Itabira Complex |
|
Minas Gerais, Brazil |
Main commodities:
Fe
|
|
|
|
|
|
Super Porphyry Cu and Au
|
IOCG Deposits - 70 papers
|
All papers now Open Access.
Available as Full Text for direct download or on request. |
|
|
The Itabira Complex, which includes the Conceicão, Córrego do Meio, Onca, Dois Córregos and Cauê mines, is located some 80 km to the ENE of Belo Horizonte in Minas Gerais, within an outlier of the Rio das Velhas and Minas Supergroups that are infolded into the surrounded Archaean gneissic complex which separates them from the main Quadrilátero Ferrífero (#location: 19° 38' 20"S, 43° 15' 21"W).
The operating mines of the complex exploit ore developed in the Cauê Itabirite at the base of the Itabira Formation of the Minas Supergroup. This unit is exposed over a continuous strike length of 11 km in a series of synformal and antiformal structures that collectively define a larger synclinorium.
For detail of the regional setting, geology and stratigraphy of the host sequence and district see the Quadrilatero Ferrifero Iron Province
The iron ores of the Itabira district occur both as hard high grade, 67% Fe hematite and as friable lower grade, 45-50% Fe itabirites that must be upgraded. In addition, the orebodies are mantled by canga, (detrital and lateritic material). The hematite ores are interpreted to be due to hypogene enrichment of the itabirites, while the friable ores are the result of supergene leaching of silica and iron enrichment. The geological resource is stated at 1.3 Gt of hematite ore and 2.8 Gt of friable ores.
The Itabira district was the original home of CVRD activities and currently involves a number of their operations, principally Cauê and Conceicão. Production from these mines totalled 39.9 Mt in the year 2000. Part of this output is sold to local steel mills while the bulk is railed 600 km to the company export port near Vitória on the Atlantic coast in the state of Espírito Santo where CVRD also has pellet plants. Cauê has been in production since 1942, while Conceicão commenced operation in 1957. Both are projected to be exhausted in the year 2014. Proven + probable reserves at Cauê in 2000 were 25 Mt @ 51.3% Fe, while at Conceicão there were 338 Mt @ 56.7% Fe, with a further 424 Mt at Dios Córregos grading 59.5% Fe in a number of deposits.
The Itabira district is reported to contain a total of 897 million tonnes of iron ore reserves as of the end of 2002, comprising 401 Mt of hematite and 496 Mt of itabirite. In addition there are 679 Mt of resources made up of 247 Mt of hematite and 432 Mt of itabirites, plus a further 1408 Mts of potential ore.
These lower grade ores have a high percentage of friable itabirite compared to hematite ore and require concentration to achieve shipping grades of 64% Fe. This is done by standard crushing, classification and concentration steps to produce sinter feed, lump ore and pellet feed.
The most recent source geological information used to prepare this decription was dated: 2002.
This description is a summary from published sources, the chief of which are listed below. © Copyright Porter GeoConsultancy Pty Ltd. Unauthorised copying, reproduction, storage or dissemination prohibited.
Itabira Complex
|
|
Barbour A P, 1973 - Distribution of phosphorous in the iron ore deposits of Itabira, Minas Gerais, Brazil.: in Econ. Geol. v32 pp 52-64
|
Cabral A R and Correa Neto A V, 2006 - Mercury-bearing manganiferous veinlets in compact haematite ore: the preliminary data from Fabrica deposit, Quadrilatero Ferrifero, Minas Gerais, Brazil: in Trans. IMM (incorp. AusIMM Proc.), Section B, Appl. Earth Sc. v115 pp 1-7
|
Cabral A R, Lehmann B, Galbiatti H F and Rocha Filho O G, 2006 - Evidence for metre-scale variations in hematite composition within the Palaeoproterozoic Itabira Iron Formation, Minas Gerais, Brazil: in Mineralogical Magazine v70 pp 591-602
|
Galbiatti H F, Fonseca M A, Pereira M C and Polonia J C, 2007 - Structural control of Au-Pd mineralization (Jacutinga): An example from the Caue Mine, Quadrilatero Ferrifero, Brazil: in Ore Geology Reviews v32 pp 614-628
|
Luders V, RomerR L, Cabral A R, Schmidt C, Banks D A and Schneider J 2005 - Genesis of itabirite-hosted Au-Pd-Pt-bearing hematite-(quartz) veins, Quadrilatero Ferrifero, Minas Gerais, Brazil: constraints from fluid inclusion infrared microthermometry, bulk crush-leach analysis and U-Pb systematics: in Mineralium Deposita v40 pp 298-306
|
Olivo G R, Gauthier M, Bardoux Sa E L, Fonseca J T F, Carbonari F 1995 - Palladium-bearing gold deposit hosted by Lake Superior-type iron formation at the Caue Iron Mine, Itabira District, Southern Sao Francisco Craton, Brazil: Geologic and structural controls: in Econ. Geol. v90 pp 118-134
|
Olivo G R, Gauthier M, Williams-Jones A E, Levesque M 2001 - The Au-Pd Mineralization at the Conceicao Mine, Itabira District, Southern Sao Francisco Craton, Brazil: An Example of a Jacutinga-Type Deposit: in Econ. Geol. v96 pp 61-74
|
Rosiere, C.A. and Rios, F.J., 2004 - The Origin of Hematite in High-Grade Iron Ores Based on Infrared Microscopy and Fluid Inclusion Studies: The Example of the Conceicao Mine, Quadrilatero Ferrifero, Brazil: in Econ. Geol. v.99, pp. 611-624.
|
Verissimo, Schrank A, Pires FRM, Hasui Y, Zanardo A, Parente CV 2002 - Geochemical Study of the Itabirite Iron Ores of the Alegria Mine - Quadrilatero Ferrifero, Minas Gerais, Brazil: in Proceedings, Iron Ore 2002 Conference, 9-11 September 2002, Perth, Western Australia, The AusIMM, Melbourne, pp 95-105
|
Porter GeoConsultancy Pty Ltd (PorterGeo) provides access to this database at no charge. It is largely based on scientific papers and reports in the public domain, and was current when the sources consulted were published. While PorterGeo endeavour to ensure the information was accurate at the time of compilation and subsequent updating, PorterGeo, its employees and servants: i). do not warrant, or make any representation regarding the use, or results of the use of the information contained herein as to its correctness, accuracy, currency, or otherwise; and ii). expressly disclaim all liability or responsibility to any person using the information or conclusions contained herein.
|
Top | Search Again | PGC Home | Terms & Conditions
|
|