Origin and Geological Significance of Diabase Dikes from Hongge Layered Intrusion in Panxi Region
-
摘要: 为了了解峨眉山地幔柱岩浆系统的演化过程，对红格超大型钒钛磁铁矿矿床中辉绿岩脉进行了全岩主微量、矿物原位成分和同位素研究，并利用MELTS软件进行了岩浆过程模拟计算.研究发现，红格辉绿岩脉具有与峨眉山高钛玄武岩一致的稀土元素配分型式和Sr同位素组成，表明其起源于峨眉山地幔柱.辉绿岩含有斑晶和基质两个世代矿物，从斑晶核部到边部和基质，单斜辉石Mg#值较为连续变化，而斜长石An值具有明显的间断.MELTS模拟表明，这种成分变化难以用简单的岩浆上升侵位解释，反映了辉绿岩脉在岩浆演化过程中可能还与同期的正长质岩浆发生了混合.我们的研究表明，峨眉山地幔柱岩浆作用具有穿地壳、多期次、多阶段演化的特点，并且同源岩浆混合也是一个不可忽视的方面.Abstract: In order to understand the evolution of the magmatic system of the Emeishan mantle plume, whole-rock major and trace elements, in-situ mineral composition and isotope studies as well as MELTS simulation were carried out on the diabase dikes in the Hongge giant Fe-Ti-V oxide deposit. The study shows that the Hongge diabases have consistent REE patterns and Sr-isotope compositions with the Emeishan high-Ti basalts, indicating that the diabases were derived from the Emeishan mantle plume. The Hongge diabases contain two generations of minerals, i.e., phenocryst and matrix. It is found that Mg# value of clinopyroxene varied continuously from the phenocryst core to rim and matrix, while the An values of plagioclase show an obvious discontinuity. The MELTS simulation results show that the composition variation could not be explained by a simple process of magma ascending, reflecting the basaltic magma may have mixed with the synchronous syenitic magma during the evolution process. Our research suggests that the Emeishan mantle plume magmatism is characterized by trans-crustal, poly-phase and multi-stage evolution, and "self-mixing" between co-genetic magmas is also nonnegligible.
-
Key words:
- diabase /
- layered intrusion /
- Panxi region /
- Emeishan large igneous province /
- petrology
-
图 1 攀西地区峨眉山大火成岩省岩浆岩分布简图
Fig. 1. Distribution of igneous rocks of the Emeishan large igneous province in the Panxi region
图 2 红格镁铁‒超镁铁质层状岩体中辉绿岩脉野外照片
a.层状岩体被正长岩脉穿插，正长岩脉又被辉绿岩脉穿插；b.辉绿岩与正长岩呈相互混合的特征；c.辉绿岩被网脉状正长岩穿插为碎块状；d.辉绿岩被正长岩脉穿插破碎
Fig. 2. Field photographs of diabase dikes in the Hongge mafic-ultramafic layered intrusion
图 3 红格辉绿岩脉岩相显微照片
a.斑晶单斜辉石颗粒边部相对核部含有较多的铁钛氧化物微出溶体；b.斑晶斜长石颗粒边部含有微粒单斜辉石包裹体；c.多个斑晶斜长石颗粒集中出现，局部可见单斜辉石小颗粒呈串珠状地从边部穿插入斑晶斜长石之中；d.斜长石、单斜辉石、铁钛氧化物等微粒基质矿物相粒度相近，较为均匀分布，可见细柱状磷灰石颗粒
Fig. 3. Microphotographs of textures of the Hongge diabase dike
图 4 红格辉绿岩及相关岩石主量元素成分二元图解
数据来源：峨眉山火山岩（Qi et al.，2008）；攀枝花边缘相细粒辉长岩和含橄榄石斑晶辉长岩（Bai et al.，2019）；红格（炉库和白草矿区）正长岩脉和正长岩体（王汾连，2014）；红格（炉库矿区）辉绿岩脉（本研究）
Fig. 4. Binary diagrams of major elements of the Hongge diabase and related rocks
图 5 红格辉绿岩及相关岩石球粒陨石标准化稀土元素配分图（a、c）和原始地幔标准化微量元素蛛网图（b、d）
球粒陨石和原始地幔标准化值来自Sun and McDonough（1989）.其他数据来源：峨眉山高钛玄武岩（Qi et al.，2008）；攀枝花边缘相细粒辉长岩和含橄榄石斑晶辉长岩（Bai et al.，2019）；红格（炉库和白草矿区）正长岩脉和正长岩体（王汾连，2014）；红格（炉库矿区）辉绿岩脉（本研究）
