Field trip report. Quadrilátero Ferrífero, Brazil July nd 2017

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1 Field trip report Quadrilátero Ferrífero, Brazil July nd 2017

2 Acknowledgment We would first like to thank SEG (Society of Economic Geologists) for the financial resource used for the trip. To UFPR (Universidade Federal do Paraná), which, even with financial problems provided us transportation. We thank the professors who collaborated with us for the trip, especially Professor Rosaline Silva and Professor Lydia Lobato (Universidade Federal de Minas Gerais) for the introductory lectures on regional geology and Fe and Au deposits and the UFMG SEG Student Chapter for the warm welcome and the organization of the lectures. We are grateful to AngloGold Ashanti, Companhia Siderúrgica Nacional (CSN) and Vale for allowing us to visit their mines and to their geologists who accompanied us: Rogério, André, Rafael, Frederico and Suellen (AngloGold Ashanti); Vitor (CSN); and Natércia (Vale). Finally, we thank our academic advisor Professor João Carlos Biondi for the knowledge shared and his partnership during the whole trip. Members of the UFPR SEG Student Chapter who participated in the fieldtrip, pictured at Vale s Fe mine. Biondi (advisor), Bruno, Laisa, Luiza, Andressa, Daiane, Alberto, Matheus e Ivan.

3 Introduction The technical visit to Quadrilátero Ferrífero (QF) began on July 17th and ended on July 22 nd. UFPR SEG visited open pit mines of three companies, as well as a lecture about the regional geology of QF at UFMG with SEG Student Chapter partners. The purpose of the trip was to visit one of the largest mineral provinces in the world and to understand the geological settings, as well as the metallogenesis. In addition to the geological and economic importance, QF is a historical region for the development of mining in Brazil. UFPR SEG also visited three mining companies: AngloGold Ashanti (Sabará, Minas Gerais), Companhia Siderúrgica Nacional (Congonhas, Minas Gerais) and Vale (Nova Lima, Minas Gerais). These mines are among the largest producers of Au or Fe in Brazil. Participants João Carlos Biondi Professor Academic advisor Alberto Caixeta Botelho Undergrad student Vice-president UFPR SEG SC Andressa de Araújo Silva Undergrad student Secretary UFPR SEG SC Bruno Henrique de Moura Merss Undergrad student Member UFPR SEG SC Daiane Munch Undergrad student Member UFPR SEG SC Ivan Rossi Undergrad student Member UFPR SEG SC Laisa Stingelin Colaço Undergrad student Member UFPR SEG SC Luiza Silva de Freitas Undergrad student President UFPR SEG SC Matheus Tonioti da Purificação Undergrad student Member UFPR SEG SC

Brazil route from Curitiba (A) to Belo Horizonte (B) Quadrilátero

4 Logistics and Location QF is 1000 km (620 miles) from Curitiba, from where we started our trip. Transportation was provided by UFPR. Brazil route from Curitiba (A) to Belo Horizonte (B) Quadrilátero Ferrífero map showing the mines visited (yellow) and cities of the region (blue)

5 Activities July 17 th, Start of the trip Curitiba (PR) to Jundiaí (SP) - Overnight in Jundiaí July 18 th, Morning: Jundiaí to Belo Horizonte (MG) - Afternoon: meeting and talks about QF with UFMG SEG Student Chapter - Overnight in Belo Horizonte July 19 th, Morning: visit at Lamego Mine AngloGold Ashanti - Afternoon: visit the drill core deposit of the Cuiabá Mine AngloGold Ashanti - Overnight in Conselheiro Lafaiete July 20 th, Visit at Casa de Pedra Mine Companhia Siderúrgica Nacional (CSN) - Visit and overnight in Ouro Preto July 21 st, Visit at Capão Xavier Mine / Mutuca - Vale - Afternoon: visit the Mines and Metal Museum - Gerdau - Overnight in Belo Horizonte July 22 nd, Return to Curitiba, overnight in Jundiaí (SP).

Lectures on the Geology of QF and associated deposits Two lectures on the geology and mineral deposits of QF were organized by UFMG SEG, and held on July 18 th at UFMG Geosciences Institute in Belo

6 Lectures on the Geology of QF and associated deposits Two lectures on the geology and mineral deposits of QF were organized by UFMG SEG, and held on July 18 th at UFMG Geosciences Institute in Belo Horizonte and included participation from 25 people. "Examples of Iron Deposits in Quadrilátero Ferrífero", was presented by Professor Rosaline Cristina Figueiredo e Silva. General aspects of the formations that compose the São Francisco Craton were reviewed, specifically the stratigraphy of the Minas Supergroup, where the iron deposits in the region are concentrated. These deposits are part of the Cauê Formation and they are Paleoproterozoic superior type BIF composed by itabirites and massive hematite. Hypogenic and supergenic processes are associated with high concentrations of iron. "Gold in Brazil: main deposits, production and prospects", presented by Professor Lydia Lobato, covered the main metallogenetic systems that generated the largest gold deposits in Brazil: orogenic, IOCG and hydrothermal magmatic. Emphasis was given to Au-orogenic type deposits in Rio das Velhas Greenstone Belt of São Francisco Craton, among them the Archean deposits of Lamego and Cuiabá, both hosted in BIFs. UFPR and UFMG SEG participants and professors Rosaline e Lydia.

