Geochronology, Hf Isotope, Geochemistry and Petrogenesis of the Baimashan Granitic Complex in the Central Hunan Province
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摘要: 为深入探讨华南早古生代和早中生代的构造演化、岩浆活动及其资源成矿效应，对湘中地区白马山复式岩体进行了系统的野外调查，并开展了锆石年代学、Hf同位素及地球化学研究. 锆石LA-ICP-MS U-Pb年龄分析结果显示，白马山岩体水车超单元糜棱岩化花岗岩和龙潭-小沙江超单元黑云母花岗闪长岩的加权平均年龄分别为409±2 Ma和211±1 Ma，二者分别为加里东晚期和印支晚期岩浆活动的产物. 加里东期糜棱岩化花岗岩具有高硅、高碱和强过铝质的特征，表现出强烈的负Eu异常，结合其富集的Hf同位素组成[εHf（t）=-13.4~-5.4]，可推测其应为古元古代沉积岩的部分熔融产生的S型花岗岩. 印支期黑云母花岗闪长岩则具有低硅、高碱和准铝质的特征，显示出中等强度的负Eu异常，且其εHf（t）值（-10.3~-7.4）较负、模式年龄古老（1.71~1.89 Ga），为古元古代变火成岩与部分变沉积岩重熔形成的Ⅰ型花岗岩. 白马山复式岩体的加里东期和印支期超单元可能均形成于陆内造山的构造环境中. 加里东期岩体与区域W矿化之间、印支期岩体与区内Au-Sb-W矿化之间分别具有密切的成因联系，表明这些岩体具有良好的Au-Sb-W成矿潜力.Abstract: In order to thoroughly investigate the tectonic evolution, magmatic activities, and their effects on mineral resource formation during the Early Paleozoic and Early Mesozoic eras in South China, systematic field investigations were conducted in the Baimashan complex located in the central Hunan region. Additionally, zircon geochronological analysis, Hf isotope studies, and geochemical assessments were performed. Zircon LA-ICP-MS U-Pb dating illustrates that the weighted mean ages of the Shuiche mylonitized granite and the Longtan-Xiaoshajiang biotite granodiorite within the Baimashan granitic complex are 409±2 Ma and 211±1 Ma, respectively. These ages correspond to the Late Caledonian and Indosinian magmatic events, respectively. The Caledonian mylonitized granite is characterized by high silica, high alkali and strong peraluminosity, accompanied by a pronounced negative Eu anomaly. This, combined with its enriched Hf isotopic composition [εHf(t)=-13.4 to -5.4], indicates that it is likely a S-type granite formed through partial melting of Paleoproterozoic sedimentary rocks. In contrast, the Indosinian biotite granodiorite exhibits low-silica, high-alkalinity and aluminous, displaying a moderate Eu-negative anomaly with a relatively negative εHf(t) value (-10.3 to -7.4) and an ancient modal age (1.71 to 1.89 Ga). This granodiorite can be categorised as a Paleoproterozoic meta-igneous mixing of partially metasomatised sedimentary rocks remelted to form Ⅰ type granites. The Caledonian and Indosinian superunits of the Baimashan complex may have been formed in a tectonic environment of intra-plate orogeny. There is a strong genetic connection between the Caledonian rocks and the regional W mineralization, as well as between the Indosinian granitic rocks and the Au-Sb-W mineralization in the area. These rocks exhibit significant potential for Au-Sb-W mineralization.
