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Technical Journal of Engineering and Applied Sciences Available online at www.tjeas.com ©2015 TJEAS Journal-2015-5-1/172-181 ISSN 2051-0853 ©2015 TJEAS Investigated the occurrence of iron ore, magnetite, carbonate sediments in the Oligocene North Bijar(NW of Iran) Maryam Ahankoub1, Fariba Jamshidi2, Reza sheikhi2 1. Assistance professor, Department of geology, Faculty of science, Payam- Noor University, Iran. 2. Department of geology, Faculty of science, Payam- Noor University, Iran Corresponding author email: [email protected] ABSTRACT: Studied area is located in NW of Central Iran Zone in Kurdistan Province, west of Shahrak City. There are High potassic to Shoshonitic intrusion bodies of Miocene consisting of granite, diorite, monzodiorite, and syenite that have been intruded into the sequence of Oligocene carbonate rocks. Petrography of these rocks show that maior minerals are plagioclas, pyroxen, biotite, olivine, hornbland, feldspar potasic and quartz. Geochemical investigation of the intrusion bodies show that it has been formed in Continental arc tectonic setting. The intrusion of igneous rocks into the carbonate formation has caused occurrence Ca and Mg skarnes with Iron mineralization. Shahrak Iron minerals have precious ore deposit because of the Iron̕ s High alloy, low amount of S, P and also Iron̕ s high reserve. Main ore deposit is iron with an average of 65 % with a small percentage (less than 5%) of sulfide minerals of pyrite and chalcopyrite. Also there is no accessory mineral such as Cu and Au. Key words: Iron Ore, Ca and Mg Skarn, Magnetite, Shahrak deposit, Kurdistan INTRODUCTION North Bijar skarn iron deposite is iron skarn with large store and valuable. Skarns are formed of Mg, Al and Fe silicates minerals that resulting by metasomatism of the limestone and dolomite rocks and Replacement of Si, Fe and Mg. Skarns, on the base of the conditions and How to formation, were divided to two groups, the reaction skarns and Skarnoides (Einaudi, 1981). Considering the importance of economic reserves of metals such as iron in countries development, study and investigation about metal potential is very important. In recent years, there has been done extensive investigation about pre-feasibility studies, detailed design and description exploration studies of the iron deposit. Following the conclusion of the contract of the Iran Steel Factory about Fe exploration, Iran Barite Company have been investigate about discovery of the iron ore deposits and were identified three zone including: a) Kerman - Bandar Abbas , B ) Khorasan , and c )Zanjan _ Hamedan . The first report, about geological and iron mineralization in shahrak area, was presented by Pey Company in 1978(Sheikhi, 1996). After licens issuing of exploration, was prepared geological-mining map and then was drilled wells and boreholes. Finally exploitation of Shahrak mine began in early 1994(Sheikhi, 1996). Today Shahrak skarn Iron deposite is one of the largest deposits of Fe mines in the NW of the Iran, that was utilize with storage of more than 20 million tones and over 50 m thickness. In this study, we present new geochemistry data about ores and country rocks from the Shahrak skarn iron deposit. Based on the results, we evaluate the source of ore-forming materials, and the geodynamic setting of ore genesis. Geological setting The study area is located in the NW of Iran in Kurdestan province in part of Zanjan West Mountain. Zanjan West Mountain is small part of the Soltanieh - Misho zone (Eftekharnzad, 1359) that base on the structure geological divisions is located in central Iran zone. The major lithological units of the Shahrak are composed of Tech J Engin & App Sci., 5 (1): 172-181, 2015 mezozoic metamorphic and sedimentary rocks units, and Cenozoic magmatic intrusions. The basement mainly consists of the skarn iron deposits of Shahrak are located within the periphery of the west of Central Iran. Regionally, the rocks in this area are