The Yangla Cu skarn deposit is located in the central part of the Jinshajiang Suture Zone,southwest China,with a total reserve of 150 Mt Cu@1.03%.The newly discovered antimony orebodies at the depth of Yangla are stri...The Yangla Cu skarn deposit is located in the central part of the Jinshajiang Suture Zone,southwest China,with a total reserve of 150 Mt Cu@1.03%.The newly discovered antimony orebodies at the depth of Yangla are strictly controlled by the stratum,structure,and lithology,which are lenticular and vein-like within the marble fracture zone,which can provide a window into multistage miner-alization and ore genesis at Yangla.Mineralization can be divided into three types,Cu–Pb–Zn(skarn)pyrite,galena,and sphalerite,Cu(porphyry)chalcopyrite and pyrite,and Sb(hydrothermal)stibnite and pyrite.The mineral assem-blages were stibnite+pyrite+calcite+quartz±minor scheelite in antimony ores.This study presents quantitative measurements of the trace element compositions of pyrite and stibnite from the Yangla antimony ores.Analysis of pyrite with electron probe microanalysis(EPMA)showed enrichment in Co,Ni,Sb,As,and Mo,and deficit in its S and Fe contents when compared to the stoichiometric con-centrations of S and Fe in pyrite.The Sb-related pyrite may belong to sedimentary-reworked genesis and may be modi-fied by hydrothermalfluids,thereby presenting a certain dif-ference(i.e.,crystal morphology,texture,and chemical com-position)compared to the skarn and porphyry Cu-related pyrite in the Yangla Cu skarn deposit.Analysis of stibnite with EPMA and inductively coupled plasma-mass spectrom-etry showed enrichment in As,Pb,Sn,Pb,Cu,and Zn,and presented much higher Sb contents and slightly lower S con-tents when compared to the stoichiometric concentrations of Sb and S in stibnite.Statistical analysis of the stibnite trace elements showed correlations for the elemental pairs Cu–Pb,As–Sb,and Sn–Pb,and the coupled substitution equations Sb^(3+)↔Cu^(+)+Pb^(2+),Sb^(3+)↔As^(3+),and Sn^(2+)↔Pb^(2+)may be the major factors governed the incorporating Cu,Pb,As and Sn within the stibnite.Moreover,this study preliminary shows that the antimony mineralization may belong to a car-bonate replacement hydrothermal genesis at Yangla.展开更多
The Dachang superlarge Sn-polymetal deposit in Guangxi, China, is one of the largest tin deposit all over the world. However, this deposit has long been in debate as to its origin. One of the opinions is that the Dach...The Dachang superlarge Sn-polymetal deposit in Guangxi, China, is one of the largest tin deposit all over the world. However, this deposit has long been in debate as to its origin. One of the opinions is that the Dachang deposit was formed by replacement of hydrothermal solution originating from Yanshanian granites, and the other is that this deposit was formed by submarine exhalation in the Devonian. This paper presents some new isotopic geochronology data obtained with the 40Ar-39Ar method for quartz and sanidine from massive ore in the No. 91 and No. 100 orebodies. Analytic results show that the No. 91 orebody was formed at 94.52±0.33 Ma (the plateau age obtained with the 40Ar-39Ar method for quartz) or 91.4±2.9 Ma (the plateau age obtained with the 40Ar-39Ar method for feldspar), while the No. 100 orebody was formed at 94.56±0.45 Ma (the plateau age obtained with the 40Ar-39Ar method for quartz), suggesting that both the No. 91 and the No. 100 orebodies were formed at the Late Yanshanian instead of the Devonian. The No. 100 orebody might be formed by filling of ore materials into caves in Devonian reef limestone. Because the ore-bearing solution released its pressure and lowered its temperature suddenly in a cave environment, ore minerals were formed concentratedly while water and other materials such as CO2 evaporated quickly, resulting less alteration of host rocks.展开更多
The Yulong supper\|large copper deposit is situated within the well\|known S\|N striking Yulong copper\|molybdenum ore belt. The ore\|bearing biotite\|monogranitic porphyry was emplaced within clastic rocks (mainly sh...The Yulong supper\|large copper deposit is situated within the well\|known S\|N striking Yulong copper\|molybdenum ore belt. The ore\|bearing biotite\|monogranitic porphyry was emplaced within clastic rocks (mainly shales and siltstones) of the Jiapila Formation (T 3 j ) and carbonate rocks of the Bolila Formation (T 3 b ) of the Upper Triassic. Five mineralization patterns have been recognized in the deposit, i.e., ①veinlet\|disseminated Cu\|Mo ore in the porphyry; ②skarn\|type Cu ore at the contact zone with carbonates (T 3 b ); ③stratiform\|like oxidized