In the framework of a mineral system approach,a combination of components is required to develop a mineral system.This includes the whole-lithosphere architecture,which controls the transport of ore-forming fluids,and...In the framework of a mineral system approach,a combination of components is required to develop a mineral system.This includes the whole-lithosphere architecture,which controls the transport of ore-forming fluids,and favorable tectonic and geodynamic processes,occurring at various spatial and temporal scales,that influence the genesis and evolution of ore-forming fluids(Huston et al.,2016;Groves et al.,2018;Davies et al.,2020).Knowledge of the deep structural framework can advance the understanding of the development of a mineral system and the emplacement of mineral deposits.Deep geophysical exploration carried out with this aim is increasingly important for targeting new ore deposits in unexplored and underexplored regions(Dentith et al.,2018;Dentith,2019).展开更多
The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization ...The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.展开更多
The Daheishan supergiant porphyry molybdenum deposit(also referred to as the Daheishan deposit)is the second largest molybdenum deposit in Asia and ranks fifth among the top seven molybdenum deposits globally with tot...The Daheishan supergiant porphyry molybdenum deposit(also referred to as the Daheishan deposit)is the second largest molybdenum deposit in Asia and ranks fifth among the top seven molybdenum deposits globally with total molybdenum reserves of 1.65 billion tons,an average molybdenum ore grade of 0.081%,and molybdenum resources of 1.09 million tons.The main ore body is housed in the granodiorite porphyry plutons and their surrounding inequigranular granodiorite plutons,with high-grade ores largely located in the ore-bearing granodiorite porphyries in the middle-upper part of the porphyry plutons.Specifically,it appears as an ore pipe with a large upper part and a small lower part,measuring about 1700 m in length and width,extending for about 500 m vertically,and covering an area of 2.3 km^(2).Mineralogically,the main ore body consists of molybdenite,chalcopyrite,and sphalerite horizontally from its center outward and exhibits molybdenite,azurite,and pyrite vertically from top to bottom.The primary ore minerals include pyrite and molybdenite,and the secondary ore minerals include sphalerite,chalcopyrite,tetrahedrite,and scheelite,with average grades of molybdenum,copper,sulfur,gallium,and rhenium being 0.081%,0.033%,1.67%,0.001%,and 0.0012%,respectively.The ore-forming fluids of the Daheishan deposit originated as the CO_(2)-H_(2)O-NaCl multiphase magmatic fluid system,rich in CO_(2)and bearing minor amounts of CH4,N2,and H2S,and later mixed with meteoric precipitation.In various mineralization stages,the ore-forming fluids had homogenization temperatures of>420℃‒400℃,360℃‒350℃,340℃‒230℃,220℃‒210℃,and 180℃‒160℃and salinities of>41.05%‒9.8%NaCleqv,38.16%‒4.48%NaCleqv,35.78%‒4.49%NaCleqv,7.43%NaCleqv,and 7.8%‒9.5%NaCleqv,respectively.The mineralization of the Daheishan deposit occurred at 186‒167 Ma.The granites closely related to the mineralization include granodiorites(granodiorite porphyries)and monzogranites(monzogranite porphyries),which were mineralized after magmatic evolution(189‒167 Ma).Moreover,these mineralization-related granites exhibit low initial strontium content and high initial neodymium content,indicating that these granites underwent crust-mantle mixing.The Daheishan deposit formed during the Early-Middle Jurassic,during which basaltic magma underplating induced the lower-crust melting,leading to the formation of magma chambers.After the fractional crystallization of magmas,ore-bearing fluids formed.As the temperature and pressure decreased,the ore-bearing fluids boiled drops while ascending,leading to massive unloading of metal elements.Consequently,brecciated and veinlet-disseminated ore bodies formed.展开更多
The Shwebontha prospect area is situated in the Central Volcanic Belt,central Myanmar,where the well-known Sagaing Fault serves as its eastern boundary.This study aims to document key the mineralogy,host rock geochemi...The Shwebontha prospect area is situated in the Central Volcanic Belt,central Myanmar,where the well-known Sagaing Fault serves as its eastern boundary.This study aims to document key the mineralogy,host rock geochemistry and ore mineralizing fluids.The mineralization,hosted by Upper Oligocene to Middle Miocene rhyolites,displays a strong lithological control.Mineralization is characterized by gold-bearing silicified massive ore and chalcedonic quartz veins in which sulfides are clustered and disseminated not only in quartz gangue but also in rhyolite host rocks.The significant ore minerals in the mineralized veins include pyrite,sphalerite,galena,chalcopyrite,and gold.Common hydrothermal alterations such as silicic,argillic and propylitic alteration types are recognized.According to the fluid inclusion data and interpretation,ore mineralizing fluids in the research area are characterized by formation temperatures of 260-280℃ and salinity of 0.35-2.41%wt.NaCl eq.respectively.Mixing of hydrothermal fluids was generally considered to be an effective mechanism for ore transport and deposition.展开更多
The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mi...The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mineralization system is of great importance to the discovery of new type ore deposits. ① The understanding of the relationship among various ore deposit types within a mineralization system in a region can help us to locate the unknown ore deposit types from the known ore deposit types, evidence that has been proved in the mineral prospecting history of ore belts in the middle and lower reaches of the Yangtze River, China. ② The understanding of the spatial structure of a mineralization system, especially of the vertical zonation, is helpful for the discovery of the concealed ore deposit types. ③ Clarifying the temporal structure of a mineralization system, including the iteration relationship between the mineral deposit types in the mineralization, leads to the location of the missing mineralization chains from the known mineralization chains (mineral deposit type), a method often proved to be effective in the magmatic hydrothermal mineralization system.④ Clarifying the factors restraining the diversity of mineral deposit types in mineralization system leads to the discovery of the potential of new type mineral deposits in relevant region. ⑤ Studying new mineralization setting and new ore forming processes leads to discovery of new type mineral deposit. More probabilities of discovery of new type mineral deposits are present in biogenic mineralization system, deep sea mineralization system, low temperature mineralization system, tectonic mineralization system and superimposed mineralization system.展开更多
