Titanite Chemical Compositions and Their Implications for Petrogenesis and Mineralization in Zhongdian Arc, NW Yunnan, China
-
摘要: 位于西南三江构造火成岩带义敦弧南段的中甸弧,以发育印支期斑岩型铜矿床和燕山期矽卡岩-热液石英脉型钼-钨-铜矿而著称.针对普朗、地苏嘎和休瓦促成矿岩体中的榍石单矿物,利用EMPA和LA-ICP-MS测定化学成分,探讨化学成分对成岩成矿的指示意义.普朗、地苏嘎和休瓦促岩体榍石均为岩浆来源.普朗岩体榍石形成温度为743~754℃,休瓦促岩体榍石形成温度为702~753℃.根据榍石的δCe、δEu推断三个岩体氧逸度高低顺序为:普朗>地苏嘎>休瓦促,榍石中的Cu含量对母岩浆中的Cu金属量变化不敏感,不能单独作为母岩浆Cu金属量的判别标志;钼成矿对岩体的氧逸度要求不高,在利用榍石中的Mo含量判断母岩浆中的Mo金属量时要综合考虑氧逸度和辉钼矿结晶的影响;岩体中的F含量能降低岩浆粘度,对钼成矿有促进作用,可以作为Mo成矿的指标;榍石中的W、Sn含量对Mo-W矿床具有指示作用,休瓦促Mo-W矿岩体中榍石的W、Sn含量要高于普朗和地苏嘎不成Mo-W矿的岩体.Abstract: Zhongdian arc is located in the southern section of the Yidun arc at the Sanjiang Tethys, Southwest China. It is known as the Indosinian porphyry copper deposits and the Yanshanian skarn-hydrothermal quartz vein Mo-W-Cu deposits. In this paper, it was measured the titanite chemical compositions from ore-forming rocks of Pulang, Disuga and Xiuwacu with EMPA and LA-ICP-MS to discuss their implications for petrogenesis and mineralization. The titanites from Pulang, Disuga and Xiuwacu are all of magmatic origin. The titanite formation temperature from Pulang pluton is 743-754 ℃, and 702-753 ℃ from Xiuwacu pluton. Based on the δCe, δEu from titanites, it can be inferred that the order of oxygen fugacity of these plutons is: Pulang > Disuga > Xiuwacu. It requires high magma oxygen fugacity for Cu mineralization, but the Cu contents in titanite are insensitive to the content variations of Cu in magma, which can not be used as an indication of the Cu contents in magma. Mo mineralization does not require high magma oxygen fugacity, and the magma oxygen fugacity and crystalization of molybdenite need to be thought when we use the Mo contents of titanite to determine the Mo fertility in magma. The F contents in magma can reduce magma viscosity and promote Mo mineralization which can be an indication for Mo mineralization. The W and Sn contents in the titanite is a good indication of the Mo-W mineralization, and the W and Sn contents in the Xiuwacu Mo-W deposit are higher than those in the Pulang and Disuga.
-
Key words:
- Yidun /
- Zhongdian arc /
- titanite /
- petrogenesis and mineralization /
- mineral deposit
-
图 1 东南亚构造单元划分简图(a)、义敦弧地质简图(b)和中甸弧地质简图(c)
图a中, YD.义敦弧;WB.西缅甸地块; SG.松潘-甘孜褶皱带; NLA.北拉萨弧; SQA:南羌塘弧; a.据Wang et al.(2014)修改; b.据Cao et al.(2019)修改; c.据Cao et al.(2019)修改
Fig. 1. The simplified diagram of structural units in Southeast Asia (a), the simplified geological maps of the Yindun arc (b) and the Zhongdian arc (c)
图 2 普朗、地苏嘎和休瓦促矿区地质简图
a.普朗矿区(据Cao et al., 2019修改); b.地苏嘎矿区(据刘学龙等, 2013修改); c.休瓦促矿区(据Yang et al., 2017修改)
Fig. 2. Geological map of Pulang, Disuga and Xiuwacu deposits
表 1 普朗、地苏嘎和休瓦促榍石EMPA测试结果
Table 1. The EMPA results of titanites from Pulang, Disuga and Xiuwacu
