国外铁氧化物铜—金矿床的特征及其研究现状

doi:10.11867/j.issn.1001-8166.2003.04.0551

铁氧化物铜-金矿床是一类具许多共同特征但成因联系不太密切的矿床类型，近来已成为国外铜-金勘探的主要矿床类型之一。该类矿床以矿石中含有大量的铁氧化物（磁铁矿或赤铁矿）且伴有很强的区域性钠（-钙）质蚀变为特征，可以产于元古代克拉通内或新生代大陆边缘岛弧环境，其周围具火成岩或含蒸发盐层，时空上与之有关的侵入岩为磁铁矿系列花岗岩，矿化主要产于近区域主断裂的羽状次级断裂中。部分该类矿床的形成与一定的主岩类型有关，而多数矿床可能由高盐度 H₂O-CO₂-盐混合流体的不混溶作用形成，且矿化通常与钾化有关。对成矿流体是主要来自岩浆还是受围岩控制尚有争论，成矿模式有蒸发盐来源模式、外来流体加热模式和岩浆-热液流体模式。但对部分该类矿床详细的流体包裹体和稳定同位素研究表明成矿流体主要源于岩浆。对该类矿床进行地球物理勘探需要考虑磁铁矿、硫化物和Cu-Au矿化之间的相互关系。在我国开展对该类矿床的研究将有益于发现新的铜资源基地。

关键词: 铁氧化物铜-金矿床, 磁铁矿或赤铁矿, 钠（-钙）蚀变, 钾化, 岩浆-热液流体模式

The iron-oxide Cu-Au deposits is a class of loosely related ores that share a pool of common characteristics but no common genetic relationship, it has become one of the major targets of Cu-Au exploration industry over the last decade. This class of deposits is characterized by the abundance of iron oxide (magnetite or hematite) in the ores and the associated intensive regional sodic(-calcic) alteration. They may occur in Proterozoic intracraton or Phanerozoic continental margin volcanic arcs with nearby intrusive complex or evaporite. The spatially and temporally associated intrusive rocks are magnetite-series granitoids. Mineralization mainly occurs in second order echelon structures near the main regional structure. The mineralization of a number of deposits of this class were associated with certain types of host rocks, but the most were formed by the unmixing of H₂O-CO₂-salt fluid with very high salinities and the mineralization is commonly linked to potassic alteration. There is argument whether the fluids responsible for mineralization is a dominant magmatic source or controlled by host rocks. The main genetic models include “an evaporite source model”, “a fluid heating model” and “a magmatic hydrothermal model”. However, detailed fluid inclusion and stable isotope studies at several deposits have indicated a dominant magmatic component to the fluids responsible for mineralization. The sorts of relationships between magnetite, sulphides and Cu-Au mineralization in Fe-oxide Cu-Au systems should be considered in the geophysical exploration. To study this type of deposits will be helpful for the discovery of new Cu resources base in China.

Key words: Iron-oxide Cu-Au deposits, Magnetite or hematite, Sodic(-calcic) alteration, Potassic alteration, Magmatic-hydrothermal model.

中图分类号:

[1] Hitzman M W, Oreskes N, Einaudi M T. Geological characteristics and tectonic setting of Proterozoic iron oxide (Cu-U-Au REE)deposit [J]. Precambrian Research, 1992, 58: 241-287.

[2] Hitzman M W. Iron oxide copper-gold deposits: What, where, when and why [A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective[C]. Adelaide: AMF, 2000. 9-25.

[3] Craske T E. Geological aspects of the discovery of the Ernest Henry Cu-Au deposit, northwest Queensland [J]. Australian Institute of Geosciences Bulletin, 1995, 16: 95-109.

[4] Ryan P J, Lawrence A L, Jenkins R A, et al. The Candelaria copper-gold deposit, Chile [J]. Arizona Geological Society Digest, 1995, 20: 625-645.

[5] Pollard P J. Evidence of a magmatic fluid and metal source for Fe Oxide Cu-Au mineralisation [A]. In: Porter T M ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000:27-41.