Objective The Miao'ershan-Yuechengling composite granite, located in northern Guangxi at the western section of the Nanling Range, is a multi-period and multi-stage composite pluton with an exposed area of more than...Objective The Miao'ershan-Yuechengling composite granite, located in northern Guangxi at the western section of the Nanling Range, is a multi-period and multi-stage composite pluton with an exposed area of more than 3000 km2 (Fig. 1). Paleozoic and Proterozoic strata are exposed around it, and magmatic activities mainly occurred during the Caledonian and Indosinian periods. Till now, more than one hundred W-Sn-Mo-Pb-Zn-Cu (U) deposits and ore occurrences have been discovered along the inner and outer contact zones of this granite. Through recent years' research, we infer that this area is not only a preferred area for studying granite and mineralization in Caledonian and lndosinian periods, but also a potential Caledonian- lndosinian ore-concentrated area.展开更多
The Bangong Lake-Nujiang River metallogenic belt is located between the Qiangtang Block and Lhasa Block, and the Duolong ore concentration area is located in the western section of the Bangong Lake-Nujiang River metal...The Bangong Lake-Nujiang River metallogenic belt is located between the Qiangtang Block and Lhasa Block, and the Duolong ore concentration area is located in the western section of the Bangong Lake-Nujiang River metallogenic belt. Till now, several large and super large copper-gold deposits, such as Duobuza, Bolong, Dibaonamugang, Naruo and Rongna deposits have been discovered in this area, mainly porphyry copper-gold ones.展开更多
This studied gold ore belt is giant and very important in China. Its regional tectonics and evolutional process are complicated. There are a few of view points on its geotec-tonic attribute in the Mesozoic and Cenozoi...This studied gold ore belt is giant and very important in China. Its regional tectonics and evolutional process are complicated. There are a few of view points on its geotec-tonic attribute in the Mesozoic and Cenozoic eras and on the type of its some gold ore deposits, especially, on one hosted in the pre-diwa geological bodies. On the basis of the diwa theory, the author discussed the regionalization, and its evolutional process, and some features of diwa tectono-magmatism and diwa type of gold mineralization in this belt. The author proposed that(1)the main body zone is a part of the diwa regime in the Mesozoic and Cenozoic eras, and(2)the diwa tectono-magmatism had a series of features such as universalism and violence, newborn, reform and superimposition, joining, inheritance, multiperiodic activity, complica-tion and so on. The gold mineralization formed in the diwa regime are called diwa type of golddeposits.In this paper the diwa type of endogenetic gold mineralization products hosted in the pre-diwa geological bodies in this zone is discussed in detail.展开更多
A direct hydrometallurgical route for nickel and molybdenum extraction from a nickel-molybdenum (Ni-Mo) ore using pressure acid leaching was studied. The nickel and molybdenum were extracted by acid leaching under o...A direct hydrometallurgical route for nickel and molybdenum extraction from a nickel-molybdenum (Ni-Mo) ore using pressure acid leaching was studied. The nickel and molybdenum were extracted by acid leaching under oxygen pressure. Compared with traditional roasting methods, this hydrometallurgical method eliminates SO2 and As203 emission (the Ni-Mo ore containing 15%-25% S). Compared with existing alkali leaching recovery of molybdenum process, almost all the nickel and considerable molybdenum were extracted in the acid leaching process. Under oxygen pressure conditions, almost all the nickel and a substantial part of the molybdenum were dissolved into the acid leaching liquor and the other part of the molybdenum was left in the acid leach residue. The acid leach residue was further leached under alkaline (NaOH) conditions. Under optimal experimental conditions, the extraction rates nickel and molybdenum reached 97% and 96%, respectively.展开更多
The bioleaching of molybdenum from its sulfide ore using a Mo-resistant thermophilic bacterium sulfolobus metallics combined with a membrane biological reactor(MBR) was studied.The experimental results showed that t...The bioleaching of molybdenum from its sulfide ore using a Mo-resistant thermophilic bacterium sulfolobus metallics combined with a membrane biological reactor(MBR) was studied.The experimental results showed that the concentration of Mo can be controlled by filter of the membrane in MBR and the toxicity of Mo to microorganism is decreased in the process of bioleaching.It was also evidenced that there were different leaching rates of Ni and Mo when the concentration of Mo was different.After leaching for 20 d in the MBR at Mo concentration of 395 mg/L,the leaching rates of Ni and Mo reached the maximum of 79.57% and 56.23% respectively under the conditions of 100 g/L of mineral density,65 ℃,pH=2 and 1.0 L/min of the aeration rate.While 75.59% Ni and 54.33% Mo were leached out in column without membrane under the same conditions.展开更多
To extract molybdenum and nickel from the roasted Ni-Mo ore, a process of hydrochloric acid leaching, sulphation roasting and water leaching was investigated. The results showed that this process could get a high leac...To extract molybdenum and nickel from the roasted Ni-Mo ore, a process of hydrochloric acid leaching, sulphation roasting and water leaching was investigated. The results showed that this process could get a high leaching rate of Mo and Ni. Under the optimum conditions of hydrochloric acid leaching (roasted Ni-Mo ore leached with 0.219 mL/g hydrochloric acid addition at 65 ℃ for 30 min with a L/S ratio of 3 mL/g), sulphation roasting (51.9% sulfiaric acid addition, roasting temperature 240 ℃ for 1 h), followed by leaching with the first stage hydrochloric acid leaching solution at 95 ℃ for 2 h, the leaching rates of Mo and Ni reached 95.8% and 91.3%, respectively.展开更多
Locating the mineral processing plant near a mine is the most important parameter that affects the whole process.Many factors,and their preferences,should be considered in this stage.The factors include economical,geo...Locating the mineral processing plant near a mine is the most important parameter that affects the whole process.Many factors,and their preferences,should be considered in this stage.The factors include economical,geological,technical,environmental and tectonic parameters.A multi-criteria decision making method is necessary to rank the alternatives.In this paper we describe how plant location is selected by using the Analytic Hierarchy Process(AHP).This method,with eight criteria,was used to select a location for the mineral processing plant at the Sangan iron ore mine(phase 1).Three alternatives for the processing plant were evaluated.The main criteria were distance from the mine,access to heavy machinery transport,the amount of excavation required for grading,bed mixture capacity,belt conveyor length,distance from the tailing dam,distance from the waste dumps and surface water diversion requirements.Finally,the alternatives were ranked and the best location was proposed.展开更多