样号 F Al2O3 Na2O MgO SiO2 FeO MnO TiO2 CaO K2O P2O5 Total DSG⁃1 0.228 1.140 0.023 0.028 30.836 1.361 0.089 37.752 27.366 0.016 0.097 98.840 DSG⁃2 0.061 0.833 - 0.008 30.166 1.053 0.095 37.341 26.897 0.007 0.063 96.498 DSG⁃3 0.205 1.229 0.038 - 30.576 1.527 0.121 35.800 27.299 0.006 0.084 96.799 DSG⁃4 0.261 1.122 0.017 - 30.742 1.349 0.089 36.726 27.284 0.009 0.088 97.577 DSG⁃5 0.273 1.009 - 0.009 30.602 1.389 0.057 37.210 27.431 - 0.111 97.976 PL⁃1 0.086 1.149 - - 30.572 1.316 0.121 35.704 27.220 - 0.091 96.223 PL⁃2 0.240 1.045 - 0.003 30.501 1.335 0.013 36.704 27.440 - 0.104 97.284 PL⁃3 0.183 1.058 0.009 0.028 30.359 1.630 0.083 37.127 27.155 - 0.014 97.569 PL-4 0.294 1.125 - 0.002 30.521 1.362 0.089 38.176 27.398 - 0.120 98.963 PL⁃5 0.279 1.196 0.006 0.009 30.663 1.642 0.006 37.414 27.457 0.003 0.104 98.662 XWC⁃1 1.432 3.213 - 0.154 30.544 2.669 0.248 28.937 26.308 - - 92.902 XWC⁃2 1.391 3.880 0.029 0.175 30.249 3.476 0.457 26.999 25.507 0.002 0.018 91.597 XWC⁃3 1.285 3.315 0.053 0.177 29.643 3.252 0.344 29.010 25.723 0.009 0.009 92.279 XWC⁃4 1.229 3.221 - 0.134 30.371 3.041 0.218 30.795 26.091 - 0.072 94.655 XWC⁃5 1.575 3.332 - 0.160 30.185 2.921 0.513 30.521 26.107 - 0.037 94.688 注:“-”代表低于检测限,FeO为全铁含量;单位为%. 表 2 榍石Zr温度计计算结果
Table 2. Calculation results of Zr⁃in⁃titanite geothermometer
普朗石英二长斑岩榍石,
P=0.172 GPa休瓦促二长花岗岩榍石,
P=0.264 GPa样品号 Zr(10-6) T(℃) 样品号 Zr(10-6) T(℃) PL⁃01 598.1 744 XWC⁃01 512.6 746 PL⁃02 661.8 750 XWC⁃02 500.5 745 PL⁃03 703.4 753 XWC⁃03 225.8 702 PL⁃04 655.6 749 XWC⁃04 370.1 728 PL⁃05 590.2 743 XWC⁃05 466.7 741 PL⁃06 617.2 746 XWC⁃06 490.9 744 PL⁃07 624.4 746 XWC⁃07 455.6 740 PL⁃08 641.8 748 XWC⁃08 242.5 706 PL⁃09 669.5 750 XWC⁃09 578.6 753 PL⁃10 628.8 747 XWC⁃10 254.9 708 PL⁃11 659.4 749 XWC⁃11 501.3 745 PL⁃12 718.7 754 XWC⁃12 444.6 738 PL⁃13 607.0 745 XWC⁃13 293.0 716 平均值 748 平均值 732 -
[1] Aleinikoff, J.N., Wintsch, R.P., Fanning, C.M., et al., 2002.U-Pb Geochronology of Zircon and Polygenetic Titanite from the Glastonbury Complex, Connecticut, USA:An Integrated SEM, EMPA, TIMS, and SHRIMP Study.Chemical Geology, 188(1-2):125-147. https://doi.org/10.1016/s0009-2541(02)00076-1 [2] Audétat, A., 2015.Compositional Evolution and Formation Conditions of Magmas and Fluids Related to Porphyry Mo Mineralization at Climax, Colorado.Journal of Petrology, 56(8):1519-1546. https://doi.org/10.1093/petrology/egv044 [3] Audétat, A., Dolejš, D., Lowenstern, J.B., 2011.Molybdenite Saturation in Silicic Magmas:Occurrence and Petrological Implications.Journal of Petrology, 52(5):891-904. https://doi.org/10.1093/petrology/egr008 [4] Bachmann, O., Dungan, M.A., Lipman, P.W., 2002.The Fish Canyon Magma Body, San Juan Volcanic Field, Colorado:Rejuvenation and Eruption of an Upper-Crustal Batholith.Journal of Petrology, 43(8):1469-1503. https://doi.org/10.1093/petrology/43.8.1469 [5] Ballard, J.R., Palin, M.J., Campbell, I.H., 2002.Relative Oxidation States of Magmas Inferred from Ce(Ⅳ)/Ce(Ⅲ) in Zircon:Application to Porphyry Copper Deposits of Northern Chile.Contributions to Mineralogy and Petrology, 144(3):347-364. https://doi.org/10.1007/s00410-002-0402-5 [6] Cao, K., Yang, Z.M., Mavrogenes, J., et al., 2019.Geology and Genesis of the Giant Pulang Porphyry Cu-Au District, Yunnan, SW China.Economic Geology, 114(2):275-301. https://doi.org/10.5382/econgeo.2019.4631 [7] Cao, K., Yang, Z.M., Xu, J.F., et al., 2018.Origin of Dioritic Magma