Cu ore between T 3 b carbonate rocks and T 3 j hornstones; ④brecciated Cu ore at the local periphery of porphyry; and ⑤vein Pb\|Zn\|Ag ore in the outer contact zone. They constitute a unique integrated polymetal mineralization series of epigenetic intermediate\|acid magmatic hydrothermal system.Studies have shown that the Yulong deposit was the coupling product of sedimentation, magmatism, and tectonism. The Cu\|bearing sandstones in the Japila Formation have provided partial ore\|bearing materials for the porphyry mineralization during the Himalayan period. The mineralized porphyry mass was passively emplaced and controlled by a nose\|like anticlinal trap opening to the north. The interlayered fractured zone formed during folding between the Jiapila and Bolila Formations acted as favorable host space for stratiform\|like skarn and oxidized ores. A large number of cleavages and fissures developed during folding provided both conduits for the circulation of ore\|forming fluids and host spaces for Pb\|Zn\|Ag ore veins. The veinlet\|disseminated Cu\|Mo ore in the porphyry mass owns the characteristics of typical porphyry copper deposits in the world. The veinlet\|disseminated ore body and the stratiform\|like skarn\|type and/or oxidized ore body, the two main ore bodies in Yulong, are connected with each other and shown as “mushroom\|like" shape, in which the former occurs as “mushroom stem" and the latter as “mushroom cover".展开更多
By means of multivariance analysis and finite element on the basis of the analysis of generation andevolution of structural systems and structural system of syn-metallogenesis in the orefield,the authorsmade a researc...By means of multivariance analysis and finite element on the basis of the analysis of generation andevolution of structural systems and structural system of syn-metallogenesis in the orefield,the authorsmade a research into the interrelation between tecto-geochemistry and structural stress field,revealedthe mechanism of metallogenesis by magma and ore-forming fluids driven under dynamic forces,andproposed a tecto-geochemistry model for the formation of the ore deposits,so as to suggest a basis oftheory for the prognoses of location and magnitude of hidden deposits.展开更多
Abundant organic inclusions are present in the Qinglong antimony deposit. However, the source rocks of these organic matters have not been reliably identified. Recently, a paleo--oil reservoir was found in the Qinglon...Abundant organic inclusions are present in the Qinglong antimony deposit. However, the source rocks of these organic matters have not been reliably identified. Recently, a paleo--oil reservoir was found in the Qinglong antimony deposit. In view of similar components of gaseous hydrocarbon, we propose that the organic matters observed in inclusions in Qinglong antimony deposit would come from this paleo-oil reservoir. We used the Re-Os dating method to determine the age of the bitumen from this paleo-oil reservoir, and obtained an isochron age of 254.3~2.8 Ma. The age indicates that the oil- generation from source rock occurred in the early Late Permian, earlier than the Sb mineralization age (-148~8.5 Ma) in the Qinglong antimony deposit area. After oil generation from Devonian source rock, first and secondary migration, the crude oil have probably entered into the fractures and pores of volcanic rocks and limestone and formed a paleo-oil reservoir in the western wing of Dachang anticline. As burial process deepened, the crude oil has turned into natural gas, migrates into the core of Dachang anticline and formed a paleo-gas reservoir. The hydrocarbons (including CH4) in the reservoirs can serve as reducing agent to provide the sulfur required for Sb mineralization through thermal chemical reduction of sulfates. Therefore, the formation of oil-gas in the area is a prerequisite for the Sb mineralization in the Qinglong antimony deposit.展开更多
The Muli antimony deposit is located in the Au-Sb polymetallic metallogenic belt in south-eastern Yunnan,China.In this paper,we investigated the concentrations of trace elements in gangue minerals,mainly calcite,quart...The Muli antimony deposit is located in the Au-Sb polymetallic metallogenic belt in south-eastern Yunnan,China.In this paper,we investigated the concentrations of trace elements in gangue minerals,mainly calcite,quartz,and pyrite,which were formed at different metallogenic stages.Meanwhile,the host rocks,predominantly composed of limestone,are also analysed for comparison.The calcite from the Nadan ore section is enriched with medium-heavy rare earth elements(M-HREEs),likely due to the presence of a high