磁铁矿显微结构及化学成分对铜绿山矽卡岩型铜铁矿床成矿过程的指示

邵辉; 陈觅; 纪敏; 曾丽平

doi:10.3799/dqkx.2018.583

Volume 45 Issue 1

Jan. 2020

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Shao Hui, Chen Mi, Ji Min, Zeng Liping, 2020. Micro-Textures and Chemistry of Magnetite from the Tonglushan Skarn Cu-Fe Deposit and Its Implications for Ore-Forming Processes. Earth Science, 45(1): 118-130. doi: 10.3799/dqkx.2018.583

Citation:

Shao Hui, Chen Mi, Ji Min, Zeng Liping, 2020. Micro-Textures and Chemistry of Magnetite from the Tonglushan Skarn Cu-Fe Deposit and Its Implications for Ore-Forming Processes. Earth Science, 45(1): 118-130. doi: 10.3799/dqkx.2018.583

Citation:

Shao Hui, Chen Mi, Ji Min, Zeng Liping, 2020. Micro-Textures and Chemistry of Magnetite from the Tonglushan Skarn Cu-Fe Deposit and Its Implications for Ore-Forming Processes. Earth Science, 45(1): 118-130. doi: 10.3799/dqkx.2018.583

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Micro-Textures and Chemistry of Magnetite from the Tonglushan Skarn Cu-Fe Deposit and Its Implications for Ore-Forming Processes

doi: 10.3799/dqkx.2018.583

Shao Hui^{1
,
,},
Chen Mi^{2,3
,
,},
Ji Min²,
Zeng Liping²

1.
School of Earth Sciences, China University of Geosciences, Wuhan 430074, China
2.
Faculty of Earth Resources, China University of Geosciences, Wuhan 430074, China
3.
Geological Survey of Hubei Province, Wuhan 430034, China

Received Date: 2018-09-04
Publish Date: 2020-01-15

Abstract

Abstract

The Tonglushan skarn Cu-Fe polymetallic deposit is located in the Edongnan metallogenic province along the Middle and Lower Yangtze River belt. Orebodies are hosted in the contact zone between the Tonglushan pluton and the Triassic carbonate rocks. Magnetite is widespread in the deposit and is one of the ore minerals. In this study, representative hydrothermal magnetite samples were collected from the exoskarn and endoskarn, as well as the igneous magnetite from the host intrusion, for detailed analyses of microtextures and elemental compositions. The hydrothermal magnetite grains commonly have Ti-spinel exsolutions textures and Si-rich bandings, and were weakly metasomatized by late stage hydrothermal fluids. The presence of Ti-spinel exsolutions textures indicates that the ore-forming fluids of the Tonglushan deposit may have high contents of Ti initially. The hydrothermal magnetite also has relatively high contents of Si, Al, Cr, V, Mn, Mg, Co and Ni. Si⁴⁺, Al³⁺, Mg²⁺, Mn²⁺ were incorporated into magnetite by a mechanism of isomorphism. However, the mechanism and intensity of isomorphism in different types of magnetite are various, indicating that element substitution was affected by fluids compositions, pressure and temperature physicochemical conditions. Al₂O₃/MgO ratios are less than 4 in magnetite from exoskarn, vary from 5-8 in magnetite from endoskarn, and are around 13 for igneous magnetite. Igneous magnetite within intrusion has highest V₂O₃(on average 0.31%), magnetite within endoskarn has intermediate values(on average 0.14%), and magnetite from exoskarn has lowest V₂O₃ values(on average 0.01%-0.03%). The Al₂O₃/MgO ratios and V₂O₃ contents clearly demonstrate that growth of magnetite was affected by composition of melts/fluids, composition of country rocks, and fluid-rock interactions. The trend of decreased temperature for magnetite from the hosting intrusion, endoskarn, and exoskarn, and the trend of elemental compositions in Tonglushan deposit show that magnetite is a good indicator mineral for skarn deposit.
- skarn deposit,
- magnetite,
- microtexture,
- elemental composition,
- ore-forming processes,
- ore deposit