[6] Pollard P J. Sodic-calcic alteration in Fe-oxide-Cu-Au districts: An originviaun mixing of magmatic H₂O-CO₂-NaCl±CaCl₂-KCl fluids [J]. Mineralium Deposita, 2001, 36: 93-100.

[7] Pollard P J, Mark G, Mitchell L C. Geochemistry of post-1540 Ma Granites in the Cloncurry District, northwest Queensland [J]. Economic Geology, 1998, 93:1 330-1 344.

[8] Perring C S, Pollard P J, Dong G, et al. The Lightning Creek sill complex, Cloncurry district, northwest Queensland: A source of fluids for Fe-oxide-Cu-Au mineralization and sodic-calcic alteation [J]. Economic Geology, 2000, 95: 1 067-1 089.

[9] Haynes D W, Cross K C, Bills R T, et al. Olympic Dam ore genesis: A fluid mixing model [J]. Economic Geology, 1995,90: 281-307.

[10] Barton M D, Johnson D A. Evaporitic-sourced model for igneous-related Fe-oxide-(REE-Cu-Au-U) mineralization [J]. Geology, 1996, 24: 259-262.

[11] Barton M D, Johnson D A. Alternative brine sources for Fe-Oxide(-Cu-Au) systems: Implications for hydrothermal alteration and metals [A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000:43-60.

[12] Reeve J S, Cross K C, Smith R N, et al. Olympic Dam copper-uranium-gold-silver deposit [A]. In: Hughes F E, ed. Geology of the Mineral Deposits of Australia and Papua New Guinea[C]. Melbourne: The Aus IMM, 1990.1 009-1 035.

[13] Haynes D W. Iron oxide copper (-gold) deposits: Their position in the ore deposit spectrum and modes of origin [A]. In: Porter T M ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000: 71-90.

[14] Ryan A J. Ernest Henry copper-gold deposit [A]. In: Berkman D A, Mackenzie D H, eds. Geology of Australian and Papua New Guinean Mineral Deposits [C]. Melbourne: The Australian IMM, 1998. 759-768.

[15] Marschik R, Leveille R A, Martin W. La Candelaria and the Puntadel Cobre District, Chile: Early Cretaceous iron-oxide Cu-Au(-Zn-Ag) mineralization [A]. In: Porter T M ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000.163-175.

[16] Frietsch R, Tuisku P, Martinsson O, et al. Early Proterozoic Cu (Au) and Fe ore deposits associated with regional Na-Cl metasomatism in northern Fennoscandia [J]. Ore Geology Reviews, 1997, 12: 1-34.

[17] Hildebrand R S. Kiruna-type deposits: Their origin and relationship to intermediate subvolcanic plutons in the Great Bear Magmatic Zone, northwest Canada [J]. Economic Geology, 1986, 81: 640-659.

[18] Espinoza S R, Veliz H G, Esquivel J L, et al. The cupriferous province of the Costal Range, northern Chile [A]. In: Camus E, Sillitoe R H, Peterson R, eds. Andean Copper Deposits: New Discoveries, Mineralisation, Styles and Metallogeny [C]. Society of Economic Geologists Special Publication No.5, 1996.19-32.

[19] Marschik R, Fontbote L. Copper (-iron) mineralization and super position of alteration events in the Puntadel Cobre belt, northern Chile [A]. In: Camus E, Sillitoe R H, Peterson R, eds. Andean Copper Deposits: New Discoveries, Mineralisation, Styles and Metallogeny [C]. Society of Economic Geologists Special Publication No.5, 1996. 171-190.

[20] Harris N B W. The Petrogenesis of alkaline intrusives from Arabia and northeast Africa and their implications for within-platemagmatism [J]. Tectonophysics, 1982, 83: 243-258.

[21] Keppler H, Wyllie P J. Partitioning of Cu, Sn, Mo, W, U and Th between melt and aqueous fluid in the systems haplogranite-H₂O-HCl and haplogranite-H₂O-HF [J]. Contributions to Mineralogy and Petrology, 1991, 109: 139-150.