Fig. 5. Chondrite-normalized REE patterns (a, c) and primitive mantle-normalized trace element spidergrams (b, d) of the Hongge diabase and related rocks
图 6 单斜辉石斑晶背散射电子图像（a）及元素面分布图（b、c、d）
Pl.斜长石；Cpx.单斜辉石；Mt.磁铁矿；Ilm.钛铁矿
Fig. 6. BSE image (a) and X-ray elemental intensity maps (b, c, d) of clinopyroxene phenocryst
图 7 红格辉绿岩脉单斜辉石和斜方辉石成分变化图解
Fig. 7. Composition variation of clinopyroxene and orthopyroxene within the Hongge diabase
图 8 斜长石斑晶背散射电子图像（a）及元素面分布图（b、c、d）
Pl.斜长石；Cpx.单斜辉石；Mt.磁铁矿；Ilm.钛铁矿
Fig. 8. BSE image (a) and X-ray elemental intensity maps (b, c, d) of plagioclase phenocryst
图 9 红格辉绿岩脉斜长石成分变化图解
Fig. 9. Composition variation diagram of plagioclase within the Hongge diabase
图 10 红格辉绿岩脉角闪石成分变化及分类图解
Fig. 10. Composition variation and classification of amphibole within the Hongge diabase
图 11 红格辉绿岩脉斜长石Sr同位素与该地区其他岩石比较
Sr同位素数据来源：峨眉山高钛玄武岩（Xu et al.，2001）、红格层状岩体（Zhong et al.，2003）、红格（炉库和白草矿区）正长岩体和正长岩脉（王汾连等，2015）、红格辉绿岩脉斜长石（本研究）
Fig. 11. Comparison of plagioclase Sr isotopic compositions of the Hongge diabase with other rocks in this area
图 12 MELTS模拟单斜辉石Mg#值（a）和斜长石An值（b）随岩浆演化而变异图解
MELTS模拟分为深部和浅部两个阶段.深部浆房的分离结晶：压力2 kbar，氧逸度QFM，初始成分见附表 8中原生岩浆a. 待岩浆演化至与An=54.8的斜长石平衡时，快速向上侵位，在浅部（1 kbar）就位.浅部岩浆房的分离结晶：初始成分见附表 8中演化岩浆b和d，压力1 kbar，氧逸度QFM
Fig. 12. MELTS modelled clinopyroxene Mg# value (a) and plagioclase An value (b) variation diagram with magma evolution
-
[1] Bai, Z. J., Zhong, H., Hu, R. Z., et al., 2019. Composition of the Chilled Marginal Rocks of the Panzhihua Layered Intrusion, Emeishan Large Igneous Province, SW China: Implications for Parental Magma Compositions, Sulfide Saturation History and Fe⁃Ti Oxide Mineralization. Journal of Petrology, 60(3): 619-648. https://doi.org/10.1093/petrology/egz008 [2] Chen, M. T., Wei, J. H., Shi, W. J., et al., 2020. Origin of Middle Silurian Diabase Dike in the Taining District, South China: Implications for Intracontinental Orogeny. Earth Science, 45(3): 892-909 (in Chinese with English abstract). [3] Daly, R. A., 1914. Igneous Rocks and Their Origin. Nature, 93: 449-450. https://doi.org/10.1038/093449a0 [4] Deng, G., Kang, J., Nan, X., et al., 2021. Barium Isotope Evidence for Crystal⁃Melt Separation in Granitic Magma Reservoirs. Geochimica et Cosmochimica Acta, 292: 115-129. https://doi.org/10.1016/j.gca.2020.09.027 [5] Erdmann, S., Martel, C., Pichavant, M., et al., 2014. Amphibole as an Archivist of Magmatic Crystallization Conditions: Problems, Potential, and Implications for Inferring Magma Storage Prior to the Paroxysmal 2010 Eruption of Mount Merapi, Indonesia. Contributions to Mineralogy and Petrology, 167(6): 1-23. https://doi.org/10.1007/s00410⁃014⁃1016⁃4 [6] He, B., Xu, Y. G., Xiao, L., et al., 2006. Sedimentary Responses to Uplift of Emeishan Mantle Plume and