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Amin Beiranvand Pour - One of the best experts on this subject based on the ideXlab platform.
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identification of Hydrothermal Alteration minerals associated with geothermal system using aster and hyperion satellite data a case study from yankari park ne nigeria
Geocarto International, 2019Co-Authors: Aliyu Jaafar Abubakar, Mazlan Hashim, Amin Beiranvand PourAbstract:Concealed and fossilized geothermal systems are not characterized by obvious surface manifestations like hotsprings and fumaroles, therefore, could not be easily identifiable using conventional techniques. In this investigation, the applicability of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Hyperion data-sets were evaluated in discriminating Hydrothermal Alteration minerals associated with geothermal systems as a proxy in identifying subtle Geothermal systems at Yankari Park, Nigeria. Feature-oriented principal component selection, spectral angle mapper, linear spectral unmixing were applied to ASTER data based on spectral characteristics of Hydrothermal Alteration key minerals for a systematic selective extraction of the information of interest. Analytical imaging and geophysics-developed processing methods were applied to Hyperion data for mapping iron oxide/hydroxide minerals and clay mineral assemblages in Hydrothermal Alteration zones. The results indicate that ASTER and Hyperion could be complemented for reconnaissance stage of targeting subtle Alteration mineral assemblages associated with geothermal systems.
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comparison of different algorithms to map Hydrothermal Alteration zones using aster remote sensing data for polymetallic vein type ore exploration toroud chahshirin magmatic belt tcmb north iran
Remote Sensing, 2019Co-Authors: Lida Noori, Amin Beiranvand Pour, Ghasem Askari, Nader Taghipour, Biswajeet Pradhan, Changwook Lee, Mehdi HonarmandAbstract:Polymetallic vein-type ores are important sources of precious metal and a principal type of orebody for various base-metals. In this research, Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) remote sensing data were used for mapping Hydrothermal Alteration zones associated with epithermal polymetallic vein-type mineralization in the Toroud–Chahshirin Magmatic Belt (TCMB), North of Iran. The TCMB is the largest known goldfield and base metals province in the central-north of Iran. Propylitic, phyllic, argillic, and advanced argillic Alteration and silicification zones are typically associated with Au-Cu, Ag, and/or Pb-Zn mineralization in the TCMB. Specialized image processing techniques, namely Selective Principal Component Analysis (SPCA), Band Ratio Matrix Transformation (BRMT), Spectral Angle Mapper (SAM) and Mixture Tuned Matched Filtering (MTMF) were implemented and compared to map Hydrothermal Alteration minerals at the pixel and sub-pixel levels. Subtle differences between altered and non-altered rocks and Hydrothermal Alteration mineral assemblages were detected and mapped in the study area. The SPCA and BRMT spectral transformation algorithms discriminated the propylitic, phyllic, argillic and advanced argillic Alteration and silicification zones as well as lithological units. The SAM and MTMF spectral mapping algorithms detected spectrally dominated mineral groups such as muscovite/montmorillonite/illite, hematite/jarosite, and chlorite/epidote/calcite mineral assemblages, systematically. Comprehensive fieldwork and laboratory analysis, including X-ray diffraction (XRD), petrographic study, and spectroscopy were conducted in the study area for verifying the remote sensing outputs. Results indicate several high potential zones of epithermal polymetallic vein-type mineralization in the northeastern and southwestern parts of the study area, which can be considered for future systematic exploration programs. The approach used in this research has great implications for the exploration of epithermal polymetallic vein-type mineralization in other base metals provinces in Iran and semi-arid regions around the world.