The Gejiu (个旧) deposit is a superlarge tin-copper polymetallic ore-forming concentration area characterized by excellent metallogenic geological settings and advantageous ore-controlling factors. The deposit displ...The Gejiu (个旧) deposit is a superlarge tin-copper polymetallic ore-forming concentration area characterized by excellent metallogenic geological settings and advantageous ore-controlling factors. The deposit displays diverse mineralization properties due to different minerals and mineral deposit types. Based on the principal metallogenic factors, metallogenic mechanisms, mineralized components, and occurrence of mineral deposits or ore bodies, the Gejiu mineral district can be divided into 2 combinations of metallogenic series, 4 metallogenic series, 8 subseries, and 27 mineral deposit types. Spatial zonality is evident. The distribution regularity of the elements in both plane and section is Be-W, Sn (Cu, Mo, Bi, Be)-Sn, Pb, Ag-Pb, Zn around a granitic intrusion. The metallogenic epoch is mainly concentrated in the late Yanshanian. During this period, large-scale metallogenic processes related to movement caused by tectonics and magmatism occurred, and a series of magmatic hydrothermal deposits formed. The ore-forming processes can be divided into 4 stages: the silicate stage, the oxide stage, the sulphide stage, and the carbonate stage. Based on the orderliness and diversity (in terms of time, space, and genesis) of the mineralization, the authors have developed a comprehensive spectrum of ore deposits in the Gejiu area. This newly proposed diversity of mineralization and the spectrum developed in this work are useful not only for interpreting the genesis of the Gejiu deposit but also for improving mineral exploration in the area, and in particular, for finding large deposits.展开更多
Mineral dissemination and pore space distribution in ore particles are important features that influence heap leaching performance. To quantify the mineral dissemination and pore space distribution of an ore particle,...Mineral dissemination and pore space distribution in ore particles are important features that influence heap leaching performance. To quantify the mineral dissemination and pore space distribution of an ore particle, a cylindrical copper oxide ore sample (I center dot 4.6 mm x 5.6 mm) was scanned using high-resolution X-ray computed tomography (HRXCT), a nondestructive imaging technology, at a spatial resolution of 4.85 mu m. Combined with three-dimensional (3D) image analysis techniques, the main mineral phases and pore space were segmented and the volume fraction of each phase was calculated. In addition, the mass fraction of each mineral phase was estimated and the result was validated with that obtained using traditional techniques. Furthermore, the pore phase features, including the pore size distribution, pore surface area, pore fractal dimension, pore centerline, and the pore connectivity, were investigated quantitatively. The pore space analysis results indicate that the pore size distribution closely fits a log-normal distribution and that the pore space morphology is complicated, with a large surface area and low connectivity. This study demonstrates that the combination of HRXCT and 3D image analysis is an effective tool for acquiring 3D mineralogical and pore structural data.展开更多
The characteristics of aerosol flotation, which include the effect of the concentration and particle size of kerosene aerosol on the molybdenum (Mo) flotation index and the effect of kerosene aerosol dosing method o...The characteristics of aerosol flotation, which include the effect of the concentration and particle size of kerosene aerosol on the molybdenum (Mo) flotation index and the effect of kerosene aerosol dosing method on the kerosene dosage and flotation time, were studied in the flotation of low-grade refractory molybdenum ores using kerosene aerosol. The results revealed that the particle size and concentration of kerosene aerosol had little effect on the Mo grade but had significant effect on the Mo recovery. A smaller particle size and a lower con-centration of kerosene aerosol were beneficial to the Mo aerosol flotation. For the received Mo ore samples, the optimized particle size of kerosene aerosol was 0.3-2 μm and the optimized aerosol concentration was 14 mg/L. The compressed air atomizer had a more uniform dis-tribution of aerosol particles than the ultrasonic atomizer, and the aerosol concentration was controlled easily, so the compressed air atomizer was more suitable for the research of aerosol flotation. Compared with conventional flotation in which kerosene was directly added into the ore pulp, the flotation time was reduced by ~30%, and the dosage was decreased by ~20% in aerosol flotation, while the Mo flotation index was similar.展开更多
The newly discovered Changkeng Au-Ag deposit is a new type of sediment-hostedprecious metal deposit. Most of the previous researchers believed that the deposit was formed bymeteoric water convection. By using a high v...The newly discovered Changkeng Au-Ag deposit is a new type of sediment-hostedprecious metal deposit. Most of the previous researchers believed that the deposit was formed bymeteoric water convection. By using a high vacuum quadrupole gas mass spectrometric system, ninelight hydrocarbons have been recognized in the fluid inclusions in ore minerals collected from theChangkeng deposit. The hydrocarbons are composed mainly of saturated alkanes C_(1-4) and unsaturatedalkenes C_(2-4) and aromatic hydrocarbons, in which the alkanes are predominant, while the contentsof alkenes and aromatic hydrocarbons are very low. The sum alka/sum alke ratio of most samples ishigher than 100, suggesting that those hydrocarbons are mainly generated by pyrolysis of kerogens insedimentary rocks caused by water-rock interactions at medium-low temperatures, and themetallogenic processes might have not been affected by magmatic activity. A thermodynamiccalculation shows that the light hydrocarbons have reached chemical equilibrium at temperatureshigher than 200 deg C, and they may have been generated in the deep part of sedimentary basins(e.g., the Sanzhou basin) and then be transported by ore-forming fluids to a shallow position of thebasin via a long distance. Most of the organic gases are generated by pyrolysis of the type IIkerogens (kukersite) in sedimentary host rocks, only a few by microorganism activity. Thecompositions and various parameters of light hydrocarbons in gold ores are quite similar to those insilver ores, suggesting that the gold and silver ores may have similar metallogenic processes.Based on the compositions of organic gases in fluid inclusions, the authors infer that the Changkengdeposit may be of a tectonic setting of continental rift. The results of this study support fromone aspect the authors' opinion that the Changkeng deposit is not formed by meteoric waterconvection, and that its genesis has a close relationship with the evolution of the Sanzhou basin,so it belongs to the sedimentary hot brine transformed deposit.展开更多
