Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
4.1
2.2
Journals
Minerals
Special Issues
Gold Deposits in Brazil
share announcement

Gold Deposits in Brazil

A special issue of Minerals (ISSN 2075-163X). This special issue belongs to the section "Mineral Deposits".

Deadline for manuscript submissions: closed (6 December 2020) | Viewed by 18931

Special Issue Editors

Prof. Dr. Lydia Maria Lobato

E-Mail Website
Guest Editor
Dept. Geologia, Centro de Pesquisa Prof. Manoel Teixeira da Costa, Instituto de Geociências, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP 31270-901, Belo Horizonte, MG, Brazil
Interests: metallogeny; economic geology; geochemistry
Dr. Rosaline Cristina Figueiredo e Silva

E-Mail Website
Guest Editor
Dept. Geologia, Centro de Pesquisa Prof. Manoel Teixeira da Costa, Instituto de Geociências, Universidade Federal de Minas Gerais, Av. Antônio Carlos 6627, CEP 31270-901, Belo Horizonte, MG, Brazil
Interests: metallogeny; economic geology; geochemistry
Prof. Dr. Steffen Hagemann

E-Mail Website
Guest Editor
Centre for Exploration Targeting, School of Earth and Environmental Sciences, University of Western Australia, Perth 6009, Australia
Interests: metallogeny; economic geology; geochemistry

Special Issue Information

Dear Colleagues,

Brazil has produced gold for many centuries. Its historical exploration, effort translates to a large number of gold deposits, from the Archean to the end of the Neoproterozoic, especially in orogenic-type systems. The majority of these are hosted in Archean and Paleoproterozoic granite–greenstone metavolcano-sedimentary sequences, in the states of Minas Gerais (Quadrilátero Ferrífero), Pará, Goiás, Mato Grosso, Maranhão, Amapá, Bahia and Goiás. The Neoproterozoic Morro do Ouro deposit in Minas Gerais is the largest metasedimentary belt to produce gold in an open pit mine. The Archean Cuiabá deposit (Quadrilátero Ferrífero) stands as the largest underground mine; it is hosted in BIF and shear-related quartz veins in mafic rocks. The Archean-age, IOCG-type Salobo deposit in the Carajás mineral province holds Brazil’s most significant gold (by product) resource.

This Special Issue will emphasize the recent advances of some selected Brazilian gold deposits and districts, focusing on their hydrothermal evolution and genesis. The chosen papers cover the most important producing regions in the country. One of the papers summarizes the distribution, production, and reserves in the form of tables and maps for all regions in Brazil.

This contribution will be co-edited by Dr. Rosaline C. Figueiredo e Silva, a lecturer at Universidade Federal de Minas Gerais, Brazil, and by Dr. Steffen G. Hagemann, professor at The University of Western Australia. It will also benefit from the experience of exploration geologist Marco Aurélio da Costa, a consultant and long-term contributer to the knowledge of gold in Brazil.

Prof. Dr. Lydia Maria Lobato
Dr. Rosaline Cristina Figeuiredo e Silva
Prof. Dr. Steffen Hagemann
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Minerals is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Gold deposits
  • Brazil
  • hydrothermal
  • mineral system

Published Papers (4 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

Jump to: Review

35 pages, 10252 KiB  
Article
Linking Gold Systems to the Crust-Mantle Evolution of Archean Crust in Central Brazil
by Jessica Bogossian, Anthony I. S. Kemp and Steffen G. Hagemann
Minerals 2021, 11(9), 944; https://doi.org/10.3390/min11090944 - 30 Aug 2021
Cited by 4 | Viewed by 3520
Abstract
The Goiás Archean Block (GAB) in central Brazil is an important gold district that hosts several world-class orogenic gold deposits. A better comprehension of the crustal, tectono-magmatic, and metallogenic settings of the GAB is essential to accurately define its geological evolution, evaluate Archean [...] Read more.
The Goiás Archean Block (GAB) in central Brazil is an important gold district that hosts several world-class orogenic gold deposits. A better comprehension of the crustal, tectono-magmatic, and metallogenic settings of the GAB is essential to accurately define its geological evolution, evaluate Archean crustal growth models, and target gold deposits. We present an overview of gold systems, regional whole-rock Sm-Nd analyses that have been used to constrain the geological evolution of the GAB, and augment this with new in situ zircon U-Pb and Hf-O isotope data. The orogenic gold deposits show variable host rocks, structural settings, hydrothermal alteration, and ore mineralogy, but they represent epigenetic deposits formed during the same regional hydrothermal event. The overprinting of metamorphic assemblages by ore mineralogy suggests the hydrothermal event is post-peak metamorphism. The metamorphic grade of the host rocks is predominantly greenschist, locally reaching amphibolite facies. Isotope-time trends support a Mesoarchean origin of the GAB, with ocean opening at 3000–2900 Ma, and reworking at 2800–2700 Ma. Crustal growth was dominated by subduction processes via in situ magmatic additions along lithospheric discontinuities and craton margins. This promoted a crustal architecture composed of young, juvenile intra-cratonic terranes and old, long-lived reworked crustal margins. This framework provided pathways for magmatism and fluids that drove the gold endowment of the GAB. Full article
(This article belongs to the Special Issue Gold Deposits in Brazil)
►▼ Show Figures