Its Implications. Geological Review, 52(1): 30-37 (in Chinese with English abstract). [7] Kamenetsky, V. S., Chung, S. L., Kamenetsky, M. B., et al., 2012. Picrites from the Emeishan Large Igneous Province, SW China: A Compositional Continuum in Primitive Magmas and Their Respective Mantle Sources. Journal of Petrology, 53(10): 2095-2113. https://doi.org/10.1093/petrology/egs045 [8] Kimura, J., Takahashi, T., Chang, Q., 2013. A New Analytical Bias Correction for In Situ Sr Isotope Analysis of Plagioclase Crystals Using Laser⁃Ablation Multiple⁃ Collector Inductively Coupled Plasma Mass Spectrometry. Journal of Analytical Atomic Spectrometry, 28(6): 945-957. https://doi.org/10.1039/C3JA30329B [9] Leake, B. E., Woolley, A. R., Arps, C. E. S., et al., 1997. Nomenclature of Amphiboles: Report of the Subcommittee on Amphiboles of the International Mineralogical Association Commission on New Minerals and Mineral Names. Mineralogical Magazine, 61(405): 295-310. doi: 10.1180/minmag.1997.061.405.13 [10] Li, H. B., Zhang, Z. C., Lü, L. S., et al., 2012. Petrological, Geochemical and Geometric Characteristics of Dyke Swarms and Their Tectonic Significance. Acta Petrologica et Mineralogica, 31(1): 91-103 (in Chinese with English abstract). [11] Li, T., Liu, L., Liao, X. Y., et al., 2020. Geochemistry, Sr⁃Nd⁃Pb Isotopic Compositions and Zircon U⁃Pb Geochronology of Neoproterozoic Mafic Dyke in the Douling Complex, South Qinling Belt, China. Journal of Earth Science, 31(2): 237-248. https://doi.org/10.1007/s12583⁃020⁃1298⁃6 [12] Liao, M., Tao, Y., Song, X., et al., 2015. Multiple Magma Evolution and Ore⁃Forming Processes of the Hongge Layered Intrusion, SW China: Insights from Sr⁃Nd Isotopes, Trace Elements and Platinum⁃Group Elements. Journal of Asian Earth Sciences, 113: 1082-1099. https://doi.org/10.1016/j.jseaes.2015.03.028 [13] Liao, M. Y., Tao, Y., Song, X. Y., et al., 2016. Study of Oxygen Fugacity during Magma Evolution and Ore Genesis in the Hongge Mafic⁃Ultramafic Intrusion, the Panxi Region, SW China. Acta Geochimica, 35(1): 25-42. https://doi.org/10.1007/s11631⁃015⁃0064⁃4 [14] Liu, J. H., Liu, F. T., He, J. K., et al., 2000. Seismic Imaging Study of the Panxi Ancient Rift⁃Crust⁃Mantle Structure and Its Evolution. Science in China (Series D: Earth Sciences), 30(B12): 9-15 (in Chinese). [15] Liu, P. P., Zhou, M. F., Chen, W. T., et al., 2014. Using Multiphase Solid Inclusions to Constrain the Origin of the Baima Fe⁃Ti⁃(V) Oxide Deposit, SW China. Journal of Petrology, 55(5): 951-976. https://doi.org/10.1093/petrology/egu012 [16] Luo, Z. H., Yang, Z. F., Dai, G., et al., 2013. Crystal Populations of Igneous Rocks and Their Implications in Genetic Mineralogy. Geology in China, 40(1): 176-181 (in