dominated by sedimentary, metamorphic and igneous rocks. The rock units oldest consists of metamorphosed shale, limestone and dolomites, with andesite bands that is covered by Eocene volcanogenic thick layer sediments (conglomerate, sandstone, tuff and siltstone). Limestone Oligocene to early Miocene was formed in low deep marine environment that is covered by Quaternary alluvial subsequently. The most important deposits of iron has occurred as mass or dispersed within metamorphosed carbonate formations of Oligocene (Figure 1). Figure 1. geological map 1/20000 simplified the study area The Shahrak Iron deposits have been located as strataform, lens, massive, disseminated, granoblast and layer in limestone and dolomite Oligocene. The dominant basement rocks in this region are the Mesozoic rocks, intruded by Cenozoic plutons comprising mostly of monzonite, monzodiorite, and diorite, and quartz–diorite, granite, syenite. The genesis of these intrusions has been due to the subduction of the Paleo-thetys (Shaikhi, 1996). The major sedimentary unit in the mine is the Oligocen limestone. The main ore-controlling structure in the mine is an anticline trending NW. The ore bodies typically occur at the contact zones of the intrusion bodies and the limestone. From the contact zone profile, the shape of the ore bodies is reconstructed as complex lenses with end-to-end discontinuity. The serrated and interspersed features of the ore bodies are visible near their edges, with both inward and outward contact zones. Field studies reveal a close relationship between the diorite, which at some places grades to diorite porphyrite or monzodiorite, and the formation of the skarn and ores. Alteration zones are clearly developed at the contact of the intrusive with the surrounding limestone, and these zones can be divided into altered diorite zone, the endoskarn zone, the magnetite zone, the exoskarn zone and the marble zone. In general, the endoskarn zone shows a wider distribution as compared to the exoskarn zone which is narrow. The skarn mineral compositions basically include diopside, tremolite, actinolite, phlogopite, talc, garnet, and epidote. The marble at the external contact zone often has been brecciated or altered by chlorite. The main metallic minerals are magnetite, and a small amount of hematite, chalcopyrite, and pyrite. The content of magnetite in the ores varies from 55 to 75%. The subhedral to anhedral coarse magnetite grains range from 0.15 to 0.4 mm in size. Under the influence of late hydrothermal alteration, the magnetite grains are replaced by pyrite, calcite, and hematite, with the relict texture preserved in many cases. The pyrite is subhedral to idiomorphic and generally ranges in content from 1 to 2%, and sometimes up to 5% in some domains. Mineralogical and lithological There is diversity of lithological composition in the study area, including 173 Tech J Engin & App Sci., 5 (1): 172-181, 2015 Petrology and mineralogy intrusive bodies Intrusive rocks has outcrop as large masses, dikes and small bodies that Petrographic and lithological study has been done as follows: Granites almost are coarse to medium granular including to 30% Qtz with 0.2 to 1 mm, 40 to 45 % hypidiomorphic pertite with dimension to 2 mm, to7% plagioclase crystals with dimensions of to 2 mm with albite twining, up 5% Or with dimensions of 1 mm. The pyroxene crystals are 15 to 20 %t to mafic crystals with dimensions up to 1 mm, (Fig. 2a). Granodiorite are bright color and porphyry texture. There are major minerals 20% K-feldspar phenocrysts (0.5 to 1 mm), fine grain 60% plagioclase (< 0.3 mm) and 2%quartz (Fig. 2B). Diorite are gray color and texture intergranular, which contain 60% plagioclase, and 30% prismatic crystals of amphibole (Fig. 2 C). Monzodiorite almost has outcrop in North West - South East area with gray color. The rocks are mediumto coarse-grained, with plagioclase, K-feldspar and Pyroxene as the major mineral phases and magnetite, zircon, apatite, titanite and allanite as