Geochemical Constraints on Fertile and Infertile Miocene Magmatic Suite in Dalli Area, Iran and Its Insights for Metallogeny
-
摘要: 伊朗乌尔米耶-达克塔尔弧岩浆带(Urumieh-Dokhtar magmatic arc, UDMA)是特提斯域最重要的斑岩铜矿省, 发育大量中新世大型超-大型斑岩铜矿床；同时, 该带也发育大量同时代无矿岩体, 但控制岩体成矿潜力的关键因素尚不清楚.为此, 选择该带中段、成矿及无矿岩体同时发育的大理矿区, 针对成矿及无矿岩体开展了系统的锆石岩相学、年代学、微量元素地球化学及Hf同位素地球化学对比.结果显示, 无矿闪长岩(锆石U-Pb年龄：17.4±0.3 Ma)比成矿石英闪长斑岩(锆石U-Pb年龄：15.6±0.1 Ma)形成略早, 但近乎同期；闪长岩εHf(t)值变化介于+2~+4, 石英闪长斑岩εHf(t)值变化介于+2~+5, 两者具有类似的Hf同位素组成；闪长岩中锆石常含老的继承核(172~920 Ma), 石英闪长斑岩则不发育继承锆石；闪长岩及石英闪长斑岩中的中新世锆石具有类似的稀土配分模式, 且Eu负异常不明显, 而闪长岩中的锆石继承核则显示出明显的Eu负异常, 配分模式与中新世锆石不同.基于上述结果, 我们提出大理矿区的两套中新世岩体具有相同的岩浆源区, 但经历了不同的地壳演化过程, 成矿的石英闪长斑岩浆形成后, 与古老地壳没有明显交互, 而无矿的闪长岩浆, 在上升过程中与地壳物质、特别是古老还原性物质发生了交互, 交互过程中岩浆氧逸度降低, 是该套岩浆不成矿的主要原因.进而我们提出UDMA带中段斑岩成矿与否不仅与前人所认为的受岩浆源区控制, 也与岩浆演化过程密不可分.Abstract: The Urumieh-Dokhtar magmatic arc (UDMA), hosting three giant and six large Miocene porphyry copper deposits, is the most important post collisional porphyry belt in the Tethyan domain. In the UDMA belt, there are also abundant coeval barren porphyry intrusions, but the factors controlling fertility of Miocene porphyry intrusions in the belt remains enigmatic. The Dalli deposit, located in the central segment of UDMA, contains both fertile and barren Miocene intrusions. In this study, we report zircon petrography, geochronology, trace element geochemistry and Hf isotopic compositions for the barren diorite and mineralization-related quartz diorite porphyry at Dalli. The results show that the diorite has inherited zircon cores overgrown by new zircons, whereas quartz diorite only has one type of zircon. The diorite yields a zircon U -Pb age of 17.4±0.3 Ma, which is slightly older than the quartz diorite porphyry (zircon U-Pb:15.6±0.1 Ma), and the inherited zircon cores yielded as zircon U-Pb of 172-920 Ma. Both the diorite and quartz diorite porphyry show slightly positive εHf(t) values, which are respectively +2-+4 and +2-+5.Miocene zircons from both diorite and quartz diorite porphyry are characterized by obviously positive Ce anomalies and slightly depleted Eu anomalies. However, the inherited zircon cores exhibit more depleted Eu anomalies, suggesting low oxygen fugacity. These results suggest that the barren diorite possibly interacted with ancient crust, particularly with reduced material, which subsequently decreased magma oxygen fugacity whereas the fertile quartz diorite porphyry emplaced without such material exchange. On the basis of above observations, we propose magma process may be the first order of key factors controlling the fertility of intrusions in the central segment of the UDMA.
