28] Martin, H., Bonin, B., Capdevila, R., et al., 1994. The Kuiqi peralkaline granitic complex(SE China): Petrology and geochemistry. J. Petrol. , 35: 983-1015. doi: 10.1093/petrology/35.4.983 [29] Maruyama, S., Seno, T., 1986. Orogeny and relative plate motions: Example of the Japanese islands. Tectonophysics, 127: 305-329. doi: 10.1016/0040-1951(86)90067-3 [30] Middlemost, E. A. K., 1994. Naming materials in the maw ma/igneous rock system. Earth-Sci. Rev. , 37: 215-224. doi: 10.1016/0012-8252(94)90029-9 [31] Peccerillo, A., Taylor, S.R., 1976. Geochemistry of Eocene calc-alkaline volcanic rocks of the Kastamonu area, northern Turkey. Contrib. Mineral. Petrol. , 58: 63-81 doi: 10.1007/BF00384745 [32] Qiu, J. S., Wang, D.Z., Mclnnes, B.I.A., 1999. Geochemistry and petrogenesis of the I and A type composite granite masses in the coastal area of Zhejiang and Fujian Provinces. Acta Petrologica Sinica, 15(2): 237-246 (in Chinese with English abstract). [33] Qiu, J. S., Wang, D. Z., Satoshi, K., et al., 2000. Geochemistry and petrogenesis of aluminous A-type granites in the coastal area of Fuiian Province. Geochimica, 29(4): 313-321(in Chinese with English abstract). [34] Ren, J. Y., Tamaki, K., Li, S. T., et al., 2002. Late Mesozoic and Cenozoic rifting and its dynamic setting in eastern China and adjacent areas. Tectonophysics, 344: 175-205. doi: 10.1016/S0040-1951(01)00271-2 [35] Shu, L. S., Zhou, X. M., 2002. Late Mesozoic teetonism of Southeast China. Geological Review, 48(3): 249-260 (in Chinese with English abstract). [36] Sun, S. S., McDonough, W. F., 1989. Chemical and isotopic systematics of oceanic basalts: Implications for mantle composition and processes. In: Saunders, A.D., Norry, M J., eds., Magmatism in the ocean basins. Geol. Soc. Spec. Pub., 42: 313-345. [37] Sun, Z., Zhong, Z. H., Zhou, D., 2007. The analysis and anslogue modeling of the tectonic evolution and strong subsidence in the Yinggehai basin. Earth Science-Journal of China University of Geosciences, 32(3): 347-356 (in Chinese with English abstract). [38] Tatsumi, Y., Maruyama, S., Nodha, S., 1990. Mechanism of backarc opening in the Japan Sea: Role of asthenospheric iniection. Tectonophysics, 181: 299-306. doi: 10.1016/0040-1951(90)90023-2 [39] Wan, T. F., 2004. Tectonics of Chilla. Geological Publishing House, Beijing, 152-162(in Chinese). [40] Wang, Q., Zhao, Z.H., Jian, P., et al., 2005. GeochronolcIgY of Cretaceous A-type granitoids or alkaline intrusive rocks in the hinterland, South China: Constraints for Late-Mesozoic tectonic evolution. Acta Petrologica Sinica, 21(3): 795-808(in Chinese with English abstract). [41] Wang, D. H., Chen, Z. C., Chen, W., et al., 2004. Dating the Dachang giant tin-polymet allic deposit in Nandan, Guangxi. Acta Geologica Sinica, 78(1): 132-138(in Chinese with English abstract). [42] Wang, D. Z., Zhao, G. T., Qiu, J. S., 1995. The tectonic constraint on the Late Mesozoic A-type granitoids in eastem China. Geological Journal of China Universities, 1(2): 13-21(in Chinese with English abstract). [43] Whalen, J. B., Currie, K. L., Chappell, B. W., 1987. A-type granites: Geochemical characteristics, discriminatuon and petrogenesis. Contrib. Mineral. Petrol., 95: 407-419. doi: 10.1007/BF00402202 [44] Wu, C. L., Zhou, X. R., Huang, X. C., et al., 1998. A-type granites in Maotan, Anhui. Acta Geologica Sinica, 72(3): 237-248(in Chinese with English abstract). [45] 