[22] De Jong G, Williams P J. Giant metasomatic system formed during exhumation of mid crustal Proterozoic rocks in the vicinity of the Cloncurry Fault, NW Queensland [J]. Australian Journal of Earth Sciences, 1995, 42: 281-290.

[23] Rubenach M J, Barker A J. Metamorphic and metasomatic evolution of the Snake Creek Anticline, Eastern Succession, Mt IsaInlier [J]. Australian Journal of Earth Sciences, 1998, 45:363-372.

[24] Mark G. Albite formation by selective pervasive sodic alteration of tonalite plutons in the Cloncurry district, NW Queensland[J]. Australian Journal of Earth Sciences, 1998, 45: 765-774.

[25] Page R W, Sun S S. Aspects of geochronology and crustal evolution in the Eastern Fold Belt, Mt Isa Inlier [J]. Australian Journal of Earth Sciences, 1998, 45: 343-362.

[26] Houston D L, Bolger C, Cozens G. A comparison of mineral deposits at the Gecko and White Devil deposits: Implications for ore genesis in the Tennant Creek District, Northern Territory, Australia [J]. Economic Geology, 1993, 88: 1 198-1 225.

[27] Rotherham J F. A metasomatic origin for the iron-oxide Au-CuStarra orebodies, Eastern Fold Belt, Mount Isa Inlier [J]. Mineralium Deposita, 1997, 32: 205-218.

[28] Rotherham J F, Blake K L, Cartwright I, et al. Stable isotope evidence for the origin of the MesoProterozoic Starra Au-Cu de-posit, Cloncurry district, northwest Queensland [J]. Economic Geology, 1998, 93:1 435-1 449.

[29] Lindblom S, Broman C, Martinsson O. Magmatic-hydrothermal fluids in the Pahtohavare Cu-Au deposits in greenstone at Kiruna, Sweden [J]. Mineralium Deposita, 1996, 31: 307-318.

[30] Williams P J. Iron mobility during synmetasomorphic alteration in the Selwyn Range area, NW Queensland: Implications for the origin of ironstone-hosted Au-Cu deposits [J]. Mineralium Deposita, 1994, 29: 250-260.

[31] Baker T, Laing W P. Eloise Cu-Au deposit, east Mt Isa Block: Structural environment and structural controls on ore [J]. Australian Journal of Earth Sciences, 1998, 45: 429-444.

[32] Ullrich T D, Clark A H. The Candelaria copper-gold deposit, Region III, Chile: Paragenesis, geochronology and fluid composition [A]. In: Stanley, et al eds. Mineral Deposits: Processes to Processing [C]. Rotterdam: Balkema, 1999.201-204.

[33] Williams P J. Metalliferous economic geology of the Mt Isa Eastern Succession, Queensland [J]. Australian Journal of Earth Sciences, 1998, 45: 329-342.

[34] Mathur R, Marschik R, Ruit J, et al. Age of mineralization of the Cadelaria Fe oxide Cu-Au deposit and the origin of the Chilean iron belt, based on Re-Os isotopes [J]. Economic Geology, 2002, 97: 59-71.

[35] Reyes M. The Andacollo strata-bound gold deposit, Chile, and its position in a porphyry copper-gold system [J]. Economic Geology, 1991, 86:1 301-1 316.

[36] Dilles J H, Einaudi M T. Wall-rock alteration and hydrothermal flow paths about the Ann-Mason porphyry copper deposit, Nevada—A 6 km vertical reconstruction [J]. Economic Geology, 1992, 87: 1 963-2 001.

[37] Holloway J R. Fluid in the evolution of granitic magmas: Consequences of finite CO₂ solubility [J]. Geological Society of America Bulletin, 1976, 87: 1 513-1 518.

[38] Vidal C E, Injoque-Espinoza J, Sidder G B, et al. Amphibolitic Cu-Fe skarn deposits in the central coast of Peru [J]. Economic Geology, 1990, 85:1 447-1 461.