-
Key words:
- Iran /
- Urumieh-Dokhtar magmatic arc /
- Dalli /
- porphyry copper deposits /
- magma evolution /
- petrology
-
图 1 伊朗UDAM带斑岩铜矿床分布及萨韦-亚兹德斑岩铜矿带(Saveh-Yazd porphyry copper belt，SYPCB)区域地质图
a.据Zarasvandi et al.(2005)，Boomeri et al.(2010)，Ayati et al.(2013)，Aghazadeh et al.(2015)修改；b图据Aghazadeh et al.(2015)修改
Fig. 1. Location of major porphyry Cu deposits and regional geologic map of Saveh-Yazd porphyry copper belt
图 2 伊朗UDMA中段大理矿区地质图
据Ayati et al., 2013 (修改)
Fig. 2. Geological map of the Dalli area in middle part of UDMA belt in Iran
图 3 大理矿区石英闪长斑岩(DA12-2-4)及闪长岩体(DA12-1-6)锆石阴极发光电子(CL)图像
Fig. 3. Cathodoluminescence (CL) images of zircons of the quartz diorite porphyry (DA12-2-4) and diorite (DA12-1-6) in Dal- li mining area
图 4 大理矿区石英闪长斑岩(DA12-2-4)及闪长岩体(DA12-1-6)锆石LA-ICP-MS U-Pb年龄谐和图
Fig. 4. Zircon U-Pb LA-ICP-MS concordia diagrams for the quartz diorite porphyry and diorite in the Dalli district, Iran
图 5 锆石球粒陨石标准化REE配分曲线图
球粒陨石REE数据据Sun and McDonough (1989)；Burnham and Berry(2012)
Fig. 5. Chondrite-normalized REE content diagrams of zircon
图 6 伊朗UDMA带锆石εHf(t)-U-Pb年龄图解
数据引自Chiu et al.(2017)；Asadi (2018)
Fig. 6. Plot of εHf(t) values versus U -Pb ages of zircons from the UDMA in Iran
-
Afshooni, S.Z., Mirnejad, H., Esmaeily, D., et al., 2013.Miner-al Chemistry of Hydrothermal Biotite from the Kahang Porphyry Copper Deposit (NE Isfahan), Central Prov-ince of Iran.Ore Geology Reviews, 54:214-232. https://doi.org/10.1016/j.oregeorev.2013.04.004 Agard, P., Omrani, J., Jolivet, L., et al., 2011.Zagros Orogeny:A Subduction-Dominated Process. Geological Maga-zine, 148(5-6):692-725. doi: 10.1017/S001675681100046X Aghazadeh, M., Hou, Z. Q., Badrzadeh, Z., et al., 2015. Temporal-Spatial Distribution and Tectonic Setting of Por-phyry Copper Deposits in Iran:Constraints from Zircon U-Pb and Molybdenite Re-Os Geochronology.Ore Geology Reviews, 70:385-406. https://doi.org/10.1016/j.ore-georev.2015.03.003 Alavi, M., 1980. Tectonostratigraphic Evolution of the Zagro-sides of Iran.Geology, 8(3):144-149. doi: 10.1130/0091-7613(1980)8<144:TEOTZO>2.0.CO;2 Alavi, M., 2004. Regional Stratigraphy of the Zagros Fold-Thrust Belt of Iran and Its Proforeland Evolution.Ameri-can Journal of Science, 304(1):1-20. https://doi.org/10.2475/ajs.304.1.1 Ali, S.A., Buckman, S., Aswad, K.J., et al., 2013.The Tecton-ic Evolution of a Neo-Tethyan (Eocene-Oligocene) Is-land-Arc (Walash and Naopurdan Groups) in the Kurdis-tan Region of the Northeast Iraqi Zagros Suture Zone.Is-land Arc, 22(1):104-125. https://doi.org/10.1111/iar.12007 Asadi, S., 2018.Triggers for the Generation of Post-Collision-al Porphyry Cu Systems in the Kerman Magmatic Cop-per Belt, Iran:New Constraints from Elemental and Iso-topic (Sr-Nd-Hf-O) Data.Gondwana Research, 64:97-121. https://doi.org/10.1016/j.gr.2018.06.008 