concentration of Fe and Mn impurities,which results in the preferential enrichment of M-HREEs in the calcite.Alternatively,the calcite may be precipitated from the M-HREE・rich granitic leaching fluid.In the Muli ore section,both quartz and pyrite in the metallogenic period show enrichment with light rare earth elements(LREEs),and the wall rock is also enriched with LREEs,which indicates that the wall rock material was involved in the metallogenic process.The W-shaped tetrad effect of quartz in the late metallogenic stage was interpreted to determine extensive flu id-rock interactions in highly fractionated Si-rich systems.Fe and Mn impurities cause M-HREE to be preferentially enriched with calcite to some extent.Whether mineralization is related to granite deserves further study.Eu and Ce anomalies of different types of gangue minerals indicate that the temperature and the fO2 were constantly changing during mineralization,and the temperature of the main ore-stage was higher than 200°C in an oxidized state.The various REE patterns,LREE/HREE and(La/Yb)N values,reveal that there may be multi-sources and multi-stage hydrothermal activities in the Muli antimony deposit.The REE distribution patterns of minerals are likely interfered with by many internal and external factors.Studies on REE characteristics of calcite,quartz,pyrite and limestone in the Muli antimony deposit have greatly improved the understanding of ore-forming fluids.When we traced the origin and evolution of ore・forming fluids by means of mineral REE distribution patterns,in addition to the determination of inclusions of ore minerals related to mineralization and the in situ analysis methods performed by LA-ICP-MS,we should also com・bine the REE characteristics of various minerals or trace the ore-forming fluids with multiple methods.展开更多
Organic geochemistry and comparisons of characteristics of the organic matter in wall rocks of the ore\|controlling strata and ores of the Lower Jurassic Songling black shale formation and the related Songxi silver\|a...Organic geochemistry and comparisons of characteristics of the organic matter in wall rocks of the ore\|controlling strata and ores of the Lower Jurassic Songling black shale formation and the related Songxi silver\|antimony deposit of northeastern Guangdong have been studied in this paper. The results show that the Lower Jurassic Songling shale formation is a suite of biologic\|rich and organic\|rich ore\|bearing marine sedimentary rocks. Micro\|components of the organic matter in the Songling black shale formation consists primarily of algae, amorphous marine kerogen, solid bitumen, and pyrobitumen. The thermal evolution of organic matter is at the over\|maturity stage. There is a general positive correlation between total organic carbon (TOC) and metallogenetic elements such as Ag and Sb in the black shale formation. Organic matter in the host rocks in the Songxi ore deposit played a role in controlling the silver\|antimony depositing environment during the forming process of the black shale ore\|bearing formation. In the absence of vitrinite, the relative level of thermal maturity calculated by solid bitumen reflectance indicates that the ore\|forming temperature of the Songxi silver\|antimony deposit was about 150-170℃, which was considered as an epithermally reworked ore deposit. The roles of organic matter in the formation of the Songxi ore deposit are a primitive accumulation of the metallogenetic elements (Ag, Sb) in the sea\|water cycle system for ore source and a concentration of metals by ion exchange or chelation as well as reduction of the oxidized metals.展开更多
The Bianbianshan deposit, the unique gold-polymetal (Au-Ag-Cu-Pb-Zn) veined deposit of the polymetal metallogenic belt of the southern segment of Da Hinggan Mountains mineral province, is located at the southern par...The Bianbianshan deposit, the unique gold-polymetal (Au-Ag-Cu-Pb-Zn) veined deposit of the polymetal metallogenic belt of the southern segment of Da Hinggan Mountains mineral province, is located at the southern part of the Hercynian fold belt of the south segment of Da Hinggan Mountains mineral province, NE China. Ores at the Bianbianshan deposit occur within Cretaceous andesite and rhyolite in the form of gold-bearing quartz veins and veinlet groups containing native gold, electrum, pyrite, chalcopyrite, galena and sphalerite. The deposit is hosted by structurally controlled faults associated with intense hydrothermal alteration. The typical alteration assemblage is sericite + chlorite + calcite + quartz, with an inner pyrite-sericite-quartz zone and an outer seicite - chlorite - calcite-epidote zone between orebodies and wall rocks. δ34 S values of 17 sulfides from ores changing from -1.67 to +0.49‰ with average of -0.49‰, are similar to δ34 S values of magmatic or igneous sulfide sulfur. 