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References(45)

References

Dare, S. A. S., Barnes, S. J., Beaudoin, G., 2012. Variation in Trace Element Content of Magnetite Crystallized from a Fractionating Sulfide Liquid, Sudbury, Canada:Implications for Provenance Discrimination. Geochimica et Cosmochimica Acta, 88:27-50. https://doi.org/10.1016/j.gca.2012.04.032

Dare, S. A. S., Barnes, S. J., Beaudoin, G., et al., 2014. Trace Elements in Magnetite as Petrogenetic Indicators. Mineralium Deposita, 49(7):785-796. https://doi.org/10.1007/s00126-014-0529-0

Dare, S. A. S., Barnes, S. J., Beaudoin, G., 2015. Did the Massive Magnetite "Lava Flows" of El Laco (Chile) Form by Magmatic or Hydrothermal Processes? New Constraints from Magnetite Composition by LA-ICP-MS. Mineralium Deposita, 50(5):607-617. https://doi.org/10.1007/s00126-014-0560-1

Droop, G. T. R., 1987. A General Equation for Estimating Fe³⁺ Concentrations in Ferromagnesian Silicates and Oxides from Microprobe Analyses, Using Stoichiometric Criteria. Mineralogical Magazine, 51(361):431-435. https://doi.org/10.1180/minmag.1987.051.361.10

Dupuis, C., Beaudoin, G., 2011. Discriminant Diagrams for Iron Oxide Trace Element Fingerprinting of Mineral Deposit Types. Mineralium Deposita, 46(4):319-335. https://doi.org/10.1007/s00126-011-0334-y

Groves, D. I., Bierlein, F. P., Meinert, L. D., et al., 2010. Iron Oxide Copper-Gold (IOCG) Deposits through Earth History:Implications for Origin, Lithospheric Setting, and Distinction from other Epigenetic Iron Oxide Deposits. Economic Geology, 105(3):641-654. https://doi.org/10.2113/gsecongeo.105.3.641

Hu, H., Duan, Z., Luo, Y., et al., 2014. Trace Element Systematics of Magnetite from the Chengchao Iron Deposit in the Daye District:A Laser Ablation ICP-MS Study and Insights into Ore Genesis. Acta Petrologica Sinica, 30(5):1292-1306 (in Chinese with English abstract). http://d.old.wanfangdata.com.cn/Periodical/ysxb98201405008

Hu, H., Lentz, D., Li, J., et al., 2015. Reequilibration Processes in Magnetite from Iron Skarn Deposits. Economic Geology, 110(1):1-8. https://doi.org/10.2113/econgeo.110.1.1

Hu, H., Li, J. W., Lentz, D., et al., 2014. Dissolution-Reprecipitation Process of Magnetite from the Chengchao Iron Deposit:Insights into Ore Genesis and Implication for In-Situ Chemical Analysis of Magnetite. Ore Geology Reviews, 57:393-405. https://doi.org/10.1016/j.oregeorev.2013.07.008

Huang, X. W., Gao, J. F., Qi, L., et al., 2015b. In-Situ LA-ICP-MS Trace Elemental Analyses of Magnetite and Re-Os Dating of Pyrite:The Tianhu Hydrothermally Remobilized Sedimentary Fe Deposit, NW China. Ore Geology Reviews, 65:900-916. https://doi.org/10.1016/j.oregeorev.2014.07.020

Huang, X. W., Zhou, M. F., Qiu, Y. Z., et al., 2015a. In-Situ LA-ICP-MS Trace Elemental Analyses of Magnetite:The Bayan Obo Fe-REE-Nb Deposit, North China. Ore Geology Reviews, 65:884-899. https://doi.org/10.1016/j.oregeorev.2014.09.010

Huberty, J. M., Konishi, H., Heck, P. R., et al., 2012. Silician Magnetite from the Dales Gorge Member of the Brockman Iron Formation, Hamersley Group, Western Australia. American Mineralogist, 97(1):26-37. https://doi.org/10.2138/am.2012.3864