Figure 1

43 pages, 9332 KiB  
Article
Gold in Paleoproterozoic (2.1 to 1.77 Ga) Continental Magmatic Arcs at the Tapajós and Juruena Mineral Provinces (Amazonian Craton, Brazil): A New Frontier for the Exploration of Epithermal–Porphyry and Related Deposits
by Caetano Juliani, Rafael Rodrigues de Assis, Lena Virgínia Soares Monteiro, Carlos Marcello Dias Fernandes, José Eduardo Zimmermann da Silva Martins and Jhoseph Ricardo Costa e Costa
Minerals 2021, 11(7), 714; https://doi.org/10.3390/min11070714 - 1 Jul 2021
Cited by 11 | Viewed by 5512
Abstract
This review paper aims to integrate geological, tectonic and metallogenetic data, including new data, and propose a regional model for the gold (and base metal) mineralization in the south Amazonian Craton to support the mineral exploration concerning magmatic–hydrothermal deposits. The Proterozoic evolution of [...] Read more.
This review paper aims to integrate geological, tectonic and metallogenetic data, including new data, and propose a regional model for the gold (and base metal) mineralization in the south Amazonian Craton to support the mineral exploration concerning magmatic–hydrothermal deposits. The Proterozoic evolution of the Amazonian Craton comprises the accretion of terrains to the Archean Carajás Mineral Province. In the Tapajós and Juruena mineral provinces, located at the south part of the Amazonian craton, a long-lived ocean–continent subduction event produced ca. 2.0 to 1.77 Ga continental magmatic arcs. Extensive lava flows, volcaniclastic, sedimentary, and plutonic rocks were originated during at least four major orogenic magmatic events (ca. 2.1, 1.9, 1.88, and 1.80 Ga) and two post- to anorogenic events (ca. 1.87 and 1.77 Ga). Gold mineralization occurs in: (i) alluvial/colluvial occurrences, (ii) orogenic carbonate–sulfide-rich quartz veins in shear zones, (iii) stockworks, veins, and dissemination in granites, (iv) contact of basic dikes, (v) well-preserved high-, intermediate- and low-sulfidation epithermal mineralization, and (vi) porphyry-like and intrusion-related gold systems associated with late- to post-orogenic epizonal granites. The estimated historical gold production, mainly in secondary deposits, is over 27 Moz at the Tapajós and 6 Moz at the Juruena provinces. A total resource of over 5 Moz Au is currently defined in several small to large primary gold deposits. Andesite to rhyolite, volcaniclastic, and clastic sedimentary rocks (1.96–1.88 Ga) host epithermal (high-, intermediate-, and low-sulfidation) Au–(Ag–Pb–Zn) mineralization, whereas Au–Cu and Cu–Mo–Au mineralization is hosted in sub-volcanic tonalitic to granitic plutons. Advanced argillic alteration (alunite, pyrophyllite, enargite) associated with high-sulfidation mineralization occurs in ring volcanoes around nested volcanic calderas. This zone grades outward to propylitic or chlorite alteration, often covered by silica caps with vuggy silica. Lava flows and volcaniclastic rocks within faults or associated with volcanic edifices and rhyolitic domes host low- and intermediate-sulfidation mineralization. Low-sulfidation alteration zones typically have adularia and illite or sericite. Chalcopyrite, sphalerite, galena, pyrite, digenite, and manganiferous calcite are related to intermediate-sulfidation gold mineralization. Late- to post-orogenic evolved oxidized I-type granitoids host alkalic-type epithermal and porphyry-like gold mineralization. Porphyry-style hydrothermal alteration is analogous to those of modern systems, with inner sodic and potassic (potassic feldspar ± biotite or biotite) alterations grading to propylitic, muscovite-sericite, chlorite–sericite, and chlorite alterations. Potassic alteration zones are the locus of Cu–Mo mineralization, and gold-rich zones occur in muscovite/sericite–quartz–pyrite alteration. The Paleoproterozoic epithermal and porphyry-like mineralization in these large provinces defines a new frontier for the exploration of world-class gold deposits in the worldwide Proterozoic arc-related magmatic terrains. Full article
(This article belongs to the Special Issue Gold Deposits in Brazil)
►▼ Show Figures