206Pb/204Pb, 207Pb/204Pb and 208Pb/ 204Pb data of sulfide from ores range within 17.66-17.75, 15.50-15.60, and 37.64-38.00, respectively. These sulfur and lead isotope compositions imply that ore-forming materials might mainly originate from deep sources. H and O isotope study of quartz from ore-bearing veins indicate a mixed source of deep-seated magmatic water and shallower meteoric water. The ore formations resulted from a combination of hydrothermal fluid mixing and a structural setting favoring gold-polymetal deposition. Fluid mixing was possibly the key factor resulting in Au-Ag-Cu-Pb-Zn deposition in the deposit. The metallogenesis of the Bianbianshan deposit may have a relationship with the Cretaceous volcanic-subvolcanic magmatic activity, and formed during the late stage of the crust thinning of North China.展开更多
Antimony doped tin oxide(ATO) thin films have been prepared by pulsed laser deposition(PLD) method.The intrinsic effect of Sb dopant,including the Sb content,transition degree between Sb(3+) and Sb(5+) and c...Antimony doped tin oxide(ATO) thin films have been prepared by pulsed laser deposition(PLD) method.The intrinsic effect of Sb dopant,including the Sb content,transition degree between Sb(3+) and Sb(5+) and crystallinity on the electrical and optical properties of the ATO thin films is mainly investigated.It is suggested that the transition degree of Sb(3+) towards Sb(5+)(Sb(5+)/Sb(3+) ratio) is determined by Sb content.When the Sb content is increased to 12 at%,the Sb(5+)/Sb(3+) ratio reaches the highest value of 2.05,corresponding to the resistivity of 2.70×10(-3) Ω·cm.Meanwhile,the Burstein-Moss effect caused by the increase of carrier concentration is observed and the band gap of the ATO thin films is broadened to 4.0 eV when the Sb content is increased to 12 at%,corresponding to the highest average optical transmittance of 92%.Comprehensively considering the combination of electrical and optical properties,the ATO thin films deposited with Sb content of 12 at%exhibit the best properties with the highest "figure of merit" of 3.85×10(-3) Ω(-1).Finally,an antimony selenide(Sb_2Se_3) heterojunction solar cell prototype with the ATO thin film as the anode has been prepared,and a power conversion efficiency of 0.83%has been achieved.展开更多
Optical studies, backscattered electron images, secondary ion spectrometry and highprecision transmission electron imaging demonstrate that gold is strongly correlated with arsenic on a microscopic scale in the sedime...Optical studies, backscattered electron images, secondary ion spectrometry and highprecision transmission electron imaging demonstrate that gold is strongly correlated with arsenic on a microscopic scale in the sediment-hosted micro-disseminated gold deposits. The positive correlation between Au and As, despite varying Au/As ratio, is persistent in arsenian pyrite overgrowths and arsenopyrite. It is found that gold occurs in native state as submicro beads in association with arsenic-bearing sulfides. The extremely small grain size of gold may indicate a very rapid process of deposition.展开更多
Large areas of old basements of metamorphic volcanic series, and magmatic and sedimentary rocks of different ages existing in China. China is rich in Mesozoic granite rocks which are closely related to nonferrous meta...Large areas of old basements of metamorphic volcanic series, and magmatic and sedimentary rocks of different ages existing in China. China is rich in Mesozoic granite rocks which are closely related to nonferrous metals ore deposits, and favourable for the formation of tungsten, titanium, rare earths and antimony ore deposits. The article identifies the major types and locations of these mineral resources from a geological point of view.展开更多
We report on the fabrication and characterization of multi-leg bismuth telluride (Bi2Te3) and antimony telluride (Sb2Te3) thermoelectric devices. The two materials were deposited, on top of SiO2/Si substrates, using P...We report on the fabrication and characterization of multi-leg bismuth telluride (Bi2Te3) and antimony telluride (Sb2Te3) thermoelectric devices. The two materials were deposited, on top of SiO2/Si substrates, using Pulsed Laser Deposition (PLD). The SiO2 layer was used to provide insulation between the devices and the Si wafer. Copper was used as an electrical connector and a contact for the junctions. Four devices were built, where the Bi2Te3 and Sb2Te3 were deposited at substrate temperatures of 100°C, 200°C, 300°C and 400°C. The results show that the device has a voltage sensitivity of up to 146 μV/K and temperature sensitivity of 6.8 K/mV.展开更多