common accessory phases. Syenite are gray to pink color body with well-defined magmatic textures. K-feldspar is often pertite. (Figure 2 d). Skarn mineralogy There were formed skarn by injected of the Intrusions into carbonate rocks (limestone and dolomite) Oligocene and has created diversity skarns. According to the skarns classification by (Einaudi, 1981), both endoskarns and exoskarns can be identified in the region. Two-stage progressive metamorphism and two-stage retrograde metamorphism is distinguished in the skarn zone. First stage is formed garnet, phlogopite, and pyroxene, and in the second is formed stage amphibole, talc, calcite and chlorite. There are some minerals such as actinolite, chlorite, sericite, calcite, quartz and garnet in endoskarn. Main part of the skarn is exoskarn that has diffrent thickness from 5 to 20 m and is located between crystalline limestone and endoskarn. There are observed different skarns zone including garnet skarn, pyroxene skarn, amphibole skarn, plagioclase skarn, talc skarn and phlogopite skarn. Figure 2. A): phenocrysts of feldspar potassic with quartz crystals in granite, B): Am and Plag in granodiorite, C): Px, Am and plage in the diorite, D) the granular texture of feldspar potassic and in syenite, (Kretz, 1983). 174 Tech J Engin & App Sci., 5 (1): 172-181, 2015 Garnet skarn with to have 5 m thickness is the closest skarn zone to iron ore deposite. There are paragenesis mineralogy including garnet (grossular and andradite), chlorite, calcite and magnetite (Figure 3A). Garnet is often zoned and may reach more than 80% volume in some samples and has andradite composition in central that surrounded by grossular. Pyroxene skarn: is up 10 m thick that contain pyroxene (diopside and Hedenbergite) Along with the chlorite, albite, epidote, amphibole and magnetite. Secondary minerals, chlorite, actinolite and epidote occur as alteration products of pyroxene. (Fig. 3B). Amphibole skarn is large extended. There are tremolite, actinolite and pyrite crystals as Mineralogy paragenesis. actinolite green crystals was formed broom and filament texture of the up to 3 mm that comprises up to 70% volume of rock. There is chlorite as actinolite alteration often to 15% (Fig. 3 c, d). phlogopite skarn contain coarse grain green phlogopite and Magnetite. There are paragenesis of the minerals such as calcite, diopside, epidote, amphibole, and pyrite. Talc skarn with small extended, is often in the southern study area. Studies of core drilling indicate that this zone is located at deep. These rocks are green with soap tactility that has magnetite, talc, phlogopite, Pyrophilite as milnerlaogy paragenesis. Plagioclase skarn is close to intrusion bodies and there are forms 35-40 percent plagioclase, quartz, 5-10%, 10-15% and 45% magnetite and chlorite as mineralogical paragenesis . Figure 3. A): Garnet zoning (andradite in the center, grossular in the margin) in garnet skarn, B): px and magnetite in pyroxene skarn, C): Am in amphibole skarn, D): coarse Act in amphibole skarn, (Kretz, 1983). 175 Tech J Engin & App Sci., 5 (1): 172-181, 2015 Mineralization Iron mineralization occurred in adjacent intrusive and over metamorphosed carbonate formations. Magnetite is the most abundant of the constituent in ore deposits and has vast exposure in the superficial and deep parts of the region. The ore zone consists of discontinuous that there is 55 to 75 % magnetite in mineralization zone. These ore deposit has high economic value because iron high content, low content sulfur and phosphorus. Magnetite is developed idiomorphically. It is characterized by simple crystallographic forms: (111), (110) and (110) or their combinations. Individuals of magnetite are of considerable size, appearing like porphyroblasts (idioblasts) in a fine-grained mass of other ore and gangue minerals. Size varies on average between 1 and 10 mm. There is replacement or granular texture. In Large part of the gang occure martitized. (Ramdhor, 1980) believes that magnetite was affected