Article
Geosciences, Multidisciplinary
Gabriel Oliveira Sepulveda, Tiago Amancio Novo, Jorge Roncato
Summary: This passage discusses the Quadrilatero Ferrifero (QF) in Brazil, detailing sedimentology study and X-ray diffraction analyses of the Corrego do Sitio unit. The sedimentary structures of CdS are interpreted as turbidity currents deposits, influenced by the Rio das Velhas II magmatic event. Geological dating data suggests a potential convergent to a collisional marginal tectonic setting during deposition.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2021)
Article
Multidisciplinary Sciences
Mariana Lemos, Teresa Valente, Paula Marinho Reis, Rita Fonseca, Joao Paulo Pantaleao, Fernanda Guabiroba, Jose Gregorio Filho, Marcus Magalhaes, Bruno Afonseca, Antonio Roberto Silva, Itamar Delbem
Summary: This study evaluated the potential reuse of gold ore wastes in Nova Lima, Brazil through geochemical, mineralogical, 3D modeling, and metallurgical analyses. The characterization identified sulfides and oxides in the wastes, as well as high grades of gold and other metals. 3D modeling revealed the presence of gold enrichment zones and attractive tailing deposits. Metallurgical tests showed a 70% gold recovery rate and suggested other potential reuses of the wastes. This study highlights the importance of integrative characterization in the circular economy and the value of tailings in the mineral sector.
SCIENTIFIC REPORTS
(2023)
Article
Geosciences, Multidisciplinary
Raphael do Carmo Fernandes, Jorge Roncato, Rodrigo Sergio de Paula
Summary: The purpose of this study is to characterize the structural features of the Cuiabá gold deposit in order to propose a new model of tectonic evolution. The study found that the deposit is characterized by two tectonic events and three deformation phases, with gold mineralization associated with D1 and D2 axial-plane foliation. There is no field evidence supporting the existence of sheath folds in the deposit. Based on deposit morphology and fold interference patterns, SW and N directions are inferred as prospective exploration targets, with potential structural connection to other gold deposits such as Lamego and Descoberto.
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2023)
Article
Environmental Sciences
Amanda Ribeiro de Oliveira, Fernando Antonio Leal Pacheco, Luis Filipe Sanches Fernandes, Adriana Monteiro da Costa
Summary: Despite promises to increase control and fight against deforestation, the new Brazilian Forest Code allowed more flexible rules for protecting native vegetation on private rural properties. However, after a decade of implementation, oversight and monitoring of these properties were not up to expectations. This study found that a significant number of private rural properties had experienced potentially illegal deforestation, with a concentration of deforested areas in small sectors within the properties.
LAND DEGRADATION & DEVELOPMENT
(2023)
Article
Geochemistry & Geophysics
Felipe Emerson Andre Alves, Atlas Vasconcelos Correa Neto, Mariana Brando Soares, Reiner Neumann, Gabriel Machado da Silva, Gabriela Pereira Silva, Ana Clara Varca, Piero Azevedo Berquo de Sampaio, Vitor Diniz Silveira
Summary: This study investigates the mineralogical and geochemical characteristics of the Zona Basal mineral occurrence in Brazil, revealing a two-stage mineralizing system. It emphasizes the importance of considering retrograde or cooling reactions and mineral re-equilibrium in addressing complex ore formation.
CONTRIBUTIONS TO MINERALOGY AND PETROLOGY
(2022)
Article
Geochemistry & Geophysics
Brandon Choquette, Daniel J. Kontak
Summary: The Windfall gold deposit in the Urban-Barry greenstone belt of Quebec, Canada, is an emerging and significant gold deposit with a resource of 7.4 Moz of Au. The gold mineralization is associated with 2717 Ma bimodal volcanic rocks and is localized to faults and fractures proximal to the contacts of the early quartz-feldspar porphyry dikes. The mineralization occurs in quartz veins, stockworks, and alteration zones.
Article
Geology
Chenglu Li, Changzhou Deng, Shengrong Li, Maowen Yuan, Masroor Alam, Baoshan Liu, Zhonghai Zhao, Wenlong Li, Yuanjiang Yang
Summary: The newly discovered Mengdehe orogenic gold deposit in the Xing?an-Mongolia Orogenic Belt is the first mylonitic rocks-hosted and brittle-ductile shear zone-dominated gold deposit in the eastern region. The gold deposit formation is dated to the Late Triassic and linked to a strike-slip event, with ore-forming materials derived from crustal sources with orogenic affinity. The mineralization is believed to be in response to the tectonic transformation from compression to extension related to the final closure of the Paleo-Asian Ocean.
ORE GEOLOGY REVIEWS
(2021)
Article
Environmental Sciences
E. C. G. Hastie, M. Schindler, D. J. Kontak, B. Lafrance
Summary: The study on gold nanoparticles and related textures in gold deposits provides insights into the mechanism of high-grade gold ore formation through secondary dissolution-reprecipitation processes, contributing to the understanding of orogenic deposits.