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detection of Hydrothermal Alteration zones in a tropical region using satellite remote sensing data bau goldfield sarawak malaysia
Ore Geology Reviews, 2013Co-Authors: Amin Beiranvand Pour, Mazlan Hashim, John Van GenderenAbstract:Abstract Remote sensing for geology in tropical environments is very challenging, because of the dense vegetation cover and the problem of persistent cloud cover. In this research paper, we have investigated and demonstrated the detection of Hydrothermal Alteration zones and structural elements associated with intrusion-related gold mineralization using various types of remote sensing data in the Bau gold mining district in the State of Sarawak, East Malaysia, on the island of Borneo. The climate of Bau is tropical with persistent cloud cover and very dense vegetation ground. Geological analyses coupled with remote sensing data were used to detect Hydrothermally altered rocks and structural elements associated with gold mineralization in the Bau area. Landsat Enhanced Thematic Mapper+ (ETM+), Hyperion and Phased Array type L-band Synthetic Aperture Radar (PALSAR) data were used to carry out lithological–structural mapping of the mineralized zones in the study area and surrounding terrain. Hydrothermal Alteration zones were detected along the SSW to NNE structural trend of the Tai Parit fault that corresponds with the occurrence of other gold mineralization in the Bau Limestone. The results show that the known gold prospects and potential areas of mineralization are recognizable by the methods used, despite limited bedrock exposure. The approach used in this study is broadly applicable to the detection of gold mineralization using ETM+, Hyperion and PALSAR data in tropical/sub-tropical regions.
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identification of Hydrothermal Alteration minerals for exploring of porphyry copper deposit using aster data se iran
Journal of Asian Earth Sciences, 2011Co-Authors: Amin Beiranvand Pour, Mazlan HashimAbstract:The NW–SE trending Central Iranian Volcanic Belt hosts many well-known porphyry copper deposits in Iran. It becomes an interesting area for remote sensing investigations to explore the new prospects of porphyry copper and vein type epithermal gold mineralization. Two copper mining districts in southeastern segment of the volcanic belt, including Meiduk and Sarcheshmeh have been selected in the present study. The performance of Principal Component Analysis, band ratio and Minimum Noise Fraction transformation has been evaluated for the visible and near infrared (VNIR) and, shortwave infrared (SWIR) subsystems of ASTER data. The image processing techniques indicated the distribution of iron oxides and vegetation in the VNIR subsystem. Hydrothermal Alteration mineral zones associated with porphyry copper mineralization identified and discriminated based on distinctive shortwave infrared (SWIR) properties of the ASTER data in a regional scale. These techniques identified new prospects of porphyry copper mineralization in the study areas. The spatial distribution of Hydrothermal Alteration zones has been verified by in situ inspection, X-ray diffraction (XRD) analysis, and spectral reflectance measurements. Results indicated that the integration of the image processing techniques has a great ability to obtain significant and comprehensive information for the reconnaissance stages of porphyry copper exploration in a regional scale. The results of this research can assist exploration geologists to find new prospects of porphyry copper and gold deposits in the other virgin regions before costly detailed ground investigations. Consequently, the introduced image processing techniques can create an optimum idea about possible location of the new prospects.
Michael Heap - One of the best experts on this subject based on the ideXlab platform.
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Quantifying the role of Hydrothermal Alteration in creating geothermal and epithermal mineral resources: The Ohakuri ignimbrite (Taupō Volcanic Zone, New Zealand)
Journal of Volcanology and Geothermal Research, 2019Co-Authors: Michael Heap, H. Albert Gilg, Darren Gravley, Ben Kennedy, Elisabeth Bertolett, Shaun L L BarkerAbstract:Hydrothermal fluids can alter the chemical and physical properties of the materials through which they pass and can therefore modify the efficiency of fluid circulation. The role of Hydrothermal Alteration in the development of geothermal and epithermal mineral resources, systems that require the efficient Hydrothermal circulation provided by fracture networks, is investigated here from a petrophysical standpoint using samples collected from a well exposed and variably altered palaeo-Hydrothermal system hosted in the Ohakuri ignimbrite deposit in the Taupō Volcanic Zone (New Zealand). Our new laboratory data show that, although quartz and adularia precipitation reduces matrix porosity and permeability, it increases the uniaxial compressive strength, Young’s modulus, and propensity for brittle behaviour. The fractures formed in highly altered rocks containing quartz and adularia are also more planar than those formed in their less altered counterparts. All of these factors combine to enhance the likelihood that a silicified rock-mass will host permeability-enhancing fractures. Indeed, the highly altered silicified rocks of the Ohakuri ignimbrite deposit are much more fractured than less altered outcrops. By contrast, smectite Alteration at the margins of the Hydrothermal system does not significantly increase strength or Young’s modulus, or significantly decrease permeability, and creates a relatively unfractured rock-mass. Using our new laboratory data, we provide permeability modelling that shows that the equivalent permeability of a silicified rock-mass will be higher than that of a less altered rock-mass or a rock-mass characterised by smectite Alteration, the latter of which provides a low-permeability cap required for an economically viable Hydrothermal resource. Our new data show, using a petrophysical approach, how Hydrothermal Alteration can produce rock-masses that are both suitable for geothermal energy exploitation (high-permeability reservoir and low-permeability cap) and more likely to host high-grade epithermal mineral veins, such as gold and silver (localised fluid flow).
