Mineral Geochemistry of Rutile in Eclogite and Its Implications
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摘要: 金红石的微量元素分析在俯冲带地质作用示踪、榴辉岩原岩判别以及形成温度估算等的研究中具有重要指示作用, 其U-Pb同位素和Hf同位素分析则对于确定高级变质岩的冷却时代以及探讨物质来源和壳幔作用过程具有重要意义.初步研究显示, 苏鲁超高压变质地体及大陆科学钻探岩心中不同产状、不同类型的榴辉岩中的金红石具有不同的微量元素特征, 对榴辉岩原岩及金红石形成温度具有很好的指示作用; 3个金红石样品的Pb同位素组成在逐步淋溶分析的某个中间阶段和最后阶段均出现有相似规律的2次突变, 其余阶段则相对平稳, 有可能反映了金红石在其生长过程中构造环境背景的变化.进一步对金红石进行详细系统的矿物地球化学分析, 有望在苏鲁地体大陆深俯冲-折返过程的地球动力学及榴辉岩型金红石矿床的研究中获得一些新的认识.Abstract: The study of rutile's mineral geochemistry can provide important information for the investigation of petrology and the geodynamics of a subduction zone. Rutile-bearing eclogite (eclogitic-rutile deposit) in Sulu UHPM terrane and the > 5 000 m deep CCSD main hole provide a good opportunity for the geochemical investigation of rutile. Preliminary research has shown that eclogites of different occurrences and different types in Sulu UHPM terrane and CCSD main hole have different trace element contents, which indicate that trace elements in rutile can serve as a practical tool for provenance tracing of eclogite and for estimation of rutile mineralization temperature. Pb isotope composition of 3 rutile samples showed two abrupt changes during step-leaching analysis, which may be a reflection of tectonic condition variation during the growth history of rutile, and have potential use in tracing the process of continental subduction-exhumation. Further detailed studies on the geochemistry of rutile are needed to provide new knowledge on the geodynamics of the subduction-exhumation of Sulu terrane, and on the eclogitic rutile deposit.
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Key words:
- rutile /
- trace elements /
- isotope /
- UHPM rocks /
- eclogitic rutile ore
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[1] Brenan, J.M., Shaw, H.F., Phinney, D. L., et al., 1994. Rutile-aqueous fluid partitioning of Nb, Ta, H, Zr, U and Th: Implications for high field strength element depletions in island-arc basalts. Earth Planet. Sci. Lett. , 128, 327-339. doi: 10.1016/0012-821X(94)90154-6 [2] Chen, Z.Y., Chen, Y.C., Wang, D.H., et al., 2005. Rutiles in eclogite from Sulu UHPM terrane: A preliminary study. In: Mao, J.W., Bierlein, F.P., eds., Mineral deposit research: Meeting the global challenge(Proceeding of the 8th Biennial SGA meeting). Springer, 731-733. [3] Mathieu, C., O'Reilly, S.Y., Griffin, W.L., et al., 2005. Hf isotopes of MARID(mica-amphibole-rutile-ilmenite-diopside)rutile trace metasomatic processes in the lithospheric mantle. Geology, 33: 45-48. [4] Foley, S.F., Barth, M.G., Jenner, G.A., 2000. Rutile/melt partition coefficients for trace elements and an assessment of the influence of rutile on the trace element characteristics of subduction zone magmas. Geochim. Cosmochim. Acta, 64: 933-938. doi: 10.1016/S0016-7037(99)00355-5 [5] Franz, L., Romer, R.L., Klemd, R., et al., 2001. Eclogite facies quartz veins within metabasites of the Dabie Shan(eastern China): Pressure temperature-time-deformation path, composition of the fluid phase and fluid flow during exhumation of high-pressure rocks. Contrib. Mineral Petrol. , 141: 322-346. doi: 10.1007/s004100000233 [6] Gftze, J., 1996. Genetic information of accessory