The Piaotang deposit is one of the largest vein-type W-polymetallic deposits in southern Jiangxi Province,South China.The coexistence of wolframite and cassiterite is an important feature of the deposit.Based on detai...The Piaotang deposit is one of the largest vein-type W-polymetallic deposits in southern Jiangxi Province,South China.The coexistence of wolframite and cassiterite is an important feature of the deposit.Based on detailed petrographic observations,microthermometry of fluid inclusions in wolframite,cassiterite and intergrown quartz was undertaken.The inclusions in wolframite were observed by infrared microscope,while those in cassiterite and quartz were observed in visible light.The fluid inclusions in wolframite can be divided into two types:aqueous inclusions with a large vapor-phase proportion and aqueous inclusions with a small vapor-phase ratio.The homogenization temperature(Th)of inclusions in wolframite with large vapor-phase ratios ranged from 280℃ to 390℃,with salinity ranging from 3.1 to 7.2 wt%NaCl eq.In contrast,the Th values of inclusions with small vapor-phase ratios ranged from 216℃ to 264℃,with salinity values ranging from 3.5 to 9.3 wt%NaCl eq.T_(h) values of primary inclusions in cassiterite ranged from 316℃ to 380℃,with salinity ranging from 5.4 to 9.3 wt%NaCl eq.T_(h) values for primary fluid inclusions in quartz ranged from 162℃ to 309℃,with salinity values ranging from 1.2 to 6.7 wt%NaCl eq.The results show that the formation conditions of wolframite,cassiterite and intergrown quartz are not uniform.The evolutionary processes of fluids related to these three kinds of minerals are also significantly different.Intergrown quartz cannot provide the depositional conditions of wolframite and cassiterite.The fluids related to tungsten mineralization for the NaCl-H_(2)O system had a medium-to-high temperature and low salinity,while the fluids related to tin mineralization for the NaCl-H_(2)O system had a high temperature and medium-to-low salinity.The results of this study suggest that fluid cooling is the main mechanism for the precipitation of tungsten and tin.展开更多
The effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores was carried out by phase analysis means of XRD, optical microscopy and SEM-EDS. The resul...The effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores was carried out by phase analysis means of XRD, optical microscopy and SEM-EDS. The results indicated that at ambient temperature, the easily leached copper oxide minerals were completely dissolved, while the bonded copper minerals were insoluble. At lukewarm temperature of 40℃, it was mainly the dissolution of copper in isomorphism state. With increasing temperature to 60℃, the copper leaching rate in the adsorbed state was significantly accelerated. In addition, when the temperature increased to 80℃, the isomorphic copper was completely leached, leaving 11.2% adsorbed copper un-leached. However, the copper in feldspar-quartz-copper-iron colloid state was not dissolved throughout the leaching process. Overall, the leaching rates of copper in different copper minerals decreased in the order: malachite, pseudo-malachite > chrysocolla > copper-bearing chlorite > copper-bearing muscovite > copper-bearing biotite > copper-bearing limonite > feldspar-quartz-copper-iron colloid.展开更多
The porphyry copper belt in the Geza island arc in southwestern China is the only Indosinian porphyry copper metallogenic belt that has been discovered and evaluated so far.The Pulang porphyry copper deposit(also refe...The porphyry copper belt in the Geza island arc in southwestern China is the only Indosinian porphyry copper metallogenic belt that has been discovered and evaluated so far.The Pulang porphyry copper deposit(also referred to as the Pulang deposit)in this area has proven copper reserves of 5.11×106 t.This deposit has been exploited on a large scale using advanced mining methods,exhibiting substantial economic benefit.Based on many research results of previous researchers and the authors’team,this study proposed the following key insights.(1)The Geza island arc was once regarded as an immature island arc with only andesites and quartz diorite porphyrites occurring.This understanding was overturned in this study.Acidic endmember components such as quartz monzonite porphyries and quartz monzonite porphyries have been identified in the Geza island arc,and the mineralization is mainly related to the magmatism of quartz monzonite porphyries.(2)Complete porphyry orebodies and large vein orebodies have developed in the Pulang deposit.Main orebody KT1 occurs in the transition area between the potassium silicate alteration zone of quartz monzonite porphyries and the sericite-quartz alteration zone.Most of them have developed in the potassium silicate alteration zone.The main orebody occurs as large lenses at the top of the hanging wall of rock bodies,with an engineering-controlled length of 1920 m and thickness of 32.5‒630.29 m(average:187.07 m).It has a copper grade of 0.21%-1.56%(average:0.42%)and proven copper resources of 5.11×10^(6) t,which are associated with 113 t of gold,1459 t of silver,and 170×10^(3) t of molybdenum.(3)Many studies on diagenetic and metallogenic chronology,isotopes,and fluid inclusions have been carried out for the Pulang deposit,including K-Ar/Ar-Ar dating of monominerals(e.g.,potassium feldspars,biotites,and amphiboles),zircon U-Pb dating,and molybdenite Re-Os dating.The results show that the porphyries in the Pulang deposit are composite plutons and can be classified into pre-mineralization quartz diorite porphyrites,quartz monzonite porphyries formed during the mineralization,and post-mineralization granite porphyries,which were formed at 223±3.7 Ma,218±4 Ma,and 207±3.9 Ma,respectively.The metallogenic age of the Pulang deposit is 213‒216 Ma.(4)The petrogeochemical characteristics show that the Pulang deposit has the characteristics of volcanic arc granites.The calculation results of trace element contents in zircons show that quartz monzonite porphyries and granite porphyries have higher oxygen fugacity.The isotopic tracing results show that the diagenetic and metallogenic materials were derived from mixed crust-and mantle-derived magmas.展开更多
Because of the low grade, high oxidation rate and the accumulation of little associated metal sulfide ore in the molybdenum concentrate during flotation, the Qingyang molybdenum ore is difficult to beneficiate. The ex...Because of the low grade, high oxidation rate and the accumulation of little associated metal sulfide ore in the molybdenum concentrate during flotation, the Qingyang molybdenum ore is difficult to beneficiate. The experimental studies of grinding fineness, the amount of roughing modifier, depressant and collector were completed. In the cleaning process, the contrast experiments of one regrinding, the regrinding and scrubbing, two-stage regrinding was carried. The result shows that the grade of molybdenum ore concentrate is 45.31%, the recovery is 65.98% and the rich ore ratio reaches 20.59% by the regrinding and scrubbing seven cleaning, the regrinding of concentrations from middling of molybdenum-sulfur separation. The regularly-concentrated material from the apparatus was as the middling products. Hence, ideal beneficiation index can be obtained with a rational mineral processing, which offers new beneficiating technology for the refractory low-grade molybdenum ore in China.展开更多
文摘In the framework of a mineral system approach,a combination of components is required to develop a mineral system.This includes the whole-lithosphere architecture,which controls the transport of ore-forming fluids,and favorable tectonic and geodynamic processes,occurring at various spatial and temporal scales,that influence the genesis and evolution of ore-forming fluids(Huston et al.,2016;Groves et al.,2018;Davies et al.,2020).Knowledge of the deep structural framework can advance the understanding of the development of a mineral system and the emplacement of mineral deposits.Deep geophysical exploration carried out with this aim is increasingly important for targeting new ore deposits in unexplored and underexplored regions(Dentith et al.,2018;Dentith,2019).