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Hydrothermal Alteration of andesitic lava domes can lead to explosive volcanic behaviour
Nature Communications, 2019Co-Authors: Michael Heap, Valentin Troll, Alexandra Kushnir, H. Albert Gilg, Amy Collinson, Frances Deegan, Herlan Darmawan, Nadhirah Seraphine, Juergen Neuberg, Thomas WalterAbstract:Dome-forming volcanoes are among the most hazardous volcanoes on Earth. Magmatic outgassing can be hindered if the permeability of a lava dome is reduced, promoting pore pressure augmentation and explosive behaviour. Laboratory data show that acid-sulphate Alteration, common to volcanoes worldwide, can reduce the permeability on the sample lengthscale by up to four orders of magnitude and is the result of pore- and microfracture-filling mineral precipitation. Calculations using these data demonstrate that intense Alteration can reduce the equivalent permeability of a dome by two orders of magnitude, which we show using numerical modelling to be sufficient to increase pore pressure. The fragmentation criterion shows that the predicted pore pressure increase is capable of fragmenting the majority of dome-forming materials, thus promoting explosive volcanism. It is crucial that Hydrothermal Alteration, which develops over months to years, is monitored at dome-forming volcanoes and is incorporated into real-time hazard assessments.
Shaun L L Barker - One of the best experts on this subject based on the ideXlab platform.
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Quantifying the role of Hydrothermal Alteration in creating geothermal and epithermal mineral resources: The Ohakuri ignimbrite (Taupō Volcanic Zone, New Zealand)
Journal of Volcanology and Geothermal Research, 2019Co-Authors: Michael Heap, H. Albert Gilg, Darren Gravley, Ben Kennedy, Elisabeth Bertolett, Shaun L L BarkerAbstract:Hydrothermal fluids can alter the chemical and physical properties of the materials through which they pass and can therefore modify the efficiency of fluid circulation. The role of Hydrothermal Alteration in the development of geothermal and epithermal mineral resources, systems that require the efficient Hydrothermal circulation provided by fracture networks, is investigated here from a petrophysical standpoint using samples collected from a well exposed and variably altered palaeo-Hydrothermal system hosted in the Ohakuri ignimbrite deposit in the Taupō Volcanic Zone (New Zealand). Our new laboratory data show that, although quartz and adularia precipitation reduces matrix porosity and permeability, it increases the uniaxial compressive strength, Young’s modulus, and propensity for brittle behaviour. The fractures formed in highly altered rocks containing quartz and adularia are also more planar than those formed in their less altered counterparts. All of these factors combine to enhance the likelihood that a silicified rock-mass will host permeability-enhancing fractures. Indeed, the highly altered silicified rocks of the Ohakuri ignimbrite deposit are much more fractured than less altered outcrops. By contrast, smectite Alteration at the margins of the Hydrothermal system does not significantly increase strength or Young’s modulus, or significantly decrease permeability, and creates a relatively unfractured rock-mass. Using our new laboratory data, we provide permeability modelling that shows that the equivalent permeability of a silicified rock-mass will be higher than that of a less altered rock-mass or a rock-mass characterised by smectite Alteration, the latter of which provides a low-permeability cap required for an economically viable Hydrothermal resource. Our new data show, using a petrophysical approach, how Hydrothermal Alteration can produce rock-masses that are both suitable for geothermal energy exploitation (high-permeability reservoir and low-permeability cap) and more likely to host high-grade epithermal mineral veins, such as gold and silver (localised fluid flow).