and Its Contribution to Porphyry Cu-Au Mineralization at Pulang in the Yidun Arc, Eastern Tibet.Lithos, 304-307:436-449. https://doi.org/10.1016/j.lithos.2018.02.018 [8] Cao, M.J., Qin, K.Z., Li, G.M., et al., 2015.In Situ LA-(MC)-ICP-MS Trace Element and Nd Isotopic Compositions and Genesis of Polygenetic Titanite from the Baogutu Reduced Porphyry Cu Deposit, Western Junggar, NW China.Ore Geology Reviews, 65:940-954. https://doi.org/10.1016/j.oregeorev.2014.07.014 [9] Carlier, G., Lorand, J.P., 2008.Zr-Rich Accessory Minerals (Titanite, Perrierite, Zirconolite, Baddeleyite) Record Strong Oxidation Associated with Magma Mixing in the South Peruvian Potassic Province.Lithos, 104(1-4):54-70. https://doi.org/10.1016/j.lithos.2007.11.008 [10] Celis, A., 2015.Titanite as an Indicator Mineral for Alkalic Porphyry Cu-Au Deposits in South-Central British Columbia (Dissertation).University of British Columbia, Columbia. [11] Che, X.D., Linnen, R.L., Wang, R.C., et al., 2013.Distribution of Trace and Rare Earth Elements in Titanite from Tungsten and Molybdenum Deposits in Yukon and British Columbia, Canada.The Canadian Mineralogist, 51(3):415-438. https://doi.org/10.3749/canmin.51.3.415 [12] Frost, B.R., Chamberlain, K.R., Schumacher, J.C., 2001.Sphene (Titanite):Phase Relations and Role as a Geochronometer.Chemical Geology, 172(1/2):131-148. https://doi.org/10.1016/s0009-2541(00)00240-0 [13] Gao, X., 2018.The Late Cretaceous Polymetallic Mineralization Related to Granitoid Systems in the Yidun Terrane, East Tibet (Dissertation).China University of Geosciences, Beijing (in Chinese with English abstract) [14] Giordano, D., Russell, J.K., Dingwell, D.B., 2008.Viscosity of Magmatic Liquids:A Model.Earth and Planetary Science Letters, 271(1-4):123-134. https://doi.org/10.1016/j.epsl.2008.03.038 [15] Graham, A.L., Ringwood, A.E., 1971.Lunar Basalt Genesis:The Origin of the Europium Anomaly.Earth and Planetary Science Letters, 13(1):105-115. https://doi.org/10.1016/0012-821x(71)90111-7 [16] Hayden, L.A., Watson, E.B., Wark, D.A., 2007.A Thermobarometer for Sphene (Titanite).Contributions to Mineralogy and Petrology, 155(4):529-540. https://doi.org/10.1007/s00410-007-0256-y [17] Henderson, P., 1980.Rare Earth Element Partition between Sphene, Apatite and Other Coexisting Minerals of the Kangerdlugssuaq Intrusion, E.Greenland.Contributions to Mineralogy and Petrology, 72(1):81-85. doi: 10.1007/BF00375570 [18] Higgins, J.B., Ribbe, P.H., 1976.The Crystal Chemistry and Space Groups of Natural and Synthetic Titanites.American Mineralogist, 61:878-888. http://www.researchgate.net/publication/237619745_The_crystal_chemistry_and_space_groups_of_natural_and_synthetic_titanites [19] Hou, Z.Q., Zaw, K., Pan, G.T., et al., 2007.Sanjiang Tethyan Metallogenesis in S.W.China:Tectonic Setting, Metallogenic Epochs and Deposit Types.Ore Geology Reviews, 31(1-4):48-87. https://doi.org/10.1016/j.oregeorev.2004.12.007 [20] Icenhower, J., London, D., 1996.Experimental Partitioning of Rb, Cs, Sr, and Ba between Alkali Feldspar and Peraluminous Melt.American Mineralogist, 