基金funded by the “Laboratoire de Recherche Ressources, Matériaux et Ecosystémes”, University of Carthage 7021 Zarzouna, Bizerte, Tunisia
文摘The Ain El Bey abandoned mine, in North-West Tunisia, fits into the geodynamic context of the European and African plate boundary. Ore deposit corresponds to veins and breccia of multiphase Cu–Fe-rich mineralization related to various hydrothermal fluid circulations. Petromineralogical studies indicate a rich mineral paragenesis with a minimum of seven mineralization phases and, at least, six pyrite generations. As is also the case for galena and native silver, native gold is observed for the first time as inclusion in quartz which opens up, thus, new perspectives for prospecting and evaluating the potential for noble metals associated with the mineralization. Scanning Electron Microscope--Energy Dispersive Spectroscopy and Transmission electron microscopy analyses show, in addition, a large incorporation of trace elements, including Ag and Au, in mineral structures such as fahlores(tetrahedrite-tennantite) and chalcopyrite ones. The mineral/mineral associations, used as geothermometers, gave estimated temperatures for the mineralizing fluids varying from 254 to 330 ℃ for phase Ⅲ, from 254 to 350 ℃ for phase Ⅳ, and from 200 to 300 ℃ for phases Ⅴ and Ⅵ. The seventh and last identified mineralization phase, marked by a deposit of native gold, reflects a drop in the mineralizing fluid’s temperature(< 200 ℃) compatible with boiling conditions. Such results open up perspectives for the development of precious metal research and the revaluation of the Cu–Fe ore deposit at the Ain El Bey abandoned mine, as well as at the surrounding areas fitting in the geodynamic framework of the Africa-Europe plate boundary.
基金This study was jointly funded by a project of the National Natural Science Foundation of China(42102087)a project of the China Postdoctoral Science Foundation(2022M712966)a key special project of the Ministry of Science and Technology of China(2021QZKK0304).
文摘The Daheishan supergiant porphyry molybdenum deposit(also referred to as the Daheishan deposit)is the second largest molybdenum deposit in Asia and ranks fifth among the top seven molybdenum deposits globally with total molybdenum reserves of 1.65 billion tons,an average molybdenum ore grade of 0.081%,and molybdenum resources of 1.09 million tons.The main ore body is housed in the granodiorite porphyry plutons and their surrounding inequigranular granodiorite plutons,with high-grade ores largely located in the ore-bearing granodiorite porphyries in the middle-upper part of the porphyry plutons.Specifically,it appears as an ore pipe with a large upper part and a small lower part,measuring about 1700 m in length and width,extending for about 500 m vertically,and covering an area of 2.3 km^(2).Mineralogically,the main ore body consists of molybdenite,chalcopyrite,and sphalerite horizontally from its center outward and exhibits molybdenite,azurite,and pyrite vertically from top to bottom.The primary ore minerals include pyrite and molybdenite,and the secondary ore minerals include sphalerite,chalcopyrite,tetrahedrite,and scheelite,with average grades of molybdenum,copper,sulfur,gallium,and rhenium being 0.081%,0.033%,1.67%,0.001%,and 0.0012%,respectively.The ore-forming fluids of the Daheishan deposit originated as the CO_(2)-H_(2)O-NaCl multiphase magmatic fluid system,rich in CO_(2)and bearing minor amounts of CH4,N2,and H2S,and later mixed with meteoric precipitation.In various mineralization stages,the ore-forming fluids had homogenization temperatures of>420℃‒400℃,360℃‒350℃,340℃‒230℃,220℃‒210℃,and 180℃‒160℃and salinities of>41.05%‒9.8%NaCleqv,38.16%‒4.48%NaCleqv,35.78%‒4.49%NaCleqv,7.43%NaCleqv,and 7.8%‒9.5%NaCleqv,respectively.The mineralization of the Daheishan deposit occurred at 186‒167 Ma.The granites closely related to the mineralization include granodiorites(granodiorite porphyries)and monzogranites(monzogranite porphyries),which were mineralized after magmatic evolution(189‒167 Ma).Moreover,these mineralization-related granites exhibit low initial strontium content and high initial neodymium content,indicating that these granites underwent crust-mantle mixing.The Daheishan deposit formed during the Early-Middle Jurassic,during which basaltic magma underplating induced the lower-crust melting,leading to the formation of magma chambers.After the fractional crystallization of magmas,ore-bearing fluids formed.As the temperature and pressure decreased,the ore-bearing fluids boiled drops while ascending,leading to massive unloading of metal elements.Consequently,brecciated and veinlet-disseminated ore bodies formed.
基金funded by AUN/SEED-Net(JICA program)in the fiscal year 2017-2021.
文摘The Shwebontha prospect area is situated in the Central Volcanic Belt,central Myanmar,where the well-known Sagaing Fault serves as its eastern boundary.This study aims to document key the mineralogy,host rock geochemistry and ore mineralizing fluids.The mineralization,hosted by Upper Oligocene to Middle Miocene rhyolites,displays a strong lithological control.Mineralization is characterized by gold-bearing silicified massive ore and chalcedonic quartz veins in which sulfides are clustered and disseminated not only in quartz gangue but also in rhyolite host rocks.The significant ore minerals in the mineralized veins include pyrite,sphalerite,galena,chalcopyrite,and gold.Common hydrothermal alterations such as silicic,argillic and propylitic alteration types are recognized.According to the fluid inclusion data and interpretation,ore mineralizing fluids in the research area are characterized by formation temperatures of 260-280℃ and salinity of 0.35-2.41%wt.NaCl eq.respectively.Mixing of hydrothermal fluids was generally considered to be an effective mechanism for ore transport and deposition.