COMMUNICATIONS EARTH & ENVIRONMENT
(2021)
Article
Geosciences, Multidisciplinary
Shun-Da Li, Chuan Chen, Ling-Ling Gao, Fang Xia, Xue-Bing Zhang, Ke-Yong Wang
Summary: The Jinba gold deposit, located in the Maerkakuli Shear Zone of the south Altay Orogenic Belt in NW China, is classified as altered rock-and quartz vein-type mineralization. The deposit is undergoing investigation on three paragenetic stages of mineralization.
FRONTIERS IN EARTH SCIENCE
(2021)
Review
Geochemistry & Geophysics
Stanislav Ulrich, Steffen Hageman, Juliana Charao Marques, Frederico Lana A. R. Figueiredo, Joao E. F. Ramires, Jose Carlos Frantz, Klaus Petersen
Summary: The study discusses the main controls on mineralization in the Crixas gold deposit, analyzing lithostratigraphy, geochronology, mineralogy, alteration, fluid chemistry, and structural data. It reveals that gold mineralization at Crixas represents orogenic upper mesothermal to lower hypothermal types and is developed within an overturned Paleoproterozoic stratigraphic sequence.
Article
Geochemistry & Geophysics
Elliot A. Wehrle, Jean-Francois Montreuil, Iain M. Samson, Daniel J. Kontak, Mingqian Wu
Summary: The study reveals that the Wawa gold corridor in Canada is characterized by Au-bearing shear zones that developed during deformation events. Coupled dissolution-reprecipitation reactions have generated gold from pre-existing sulfides. The primary Au-mineralizing event in the Wawa gold corridor was the D1 arsenopyrite event.
Article
Geochemistry & Geophysics
Pranjit Hazarika, Dewashish Upadhyay, Biswajit Mishra, Pritom Borah, Kumar Abhinay
Summary: The source of mineralizing fluid in Archean greenstone-hosted orogenic gold deposits is widely debated, with geochemical and isotope data pointing to a complex formation process involving multiple fluid sources, leading to large variations in B-isotope composition of tourmaline. Modeling of boron release and associated fractionation during metamorphic dehydration of greenstone rocks suggest distinct delta B-11 distributions from different fluid sources, highlighting the importance of understanding metamorphic processes in evaluating fluid sources for orogenic gold deposits.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2021)
Article
Geology
M. Z. Abzalov, A. Smith, M. J. Gole, T. Riggs
Summary: This study analyzes the geological and geochemical data of the Perseverance komatiite complex, revealing the heterogeneity characteristics of the komatiite channel and the geochemical indicators of the mineralized parts. The research also highlights the potential use of Ni/Cr and Ni/Ti ratios as geochemical pathfinders for magmatic sulphide deposits within the komatiite main lava pathway.
ORE GEOLOGY REVIEWS
(2022)
Article
Geology
Jinlei Sun, Ye Qian, Yujin Li, Peng Zhang, Jianfeng Qiao, Yanjie Shen, Fengyue Sun
Summary: The Naxiguole Banded Iron Formation (BIF) in the Eastern Kunlun Orogenic Belt, Northwest China, has been studied for its age and origin. It was formed in a sedimentary basin within an active continental island arc, with contributions from terrestrial clastic material and seawater. The findings suggest its similarities with Superior-type BIFs worldwide.
INTERNATIONAL GEOLOGY REVIEW
(2023)
Article
Geology
Wenbo Li, Fanghua Zhang, Chuansheng Hu, Lejun Zhang, Xueyuan Qiao
Summary: The Bieluwutu Cu-Pb-Zn deposit in North China is a Kuroko-type VHMS deposit formed in the Early Silurian, containing massive Pb-Zn, brecciated Cu-Zn, and disseminated Cu ores. Research shows differences in element enrichment among different types of ores, as well as a trend of decreasing temperature and increasing f(O-2) from disseminated to brecciated and massive ores.