Ayati, F., Yavuz, F., Asadi, H.H., et al., 2013.Petrology and Geochemistry of Calc-Alkaline Volcanic and Subvolca-nic Rocks, Dalli Porphyry Copper-Gold Deposit, Marka-zi Province, Iran. International Geology Review, 55(2):158-184. doi: 10.1080/00206814.2012.689640 Belousova, E., Griffin, W., O'Reilly, S. Y., et al., 2002. Igne-ous Zircon:Trace Element Composition as an Indicator of Source Rock Type. Contributions to Mineralogy and Petrology, 143(5):602-622. https://doi.org/10.1007/s00410-002-0364-7 Boomeri, M., Nakashima, K., Lentz, D. R., 2010. The Sarcheshmeh Porphyry Copper Deposit, Kerman, Iran:A Mineralogical Analysis of the Igneous Rocks and Altera-tion Zones Including Halogen Element Systematics Re-lated to Cu Mineralization Processes. Ore Geology Re-views, 38(4):367-381. https://doi.org/10.1016/j.ore-georev.2010.09.001 Burnham, A.D., Berry, A.J., 2012.An Experimental Study of Trace Element Partitioning between Zircon and Melt as a Function of Oxygen Fugacity.Geochimica et Cosmochi-mica Acta, 95:196-212. https://doi.org/10.1016/j.gca.2012.07.034 Chiu, H.Y., Chung, S.L., Zarrinkoub, M.H., et al., 2017.Zir-con Hf Isotopic Constraints on Magmatic and Tectonic Evolution in Iran:Implications for Crustal Growth in the Tethyan Orogenic Belt.Journal of Asian Earth Sciences, 145:652-669. doi: 10.1016/j.jseaes.2017.06.011 Chiu, H.Y., Chung, S.L., Zarrinkoub, M.H., et al., 2013.Zir-con U-Pb Age Constraints from Iran on the Magmatic Evolution Related to Neotethyan Subduction and Zagros Orogeny.Lithos, 162-163:70-87. doi: 10.1016/j.lithos.2013.01.006 Ghasemi, A., Talbot, C. J., 2006. A New Tectonic Scenario for the Sanandaj-Sirjan Zone (Iran). Journal of Asian Earth Sciences, 26(6):683-693. https://doi.org/10.1016/j.jseaes.2005.01.003 Haschke, M., Ahmadian, J., Murata, M., et al., 2010. Copper Mineralization Prevented by Arc-Root Delamination dur-ing Alpine-Himalayan Collision in Central Iran.Econom-ic Geology, 105(4):855-865. https://doi.org/10.2113/gsecongeo.105.4.855 Hezarkhani, A., Williams-Jones, A.E., 1998.Controls of Alter-ation and Mineralization in the Sungun Porphyry Copper Deposit, Iran; Evidence from Fluid Inclusions and Stable Isotopes. Economic Geology, 93(5):651-670. https://doi.org/10.2113/gsecongeo.93.5.651 Hoskin, P.W.O., Black, L.P., 2002.Metamorphic Zircon For-mation by Solid-State Recrystallization of Protolith Igne-ous Zircon. Journal of Metamorphic Geology, 18(4):423-439. https://doi.org/10.1046/j.1525-1314.2000.00266.x Kargaranbafghi, F., Neubauer, F., Genser, J., et al., 2012.Me-sozoic to Eocene Ductile Deformation of Western Cen-tral Iran:From Cimmerian Collisional Orogeny to Eo-cene Exhumation. Tectonophysics, 564-565:83-100. https://doi.org/10.1016/j.tecto.2012.06.017 Li, W.K., Yang, Z.M., Cao, K., et al., 2019.Redox-Controlled