Lamego and Cuiabá Mine AngloGold Ashanti The visit at Cabeça de Pedra pit from the Lamego Mine occurred on July 19 th and was accompanied by three geologists from AngloGold Ashanti (Rogério, André

7 Lamego and Cuiabá Mine AngloGold Ashanti The visit at Cabeça de Pedra pit from the Lamego Mine occurred on July 19 th and was accompanied by three geologists from AngloGold Ashanti (Rogério, André and Rafael). The mine is an open-pit type and the mineral deposit is classified as Au meso to epithermal orogenic type. The mineralization is hosted in the sedimentary and volcanic sequences of the Rio das Velhas greenstone belt, metamorphosed in greenschist facies and arranged in an antiform fold dipping to SE. Gold mineralization is related to formation of smoky quartz, which were fluid feeders that promote the sulphidation of the iron layers of BIFs, generating Christmas tree structures (Fig. 1). Gold occurs both in free form in quartz veins, as well as associated with pyrite and other sulfides. The evolution of the deposit is associated with the percolation of gold rich thiosulfate fluids from shear zones and destabilization of the latter in the iron layers of BIFs and in the contact with carbonaceous phyllite above. 1 The visit at Cuiabá Mine, also owned by AngloGold Ashanti, was not possible due to operational issues with the underground mine. In the meantime, it was possible to see the drill core deposit, where the mine geology was presented to us by the geologists Frederico and Suellen. The deposit is a stratabound type, hosted in BIFs and volcanoclastic sulfates. The arrangement of the mineralized layers occurs in the folded flank of a sheath fold plunging to the southeast. The high sulfur activity of the fluid promoted precipitation of pyrite and gold (proximal), and pyrrhotite (distal).

9 Casa de Pedra Mine Companhia Siderúrgica Nacional (CSN) The visit at Casa de Pedra Mine took place on July 20 th. It is the second largest ore exporter in Brazil, with resources of 6 billion tons of high-grade ore (> 64% Fe) with production of 30 million tons per year. The mineral deposit explored in Casa de Pedra Mine is located between the Sinclinal Moeda and Sinclinal Dom Bosco, composing the Cauê, Paleoproterozoic Formation of the Minas Supergroup. The ore, composed of massive hematite and dolomites, is oriented according to NW- SE lineaments, plunging 110/45. The hypothesis of formation of this deposit is through hypogenic processes of carbonation of the silicate BIFs, conducted through NW faults, and superimposed supergenesis with the leaching of part of the carbonate and concentrating high grade ore. In the main body, the primary feeder of the plant, the ore is friable hematite, with high Fe content (68-69%). This ore forms due to the weathering of carbonated BIFs, concentrating hematite in the residual form, as observed in the slopes of the mine (Fig. 2). BIFs also occur with hydrothermal specularite, but these do not constitute large accumulations of Fe. 2

Capão Xavier Mine - Vale Located in Nova Lima, near Belo Horizonte, Capão Xavier Mine produces about 15 million tons of Fe ore annually, with 62% content and 52% cutoff.

The mineralized body occurs between the dolomites of the Gandarela Formation and the phyllites of the Batatal Formation, Paleoproterozoic of the Minas Supergroup, São Francisco Craton.

11 Capão Xavier Mine - Vale Located in Nova Lima, near Belo Horizonte, Capão Xavier Mine produces about 15 million tons of Fe ore annually, with 62% content and 52% cutoff. The ore is composed of compact goethite, hematite, friable hematite, specularite, compact dolomitic itabirite and siliceous itabirite (Fig. 3). The mineralized body occurs between the dolomites of the Gandarela Formation and the phyllites of the Batatal Formation, Paleoproterozoic of the Minas Supergroup, São Francisco Craton. The itabirites host formations of Fe mineralization, with intermediate to low levels of MnO and MgO. The metamorphism was at a very low degree, with weak deformation, evidenced by the presence of greenalite (diagenetic) in the BIFs silicate facies. The iron formations are interpreted as a superior type. The higher content of itabirite ore occurs in hinge and axial planes of folds. Supergenic processes were fundamental for the generation of the ore, with the formation of weathering profile as shown in the figure. The gangue, bauxite and geothite are the product of chemical leaching, friable hematite as residual concentrate and massive hematite as supergenic concentrate. 3

13 Mines and Metal Museum - Gerdau

14 UFPR SEG Student Chapter Committee 2017 João Carlos Biondi Academic Advisor Francisco de Azevedo, Jr. Industry Advisor Evandro Klein Industry Advisor Luiza Silva de Freitas President Alberto Caixeta Botelho Vice President Andressa de Araujo Silva Secretary Guilherme Fedalto - Treasurer

SOCIETY OF ECONOMIC GEOLOGISTS, INC Shaffer Parkway Littleton, CO USA Tel: Fax:

SOCIETY OF ECONOMIC GEOLOGISTS, INC. 7811 Shaffer Parkway Littleton, CO 80127-3732 USA Tel: +1.720.981.7882 Fax: +1.720.981.7874 E-mail: studentprograms@segweb.org Student Chapter Annual Report Form This