文摘The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mineralization system is of great importance to the discovery of new type ore deposits. ① The understanding of the relationship among various ore deposit types within a mineralization system in a region can help us to locate the unknown ore deposit types from the known ore deposit types, evidence that has been proved in the mineral prospecting history of ore belts in the middle and lower reaches of the Yangtze River, China. ② The understanding of the spatial structure of a mineralization system, especially of the vertical zonation, is helpful for the discovery of the concealed ore deposit types. ③ Clarifying the temporal structure of a mineralization system, including the iteration relationship between the mineral deposit types in the mineralization, leads to the location of the missing mineralization chains from the known mineralization chains (mineral deposit type), a method often proved to be effective in the magmatic hydrothermal mineralization system.④ Clarifying the factors restraining the diversity of mineral deposit types in mineralization system leads to the discovery of the potential of new type mineral deposits in relevant region. ⑤ Studying new mineralization setting and new ore forming processes leads to discovery of new type mineral deposit. More probabilities of discovery of new type mineral deposits are present in biogenic mineralization system, deep sea mineralization system, low temperature mineralization system, tectonic mineralization system and superimposed mineralization system.
基金supported by the National Natural Science Foundation of China(grants No.41572058 and 41672065)
文摘Objective The Miao'ershan-Yuechengling composite granite, located in northern Guangxi at the western section of the Nanling Range, is a multi-period and multi-stage composite pluton with an exposed area of more than 3000 km2 (Fig. 1). Paleozoic and Proterozoic strata are exposed around it, and magmatic activities mainly occurred during the Caledonian and Indosinian periods. Till now, more than one hundred W-Sn-Mo-Pb-Zn-Cu (U) deposits and ore occurrences have been discovered along the inner and outer contact zones of this granite. Through recent years' research, we infer that this area is not only a preferred area for studying granite and mineralization in Caledonian and lndosinian periods, but also a potential Caledonian- lndosinian ore-concentrated area.
基金granted by the Geological Survey Program of China Geological Survey (Grant No.1212011086074 and 12120113036500)
文摘The Bangong Lake-Nujiang River metallogenic belt is located between the Qiangtang Block and Lhasa Block, and the Duolong ore concentration area is located in the western section of the Bangong Lake-Nujiang River metallogenic belt. Till now, several large and super large copper-gold deposits, such as Duobuza, Bolong, Dibaonamugang, Naruo and Rongna deposits have been discovered in this area, mainly porphyry copper-gold ones.
文摘This studied gold ore belt is giant and very important in China. Its regional tectonics and evolutional process are complicated. There are a few of view points on its geotec-tonic attribute in the Mesozoic and Cenozoic eras and on the type of its some gold ore deposits, especially, on one hosted in the pre-diwa geological bodies. On the basis of the diwa theory, the author discussed the regionalization, and its evolutional process, and some features of diwa tectono-magmatism and diwa type of gold mineralization in this belt. The author proposed that(1)the main body zone is a part of the diwa regime in the Mesozoic and Cenozoic eras, and(2)the diwa tectono-magmatism had a series of features such as universalism and violence, newborn, reform and superimposition, joining, inheritance, multiperiodic activity, complica-tion and so on. The gold mineralization formed in the diwa regime are called diwa type of golddeposits.In this paper the diwa type of endogenetic gold mineralization products hosted in the pre-diwa geological bodies in this zone is discussed in detail.
基金Projects(51174104,50874053)supported by the National Natural Science Foundation of ChinaProject(2009AA06Z106)supported by Hi-Tech Research and Development Program of ChinaProject(20115314110001)supported by Doctoral Fund of Ministry of Education of China
文摘A direct hydrometallurgical route for nickel and molybdenum extraction from a nickel-molybdenum (Ni-Mo) ore using pressure acid leaching was studied. The nickel and molybdenum were extracted by acid leaching under oxygen pressure. Compared with traditional roasting methods, this hydrometallurgical method eliminates SO2 and As203 emission (the Ni-Mo ore containing 15%-25% S). Compared with existing alkali leaching recovery of molybdenum process, almost all the nickel and considerable molybdenum were extracted in the acid leaching process. Under oxygen pressure conditions, almost all the nickel and a substantial part of the molybdenum were dissolved into the acid leaching liquor and the other part of the molybdenum was left in the acid leach residue. The acid leach residue was further leached under alkaline (NaOH) conditions. Under optimal experimental conditions, the extraction rates nickel and molybdenum reached 97% and 96%, respectively.
文摘The bioleaching of molybdenum from its sulfide ore using a Mo-resistant thermophilic bacterium sulfolobus metallics combined with a membrane biological reactor(MBR) was studied.The experimental results showed that the concentration of Mo can be controlled by filter of the membrane in MBR and the toxicity of Mo to microorganism is decreased in the process of bioleaching.It was also evidenced that there were different leaching rates of Ni and Mo when the concentration of Mo was different.After leaching for 20 d in the MBR at Mo concentration of 395 mg/L,the leaching rates of Ni and Mo reached the maximum of 79.57% and 56.23% respectively under the conditions of 100 g/L of mineral density,65 ℃,pH=2 and 1.0 L/min of the aeration rate.While 75.59% Ni and 54.33% Mo were leached out in column without membrane under the same conditions.
基金Project(51104186)supported by the National Natural Science Foundation of ChinaProjects(2016zzts282,2016zzts283)supported by the Fundamental Research Funds for the Central Universities of Central South University,China
文摘To extract molybdenum and nickel from the roasted Ni-Mo ore, a process of hydrochloric acid leaching, sulphation roasting and water leaching was investigated. The results showed that this process could get a high leaching rate of Mo and Ni. Under the optimum conditions of hydrochloric acid leaching (roasted Ni-Mo ore leached with 0.219 mL/g hydrochloric acid addition at 65 ℃ for 30 min with a L/S ratio of 3 mL/g), sulphation roasting (51.9% sulfiaric acid addition, roasting temperature 240 ℃ for 1 h), followed by leaching with the first stage hydrochloric acid leaching solution at 95 ℃ for 2 h, the leaching rates of Mo and Ni reached 95.8% and 91.3%, respectively.
文摘Locating the mineral processing plant near a mine is the most important parameter that affects the whole process.Many factors,and their preferences,should be considered in this stage.The factors include economical,geological,technical,environmental and tectonic parameters.A multi-criteria decision making method is necessary to rank the alternatives.In this paper we describe how plant location is selected by using the Analytic Hierarchy Process(AHP).This method,with eight criteria,was used to select a location for the mineral processing plant at the Sangan iron ore mine(phase 1).Three alternatives for the processing plant were evaluated.The main criteria were distance from the mine,access to heavy machinery transport,the amount of excavation required for grading,bed mixture capacity,belt conveyor length,distance from the tailing dam,distance from the waste dumps and surface water diversion requirements.Finally,the alternatives were ranked and the best location was proposed.