La Tourrette, T. Z., Burnett, D. S., Bacon, C. R., 1991. Uranium and Minor-Element Partitioning in Fe-Ti Oxides and Zircon from Partially Melted Granodiorite, Crater Lake, Oregon. Geochimica et Cosmochimica Acta, 55(2):457-469. https://doi.org/10.1016/0016-7037(91)90004-o

Li, J. W., Vasconcelos, P. M., Zhou, M. F., et al., 2014. Longevity of Magmatic-Hydrothermal Systems in the Daye Cu-Fe-Au District, Eastern China with Implications for Mineral Exploration. Ore Geology Reviews, 57:375-392. https://doi.org/10.1016/j.oregeorev.2013.08.002

Lin, S. Z., 1982. A Contribution to the Chemistry, Origin and Evolution of Magnetite. Acta Mineralogica Sinica, 2(3):166-174 (in Chinese with English abstract).

Liu, P. P., Zhou, M. F., Chen, W. T., et al., 2015. In-Situ LA-ICP-MS Trace Elemental Analyses of Magnetite:Fe-Ti-(V) Oxide-Bearing Mafic-Ultramafic Layered Intrusions of the Emeishan Large Igneous Province, SW China. Ore Geology Reviews, 65:853-871. https://doi.org/10.1016/j.oregeorev.2014.09.002

Nadoll, P., Angerer, T., Mauk, J. L., et al., 2014. The Chemistry of Hydrothermal Magnetite:A Review. Ore Geology Reviews, 61:1-32. https://doi.org/10.1016/j.oregeorev.2013.12.013

Nadoll, P., Mauk, J. L., Hayes, T. S., et al., 2012. Geochemistry of Magnetite from Hydrothermal Ore Deposits and Host Rocks of the Mesoproterozoic Belt Supergroup, United States. Economic Geology, 107(6):1275-1292. https://doi.org/10.2113/econgeo.107.6.1275

Nielsen, R. L., Forsythe, L. M., Gallahan, W. E., et al., 1994. Major- and Trace-Element Magnetite-Melt Equilibria. Chemical Geology, 117(1-4):167-191. https://doi.org/10.1016/0009-2541(94)90127-9

Ray, G. E., Webster, I. C. L., 2007. Geology and Chemistry of the Low Ti Magnetite-Bearing Heff Cu-Au Skarn and Its Associated Plutonic Rocks, Heffley Lake, South-Central British Columbia. Exploration and Mining Geology, 16(3/4):159-186. https://doi.org/10.2113/gsemg.16.3-4.159

Ryzhenko, B. N., Kovalenko, N. I., Prisyagina, N. I., 2006. Titanium Complexation in Hydrothermal Systems. Geochemistry International, 44(9):879-895. https://doi.org/10.1134/s0016702906090047

Shiga, Y., 1989. Further Study on Silician Magnetite. Mining Geology, 39:305-309. https://doi.org/10.11456/shigenchishitsu1951.39.217_305

Shimazaki, H., 1998. On the Occurrence of Silician Magnetites. Resource Geology, 48(1):23-29. https://doi.org/10.1111/j.1751-3928.1998.tb00004.x

Shu, Q. A., Chen, P. L., Cheng, J. R., 1992. The Geology of Iron and Copper Deposits in Eastern Hubei Province. Metallurgical Industry Press, Beijing (in Chinese).

Toplis, M. J., Corgne, A., 2002. An Experimental Study of Element Partitioning between Magnetite, Clinopyroxene and Iron-Bearing Silicate Liquids with Particular Emphasis on Vanadium. Contributions to Mineralogy and Petrology, 144(1):22-37. https://doi.org/10.1007/s00410-002-0382-5

Van Baalen, M. R., 1993. Titanium Mobility in Metamorphic Systems:A Review. Chemical Geology, 110(1-3):233-249. https://doi.org/10.1016/0009-2541(93)90256-i

Wang, P., 2008. Ore Petrology. China University of Geosciences Press, Wuhan (in Chinese).