Chinese with English abstract). [17] Morimoto, N., 1988. Nomenclature of Pyroxenes. Mineralogy and Petrology, 39(1): 55-76. https://doi.org/10.1007/BF01226262 [18] Putirka, K. D., 2008. Thermometers and Barometers for Volcanic Systems. Reviews in Mineralogy and Geochemistry, 69(1): 61-120. https://doi.org/10.2138/rmg.2008.69.3 [19] Qi, L., Wang, C. Y., Zhou, M. F., 2008. Controls on the PGE Distribution of Permian Emeishan Alkaline and Peralkaline Volcanic Rocks in Longzhoushan, Sichuan Province, SW China. Lithos, 106(3-4): 222-236. https://doi.org/10.1016/j.lithos.2008.07.012 [20] Ridolfi, F., Renzulli, A., Puerini, M., 2010. Stability and Chemical Equilibrium of Amphibole in Calc⁃Alkaline Magmas: An Overview, New Thermobarometric Formulations and Application to Subduction⁃Related Volcanoes. Contributions to Mineralogy and Petrology, 160(1): 45-66. https://doi.org/10.1007/s00410⁃009⁃0465⁃7 [21] Shellnutt, J. G., Zhou, M. F., 2007. Permian Peralkaline, Peraluminous and Metaluminous A⁃Type Granites in the Panxi District, SW China: Their Relationship to the Emeishan Mantle Plume. Chemical Geology, 243(3-4): 286-316. https://doi.org/10.1016/j.chemgeo.2007.05.022 [22] Sun, S. S., McDonough, W. F., 1989. Chemical and Isotopic Systematics of Oceanic Basalts: Implications for Mantle Composition and Processes. Geological Society, London, Special Publications, 42(1): 313-345. https://doi.org/10.1144/GSL.SP.1989.042.01.19 [23] Tan, Q. Y., Chen, B., Zhang, Y. S., et al., 2011. Characteristics and Current Situation of Comprehensive Utilization of Vanadium Titano⁃Magnetite Resources in Panxi Region. Multipurpose Utilization of Mineral Resources, 6(6): 6-10 (in Chinese with English abstract). [24] Wager, L. R., 1960. The Major Element Variation of the Layered Series of the Skaergaard Intrusion and a Re⁃ Estimation of the Average Composition of the Hidden Layered Series and of the Successive Residual Magmas. Journal of Petrology, 1(1): 364-398. https://doi.org/10.1093/petrology/1.1.364 [25] Wang, B. Z., Chen, J., Zhang, J. M., et al., 2020. Discovery and Significance of Cretaceous Lamprophyre Dike Group in Quanji Block of Northern Tibetan Plateau. Earth Science, 45(4): 1136-1150 (in Chinese with English abstract). [26] Wang, C. Y., Zhou, M., Yang, S., et al., 2014. Geochemistry of the Abulangdang Intrusion: Cumulates of High⁃Ti Picritic Magmas in the Emeishan Large Igneous Province, SW China. Chemical Geology, 378: 24-39. https://doi.org/10.1016/j.chemgeo.2014.04.010 [27] Wang, F. L., 2014. Origin of the ~260 Ma Nb⁃Ta⁃Mineralization in the Panxi Region, SW China: A Case Study on the Luku and Baicao Mines (Dissertation). Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou (in Chinese with English abstract). [28] Wang, F. L., Zhao, T. P., Wang, Y., 2015. Petrogenisis of Permian Nb⁃Ta Mineralized Syenitic Dikes in the Panxi District, SW China. Acta Petrologica Sinica, 31(6): 1797-1805 (in Chinese with English abstract). [29] Wang, K., Dong, H., Cao, Y. H., et al., 2017. Research Status and Existing Problems of Silicate Liquid Immiscibility in Intermediate⁃Basic Magma. Geological Review, 63(3): 739-757 (in Chinese with English abstract). [30] Wang, Y., Qian, Q., Liu, L., et al., 2000. Major Geochemical Characteristics of Bimodal Volcanic Rocks in Different Geochemical Environments. Acta Petrologica Sinica, 16(2): 169-173 (in Chinese with English abstract). [31] Wang, Y., Xing, C. M., 2018. Compositions of Clinopyroxenes from the Ertan High⁃Ti Basalt and Baima Layered Intrusion of the Emeishan Large Igneous Province: Implication for a Genetic Link of the High⁃Ti Basalt and Layered Intrusion. Bulletin of Mineralogy, Petrology and Geochemistry, 37(6): 1019-1034 (in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-KYDH202101013.htm [32] Wu, B., Cao, J. X., Tang, Y. Q., et al., 2012. Geological Features of the Vanadium⁃Titanium Magnetite Deposit in the Hongge Area and Its Geophysical Prospecting. Geology and Exploration, 48(1): 140-147 (in Chinese with English abstract). [33] Xu, Y., Chung, S., Jahn, B., et al., 2001. Petrologic and Geochemical Constraints on the Petrogenesis of Permian⁃Triassic Emeishan Flood Basalts in Southwestern China. Lithos, 58(3-4): 145-168. https://doi.org/10.1016/S0024⁃4937(01)00055⁃X [34] Zhang, L., Ren, Z. Y., Wu, Y. D., et al., 2018. Strontium Isotope Measurement of Basaltic Glasses by Laser Ablation Multiple Collector Inductively Coupled Plasma Mass Spectrometry Based on a Linear Relationship between Analytical Bias and Rb/Sr Ratios. Rapid Communications in Mass Spectrometry, 32(2): 105-112. https://doi.org/10.1002/rcm.8011 [35] Zhang, L., Ren, Z., Xia, X., et al., 2015. Isotope Maker: A Matlab Program for Isotopic Data Reduction. International Journal of Mass Spectrometry, 392: 118-124. https://doi.org/10.1016/j.ijms.2015.09.019 [36] Zhang, Y. X., Luo, Y. N., Yang, C. X., 1988. Panxi Rift Valley. Geological Publishing House, Beijing (in Chinese). [37] Zhong, H., Campbell, I. H., Zhu, W. G., et al., 2011. Timing and Source Constraints on the Relationship between Mafic and Felsic Intrusions in the Emeishan Large Igneous Province. Geochimica et Cosmochimica Acta, 75(5): 1374-1395. https://doi.org/10.1016/j.gca.2010.12.016 [38] Zhong, H., Hu, R. Z., Wilson, A. H., et al., 2005. Review of the Link between the Hongge Layered Intrusion and Emeishan Flood Basalts, Southwest China. International Geology Review, 47(9): 971-985. https://doi.org/10.2747/0020⁃6814.47.9.971 [39] Zhong, H., Yao, Y., Hu, S. F., et al., 2003. Trace⁃ Element and Sr⁃Nd Isotopic Geochemistry of the PGE⁃Bearing Hongge Layered Intrusion, Southwestern China. International Geology Review, 45(4): 371-382. https://doi.org/10.2747/0020⁃6814.45.4.371 [40] Zhong, H., Zhu, W. G., 2006. Geochronology of Layered Mafic Intrusions from the Pan⁃Xi Area in the Emeishan Large Igneous Province, SW China. Mineralium Deposita, 41(6): 599-606. https://doi.org/10.1007/s00126⁃006⁃0081⁃7 [41] Zhou, Y. Q., Zhou, T. F., Ma, C. Q., et al., 2018. Transcrustal Magmatic System of Early Cretaceous (Qingshan Stage) in Eastern Shandong and the Basin Formation Related to "Thermal Upwelling⁃Detachment". Earth Science, 43(10): 3373-3390 (in Chinese with English abstract). [42] 陈梦婷, 魏俊浩, 石文杰, 等, 2020. 泰宁地区中志留世辉绿岩脉成因及对陆内造山作用的制约. 地球科学, 45(3): 892-909. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX202003016.htm [43] 何斌, 徐义刚, 肖龙, 等, 2006. 峨眉山地幔柱上升的沉积响应及其地质意义. 地质论评, 52(1): 30-37. https://www.cnki.com.cn/Article/CJFDTOTAL-DZLP200601006.htm [44] 李宏博, 张招崇, 吕林素, 等, 2012. 岩墙群的岩石学、地球化学和几何学特征及其大地构造意义. 岩石矿物学杂志, 31(1): 91-103. https://www.cnki.com.cn/Article/CJFDTOTAL-YSKW201201014.htm [45] 刘建华, 刘福田, 何建坤, 等, 2000. 攀西古裂谷的地震成像研究——壳幔构造特征及其演化推断. 中国科学(D辑: 地球科学), 30(B12): 9-15. https://www.cnki.com.cn/Article/CJFDTOTAL-JDXK2000S1001.htm [46] 罗照华, 杨宗锋, 代耕, 等, 2013. 火成岩的晶体群与成因矿物学展望. 中国地质, 40(1): 176-181. https://www.cnki.com.cn/Article/CJFDTOTAL-DIZI201301014.htm [47] 谭其尤, 陈波, 张裕书, 等, 2011. 攀西地区钒钛磁铁矿资源特点与综合回收利用现状. 矿产综合利用, 6(6): 6-10. https://www.cnki.com.cn/Article/CJFDTOTAL-KCZL201106003.htm [48] 王秉璋, 陈静, 张金明, 等, 2020. 青藏高原北部全吉地块白垩纪煌斑岩脉群的发现及意义. 地球科学, 45(4): 1136-1150. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX202004004.htm [49] 王汾连, 2014. 攀西地区二叠纪铌钽矿的成因研究: 以炉库和白草矿区为例(博士学位论文). 广州: 中国科学院广州地球化学研究所. [50] 王汾连, 赵太平, 王焰, 2015. 攀西地区二叠纪赋存铌钽矿的正长岩脉的成因探讨. 岩石学报, 31(6): 1797-1805. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB201506022.htm [51] 王坤, 董欢, 曹永华, 等, 2017. 中基性岩浆的不混溶作用及存在的问题. 地质论评, 63(3): 739-757. https://www.cnki.com.cn/Article/CJFDTOTAL-DZLP201703014.htm [52] 王焰, 钱青, 刘良, 等, 2000. 不同构造环境中双峰式火山岩的主要特征. 岩石学报, 16(2): 169-173. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200002003.htm [53] 王焰, 邢长明, 2018. 峨眉山大火成岩省二滩高钛玄武岩和白马层状岩体中单斜辉石的成分特征及其成因指示. 矿物岩石地球化学通报, 37(6): 1019-1034. https://www.cnki.com.cn/Article/CJFDTOTAL-KYDH201806004.htm [54] 武斌, 曹俊兴, 唐玉强, 等, 2012. 红格地区钒钛磁铁矿地质特征及地球物理找矿的探讨. 地质与勘探, 48(1): 140-147. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKT201201018.htm [55] 张云湘, 骆耀南, 杨崇喜, 1988. 攀西裂谷. 北京: 地质出版社. [56] 周瑶琪, 周腾飞, 马昌前, 等, 2018. 山东东部早白垩世青山期穿地壳岩浆系统与热隆滑脱成盆. 地球科学, 43(10): 3373-3390. https://www.cnki.com.cn/Article/CJFDTOTAL-DQKX201810003.htm -
下载:
点击查看大图
计量
- 文章访问数: 138
- HTML全文浏览量: 72
- PDF下载量: 29
- 被引次数: 0