by the influx of low temperature fluids and change to hematite along cleavage. Magnetite mineralization is part of skarns zone that were formed by solution of iron-rich. Some evidence for the presence of the solutions is consisting: Magnetite is most important Fe minerals. There are skarn minerals such as garnet, actinolite, phlogopite, talc and diopside with magnetite. Magnetite crystals were formed as crystalline and massive. Ore deposit is located within the skarn zone. We are classified mineralization zone based on the paragenesis that consisting of: 1 - Magnetite upper zone (Fig. 4A), 2 – oxide zone (Fig. 4B) and 3 - Magnetite lower zone (Fig. 4 c, d). In table 1 have been shown to separation of the three types of iron ore deposit zone. There are sulfide minerals such as pyrite 5%, chalcopyrite (up 2 percent), and iron oxides hematite and goethite. Pyrite Subidiomorphic to amorphous crystals have been found with dimensions less than 1 mm that main texture is observed often as scattered and fillers between of granular magnetite, cavities, fractures and boundaries of magnetite crystals. According to the pyrite formation low temperature, and its presence in the study area, pyrite was formed after magnetite. Figure 4. A): Magnetite in the upper zone, B): conversion of magnetite to hematite in the oxide zone, C and D): Pyrite in magnetite margin 176 Tech J Engin & App Sci., 5 (1): 172-181, 2015 Chalcopyrite has been found (with a frequency of <2%) as fine crystal less than 0.5 mm, often filling the empty space in the margins of magnetite, pyrite and quartz gangue. That was formed in final stage of retrograde metamorphic and related to the sulfide mineralization. In Table 2 are shown minerals paragenetic relations. There has occurred some progressive and retrograde alteration that is given as follows: Progressive metamorphism – metasomatism stage: This stage has occurred after emplacement of the intrusive rocks in the vicinity of impure carbonate formations during metamorphism and then was formed anhydrous silicate minerals of the fine-grained garnet, pyroxene and phlogopite. Progressive stages of metasomatism: This stage has ocuured by arrival of magmatic hydrothermal fluids into the host rock and formation of the anhydrides silicate minerals such as coarse garnet and pyroxene. Garnet and pyroxene formation temperature is about 450 to 650 ° C (Rose and Burt, 1979). Al was added to the host rock by hydrothermal solutions (Einaudi, 1982a). Garnet was formed by combination calcium, iron and hydrothermal silica. There are andradite, hedenbergite and magnetite by, mouth of high FeO and lack of silica (Deer and et al, 1962) 2Fe2O3 + 2FeO +5 SiO2 + 4CaCO3 = Ca3Fe2Si3O12 + CaFeSi2O6 + Fe3O4 + 4CO2 According to the lack of wollastonite, there is SiO 2/Fe2O3 <3 (Deer and et al, 1962). There is not exchange of wollastonite - magnetite or hedenbergite- wollastonite, which was shown garnet zone was formed in less than 650 °C. Table 1. Zone of Shahrak ore deposits Clay Minerals Kaolinite - Oxides minerals Hematite, Martite,Geothite,Limonite ، - Els minerlas Fe/ FeO 4.6 Hematite, Limonite,Geotite, Martite ، Pyrite, ، pyrotite 5.48 2.3 S 15%< 15%< 15%< Sulfid minerals Pyrite Pyrite, Pyrothite ، Fe- alloy Major minerals Magnetite>80% Magnetite Zone Upper magnetite Oxide Magnetite Lower magnetite Ore deposite type 68%< Magnetite 45-65% Magnetite 45-55% Magnetite Magnetite(A) - Magnetite )B( Martite - Magnetite (C) Martite Table 2) Paragenetic diagram of the minerals existing in Shahrak area 177 Tech J Engin & App Sci., 5 (1): 172-181, 2015 Figure 5. diagram Log fO2- T (Taylor and liou, 1978) to represent the range of stability of minerals in skarn paragenesis in Shahrak Early retrograde alteration stage that was formed hydrolysis process and occurred alteration of the garnet to quartz, magnetite, hematite, epidote, and pyroxene. Based on the formula provided by (Lentz et al, 1995), coexist magnetite and andradite Hedenbergitet (± quartz and calcite), can be explained by the following equation. CaFeSi2O6 + Ca3Fe2Si3O12 + 4CO2 = 4CaCO3 + Fe3O4 + 5SiO2 Usually magnetite, calcite and quartz are result of alteration andradite by decreasing temperature and increases of the fugacity. 