[39] Sillitoe R H. Characteristics and controls of the largest porphyry copper-gold and epithermal gold deposits in the circum-Pacific region [J]. Australian Journal of Earth Sciences, 1997, 44: 373-388.

[40] Adshead N D, Voulgaris P, Muscio V N. Osborne copper-gold deposit [A]. In: Berkman D A, Mackenzie D H, eds. Geology of Australian and Papua New Guinean Mineral Deposits [C]. Melbourne: The Australia IMM, 1998.793-799.

[41] Vila T, Lindsay N, Zamora R. Geology of the Manto Verdecopper deposit, Northern Chile: A specularite-rich, hydrother-mal-tectonic breccia related to the Atacama Fault Zone [A]. In: Camus E, Sillitoe R H, Peterson R, eds. Andean Copper Deposits: New Discoveries, Mineralisation, Styles and Metallogeny[C]. Society of Economic Geologists Special Publication No.5,1996.157-170.

[42] Reynolds L J. Geology of the Olympic Dam Cu-U-Au-Ag-REE deposit [A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000. 93-104.

[43] Wang S, Williams P J. Geochemistry and origin of Proterozoic skarns at the Mount Elliott Cu-Au(-Co-Ni) deposit, Cloncurry district, NW Queensland, Australia [J]. Mineralium Deposita, 2001, 36: 109-124.

[44] Li Zeqin, Hu Ruizhong, Wang Jiangzhen, et al. Lala Fe-Oxide Cu-Au-U-REE ore deposit, Sichuan China—An example of super imposed mineralizalization [ J ]. Bulletin of Mineralogy, Petrology and Geochemistry, 2002, 21(4): 258-260.[李泽琴,胡瑞忠,王奖臻,等.中国首例铁氧化物铜金铀—稀土型矿床的厘定及其成矿演化成[J].矿物岩石地球化学通报, 2002,21(4): 258-260.]

[45] Baker T. Alteration, mineralisation and fluid flow evolution at the Eloise Cu-Au deposit, Cloncurry district Northwest Queensland, Australia: Filtering key components in exploration models[J]. Economic Geology, 1998, 93: 1 213-1 236.

[46] Mark G, Oliver N H S, Williams P J, et al. The evolution of the Ernest Henry Fe-Oxide-(Cu-Au) hydrothermal system [A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000. 123-136.

[47] Williams P J, Skirrow R G. Overview of iron oxide-copper-gold deposits in the Curnamona province and Cloncurry district(Eastern Mount Isa Block), Australia [A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000. 105-122.

[48] Fortowski D B, McCracken S J A. Mount Elliot copper-gold deposit [A]. In: Berkman D A, Mackenzie D H, eds. Geology of Australian and Papua New Guinean Mineral Deposits [C]. Melbourne: The Australia IMM, 1998.775-782.

[49] Skirrow R G. Gold-copper-bismuth deposits of the Tennant Creek District, Australia: A reappraisal of diverse high-grade systems[A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective[C]. Adelaide: AMF, 2000.149-160.

[50] Souza L H, Vieira E A P. Salobo 3 Alpha deposit: Geology and mineralization [A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective[C]. Adelaide: AMF, 2000. 213-224.

[51] Ronze P C, Sores A D V, dos Santos M G S, et al. Alemao copper-gold(U-REE) deposit, Carajas, Brazil [A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000.191-202.

[52] Tazava E, de Oliveira C G. The Igarape Bahia Au-Cu-(REE-U) deposit, Carajas mineral province, Northern Brazil [A]. In: Porter T M, ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000. 203-212.

[53] Hopper D, Correa A. The Panulcillo and Teresa de Colmo copper deposits: Two contrasting examples of Fe-Ox Cu-Au mineralization from the Coastal Cordillera of Chile [A]. In: Porter TM ed. Hydrothermal Iron Oxide Copper-Gold & Related Deposits: A Global Perspective [C]. Adelaide: AMF, 2000.177-189.

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摘要

THE CHARACTERISTICS OF THE OVERSEAS IRON-OXIDE CU-AU DEPOSITS AND THE PRESENT SITUATION OF THE STUDIES