minerals in clastic sediments. Zentralbl. Geol. Palaontol., Teil 1, 101-118. [7] Green, T.H., 1995. Significance of Nb/Ta as an indicator of geochemical processes in the crust-mantle system. Chem. Geol., 120, 347-359. doi: 10.1016/0009-2541(94)00145-X [8] Green, T. H., 2000. The effect of rutile on high-field-strength element behaviour in the crust-mantle system. EMPG Ⅷ, J. Con f. Abst. , 5: 44. [9] Huang, J.P., Ma, D.S., Liu, C., et al., 2002. Rutile deposite in eclogite of ultrahigh pressure metamorphic belt in the northeast of Jiangsu Province and ore genesis. Journal of Nanjing University(Natural Science), 38(4): 514-524(in Chinese with English abstract). [10] Jenner, G.A., Foley, S.F., Jackson, S.E., et al., 1993. Determination of partition coefficients for trace elements in high pressure-temperature experimental run products by laser ablation microprobe-inductively coupled plasma-mass spectrometry(LAM-ICP-MS). Geochim. Cosmochim. Acta, 57, 5099-5103. doi: 10.1016/0016-7037(93)90611-Y [11] Kalfoun, F., Ionov, D., Merlet, C., 2002. HFSE residence and Nb/Ta ratios in metasomatised, rutile-bearing mantle peridotites. Earth and Planetary Science Letters, 199: 49-65. doi: 10.1016/S0012-821X(02)00555-1 [12] Li, Q.L., Li, S.G., Zhou, H.Y., et al., 2001. U-Pb age of rutile in UHP eclogite: The evidence of rapid cooling. Chinese Science Bulletin, 46(19): 1655-1658(in Chinese). doi: 10.1360/csb2001-46-19-1655 [13] Li, Q.L., Li, S.G., Zheng, Y.F., et al., 1999. A high precision U-Pb age of metamorphic rutile in coesite-bearing eclogite from the Dabie Mountains in central China: A new constraint on the cooling history. Chemical Geology, 200: 255-265. [14] Li, Q.L., Li, S.G., Zheng, Y.F., et al., 2003. A high precision U-Pb age of metamorphic rutile in coesite-bearing eclogite from the Dabie Mountains in central China: A new constraint on the cooling history. Chemical Geology, 200: 255-265. doi: 10.1016/S0009-2541(03)00194-3 [15] Ling, W.L., Cheng, J.P., 2003. New constraints of Lu-Hf isotope on some critical geological issues(Ⅰ): Early evolution of the earth. Geological Science and Technology Information, 18(1): 79-84(in Chinese with English abstract). [16] Preston, J., Hartley, A., Hole, M., et al., 1998. Integrated whole-rock trace element geochemistry and heavy mineral chemistry studies: Aids to the correlation of continental red-bed reservoir in the Beryl Field, UK North Sea. Pet. Geosci., 4: 7-16. doi: 10.1144/petgeo.4.1.7 [17] Preston, J., Hartley, A., Mange-Rajetzky, M., et al., 2002. The provenance of Triassic continental sandstones from the Beryl field, northern North Sea: Mineralogical, geochemical, and sedimentological constraints. J. Sediment. Res., 72, 18-29. doi: 10.1306/042201720018 [18] Rudnick, R. L., Barth, M., Horn, I., et al., 2000. Rutile bearing refractory eclogites missing link between continents and depleted mantle. Science, 287: 278-281. doi: 10.1126/science.287.5451.278 [19] Song, Y.R., Jin, Z.M., 2002. Nanometer-sized UHP Rutile: Tracing the depth of continental deep subduction. Earth Science Frontier, 9(4): 267-272(in Chinese with English abstract). [20] Stalder, R., Foley, S.F., Brey, G.P., et al., 1998. Mineral aqueous fluid partitioning of trace elements at 