Westendorp, R. W., Watkinson, D. H., Jonasson, I. R., 1991. Silicon-Bearing Zoned Magnetite Crystals and the Evolution of Hydrothermal Fluids at the Ansil Cu-Zn Mine, Rouyn-Noranda, Quebec. Economic Geology, 86(5):1110-1114. https://doi.org/10.2113/gsecongeo.86.5.1110

Williams, P. J., Barton, M. D., Johnson, D. A., et al., 2005. Iron Oxide Copper-Gold Deposits: Geology, Space-Time Distribution, and Possible Modes of Origin. In: Hedenquist, J. W., Thompson, J. F. H., Goldfarb, R. J., eds., Economic Geology, 100th Aniversary Volume, SEG, Denver, 371-405.

Xu, G. F., Shao, J.L., 1979. Standard Characteristics of Magnetite and Its Practical Significance. Geology and Prospecting, 3:30-37 (in Chinese).

Yu, Y. C., Xiao, G. Q., Li, G., 1985. Contact Metasomatic-Type Tonglvshan Iron-Copper Deposit in Daye County, Hubei Province. Geological Team of Southeast Hubei Province, Daye (in Chinese).

Zhai, Y. S., Yao, S. Z., Cai, K. Q., 2011. Mineral Deposit (Third Edition). Geological Publishing House, Beijing (in Chinese).

Zhao, H. J., Mao, J. W., Xie, G. Q., et al., 2010. Ore-Forming Fluids of the Tonglushan Copper-Gold Skarn Deposit, Hubei Province. Mineral Deposits, 29(S1):628-672 (in Chinese).

Zhao, H. J., Xie, G. Q., Wei, K. T., et al., 2012. Mineral Compositions and Fluid Evolution of the Tonglushan Skarn Cu-Fe Deposit, SE Hubei, East-Central China. International Geology Review, 54(7):737-764. https://doi.org/10.1080/00206814.2011.569418

Zhao, S. R., Bian, Q. J., Lin, Q. C., 2004. Crystallography and Mineralogy. Higher Education Press, Beijing (in Chinese).

Zhao, W. W., Zhou, M. F., 2015. In-Situ LA-ICP-MS Trace Elemental Analyses of Magnetite:The Mesozoic Tengtie Skarn Fe Deposit in the Nanling Range, South China. Ore Geology Reviews, 65:872-883. https://doi.org/10.1016/j.oregeorev.2014.09.019

胡浩, 段壮, Luo, Y., 等, 2014.鄂东程潮铁矿床磁铁矿的微量元素组成及其矿床成因意义.岩石学报, 30(5):1292-1306. http://d.old.wanfangdata.com.cn/Periodical/ysxb98201405008

林师整, 1982.磁铁矿矿物化学、成因及演化的探讨.矿物学报, 2(3):166-174. doi: 10.3321/j.issn:1000-4734.1982.03.002

舒全安, 陈培良, 程建荣, 1992.鄂东铁铜矿产地质.北京:冶金工业出版社.

王苹, 2008.矿石学教程.武汉:中国地质大学出版社.

徐国风, 邵洁涟, 1979.磁铁矿的标型特征及其实际意义.地质与勘探, 3:30-37.

余元昌, 肖国荃, 李刚, 1985.湖北省大冶县铜绿山接触交代铜铁矿床.大冶: 湖北省鄂东南地质大队.

翟裕生, 姚书振, 蔡克勤, 2011.矿床学(第三版).北京:地质出版社.

赵海杰, 毛景文, 谢桂青, 等, 2010.湖北铜绿山铜铁矿床成矿流体研究.矿床地质, 29(S1):628-672. http://d.old.wanfangdata.com.cn/Conference/7413216

赵珊茸, 边秋娟, 凌其聪, 2004.结晶学及矿物学.北京:高等教育出版社.

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