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Hydrothermal Alteration revealed by apatite luminescence and chemistry a potential indicator mineral for exploring covered porphyry copper deposits
Economic Geology, 2016Co-Authors: Farhad Bouzari, Thomas Bissig, Craig J R Hart, Shaun L L BarkerAbstract:Apatite is a common resistate mineral occurring in a range of host rocks and ore-related Hydrothermal Alteration assemblages. Apatite in several porphyry copper deposits in British Columbia has a unique set of physical and compositional characteristics that can be used to evaluate the chemical conditions of magmas that formed the causative intrusions or associated Hydrothermal Alteration. Apatite under visible light and SEM shows no notable variations between unaltered and altered varieties but cathodoluminescence reveals significant differences. Apatite in unaltered rocks displays yellow, yellow-brown, and brown luminescence, whereas in K silicate-altered rocks apatite displays a characteristic green luminescence. The green-luminescent apatite replaces yellow- or brown-luminescent apatite and locally overgrows it. Apatite occurring with muscovite (i.e., phyllic)-altered rocks displays characteristic gray luminescence. The chemistry of apatite, as determined by electron microprobe and laser ICP-MS analyses, directly reflects its Alteration and luminescence. The unaltered yellow-luminescent apatite has high concentrations of Mn (0.3–0.5 wt % MnO) and a high Mn/Fe ratio (>1), whereas the brown-luminescent apatite has low Mn, but higher concentrations of S and REE + Y. The green K silicate Alteration-related luminescence is caused by lower Mn/Fe ratios (ca. 1) along with depletions of other trace elements such as Cl, S, and Na. Gray-luminescent apatite occurring with muscovite-altered rocks results from significant Mn loss ( The correlation between apatite texture, luminescence, and chemical composition with the type and intensity of porphyry Alteration offers a potentially fast and effective method to utilize it as an indicator for porphyry mineralization in a range of exploration materials including soils, regoliths, and heavy mineral concentrates from glacial and fluvial materials.
Mazlan Hashim - One of the best experts on this subject based on the ideXlab platform.
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identification of Hydrothermal Alteration minerals associated with geothermal system using aster and hyperion satellite data a case study from yankari park ne nigeria
Geocarto International, 2019Co-Authors: Aliyu Jaafar Abubakar, Mazlan Hashim, Amin Beiranvand PourAbstract:Concealed and fossilized geothermal systems are not characterized by obvious surface manifestations like hotsprings and fumaroles, therefore, could not be easily identifiable using conventional techniques. In this investigation, the applicability of Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Hyperion data-sets were evaluated in discriminating Hydrothermal Alteration minerals associated with geothermal systems as a proxy in identifying subtle Geothermal systems at Yankari Park, Nigeria. Feature-oriented principal component selection, spectral angle mapper, linear spectral unmixing were applied to ASTER data based on spectral characteristics of Hydrothermal Alteration key minerals for a systematic selective extraction of the information of interest. Analytical imaging and geophysics-developed processing methods were applied to Hyperion data for mapping iron oxide/hydroxide minerals and clay mineral assemblages in Hydrothermal Alteration zones. The results indicate that ASTER and Hyperion could be complemented for reconnaissance stage of targeting subtle Alteration mineral assemblages associated with geothermal systems.