Generation of the Giant Porphyry Cu-Au Deposit at Pu-lang, Southwest China.Contributions to Mineralogy and Petrology, 174(2):12. https://doi.org/10.1007/s00410-019-1546-x Meyer, B., Mouthereau, F., Lacombe, O., et al., 2006. Evi-dence of Quaternary Activity along the Deshir Fault:Im-plication for the Tertiary Tectonics of Central Iran.Geo-physical Journal International, 164(1):192-201. https://doi.org/10.1111/j.1365-246x.2005.02784.x Mirnejad, H., Hassanzadeh, J., Cousens, B. L., et al., 2010. Geochemical Evidence for Deep Mantle Melting and Lithospheric Delamination as the Origin of the Inland Damavand Volcanic Rocks of Northern Iran. Journal of Volcanology and Geothermal Research, 198(3-4):288-296. doi: 10.1016/j.jvolgeores.2010.09.014 Morley, C. K., Kongwung, B., Julapour, A. A., et al., 2009.Structural Development of a Major Late Cenozoic Basin and Transpressional Belt in Central Iran:The Central Ba-sin in the Qom-Saveh Area. Geosphere, 5(4):325-362. https://doi.org/10.1130/ges00223.1 Mouthereau, F., Lacombe, O., Vergés, J., 2012. Building the Zagros Collisional Orogen:Timing, Strain Distribution and the Dynamics of Arabia/Eurasia Plate Convergence.Tectonophysics, 532-535:27-60. https://doi.org/10.1016/j.tecto.2012.01.022 Rowins, S.M., 2000.Reduced Porphyry Copper-Gold Depos-its:A New Variation on an Old Theme. Geology, 28(6):491-494. doi: 10.1130/0091-7613(2000)28<491:RPCDAN>2.0.CO;2 Shafiei, B., Haschke, M., Shahabpour, J., 2009. Recycling of Orogenic Arc Crust Triggers Porphyry Cu Mineraliza-tion in Kerman Cenozoic Arc Rocks, Southeastern Iran.Mineralium Deposita, 44(3):265-283. https://doi.org/10.1007/s00126-008-0216-0 Sillitoe, R.H., 2010.Porphyry Copper Systems.Economic Ge-ology, 105(1):3-41. https://doi.org/10.2113/gsecon-geo.105.1.3 Sun, S.S., McDonough, W.F.S., 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 Waterman, G. C., Hamilton, R. L., 1975. The Sar Cheshmeh Porphyry Copper Deposit. Economic Geology, 70(3):568-576. https://doi.org/10.2113/gsecongeo.70.3.568 Watson, E. B., Wark, D. A., Thomas, J. B., 2006. Crystalliza-tion Thermometers for Zircon and Rutile. Contributions to Mineralogy and Petrology, 151(4):413-433. https://doi.org/10.1007/s00410-006-0068-5 Wu, F. Y., Yang, Y. H., Xie, L. W., et al., 2006. Hf Isotopic Compositions of the Standard Zircons and Baddeleyites Used in U-Pb Geochronology. Chemical Geology, 234(1-2):105-126. https://doi.org/10.1016/j.chem-geo.2006.05.003 Yang, D.B., Xu, W.L., Pei, F.P., et al., 2009.Petrogenesis of the Paleoproterozoic K-Feldspar Granites in Bengbu Up-lift:Constraints from Petro-Geochemistry, Zircon U-Pb Dating and Hf Isotope. Earth Science, 34(1):148-164 (in Chinese with English abstract). Yang, Z.M., Hou, Z.Q., Song, Y.C., et al., 2008.Qulong Su-perlarge Porphyry Cu Deposit in Tibet:Geology, Altera-tion and Mineralization. Mineral Deposits, 27(3):279-318 (in Chinese with English abstract). Yu, C., Yang, Z.M., Zhou, L.M., et al., 2019.Impact of Laser Focus on Accuracy of U-Pb Dating of Zircons by LA-ICPMS. Mineral Deposits, 38(1):21-28 (in Chinese with English abstract). http://www.wanfangdata.com.cn/details/detail.do?