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Key words:
- Baimashan granitic complex /
- geochronology /
- Hf isotopes /
- geochemistry /
- Petrogenesis
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图 1 （a）华南早古生代和早中生代花岗岩分布图；（b）白马山岩体地质图
图a据Song et al.（2015）；图b修改据张义平等（2015）
Fig. 1. (a) Distribution of the Early Paleozoic and Early Mesozoic granites in South China; (b) Geological map of the Baimashan granitic complex
图 2 白马山复式岩体岩相学特征
糜棱岩化花岗岩手标本（a）、单偏光（b）和正交偏光图像（c）；黑云母花岗闪长岩手标本（d）、单偏光（e）和正交偏光图像（f）；Bt. 黑云母；Hbl. 角闪石；Kfs. 钾长石；Pl. 斜长石；Qz. 石英
Fig. 2. Petrographic characteristics of the Baimashan granitic complex
图 3 白马山复式岩体锆石U-Pb年龄谐和图
a. 糜棱岩化花岗岩；b. 黑云母花岗闪长岩
Fig. 3. U-Pb concordia diagrams of zircons from the Baimashan granitic complex
图 4 白马山复式岩体岩石分类图解
a.（Na2O+K2O）-SiO2图解（La Bas et al.，1986）；b. A/NK-A/CNK图解；c. K2O-SiO2图解；d.（Na2O+K2O）/CaO-（Zr+Nb+Ce+Y）图解（Whalen et al.，1987）
Fig. 4. Classification of the Baimashan granitic complex on the basis diagrams
图 5 白马山复式岩体球粒陨石标准化稀土元素配分图（a）及原始地幔标准化微量元素蜘蛛网图（b）
标准化值据Sun and McDonough（1989）
Fig. 5. Chondrite-normalized REE patterns (a) and primi- tive mantle-normalized trace element diagrams (b) of the Baimashan granitic complex
图 6 白马山复式岩体锆石εHf(t)-年龄图解（a）和Hf同位素二阶段模式年龄分布柱状图
Fig. 6. Diagrams of εHf(t) vs. U-Pb ages (a) and frequency histogram of two-stage Hf model ages for the Baimashan granitic complex
图 7 白马山复式岩体的CaO/Na2O-Al2O3/TiO2(a)和Rb/Ba-Rb/Sr(b)图解
底图据Sylvester（1998）
Fig. 7. (a) CaO/Na2O vs. Al2O3/TiO2 and (b) Rb/Ba vs. Rb/Sr diagrams for the Baimashan granitic complex
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Bai, D. Y., Li, B., Zhou, C., et al., 2021. Gold Mineralization Events of the Jiangnan Orogen in Hunan and Their Tectonic Settings. Acta Petrologica en Mineralogica, 40: 897-922(in Chinese with English abstract). Chappel, B. W., White, A. J. R., 1974. Two Contrasting Granite Types. Pacific Geology, 8: 173-174. Chen, W. F., Chen, P. R., Huang, H. Y., et al., 2007. Chronological and Geochemical Studies of Granite and Enclave in Baimashan Pluton, Hunan, South China. Science in China Series D: Earth Sciences, 50: 1606-1627. https://doi.org/10.1007/s11430-007-0073-1 Chu, Y., Lin, W., Faure, M., et al., 2012. Phanerozoic Tectonothermal Events of the Xuefengshan Belt, Central South China: Implications from U-Pb Age and Lu-Hf Determinations of Granites. Lithos, 150: 243-255. https://doi.org/10.1016/j.lithos.2012.04.005 Fu, X., Zhang, D. Y., Jiang, H., et al., 2020. Genesis of the Xianxia Batholith in the Jiangnan Orogenic Belt and Its Geological Significance. Geotectonica et Metallogenia, 176: 543-560(in Chinese with English abstract). Hu, Z., Li, X. H., Luo, T., et al., 2021. Tanz Zircon Megacrysts: a New Zircon Reference Material for the Microbeam Determination of U-Pb Ages and Zr-O Isotopes. Journal of Analytical Atomic Spectrometry, 36: 2715-2734. https://doi.org/10.1039/D1JA00311A Huang, D. L., Wang, X. L., 2019. Reviews of Geochronology, Geochemistry, and Geodynamic Processes of Ordovician-Devonian Granitic Rocks