900-1 200℃ and 3.0 GPa to 5.7 GPa: New experimental data set for garnet, clinopyroxene and rutile and implications for mantle metasomatism. Geochim. Cosmochim. Acta, 62: 1781-1801. [21] Treloar, P.J., O'Brien, P.J., Parrish, R.R., et al., 2003. Exhumation of early Tertiary, coesite-bearing eclogites from the Pakistan Himalaya. Journal of the Geological Society, London, 160: 367-376. doi: 10.1144/0016-764902-075 [22] Wang, D.H., Li, H.Q., Chen, Y.C., et al., 2005. Lead isotopic composition of rutiles from the Chinese Continental Scientific Drilling(CCSD) hole and its genetic significance for the superlarge rutile deposit in Maobei, Jiangsu Province. In: Mao, J.W., Bierlein, F.P., eds., Mineral deposit research: Meeting the global challenge(Proceeding of the 8th Biennial SGA meeting). Springer, 69-72. [23] Wang, R.C., Wang, S., Qiu, J.S., et al., 2005. Rutile in the UHP eclogites from the CCSD main drillhole(Donghai, eastern China): Trace element geochemistry and metallogenetic implications. Acta Petrologica Sinica, 21(2): 465-474(in Chinese with English abstract). [24] Xu, J., Chen, Y. C., Wang, D. H., et al., 2004. Titanium mineralization in the ultrahigh-pressure metamorphic rocks from Chinese Continental Scientific Drilling 100-2 000 m main hole. Acta Petrologica Sinica, 20(1): 19-26(in Chinese with English abstract). [25] Xu, Z.Q., 2004. The scientific goals and investigation progresses of the Chinese Continental Scientific Drilling Project. Acta Petrologica Sinica, 20(1): 1-8(in Chinese with English abstract). [26] Yang, J.S., Bai, W.J., Fang, Q.S., et al., 2003. Silicon-rutile—Anultra-high pressure(UHP)mineral from an ophiolite. Progress in Natural Science, 13(7): 528-531. [27] Zack, T., Kronz, A., Foley, S., et al., 2002. Trace element abundances in rutiles from eclogites and associated garnet mica schists. Chem. Geol., 184: 97-122. doi: 10.1016/S0009-2541(01)00357-6 [28] Zack, T., Moraes, R., Kronz, A., 2004a. Temperature dependence of Zr in rutile: Empirical calibration of a rutile thermometer. Contr. Min. Petrol., 148: 471-488. doi: 10.1007/s00410-004-0617-8 [29] Zack, T., von Eynatten, H., Kronz, A., 2004b. Rutile geochemistry and its potential use in quantitative provenance studies. Sediment Geol., 171: 37-58. doi: 10.1016/j.sedgeo.2004.05.009 [30] 黄建平, 马东升, 刘聪, 等, 2002. 苏北超高压变质带榴辉岩型金红石矿床及其成因. 南京大学学报(自然科学版), 38(4): 514-524. doi: 10.3321/j.issn:0469-5097.2002.04.009 [31] 李秋立, 李曙光, 周红英, 等, 2001. 超高压榴辉岩中金红石U-Pb年龄: 快速冷却的证据. 科学通报, 46(19): 1655-1658. doi: 10.3321/j.issn:0023-074X.2001.19.016 [32] 凌文黎, 程建萍, 1999. Lu-Hf同位素体系对若干基础地质问题的新制约(之一)——地球早期演化. 地质科技情报, 18(1): 79-84. doi: 10.3969/j.issn.1000-7849.1999.01.016 [33] 宋衍茹, 金振民, 2002. 纳米级超高压相金红石——大陆深俯冲深度的示踪. 地学前缘, 9(4): 267-272. doi: 10.3321/j.issn:1005-2321.2002.04.006 [34] 王汝成, 王硕, 邱检生, 等, 2005. CCSD主孔揭示的东海超高压榴辉岩中金红石: 微量元素地球化学及其成矿意义. 岩石学报, 21(2): 465-474. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200502021.htm [35] 徐珏, 陈毓川, 王登红, 等, 2004. 中国大陆科学钻探主孔100~ 2 000 m超高压变质岩中的钛矿化. 岩石学报, 20(1): 19-26. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200401009.htm [36] 许志琴, 2004. 中国大陆科学钻探工程的科学目标及初步成果. 岩石学报, 20(1): 1-8. https://www.cnki.com.cn/Article/CJFDTOTAL-YSXB200401000.htm -
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