文摘The Gejiu (个旧) deposit is a superlarge tin-copper polymetallic ore-forming concentration area characterized by excellent metallogenic geological settings and advantageous ore-controlling factors. The deposit displays diverse mineralization properties due to different minerals and mineral deposit types. Based on the principal metallogenic factors, metallogenic mechanisms, mineralized components, and occurrence of mineral deposits or ore bodies, the Gejiu mineral district can be divided into 2 combinations of metallogenic series, 4 metallogenic series, 8 subseries, and 27 mineral deposit types. Spatial zonality is evident. The distribution regularity of the elements in both plane and section is Be-W, Sn (Cu, Mo, Bi, Be)-Sn, Pb, Ag-Pb, Zn around a granitic intrusion. The metallogenic epoch is mainly concentrated in the late Yanshanian. During this period, large-scale metallogenic processes related to movement caused by tectonics and magmatism occurred, and a series of magmatic hydrothermal deposits formed. The ore-forming processes can be divided into 4 stages: the silicate stage, the oxide stage, the sulphide stage, and the carbonate stage. Based on the orderliness and diversity (in terms of time, space, and genesis) of the mineralization, the authors have developed a comprehensive spectrum of ore deposits in the Gejiu area. This newly proposed diversity of mineralization and the spectrum developed in this work are useful not only for interpreting the genesis of the Gejiu deposit but also for improving mineral exploration in the area, and in particular, for finding large deposits.
基金financially supported by the National Natural Science Foundation of China(No.51304076)the Natural Science Foundation of Hunan Province,China(No.14JJ4064)
文摘Mineral dissemination and pore space distribution in ore particles are important features that influence heap leaching performance. To quantify the mineral dissemination and pore space distribution of an ore particle, a cylindrical copper oxide ore sample (I center dot 4.6 mm x 5.6 mm) was scanned using high-resolution X-ray computed tomography (HRXCT), a nondestructive imaging technology, at a spatial resolution of 4.85 mu m. Combined with three-dimensional (3D) image analysis techniques, the main mineral phases and pore space were segmented and the volume fraction of each phase was calculated. In addition, the mass fraction of each mineral phase was estimated and the result was validated with that obtained using traditional techniques. Furthermore, the pore phase features, including the pore size distribution, pore surface area, pore fractal dimension, pore centerline, and the pore connectivity, were investigated quantitatively. The pore space analysis results indicate that the pore size distribution closely fits a log-normal distribution and that the pore space morphology is complicated, with a large surface area and low connectivity. This study demonstrates that the combination of HRXCT and 3D image analysis is an effective tool for acquiring 3D mineralogical and pore structural data.
文摘The characteristics of aerosol flotation, which include the effect of the concentration and particle size of kerosene aerosol on the molybdenum (Mo) flotation index and the effect of kerosene aerosol dosing method on the kerosene dosage and flotation time, were studied in the flotation of low-grade refractory molybdenum ores using kerosene aerosol. The results revealed that the particle size and concentration of kerosene aerosol had little effect on the Mo grade but had significant effect on the Mo recovery. A smaller particle size and a lower con-centration of kerosene aerosol were beneficial to the Mo aerosol flotation. For the received Mo ore samples, the optimized particle size of kerosene aerosol was 0.3-2 μm and the optimized aerosol concentration was 14 mg/L. The compressed air atomizer had a more uniform dis-tribution of aerosol particles than the ultrasonic atomizer, and the aerosol concentration was controlled easily, so the compressed air atomizer was more suitable for the research of aerosol flotation. Compared with conventional flotation in which kerosene was directly added into the ore pulp, the flotation time was reduced by ~30%, and the dosage was decreased by ~20% in aerosol flotation, while the Mo flotation index was similar.
基金supported by the National Natural Science Foundation of China(Nos.49773195 and 49502029)the Visiting Scholar Foundation of Labs in Universities,Research Foundation of the State Key Laboratory of Metallogenesis in Nanjing University+1 种基金Research Foundation of Youth Teachers of National Educational Department and the Training Program of Medium-youth Teachers supported by the Lingnan Foundationsupported by the“Trans-century Training Programme Foundation for the Talents”by the Ministry of Education.
文摘The newly discovered Changkeng Au-Ag deposit is a new type of sediment-hostedprecious metal deposit. Most of the previous researchers believed that the deposit was formed bymeteoric water convection. By using a high vacuum quadrupole gas mass spectrometric system, ninelight hydrocarbons have been recognized in the fluid inclusions in ore minerals collected from theChangkeng deposit. The hydrocarbons are composed mainly of saturated alkanes C_(1-4) and unsaturatedalkenes C_(2-4) and aromatic hydrocarbons, in which the alkanes are predominant, while the contentsof alkenes and aromatic hydrocarbons are very low. The sum alka/sum alke ratio of most samples ishigher than 100, suggesting that those hydrocarbons are mainly generated by pyrolysis of kerogens insedimentary rocks caused by water-rock interactions at medium-low temperatures, and themetallogenic processes might have not been affected by magmatic activity. A thermodynamiccalculation shows that the light hydrocarbons have reached chemical equilibrium at temperatureshigher than 200 deg C, and they may have been generated in the deep part of sedimentary basins(e.g., the Sanzhou basin) and then be transported by ore-forming fluids to a shallow position of thebasin via a long distance. Most of the organic gases are generated by pyrolysis of the type IIkerogens (kukersite) in sedimentary host rocks, only a few by microorganism activity. Thecompositions and various parameters of light hydrocarbons in gold ores are quite similar to those insilver ores, suggesting that the gold and silver ores may have similar metallogenic processes.Based on the compositions of organic gases in fluid inclusions, the authors infer that the Changkengdeposit may be of a tectonic setting of continental rift. The results of this study support fromone aspect the authors' opinion that the Changkeng deposit is not formed by meteoric waterconvection, and that its genesis has a close relationship with the evolution of the Sanzhou basin,so it belongs to the sedimentary hot brine transformed deposit.