in Southeast China. Journal of Asian Earth Sciences, 184: 104001. doi: 10.1016/j.jseaes.2019.104001 Jiang, S. Y., Zhao, K. D., Jiang, H., et al., 2020. Spatiotemporal Distribution, Geological Characteristics and Metallogenic Mechanism of Tungsten and Tin Deposits in China. Chin. Sci. Bull. , 65: 3730-3745. La Bas, M. J. L., Maitre, R. W. L., Streckeisen, A., et al., 1986. A Chemical Classification of Volcanic Rocks Based on the Total Alkali-Silica Diagram. Journal of Petrology, 27: 745-750. https://doi.org/10.1093/petrology/27.3.745 Li, B., Zhao, K. D., Zhang, Q., et al., 2015. Petrogenesis and Geochemical Characteristics of the Zijinshan Granitic Complex from Fujian Province, South China. Acta Petrologica Sinica, 31(3): 811-828(in Chinese with English abstract). Li, H. Q., Wang, D. H., Chen, F. W., et al., 2008. Study on Chronology of the Chanziping and Daping Gold Deposit in Xuefeng Mountains, Hunan Province. Acta Geologica Sinica, 82: 900-905(in Chinese with English abstract). Li, J. H., Zhang, Y. Q., Xu, X. B., et al., 2014. SHRIMP U-Pb Dating of Zircon From the Baimashan Longtan Super-unit and Wawutang Granites in Hunan Province and Its Geological Implication. Journal of Jilin University(Earth Science Edition), 44: 157-175(in Chinese with English abstract). Li, W., 2019. Nature and Genesis of the Gutaishan and Yuhengtang Au-Sb Deposits, Xiangzhong District, China (Dissertation). China University of Geosciences, Wuhan(in Chinese with English abstract). Li, W., Xie, G. Q., Mao J. W., et al., 2018. Muscovite 40Ar/39Ar and In Situ Sulfur Isotope Analyses of the Slate-Hosted Gutaishan Au-Sb Deposit, South China: Implications for Possible Late Triassic Magmatic-Hydrothermal Mineralization. Ore Geology Reviews, 101: 839-853. https://doi.org/10.1016/j.oregeorev.2018.08.006 Li, X. H., Long, W. G., Li, Q. L., et al., 2020. Penglai Zircon Megacrysts: a Potential New Working Reference Material for Microbeam Determination of Hf-O Isotopes and U-Pb Age. Geostandards and Geoanalytical Research, 34: 117-134. Li, Z. X., Li, X. H., Wartho, J. A., et al., 2010. Magmatic and Metamorphic Events During the Early Paleozoic Wuyi-Yunkai Orogeny, Southeastern South China: New Age Constraints and Pressure-Temperature Conditions. GSA Bulletin, 122: 772-793. https://doi.org/10.1130/B30021.1 Liu, J. Q., Xie, Y., Zhao, Z., et al., 2017. The Geochronologic Characteristics of Baimashan Granite in Western Hunan Province and Its Geotectonic Significance. Earth Science Frontiers, 20: 25-35(in Chinese with English abstract). Lou, Y. L., Liu, X. H., Zeng, H., et al., 2024. Hydrothermal Apatite U-Pb Dating and In-Situ S Isotope Constraints on the Genesis of the Xingfengshan Au-W Deposit in the Central Hunan Province. Earth Science, 49: 1-13(in Chinese with English abstract). Luo, Z. G., Wang, Y. J., Zhang, F. F., et al., 2010. LA-ICPMS Zircon U-Pb Dating of Jintan and Baimashan Indosinian Granitoids and Its Implications for Diagenesis. Geotectonica et Metallogenia, 134: 282-290(in Chinese). Lv, Y. J., Peng, J. T., Cai, Y. T., 