Graphical abstract

38 pages, 12831 KiB  
Article
Structural Evolution of the Rio das Velhas Greenstone Belt, Quadrilátero Ferrífero, Brazil: Influence of Proterozoic Orogenies on Its Western Archean Gold Deposits
by Orivaldo Ferreira Baltazar and Lydia Maria Lobato
Minerals 2020, 10(11), 983; https://doi.org/10.3390/min10110983 - 4 Nov 2020
Cited by 17 | Viewed by 5959
Abstract
The Quadrilátero Ferrífero region is located in the extreme southeast of the Brasiliano São Francisco craton, Minas Gerais state, Brazil. It is composed of (i) Archean TTG granite-gneaissic terranes; (ii) the Archean Rio das Velhas greenstone belt; (iii) the Proterozoic metasedimentary and metavolcano-sedimentary [...] Read more.
The Quadrilátero Ferrífero region is located in the extreme southeast of the Brasiliano São Francisco craton, Minas Gerais state, Brazil. It is composed of (i) Archean TTG granite-gneaissic terranes; (ii) the Archean Rio das Velhas greenstone belt; (iii) the Proterozoic metasedimentary and metavolcano-sedimentary covers. The Rio das Velhas rocks were deposited in the synformal NW–SE-directed Nova Lima basin. The Archean deformation converted the Nova Lima basin into an ample synclinorium with an eastern inverted flank. Archean orogenic gold mineralization within the Rio das Velhas greenstone belt rocks is controlled by NNW–SSE-directed, Archean regional shear zones subparallel to the strata of the Nova Lima synclinorium borders. Transamazonian and Brasiliano orogenies are superposed onto the Archean structures that control gold mineralization. In the eastern domain, Brasiliano fold-and-fault belts prevail, whereas in the western domain Archean and Transamazonian structures abound. The present study focus mainly is the western domain where the Cuiabá, Morro Velho, Raposos, Lamego and Faria deposits are located. Gold orebodies plunge to the E–NE and are tectonically controlled by the Archean D1–D2 deformation. The D3 Transamazonian compression—Which had a SE–NW vector sub-parallel to the regional mineralized Archean foliation/bedding—Buckled these structures, resulting in commonly open, synformal and antiformal regional folds. These are well documented near the gold deposits, with NE–SW axial traces and fold axes plunging to E–NE. Such folds are normal to inverted, NW-verging, with an axial planar foliation dipping moderately to the SE. The Transamazonian compression has only been responsible for the reorientation of the mineralized Archean gold ores, due to coaxial refolding characterized by an opposite tectonic transport. It has therefore not caused any other significant changes. Thrust shear zones, sub-parallel to the strong Transamazonian foliation, have given rise to localized metric segmentation and to the dislocation of gold orebodies. Throughout the region, along the towns of Nova Lima to Sabará, structures pertaining to the Brasiliano Araçuaí orogeny are represented only by gentle folding and by a discrete, non-pervasive crenulation cleavage. Thrust-shear zones and small-scale normal faults have caused, at most, metric dislocations along N–S-oriented planes. Full article
(This article belongs to the Special Issue Gold Deposits in Brazil)
►▼ Show Figures

Figure 1

Review

Jump to: Research

27 pages, 15681 KiB  
Review
The Orogenic Crixás Gold Deposit, Goiás, Brazil: A Review and New Constraints on the Structural Control of Ore Bodies
by Stanislav Ulrich, Steffen Hageman, Juliana Charão Marques, Frederico Lana A. R. Figueiredo, João E. F. Ramires, José Carlos Frantz and Klaus Petersen
Minerals 2021, 11(10), 1050; https://doi.org/10.3390/min11101050 - 28 Sep 2021
Cited by 5 | Viewed by 2491
Abstract
A review of the current knowledge of lithostratigraphy, geochronology, mineralogy, alteration, fluid chemistry and structural data is provided in order to discuss the main controls on mineralization in the Crixás gold deposit and the existing structural framework and evolution. Gold mineralization at Crixás [...] Read more.
A review of the current knowledge of lithostratigraphy, geochronology, mineralogy, alteration, fluid chemistry and structural data is provided in order to discuss the main controls on mineralization in the Crixás gold deposit and the existing structural framework and evolution. Gold mineralization at Crixás represents orogenic upper mesothermal to lower hypothermal types developed within the overturned Paleoproterozoic (Rhyacian) stratigraphic sequence. The structural data indicates that upright folding of the stratigraphy and formation of a distinct S1 foliation characterizes D1 deformation. This controls the formation of laminated quartz veins, precipitation of Au-rich sulfides, and the development of NW trending orebodies. Localized F2 folding of D1 structures and strong L2 stretching lineations characterizes the D2 event. This localized F2 folding created oreshoots trending W-WNW within distinct orebodies. The D2 deformation is associated with the precipitation of native Au. The ‘bulk plunge’ of these orebodies is a combination of both plunges defined by D1 and D2 deformation events. A critical assessment of lithostratigraphic and structural data reveal two possible tectonic scenarios operating during the Paleoproterozoic. The first possible tectonic scenario considers sagduction and the development of a regional-scale synclinorium, followed by tilting and localized folding of D1 structures. The second scenario, which is similar to the current model, considers accretion producing a synclinorium, followed by thrusting. Based on the current knowledge, both models are considered to be permissible and a series of focused research studies are proposed to test both the current and the new tectonic models. Full article
(This article belongs to the Special Issue Gold Deposits in Brazil)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-4
Back to TopTop