81(5-6):719-734. https://doi.org/10.2138/am-1996-5-619 [21] Ismail, R., Ciobanu, C.L., Cook, N.J., et al., 2014.Rare Earths and Other Trace Elements in Minerals from Skarn Assemblages, Hillside Iron Oxide-Copper-Gold Deposit, Yorke Peninsula, South Australia.Lithos, 184-187:456-477. https://doi.org/10.1016/j.lithos.2013.07.023 [22] Kong, D.X., Xu, J.F., Chen, J.L., 2016.Oxygen Isotope and Trace Element Geochemistry of Zircons from Porphyry Copper System:Implications for Late Triassic Metallogenesis within the Yidun Terrane, Southeastern Tibetan Plateau.Chemical Geology, 441:148-161. https://doi.org/10.1016/j.chemgeo.2016.08.012 [23] Li, W.K., Yang, Z.M., Cao, K., et al., 2019.Redox-Controlled Generation of the Giant Porphyry Cu-Au Deposit at Pulang, Southwest China.Contributions to Mineralogy and Petrology, 174(2):1-34. https://doi.org/10.1007/s00410-019-1546-x [24] Liu, X.L., Li, W.C., Yin, G.H., 2013.Zircon U-Pb Age of Disuga Metallogenic Porphyries in Geza Island Arc, Yunnan Province, and Its Geological Significance.Geological Bulletin of China, 32(4):573-579(in Chinese with English abstract). http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=zgqydz201304005 [25] Liu, Y.S., Hu, Z.C., Gao, S., et al., 2008.In Situ Analysis of Major and Trace Elements of Anhydrous Minerals by LA-ICP-MS without Applying an Internal Standard.Chemical Geology, 257(1-2):34-43. https://doi.org/10.1016/j.chemgeo.2008.08.004 [26] Pan, L.C., Hu, R.Z., Bi, X.W., et al., 2018.Titanite Major and Trace Element Compositions as Petrogenetic and Metallogenic Indicators of Mo Ore Deposits:Examples from Four Granite Plutons in the Southern Yidun Arc, SW China.American Mineralogist, 103(9):1417-1434. https://doi.org/10.2138/am-2018-6224 [27] Pan, Y.N., 2017.Mineral Chemistry and Their Implications for Petrogenesis and Mineralization of the Ore-Bearing Porphyry in Zhongdian Arc in Northwestern Yunnan, China (Dissertation).China University of Geosciences, Beijing (in Chinese with English abstract). [28] Patten, C., Barnes, S.J., Mathez, E.A., et al., 2013.Partition Coefficients of Chalcophile Elements between Sulfide and Silicate Melts and the Early Crystallization History of Sulfide Liquid:LA-ICP-MS Analysis of MORB Sulfide Droplets.Chemical Geology, 358:170-188. https://doi.org/10.1016/j.chemgeo.2013.08.040 [29] Richards, J.P., 2003.Tectono-Magmatic Precursors for Porphyry Cu-(Mo-Au) Deposit Formation.Economic Geology, 98(8):1515-1533. https://doi.org/10.2113/98.8.1515 [30] Shi, H.Z., Fan, W.Y., Hu, Z.Z., et al., 2018.Geochronology and Geological Significance of the Pulang High-K Intermediate Acid Intrusive Rocks in the Zhongdian Area, Northwest Yunnan Province.Earth Science, 43(8):2600-2613(in Chinese with English abstract). http://d.old.wanfangdata.com.cn/Periodical/dqkx201808005 [31] Smith, M.P., Storey, C.D., Jeffries, T.E., et al., 2009.In Situ U-Pb and Trace Element Analysis of Accessory Minerals in the Kiruna District, Norrbotten, Sweden:New Constraints on the Timing and Origin of Mineralization.Journal of Petrology, 50(11):2063-2094. https://doi.org/10.1093/petrology/egp069 [32] Song, S.W., Mao, J.W., Xie, G.Q., et al., 2018.In Situ LA-ICP-MS U-Pb Geochronology and Trace Element Analysis of Hydrothermal Titanite from the Giant Zhuxi W (Cu) Skarn Deposit, South China.Mineralium Deposita, 54(4):569-590. https://doi.org/10.1007/s00126-018-0831-3 [33] Tiepolo, M., Oberti, R., Vannucci, R., 2002.Trace-Element Incorporation in Titanite:Constraints from Experimentally Determined Solid/Liquid Partition Coefficients.Chemical Geology, 191(1-3):105-119. https://doi.org/10.1016/s0009-2541(02)00151-1 [34] Wang, X.S., Bi, X.W., Leng, C.B., et al., 2014.Geochronology and Geochemistry of Late Cretaceous Igneous Intrusions and Mo-Cu-(W) Mineralization in the Southern Yidun Arc, SW China:Implications for Metallogenesis and Geodynamic Setting.Ore Geology Reviews, 61:73-95. https://doi.org/10.1016/j.oregeorev.2014.01.006 [35] Xie, L., Wang, R.C., Chen, J., et al., 2008.Primary Sn-Rich Titianite in the Qitianling Granite, Hunan Province, Southern China:An Important Type of Tin-Bearing Mineral and Its Implications for Tin Exploration.Chinese Science Bulletin, 54(5):798-805. https://doi.org/10.1007/s11434-008-0557-1 [36] Xu, L.L., Bi, X.W., Hu, R.Z., et al., 2014.LA-ICP-MS Mineral Chemistry of Titanite and the Geological Implications for Exploration of Porphyry Cu Deposits in the Jinshajiang:Red River Alkaline Igneous Belt, SW China.Mineralogy and Petrology, 109(2):181-200. https://doi.org/10.1007/s00710-014-0359-x [37] Yang, L.Q., Gao, X., Shu, Q.H., 2017.Multiple Mesozoic Porphyry-Skarn Cu (Mo-W) Systems in Yidun Terrane, East Tethys:Constraints from Zircon U-Pb and Molybdenite Re-Os Geochronology.Ore Geology Reviews, 90:813-826. https://doi.org/10.1016/j.oregeorev.2017.01.030 [38] Yang, X.M., 2017.Estimation of Crystallization Pressure of Granite iIntrusions.Lithos, 286-287:324-329. https://doi.org/10.1016/j.lithos.2017.06.018 [39] Yu, H.J., Li, W.C., 2016.Geochronology and Geochemistry of Xiuwacu Intrusions, NW Yunnan:Evidences for Two-Period Magmatic Activity and Mineralization.Acta Petrologica Sinica, 32(8):2265-2280(in Chinese with English abstract). http://d.old.wanfangdata.com.cn/Periodical/ysxb98201608003 [40] Zhou, F., Wang, B.D., Liu, H., et al., 2018.Zircon U-Pb Dating, Geochemistry and Petrogenesis of Intrusive Rocks from A're Area, Zhongdian Arc.Earth Science, 43(8):2614-2627 (in Chinese with English abstract). http://d.old.wanfangdata.com.cn/Periodical/dqkx201808006 [41] 高雪, 2018.义敦地体晚白垩世与侵入岩有关的多金属成矿作用(博士学位论文).北京: 中国地质大学. [42] 刘学龙, 李文昌, 尹光侯, 2013.云南格咱岛弧地苏嘎成矿岩体LA-ICP-MS锆石U-Pb年龄及地质意义.地质通报, 32(4):573-579. doi: 10.3969/j.issn.1671-2552.2013.04.005 [43] 潘彦宁, 2017.滇西北中甸弧含矿斑岩中矿物化学特征及其成岩成矿标识(硕士学位论文).北京: 中国地质大学. [44] 石洪召, 范文玉, 胡志中, 等, 2018.滇西北普朗铜矿床高钾中-酸性侵入岩年代学及其地质意义.地球科学, 43(8):2600-2613. doi: 10.3799/dqkx.2018.308 [45] 余海军, 李文昌, 2016.滇西北休瓦促Mo-W矿区印支晚期和燕山晚期岩浆活动与成矿作用:来自锆石U-Pb年代学和地球化学的证据.岩石学报, 32(8):2265-2280. http://www.cnki.com.cn/Article/CJFDTotal-YSXB201608003.htm [46] 周放, 王保弟, 刘函, 等, 2018.中甸弧阿热岩体锆石U-Pb年龄、地球化学特征及岩石成因.地球科学, 43(8):2614-2627. doi: 10.3799/dqkx.2018.126 -
dqkx-45-6-1999-Table1.pdf