ORE GEOLOGY REVIEWS
(2021)
Article
Geochemistry & Geophysics
Monica Mendes, Lydia M. Lobato, Marcus Kunzmann, Galen P. Halverson, Carlos A. Rosiere
MINERALIUM DEPOSITA
(2017)
Article
Geology
Sylvio D. Gomes, Sarah Berger, Rosaline C. Figueiredo e Silva, Steffen G. Hagemann, Carlos A. Rosiere, David A. Banks, Lydia M. Lobato, Ana-Sophie Hensler
ORE GEOLOGY REVIEWS
(2018)
Article
Geochemistry & Geophysics
Wendell Fabricio-Silva, Carlos Alberto Rosiere, Bernhard Buhn
MINERALIUM DEPOSITA
(2019)
Article
Geochemistry & Geophysics
C. A. Spier, A. Levett, C. A. Rosiere
MINERALIUM DEPOSITA
(2019)
Article
Geosciences, Multidisciplinary
Yusuke Kuribara, Toshiaki Tsunogae, M. Santosh, Yusuke Takamura, Antonio Gilberto Costa, Carlos A. Rosiere
PRECAMBRIAN RESEARCH
(2019)
Article
Geosciences, Multidisciplinary
Carlos A. Rosiere, Andrey Bekker, Vassily K. Rolim, Joao Orestes S. Santos
Article
Geosciences, Multidisciplinary
Flavia Cristina Silveira Braga, Carlos Alberto Rosiere, Joao Orestes Schneider Santos, Steffen G. Hagemann, Neal J. McNaughton, Pedro Valle Salles
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2019)
Letter
Geosciences, Multidisciplinary
Yusuke Kuribara, Toshiaki Tsunogae, M. Santosh, Yusuke Takamura, Antonio Gilberto Costa, Carlos A. Rosiere
PRECAMBRIAN RESEARCH
(2021)
Article
Geochemistry & Geophysics
Flavia Cristina Silveira Braga, Joao Orestes Schneider Santos, Carlos Alberto Rosiere, Vassily K. Rolim, Malcolm P. Roberts, Noreen J. Evans, Steffen G. Hagemann
Article
Geosciences, Multidisciplinary
Sylvio D. Gomes, Rosaline C. Figueiredo e Silva, Anthony I. S. Kemp, Joao Orestes S. Santos, Steffen G. Hagemann, Lydia M. Lobato, Carlos A. Rosiere, Tiago A. Novo
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
(2020)
Article
Geosciences, Multidisciplinary
Landry Soh Tamehe, Chongtao Wei, Sylvestre Ganno, Carlos Alberto Rosiere, Jean Paul Nzenti, Chesther Gatse Ebotehouna, Guanwen Lu
Summary: The discovery of the Gouap banded iron formations in southwestern Cameroon provides unique insights into the geology of the region. Detailed geochemical, isotopic, and geochronological studies reveal the presence of amphibole BIFs and amphibole-pyrite BIFs formed during metamorphism and hydrothermal events, as well as enrichments in trace elements indicating detrital and hydrothermal influences. The isotopic data suggests deposition from low-temperature hydrothermal fluids with detrital input, with U-Pb zircon dating indicating deposition around 2422 Ma and regional metamorphism at 2089 Ma during orogeny.
GEOSCIENCE FRONTIERS
(2021)
Article
Geochemistry & Geophysics
Wendell Fabricio-Silva, Hartwig E. Frimmel, Maria Emilia Shutesky, Carlos A. Rosiere, Armando J. Massucatto
Summary: Against the backdrop of the ongoing debate on the genetic relationship between orogenic gold and granitic magmatism, a study of the gold-mineralizing system at the Satinoco deposit in Brazil revealed a complex polyphase history with at least three gold-bearing stages. The study indicated that gold mineralization took place over a wide range of temperatures, a finding that may not only apply to the Satinoco deposit but possibly to other orogenic-type gold deposits elsewhere as well.
Article
Geology
Flavia Cristina Silveira Braga, Carlos Alberto Rosiere, Joao Orestes Schneider Santos, Steffen G. Hagemann, Lenoid Danyushevsky, Pedro Valle Salles
Summary: The HBD and CTE are two high-grade iron ore deposits located in the Guanhaes Tectonic Block, hosted by metamorphic banded iron formations from the Orosirian to early Statherian period. The Fe-mineralization developed in three stages, with magnetite bodies forming during late-collisional stages and hematite crystallization due to late-to post-tectonic oxidation. The orebodies exhibit varying trace element contents and compositions, with different mineralization stages affecting the enrichment of the iron formations.
ORE GEOLOGY REVIEWS
(2021)
Article
Geology
C. A. Rosiere, J. O. S. Santos, F. Silveira Braga, A. Hensler, V. K. Rolim, A. Bekker
Summary: Large-scale iron mineralization systems were recurrently developed in the Sao Francisco craton during two orogenies, the Trans-Amazonian orogeny around 2.1-2.0 billion years ago and the Brasiliano orogeny during the Ediacaran to Cambrian period. Hydrothermal fluids played a significant role in the formation of iron deposits, with far-field hydrothermal alteration affecting a wide range of rock sequences in the cratonic core. The circulation of hydrothermal fluids during the Brasiliano orogeny caused desilicification, iron mobilization, and widespread alteration of rocks, with U-Pb dates pointing to multiple hydrothermal events during the Cambrian period.
JOURNAL OF GEOLOGY
(2021)
Article
Geochemistry & Geophysics
Ana-Sophie Hensler, Carlos A. Rosiere, Steffen G. Hagemann