基金supported by the Science Foundation for Outstanding Young Scholars (41822304)the Zhejiang Provincial Natural Science Foundation (LZ16D060001)。
文摘The Piaotang deposit is one of the largest vein-type W-polymetallic deposits in southern Jiangxi Province,South China.The coexistence of wolframite and cassiterite is an important feature of the deposit.Based on detailed petrographic observations,microthermometry of fluid inclusions in wolframite,cassiterite and intergrown quartz was undertaken.The inclusions in wolframite were observed by infrared microscope,while those in cassiterite and quartz were observed in visible light.The fluid inclusions in wolframite can be divided into two types:aqueous inclusions with a large vapor-phase proportion and aqueous inclusions with a small vapor-phase ratio.The homogenization temperature(Th)of inclusions in wolframite with large vapor-phase ratios ranged from 280℃ to 390℃,with salinity ranging from 3.1 to 7.2 wt%NaCl eq.In contrast,the Th values of inclusions with small vapor-phase ratios ranged from 216℃ to 264℃,with salinity values ranging from 3.5 to 9.3 wt%NaCl eq.T_(h) values of primary inclusions in cassiterite ranged from 316℃ to 380℃,with salinity ranging from 5.4 to 9.3 wt%NaCl eq.T_(h) values for primary fluid inclusions in quartz ranged from 162℃ to 309℃,with salinity values ranging from 1.2 to 6.7 wt%NaCl eq.The results show that the formation conditions of wolframite,cassiterite and intergrown quartz are not uniform.The evolutionary processes of fluids related to these three kinds of minerals are also significantly different.Intergrown quartz cannot provide the depositional conditions of wolframite and cassiterite.The fluids related to tungsten mineralization for the NaCl-H_(2)O system had a medium-to-high temperature and low salinity,while the fluids related to tin mineralization for the NaCl-H_(2)O system had a high temperature and medium-to-low salinity.The results of this study suggest that fluid cooling is the main mechanism for the precipitation of tungsten and tin.
基金Project(U1608254) supported by the Special Fund for the National Natural Science Foundation of ChinaProjects(ZJKY2017(B)KFJJ01,ZJKY2017(B)KFJJ02) supported by Zijin Mining Group Co.,Ltd.,China
文摘The effect of temperature on leaching behavior of copper minerals with different occurrence states in complex copper oxide ores was carried out by phase analysis means of XRD, optical microscopy and SEM-EDS. The results indicated that at ambient temperature, the easily leached copper oxide minerals were completely dissolved, while the bonded copper minerals were insoluble. At lukewarm temperature of 40℃, it was mainly the dissolution of copper in isomorphism state. With increasing temperature to 60℃, the copper leaching rate in the adsorbed state was significantly accelerated. In addition, when the temperature increased to 80℃, the isomorphic copper was completely leached, leaving 11.2% adsorbed copper un-leached. However, the copper in feldspar-quartz-copper-iron colloid state was not dissolved throughout the leaching process. Overall, the leaching rates of copper in different copper minerals decreased in the order: malachite, pseudo-malachite > chrysocolla > copper-bearing chlorite > copper-bearing muscovite > copper-bearing biotite > copper-bearing limonite > feldspar-quartz-copper-iron colloid.
基金jointly funded by the national key research and development program project“Strategic Mineral Information and Metallogenic Regularity of the Tethyan Metallogenic Domain”(2021YFC2901803)a project of the National Natural Science Foundation of China entitled“Geological Structure Mapping and Regional Comparative Study of the Tethyan Tectonic Domain”(92055314),International Geoscience Programme(IGCP-741)a project initiated by the China Geological Survey(DD20221910).
文摘The porphyry copper belt in the Geza island arc in southwestern China is the only Indosinian porphyry copper metallogenic belt that has been discovered and evaluated so far.The Pulang porphyry copper deposit(also referred to as the Pulang deposit)in this area has proven copper reserves of 5.11×106 t.This deposit has been exploited on a large scale using advanced mining methods,exhibiting substantial economic benefit.Based on many research results of previous researchers and the authors’team,this study proposed the following key insights.(1)The Geza island arc was once regarded as an immature island arc with only andesites and quartz diorite porphyrites occurring.This understanding was overturned in this study.Acidic endmember components such as quartz monzonite porphyries and quartz monzonite porphyries have been identified in the Geza island arc,and the mineralization is mainly related to the magmatism of quartz monzonite porphyries.(2)Complete porphyry orebodies and large vein orebodies have developed in the Pulang deposit.Main orebody KT1 occurs in the transition area between the potassium silicate alteration zone of quartz monzonite porphyries and the sericite-quartz alteration zone.Most of them have developed in the potassium silicate alteration zone.The main orebody occurs as large lenses at the top of the hanging wall of rock bodies,with an engineering-controlled length of 1920 m and thickness of 32.5‒630.29 m(average:187.07 m).It has a copper grade of 0.21%-1.56%(average:0.42%)and proven copper resources of 5.11×10^(6) t,which are associated with 113 t of gold,1459 t of silver,and 170×10^(3) t of molybdenum.(3)Many studies on diagenetic and metallogenic chronology,isotopes,and fluid inclusions have been carried out for the Pulang deposit,including K-Ar/Ar-Ar dating of monominerals(e.g.,potassium feldspars,biotites,and amphiboles),zircon U-Pb dating,and molybdenite Re-Os dating.The results show that the porphyries in the Pulang deposit are composite plutons and can be classified into pre-mineralization quartz diorite porphyrites,quartz monzonite porphyries formed during the mineralization,and post-mineralization granite porphyries,which were formed at 223±3.7 Ma,218±4 Ma,and 207±3.9 Ma,respectively.The metallogenic age of the Pulang deposit is 213‒216 Ma.(4)The petrogeochemical characteristics show that the Pulang deposit has the characteristics of volcanic arc granites.The calculation results of trace element contents in zircons show that quartz monzonite porphyries and granite porphyries have higher oxygen fugacity.The isotopic tracing results show that the diagenetic and metallogenic materials were derived from mixed crust-and mantle-derived magmas.
基金financial support from the National Natural Science Foundation of China (Nos. 50921002 and 51174203)
文摘Because of the low grade, high oxidation rate and the accumulation of little associated metal sulfide ore in the molybdenum concentrate during flotation, the Qingyang molybdenum ore is difficult to beneficiate. The experimental studies of grinding fineness, the amount of roughing modifier, depressant and collector were completed. In the cleaning process, the contrast experiments of one regrinding, the regrinding and scrubbing, two-stage regrinding was carried. The result shows that the grade of molybdenum ore concentrate is 45.31%, the recovery is 65.98% and the rich ore ratio reaches 20.59% by the regrinding and scrubbing seven cleaning, the regrinding of concentrations from middling of molybdenum-sulfur separation. The regularly-concentrated material from the apparatus was as the middling products. Hence, ideal beneficiation index can be obtained with a rational mineral processing, which offers new beneficiating technology for the refractory low-grade molybdenum ore in China.