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detection of Hydrothermal Alteration zones in a tropical region using satellite remote sensing data bau goldfield sarawak malaysia
Ore Geology Reviews, 2013Co-Authors: Amin Beiranvand Pour, Mazlan Hashim, John Van GenderenAbstract:Abstract Remote sensing for geology in tropical environments is very challenging, because of the dense vegetation cover and the problem of persistent cloud cover. In this research paper, we have investigated and demonstrated the detection of Hydrothermal Alteration zones and structural elements associated with intrusion-related gold mineralization using various types of remote sensing data in the Bau gold mining district in the State of Sarawak, East Malaysia, on the island of Borneo. The climate of Bau is tropical with persistent cloud cover and very dense vegetation ground. Geological analyses coupled with remote sensing data were used to detect Hydrothermally altered rocks and structural elements associated with gold mineralization in the Bau area. Landsat Enhanced Thematic Mapper+ (ETM+), Hyperion and Phased Array type L-band Synthetic Aperture Radar (PALSAR) data were used to carry out lithological–structural mapping of the mineralized zones in the study area and surrounding terrain. Hydrothermal Alteration zones were detected along the SSW to NNE structural trend of the Tai Parit fault that corresponds with the occurrence of other gold mineralization in the Bau Limestone. The results show that the known gold prospects and potential areas of mineralization are recognizable by the methods used, despite limited bedrock exposure. The approach used in this study is broadly applicable to the detection of gold mineralization using ETM+, Hyperion and PALSAR data in tropical/sub-tropical regions.
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identification of Hydrothermal Alteration minerals for exploring of porphyry copper deposit using aster data se iran
Journal of Asian Earth Sciences, 2011Co-Authors: Amin Beiranvand Pour, Mazlan HashimAbstract:The NW–SE trending Central Iranian Volcanic Belt hosts many well-known porphyry copper deposits in Iran. It becomes an interesting area for remote sensing investigations to explore the new prospects of porphyry copper and vein type epithermal gold mineralization. Two copper mining districts in southeastern segment of the volcanic belt, including Meiduk and Sarcheshmeh have been selected in the present study. The performance of Principal Component Analysis, band ratio and Minimum Noise Fraction transformation has been evaluated for the visible and near infrared (VNIR) and, shortwave infrared (SWIR) subsystems of ASTER data. The image processing techniques indicated the distribution of iron oxides and vegetation in the VNIR subsystem. Hydrothermal Alteration mineral zones associated with porphyry copper mineralization identified and discriminated based on distinctive shortwave infrared (SWIR) properties of the ASTER data in a regional scale. These techniques identified new prospects of porphyry copper mineralization in the study areas. The spatial distribution of Hydrothermal Alteration zones has been verified by in situ inspection, X-ray diffraction (XRD) analysis, and spectral reflectance measurements. Results indicated that the integration of the image processing techniques has a great ability to obtain significant and comprehensive information for the reconnaissance stages of porphyry copper exploration in a regional scale. The results of this research can assist exploration geologists to find new prospects of porphyry copper and gold deposits in the other virgin regions before costly detailed ground investigations. Consequently, the introduced image processing techniques can create an optimum idea about possible location of the new prospects.
Antonio F. F. Santos - One of the best experts on this subject based on the ideXlab platform.