3Ca3Fe2Si3O12 + 9CO2 = 9CaCO3 + 9SiO2 + ½ O2 + 2Fe3O4 The Beginning of garnet-epidote alteration was occurred in less than 450 C .Replacement of calcite, quartz and magnetite instead of andradite is an important retrograde reactions that occurs at low sulfide relatively condition in andradite skarn (Deer and et al, 1962). Late Retrograde stage there were formed are comprised of fine-grained chlorite, calcite, quartz and clay minerals by alteration hydrous and anhydrous calcareous silicate minerals by low-temperature fluids. Physicochemical conditions of skarn formation That indicates shahrak skarn is Ca-Mg skarn that contains phlogopite and talc (Taylor and Liou, 1978). On the base of Paragenetic diagrams (Taylor and Liou, 1978) and. Stability limits mineralogy paragenesis state that anhydrous minerals such as garnet and pyroxene was altered in 450 t0 650 C with oxygen fugacity 23-10 to 27-10 belongs. Geochemistry of intrusion bodes There is result of analyses 15 samples by XRF in table 3. Table 3. Data of the XRF analyzes 15 samples of intrusion bodies Shahrak Samples syenite syenite syenite diorite diorite diorite monzodiorite monzodiorite monzodiorite granodiorite granodiorite granodiorite granite granite granite SiO2 58.6 59.86 59.71 56.99 56.86 56.26 60.71 61.84 59.79 65.53 66.1 71.23 71.92 72.09 72.12 TiO2 0.72 0.75 0.76 0.72 0.67 0.71 0.75 0.73 0.71 0.61 0.75 0.68 0.71 0.65 0.71 Al2O3 15.11 14.78 14.91 15.78 15.8 16.11 18.02 18.04 18.07 15.43 15.74 14.96 14.83 14.98 14.85 Fe2O3 4.61 5.52 5.68 7.28 6.19 6.46 5.52 5.6 5.31 3.61 3.54 3.56 0.97 0.77 0.81 MnO 0.153 0.148 0.147 0.149 0.151 0.145 0.19 0.17 0.16 0.152 0.155 0.145 0.146 0.145 0.156 MgO 2.73 2.71 2.98 5.73 5.32 5.45 3.49 2.97 3.02 2.28 1.92 1.86 0.73 0.97 0.83 CaO 3.51 2.73 3.18 6.17 6.22 6.07 4.51 4.5 5.28 3.26 3.31 2.37 1.35 1.22 1.11 Na2O 4.5 5.4 5.42 3.07 2.51 2.63 4.02 3.82 4.01 3.97 4.12 3.21 3.34 4.14 4.15 K2O 5.12 5.31 5.31 2.56 2.29 2.17 3.58 3.16 3.93 2.81 3.54 3.89 5.09 5.23 5.98 P2O5 0.23 0.21 0.26 0.27 0.38 0.19 0.15 0.28 0.29 0.21 0.28 0.38 0.22 0.24 0.23 total 95.28 97.42 98.36 98.72 96.39 96.20 100.94 101.11 100.57 97.86 99.46 102.29 99.31 100.44 100.95 178 Tech J Engin & App Sci., 5 (1): 172-181, 2015 Plotting the data in the diagram R1-R2 (De La Roche and et al, 1980) and the diagram Na2O + K2O versus SiO2 proposed (Middelmost, 1985) revealed the variety of granite, diorite, granodiorite, monzonite to monzodiorite and syenite rocks (Figure 6 A and B). The diagram FeO / MgO vs. SiO2 (Miyashiro, 1974) show belong to an alkalic serie (7 a). The in the diagram SiO2 vs. K2O (Peccerillo and Taylor, 1976), display the range of K-rich calcalkaline to shoshonitic (Fig. 7 B). Whereas in the A/NK vs. A/CNK (Maniar and Piccoli, 1989), Shahrak sample are, are metaluminous or weakly peraluminous (Fig. 7 c). Diagrams of the samples Geodynamic position displays to belong to continental arc basalts (Mullen, 1983; Pearce and Cann, 1973) (Fig. 8 A and B). Figure 6. R2-R1 and Na2O+K2O-SiO2 (De La Roche and et al, 1980; Middlemost, 1985) plots of the intrusion rocks Figure 7. plots of the intrusion rocks in Feo/MgO- SiO2 (Miyashiro, 1974), B) SiO2 vs. K2O (Peccerillo and Taylor, 1976), c) A / NK vs. A / CNK (Maniar and Piccoli, 1989) 179 Tech J Engin & App Sci., 5 (1): 172-181, 2015 Figure 8. Plot of intrusion samples in diagrams of tectonic setting (Mullen, 1983; Pearce and cann, 1973). Geochemistry of ore Magnetite So far, there are many report that has been published about Fe- skarn (Einaudi, 1981; Sangster, 1969; Sokolov and Grigorev, 1977; Grigoryev and et al, 1990). This type of iron deposits has high reserve and it is economic value. We were take 60 sample from 10 deposit mass distinct exposures as systematically and were performed atomic absorption and XRF analysis. The results obtained