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 [46] Wu, G. G., Zhang, D., Chen, B. L., et al., 2000. Transformation of Mesozoic tectonic domain and its relation to mineralization in southwastem China: An evidence of southwestern Fuiian Province. Earth Science-Journal of China University of Geosciences, 25(4): 390-396(in Chinese with English abstract). [47] Xiang, H. F., Wang, J. L., Han, Z. J., et al., 2007. Geological analysis and FT dating of the large-scale right-lateral strike-slip movement of the Red River fault zone. Scielce in China(Set. D), 50(3): 331-342. doi: 10.1007/s11430-007-2037-x [48] Yuan, H. L., Gao, S., Liu, X. M., et al., 2004. Accurate U-Pb age and trace element determinations of zircon by laser ablation-inductively coupled plasma mass spectrometry. Geosand. Newsl., 28: 353-370. doi: 10.1111/j.1751-908X.2004.tb00755.x [49] Zhou, X. M., Li, W. X., 2000. Origin of Late Mesozoic igneOUS rocks of southeastem China: Implications for Iithosphere subduction and underplating of mafic magma. Tectonophysics, 326: 269-287. doi: 10.1016/S0040-1951(00)00120-7 [50] 蔡明海, 何龙清, 刘国庆, 等, 2006. 广西大厂锡矿田侵入岩SHRIMP锆石U-Pb年龄及其意义. 地质论评, 52(3): 409-414. doi: 10.3321/j.issn:0371-5736.2006.03.023 [51] 蔡明海, 梁婷, 吴德成, 2005. 广西大厂锡多金属矿田亢马矿床地质特征及成矿时代. 地质学报, 79(2): 262-268. doi: 10.3321/j.issn:0001-5717.2005.02.012 [52] 蔡明海, 梁婷, 吴德成, 等, 2004. 桂西北丹池成矿带花岗岩地球化学特征及其构造环境. 大地构造与成矿学, 28(3): 306-313. doi: 10.3969/j.issn.1001-1552.2004.03.011 [53] 陈洪德, 曾允孚, 李孝全, 1989. 丹池晚古生代盆地的沉积和构造演化. 沉积学报, 7(4): 85-96. https://www.cnki.com.cn/Article/CJFDTOTAL-CJXB198904006.htm [54] 陈志中, 彭根永, 邱少平, 等, 1986. 广西大明山钨矿床的成因研究. 地质与勘探, 5: 13-19. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKT198605002.htm [55] 崔彬, 翟裕生, 蒙义峰, 等, 2000. 广西大瑶山一西大明山金银成矿系统研究. 地球科学-中国地质大学学报, 25(4): 352-355. doi: 10.3321/j.issn:1000-2383.2000.04.004 [56] 洪大卫, 王式洗, 韩宝福, 等, 1995. 碱性花岗岩的构造环境分类及其鉴别标志. 中国科学(B辑), 25(4): 418-426. https://www.cnki.com.cn/Article/CJFDTOTAL-JBXK199504012.htm [57] 胡建, 邱检生, 王德滋, 等, 2005. 中国东南沿海与南岭内陆A型花岗岩的对比及其构造意义. 高校地质学报, 11(3): 404-414. doi: 10.3969/j.issn.1006-7493.2005.03.011 [58] 李水如, 魏俊浩, 邓军, 等, 2007. 广西大明山矿集区钨多金属矿床类型及控矿因素与找矿标志. 中国钨业, 22(6): 19-24. doi: 10.3969/j.issn.1009-0622.2007.06.005 [59] 邱检生, 王德滋, Mclnnes, B.L.A., 1999. 浙闽沿海地区I型一A型复合花岗岩体的地球化学及成因. 岩石学报, 15(2): 237-246. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB902.009.htm [60] 邱检生, 王德滋, 蟹泽聪史, 等, 2000. 福建沿海铝质A型花岗岩的地球化学及岩石成因. 地球化学, 29(4): 313-321. https://www.cnki.com.cn/Article/CJFDTOTAL-DQHX200004000.htm [61] 舒良树, 周新民, 2002. 中国东南部晚中生代构造作用. 地质论评. 48(3): 249-260. doi: 10.3321/j.issn:0371-5736.2002.03.004 [62] 孙珍, 钟志洪, 周蒂, 2007. 莺歌海盆地构造演化与强烈沉降机制的分析和模拟. 地球科学-中国地质大学学报, 32(3): 347-356. doi: 10.3321/j.issn:1000-2383.2007.03.007 [63] 万天丰, 2004. 中国大地构造学纲要. 北京: 地质出版社, 152-162. [64] 王德滋, 赵广涛, 邱检生, 1995. 中国东部晚中生代A型花岗岩的构造制约. 高校地质学报, 1(2): 13-21. https://www.cnki.com.cn/Article/CJFDTOTAL-GXDX502.001.htm [65] 王登红, 陈毓川, 陈文, 等, 2004. 广西南丹大厂超大型锡多金属矿床的成矿时代. 地质学报, 78(1): 132-138. doi: 10.3321/j.issn:0001-5717.2004.01.015 [66] 王强, 赵振华, 简平, 等, 2005. 华南腹地白垩纪A型花岗岩类或碱性侵入岩年代学及其对华南晚中生代构造演化的制约. 岩石学报, 21(3): 795-808. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200503020.htm [67] 吴才来, 周瑚若, 黄许陈, 等, 1998. 安徽茅坦A型花岗岩研究. 地质学报, 72(3): 237-248. doi: 10.3321/j.issn:0001-5717.1998.03.005 [68] 吴淦国, 张达, 陈柏林, 等, 2000. 中国东南大陆中生代构造域的转换及其与成矿的关系-以闽西南地区为例. 地球科学-中国地质大学学报, 25(4): 390-396. doi: 10.3321/j.issn:1000-2383.2000.04.011 -
下载:
点击查看大图
图(8) / 表(3)
计量
- 文章访问数: 3703
- HTML全文浏览量: 105
- PDF下载量: 69
- 被引次数: 0