2021. Geochemical Characteristics, U-Pb Dating of HydrothermalTitanite from the Xingfengshan Tungsten Deposit in Hunan Province and Their Geological Significance. Acta Petrologica Sinica, 37: 830-846(in Chinese with English abstract). https://doi.org/10.18654/1000-0569/2021.03.12 Mao, J. W., Xie, G. Q., Guo, C. L., et al., 2008. Spatial-Temporal Distribution of Mesozoic Ore Deposits in South China and Their Metallogenic Settings. Geological Journal of China Universities, 14: 510-526(in Chinese with English abstract). Miller, C. F., McDowell, S. M., Mapes, R. W., 2023. Hot and Cold Granites? Implications of Zircon Saturation Temperatures and Preservation of Inheritance. Geology, 31: 529-532. https://doi.org/10.1130/0091-7613(2003)031<0529:hacgio>2.0.co;2 doi: 10.1130/0091-7613(2003)031<0529:hacgio>2.0.co;2 Pearce, J. A., Harris, N. B., Tindle, A. G., 1984. Trace Element Discrimination Diagrams for the Tectonic Interpretation of Granitic Rocks. Journal of Petrology, 25: 956-983. https://doi.org/10.1093/petrology/25.4.956 Peng, J. T., Wang, C., Li, Y. K., et al., 2021. Geochemical Characteristics and Sm-Nd Geochronology of Scheelite in the Baojinshan Ore District, Central Hunan. Acta Petrologica Sinica, 37(3): 665-682(in Chinese with English abstract). https://doi.org/10.18654/1000-0569/2021.03.02 Shu, L. S., Wang, B., Cawood, P. A., et al., 2015. Early Paleozoic and Early Mesozoic Intraplate Tectonic and Magmatic Events in the Cathaysia Block, South China. Tectonics, 34: 1600-1621. https://doi.org/10.1002/2015TC003835 Song, M. J., Shu, L. S., Santosh, M., et al., 2015. Late Early Paleozoic and Early Mesozoic Intracontinental Orogeny in the South China Craton: Geochronological and Geochemical Evidence. Lithos, 232: 360-374. https://doi.org/10.1016/j.lithos.2015.06.019 Sun, S. S. and McDonough, W. F., 1989. Chemical and Isotopic Systematics of Oceanic Basalts: Implications for Mantle Composition and Processes. Geological Society, London, Special Publications, 42: 313-345. Sylvester, P. J., 1998. Post-Collisional Strongly Peraluminous Granites. Lithos, 45: 29-44. Tang, Y., Wang, Q., Yang, Y. L., et al., 2022. Petrogenesis and Geodynamic Implications of the Baimashan Granitic Complex in Central Hunan, South China. Geological Journal, 1-28. https://doi.org/10.1002/gj.4568 Wang, C., Peng, J. T., Xu, J. B., et al., 2021. Petrogenesis and Metallogenic Effect of the Baimashan Granitic Complex in Central Hunan, South China. Acta Petrologica Sinica, 37: 805-829(in Chinese with English abstract). Whalen, J. B., Currie, K. L., Chappell, B. W., 1987. A-Type Granites: Geochemical Characteristics, Discrimination and Petrogenesis. Contributions to Mineralogy and Petrology, 95: 407-419. https://doi.org/10.1007/BF00402202 Wiedenbeck, M., Alle, P., Corfu, F., et al., 1995. Three Natural Zircon Standards for U-Th-Pb, Lu-Hf, Trace Element and REE Analyses. Geostandards Newsletter, 19: 1-23. Wu, F. Y., Li, X. H., Yang, J. W., et al., 2007. Discussions on the Petrogenesis of