display in Table 4 as 10 samples (1 sample for per deposit mass). Investigation about geochemistry ore samples shows similarity it to ore samples of the Canada (Ray and Webster, 1998), Finland (Nicolas and Miller, 2005) (Table 5). Also there are similarity of the amount of storage and accessory materials with ore deposits of Chile (Marschik and Leveille, 1998), Europe (Polard, 2000) and Brazil (Bartonand et al , 1998) that suggests high ore reserves of the Iron with very low amounts of copper and gold (Table 6). Table 4. Tthe average results of 60 samples of the XRF Shahrak. Wt% SiO2 TiO2 Fe2O3 Al2O3 TFeO MnO MgO CaO Na2O K2O P2O5 L.O.I Total BH1 10.96 0.12 70.1 4.62 40.82 0.04 11 1.58 0 0 0.1 1 99.52 BH2 11.12 0.5 74.4 2.8 50 0.12 2.7 3.5 1.57 0.16 0.12 2.67 99.66 BH3 8.81 0.09 71.45 2.71 51 0.04 7.2 4.36 1.29 1.87 0.09 1.55 99.46 BH4 10 0.1 79.21 0.09 53 0.05 8.11 0.98 0 0 0.1 1 99.64 BH5 4.46 0.7 89.57 1.31 60.1 0.07 1.5 0.48 0 0 0.1 1.23 99.42 BH6 4.31 0.5 89.64 0.17 60.5 0 2.49 0.28 0.27 0.57 0 0.76 98.99 BH7 3.45 0.1 91.78 0.93 65.4 0 0.98 0.32 0 0 0 2.12 99.68 BH8 4.78 0.12 90.44 0.13 55.67 0 0.79 1.6 0 0 0 1.46 99.32 BH9 1.98 0.07 94 0.21 67.3 0.01 1.67 0.36 0 0 0.13 0.94 99.37 BH10 2.31 0.08 93.52 0.17 66.44 0.02 1.19 0.12 0 0 0.11 1.91 99.43 Table 5. Shahrak.ICP-MS analysis of samples of iron ore and compared to other ores CO 15 11 n.a Ni 35 5 110 V 450-1100 n.a 500-1300 As n.d 29 n.a Ag 0.1 0.1 n.a Zn 45 30 40 Pb 13 15 n.d Cu 33-520 27 20-500 Au 2 n.d n.a %Fe 51-58 n.a 32-70 Ore Shahrak Canada Finland Table 6. store Amount Shahrak iron ore and compared with those of different parts of the world Area Shahrak Chilly Europe Brazil %Cu 7 0.8-1 0.4 1.5 Au g/t 0.25 0.02 0.26 0.82 million ton Storage 20 366 300 170 accessories minerals V, Ti, Mn, Cr As,Mo,b,Zn Mo Mo, U 180 Tech J Engin & App Sci., 5 (1): 172-181, 2015 CONCLUSION Miocene intrusion bodies with different combinations injected into the Oligocene carbonate formation and were formed skarn with Fe- mineralization. Iron skarn Mineralogy Paragenesis indicates the presence of two endo and exo skarn . exoskarn is including garnet skarn zones , pyroxene skarn, skarn phlogopite, talc and amphibole skarn and skarn skarn is plagioclase. The presence of garnet, pyroxene, phlogopite, talc, and plagioclase and amphibole skarn type indicates the presence of both calcium and magnesium is in Shahrak area. Skarns consists two stages progressive metamorphism in 650 º C and retrograde metamorphism at temperatures less than 450ºC. Intrusion bodies are consisting of granite, granodiorite, monzonite to monzodiorite and syenite. These rocks belong to K-rich calc-alkaline to shoshonitic series. These bodies are metaluminous to weakly peraluminous and belong to the continental arc basalts. The most important Magnetite mineralization was occurred during progressive and regressive metamorphism in exoskarn and endoskarn. That has Mineralogical paragenesis such as hematite, limonite and goethite. The presence of low amounts of pyrite and chalcopyrite indicated sulfur low fugacity of the hydrothermal solutions. Shahrak ore deposit is Iron deposits of the lack of gold and copper that has high economic value by reserves of 20 million tons of magnetite. Acknowledgments This paper is part of the Shahrak Fe- mineralization and Tectonic Setting Project, which has been supported by the University of payam-e-noor. The authors would like to thank the University of payam-e-noor for supporting the fieldwork and analyses .We thank Mr.Shaykhi for Their help in the fieldwork and preparation of the samples. Also we thank anonymous reviewers for critical comments in the first version of this manuscript. REFERENCES Barton MD, Johnson DA, Hanson RB. 1998. Evolution of possible roles of nonmagmatic brines in igneous- related hydrothermal systems, especially Fe (Cu-Au-REE) deposits. Geological Society of America 48: 237-250. De La Roche. H. Leterrier. J. Grand Claude. P. and Marchal. M, 1980. 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