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Temporal evolution of the giant Salobo IOCG deposit, Carajás Province (Brazil): constraints from paragenesis of Hydrothermal Alteration and U-Pb geochronology
'Springer Science and Business Media LLC', 2020Co-Authors: Gustavo H. C. De Melo, Lena V. S. Monteiro, Roberto P Xavier, Carolina P. N. Moreto, Erika S. B. Santiago, Benevides Aires, Andrew S Dufrane, Antonio F. F. SantosAbstract:FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOThe giant Salobo copper-gold deposit is located in the Carajás Province, Amazon Craton. Detailed drill core description, petrographical studies, and U-Pb SHRIMP IIe and LA-ICP-MS geochronology unravel its evolution regarding the host rocks, Hydrothermal Alteration and mineralization. Within the Cinzento Shear Zone, the deposit is hosted by orthogneisses of the Mesoarchean Xingu Complex (2950 ± 25 and 2857 ± 6.7 Ma) and of the Neoarchean Igarapé Gelado suite (2763 ± 4.4 Ma), which are crosscut by the Old Salobo granite. Remnants of the Igarapé Salobo metavolcanic-sedimentary sequence are represented by a quartz mylonite with detrital zircon populations (ca. 3.1–3.0, 2.95, 2.86, and 2.74 Ga). High-temperature calcic-sodic Hydrothermal Alteration (hastingsite-actinolite) was followed by silicification, iron-enrichment (almandine-grunerite-magnetite), tourmaline formation, potassic Alteration with biotite, copper-gold ore formation, and later Fe-rich hydrated silicate Alteration. Myrmekitic bornite-chalcocite and magnetite comprise the bulk of copper-gold ore. All these Alteration assemblages have been overprinted by post-ore hematite-bearing potassic and propylitic Alteration, which is also recognized in the Old Salobo granite. In the central zone of the deposit the mylonitized Igarapé Gelado suite rocks yield an age of 2701 ± 30 Ma. Zircon ages of 2547 ± 5.3 and 2535 ± 8.4 Ma were obtained for the Old Salobo granite and for the high-grade copper ore, respectively. A U-Pb LA-ICP-MS monazite age (2452 ± 14 Ma) from the copper-gold ore indicates Hydrothermal activity and overprinting in the Siderian. Therefore, a protracted tectono-thermal event due to the reactivation of the Cinzento Shear Zone is proposed for the evolution of the Salobo deposit525709732FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO573733/2008-22009/18371-02013/25659-5481969/2013-6308365/2014-
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temporal evolution of the giant salobo iocg deposit carajas province brazil constraints from paragenesis of Hydrothermal Alteration and u pb geochronology
Mineralium Deposita, 2017Co-Authors: Gustavo H. C. Demelo, Lena V. S. Monteiro, Roberto P Xavier, Carolina P. N. Moreto, Erika S. B. Santiago, Benevides Aires, Andrew S Dufrane, Antonio F. F. SantosAbstract:The giant Salobo copper-gold deposit is located in the Carajas Province, Amazon Craton. Detailed drill core description, petrographical studies, and U-Pb SHRIMP IIe and LA-ICP-MS geochronology unravel its evolution regarding the host rocks, Hydrothermal Alteration and mineralization. Within the Cinzento Shear Zone, the deposit is hosted by orthogneisses of the Mesoarchean Xingu Complex (2950 ± 25 and 2857 ± 6.7 Ma) and of the Neoarchean Igarape Gelado suite (2763 ± 4.4 Ma), which are crosscut by the Old Salobo granite. Remnants of the Igarape Salobo metavolcanic-sedimentary sequence are represented by a quartz mylonite with detrital zircon populations (ca. 3.1–3.0, 2.95, 2.86, and 2.74 Ga). High-temperature calcic-sodic Hydrothermal Alteration (hastingsite-actinolite) was followed by silicification, iron-enrichment (almandine-grunerite-magnetite), tourmaline formation, potassic Alteration with biotite, copper-gold ore formation, and later Fe-rich hydrated silicate Alteration. Myrmekitic bornite-chalcocite and magnetite comprise the bulk of copper-gold ore. All these Alteration assemblages have been overprinted by post-ore hematite-bearing potassic and propylitic Alteration, which is also recognized in the Old Salobo granite. In the central zone of the deposit the mylonitized Igarape Gelado suite rocks yield an age of 2701 ± 30 Ma. Zircon ages of 2547 ± 5.3 and 2535 ± 8.4 Ma were obtained for the Old Salobo granite and for the high-grade copper ore, respectively. A U-Pb LA-ICP-MS monazite age (2452 ± 14 Ma) from the copper-gold ore indicates Hydrothermal activity and overprinting in the Siderian. Therefore, a protracted tectono-thermal event due to the reactivation of the Cinzento Shear Zone is proposed for the evolution of the Salobo deposit.