Granites. Acta Petrologca Sinica, 23(6): 1217-1238(in Chinese with English abstract). Xie, G. Q., Mao, J. W., Li, W., et al., 2019. Granite-Related Yangjiashan Tungsten Deposit, Southern China. Mineralium Deposita, 54: 67-80. https://doi.org/10.1007/s00126-018-0805-5 Xie, G. Q., Mao, J. W., Bagas, L., et al., 2019. Mineralogy and Titanite Geochronology of the Caojiaba W Deposit, Xiangzhong Metallogenic Province, Southern China: Implications for a Distal Eeduced Skarn W Formation. Mineralium Deposita, 54: 459-472. https://doi.org/10.1007/s00126-018-0816-2 Xin, Y. J., Li, J. H., Ratschbacher, L., et al., 2020. Early Devonian (415-400 Ma) A-Type Granitoids and Diabases in the Wuyishan, Eastern Cathaysia: A Signal of Crustal Extension Coeval with the Separation of South China from Gondwana. GSA Bulletin, 132: 2295-2317. https://doi.org/10.1130/B35412.1 Yao, J. L., Cawood, P. A., Shu, L. S., et al., 2019. Jiangnan Orogen, South China: A ~970–820 Ma Rodinia Margin Accretionary Belt. Earth-Science Reviews, 196: 102872. https://doi.org/10.1016/j.earscirev.2019.05.016 Zhang, Y. P., Zhang, J., Chen, B. H., et al., 2015. Geochronology of Baimashan Granitic Composite Batholith of Hunan Province and Its Constraints on the Timing of Regional Deformation. Acta Geologica Sinica, 89: 1-17(in Chinese with English abstract). Zhang, Z. Y., Xie, G. Q., Mao, J. W., et al., 2017. Sm-Nd Dating and In-Situ LA-ICP-MS Trace Element Analyses of Scheelite from the Longshan Sb-Au deposit, Xiangzhong Metallogenic Province, South China. Minerals, 9: 87. https://doi.org/10.3390/min9020087 Zhou, X. M., Sun, T., Shen, W. Z., et al., 2006. Petrogenesis of Mesozoic Granitoids and Volcanic Rocks in South China: a Response to Tectonic Evolution. Episodes, 29: 26-33. 柏道远, 李彬, 周超, 等, 2021. 江南造山带湖南段金矿成矿事件及其构造背景. 岩石矿物学杂志, 40: 897-922. 陈卫锋, 陈培荣, 黄宏业, 等, 2007. 湖南白马山岩体花岗岩及其包体的年代学和地球化学研究. 中国科学(D辑: 地球科学), 37: 873-893. 付翔, 张达玉, 蒋华, 等, 2020. 江南造山带仙霞复式岩体的成因研究. 大地构造与成矿学, 176: 543-560. 蒋少涌, 赵葵东, 姜海, 等, 2020. 中国钨锡矿床时空分布规律、地质特征与成矿机制研究进展. 科学通报, 65: 3730-3745. 李斌, 赵葵东, 张倩, 等, 2015. 福建紫金山复式岩体的地球化学特征和成因. 岩石学报, 31: 811-828. 李建华, 张岳桥, 徐先兵, 等, 2014. 湖南白马山龙潭超单元、瓦屋塘花岗岩锆石SHRIMP U-Pb年龄及其地质意义. 吉林大学学报(地球科学版), 44: 158-175. 李华芹, 王登红, 陈富文, 等, 2008. 湖南雪峰山地区铲子坪和大坪金矿成矿作用年代学研究. 地质学报, 82: 900-905. 李伟, 2019. 湘中地区古台山和玉横塘Au-Sb矿床成矿机制研究(博士学位论文). 武汉: 中国地质大学. 刘建清, 谢渊, 赵瞻, 等, 2017. 湖南雪峰山地区白马山花岗岩年代学特征及构造意义. 地学前缘, 20: 25-35. 娄元林, 刘贤红, 曾昊, 等, 2024. 湘中杏枫山金钨矿床成因: 热液磷灰石U-Pb定年和原位S同位素制约. 地球科学, 49: 1-13. doi: 10.3799/dqkx.2024.059 罗志高, 王岳军, 张菲菲, 等, 2010. 金滩和白马山印支期花岗岩体LA-ICPMS锆石U-Pb定年及其成岩启示. 大地构造与成矿学, 34: 282-290. 吕沅峻, 彭建堂, 蔡亚飞, 2021. 湖南杏枫山钨矿床热液榍石的地球化学特征、U-Pb定年及其地质意义. 岩石学报, 37: 830-846. 毛景文, 谢桂青, 郭春丽, 等, 2008. 华南地区中生代主要金属矿床时空分布规律和成矿环境. 高校地质学报, 14: 510-526. 彭建堂, 王川, 李玉坤, 等, 2021. 湖南包金山矿区白钨矿的地球化学特征及Sm-Nd同位素年代学. 岩石学报, 37: 665-682. 王川, 彭建堂, 徐接标, 等, 2021. 湘中白马山复式岩体成因及其成矿效应. 岩石学报, 37: 805-829. 吴福元, 李献华, 杨进辉, 等, 2007. 花岗岩成因研究的若干问题. 岩石学报, 23: 1217-1238. 张义平, 张进, 陈必河, 等, 2015. 湖南白马山复式花岗岩基年代学及对区域构造变形时间的约束. 地质学报, 89: 1-17. -
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