_type=perio&id=kcdz201901002 Zarasvandi, A., Liaghat, S., Zentilli, M., et al., 2007.40Ar/39Ar Geochronology of Alteration and Petrogenesis of Porphy-ry Copper-Related Granitoids in the Darreh-Zerreshk and Ali-Abad Area, Central Iran.Exploration and Min-ing Geology, 16(1-2):11-24. https://doi.org/10.2113/gsemg.16.1-2.11-a Zarasvandi, A., Liaghat, S., Zentilli, M., 2005. Geology of the Darreh-Zerreshk and Ali-Abad Porphyry Copper Deposits, Central Iran. International Geology Review, 47(6):620-646. https://doi.org/10.2747/0020-6814.47.6.620 Zarasvandi, A., Rezaei, M., Raith, J., et al., 2015b.Geochemis-try and Fluid Characteristics of the Dalli Porphyry Cu-Au Deposit, Central Iran.JournalofAsian Earth Sciences, 111:175-191. https://doi.org/10.1016/j.jseaes.2015.07.029 Zarasvandi, A., Rezaei, M., Sadeghi, M., et al., 2015a. Rare Earth Element Signatures of Economic and Sub-Eco-nomic Porphyry Copper Systems in Urumieh-Dokhtar Magmatic Arc (UDMA), Iran.Ore Geology Reviews, 70:407-423. doi: 10.1016/j.oregeorev.2015.01.010 Zhang, H.R., Hou, Z.Q., 2015.Tectonic Evolution and Miner-alization of Zagros Orogenic Belt.Acta Geologica Sinica, 89(9):1560-1572 (in Chinese with English abstract). Zhang, Z., Song, J. L., Tang, J. X., et al., 2017. Petrogenesis, Diagenesis and Mineralization Ages of Galale Cu-Au De-posit, Tibet:Zircon U-Pb Age, Hf Isotopic Composition and Molybdenite Re-Os Dating. Earth Science, 42(6):862-880(in Chinese with English abstract). Zhao, Z.D., Liu, D., Wang, Q., et al., 2018.Zircon Trace Ele-ments and Their Use in Probing the Deep Processes.Earth Science Frontiers, 25(6):124-135(in Chinese with English abstract). 杨德彬, 许文良, 裴福萍, 等, 2009.蚌埠隆起区古元古代钾长花岗岩的成因:岩石地球化学、锆石U-Pb年代学与Hf同位素的制约.地球科学, 34(1):148-164. doi: 10.3321/j.issn:1000-2383.2009.01.014 杨志明, 侯增谦, 宋玉财, 等, 2008.西藏驱龙超大型斑岩铜矿床:地质、蚀变与成矿.矿床地质, 27(3):279-318. doi: 10.3969/j.issn.0258-7106.2008.03.002 于超, 杨志明, 周利敏, 等, 2019.激光焦平面变化对LA-ICPMS锆石U-Pb定年准确度的影响.矿床地质, 38(1):21-28. http://d.old.wanfangdata.com.cn/Periodical/kcdz201901002 张洪瑞, 侯增谦, 2015.伊朗扎格罗斯造山带构造演化与成矿.地质学报, 89(9):1560-1572. doi: 10.3969/j.issn.0001-5717.2015.09.002 张志, 宋俊龙, 唐菊兴, 等, 2017.西藏嘎拉勒铜金矿床的成岩成矿时代与岩石成因:锆石U-Pb年龄、Hf同位素组成及辉钼矿Re-Os定年.地球科学, 42(6):862-880. http://earth-science.net/WebPage/Article.aspx?id=3584 赵志丹, 刘栋, 王青, 等, 2018.锆石微量元素及其揭示的深部过程.地学前缘, 25(6):124-135. http://d.old.wanfangdata.com.cn/Periodical/dxqy201806011 -
dqkx-44-6-2187-Table.pdf
-
下载:
点击查看大图
图(6)
计量
- 文章访问数: 5149
- HTML全文浏览量: 1671
- PDF下载量: 54
- 被引次数: 0