基金This research was funded by the National Natural Science Foundation of China(No.41862007)the Key Disciplines Construction of Kunming University of Science and Technology(No.14078384)the Yunnan Ten Thousand Talents Plan Young&Elite Talents Project(YNWR-QNBJ-2018-093)。
文摘The Yangla Cu skarn deposit is located in the central part of the Jinshajiang Suture Zone,southwest China,with a total reserve of 150 Mt Cu@1.03%.The newly discovered antimony orebodies at the depth of Yangla are strictly controlled by the stratum,structure,and lithology,which are lenticular and vein-like within the marble fracture zone,which can provide a window into multistage miner-alization and ore genesis at Yangla.Mineralization can be divided into three types,Cu–Pb–Zn(skarn)pyrite,galena,and sphalerite,Cu(porphyry)chalcopyrite and pyrite,and Sb(hydrothermal)stibnite and pyrite.The mineral assem-blages were stibnite+pyrite+calcite+quartz±minor scheelite in antimony ores.This study presents quantitative measurements of the trace element compositions of pyrite and stibnite from the Yangla antimony ores.Analysis of pyrite with electron probe microanalysis(EPMA)showed enrichment in Co,Ni,Sb,As,and Mo,and deficit in its S and Fe contents when compared to the stoichiometric con-centrations of S and Fe in pyrite.The Sb-related pyrite may belong to sedimentary-reworked genesis and may be modi-fied by hydrothermalfluids,thereby presenting a certain dif-ference(i.e.,crystal morphology,texture,and chemical com-position)compared to the skarn and porphyry Cu-related pyrite in the Yangla Cu skarn deposit.Analysis of stibnite with EPMA and inductively coupled plasma-mass spectrom-etry showed enrichment in As,Pb,Sn,Pb,Cu,and Zn,and presented much higher Sb contents and slightly lower S con-tents when compared to the stoichiometric concentrations of Sb and S in stibnite.Statistical analysis of the stibnite trace elements showed correlations for the elemental pairs Cu–Pb,As–Sb,and Sn–Pb,and the coupled substitution equations Sb^(3+)↔Cu^(+)+Pb^(2+),Sb^(3+)↔As^(3+),and Sn^(2+)↔Pb^(2+)may be the major factors governed the incorporating Cu,Pb,As and Sn within the stibnite.Moreover,this study preliminary shows that the antimony mineralization may belong to a car-bonate replacement hydrothermal genesis at Yangla.
基金the State Key BasicResearch Program ofChina(TG1999043203 ,TG1999043201) the Geological Survey Program(K1.4-3-4)under the Ministry of Land and Resources.
文摘The Dachang superlarge Sn-polymetal deposit in Guangxi, China, is one of the largest tin deposit all over the world. However, this deposit has long been in debate as to its origin. One of the opinions is that the Dachang deposit was formed by replacement of hydrothermal solution originating from Yanshanian granites, and the other is that this deposit was formed by submarine exhalation in the Devonian. This paper presents some new isotopic geochronology data obtained with the 40Ar-39Ar method for quartz and sanidine from massive ore in the No. 91 and No. 100 orebodies. Analytic results show that the No. 91 orebody was formed at 94.52±0.33 Ma (the plateau age obtained with the 40Ar-39Ar method for quartz) or 91.4±2.9 Ma (the plateau age obtained with the 40Ar-39Ar method for feldspar), while the No. 100 orebody was formed at 94.56±0.45 Ma (the plateau age obtained with the 40Ar-39Ar method for quartz), suggesting that both the No. 91 and the No. 100 orebodies were formed at the Late Yanshanian instead of the Devonian. The No. 100 orebody might be formed by filling of ore materials into caves in Devonian reef limestone. Because the ore-bearing solution released its pressure and lowered its temperature suddenly in a cave environment, ore minerals were formed concentratedly while water and other materials such as CO2 evaporated quickly, resulting less alteration of host rocks.
文摘The Yulong supper\|large copper deposit is situated within the well\|known S\|N striking Yulong copper\|molybdenum ore belt. The ore\|bearing biotite\|monogranitic porphyry was emplaced within clastic rocks (mainly shales and siltstones) of the Jiapila Formation (T 3 j ) and carbonate rocks of the Bolila Formation (T 3 b ) of the Upper Triassic. Five mineralization patterns have been recognized in the deposit, i.e., ①veinlet\|disseminated Cu\|Mo ore in the porphyry; ②skarn\|type Cu ore at the contact zone with carbonates (T 3 b ); ③stratiform\|like oxidized Cu ore between T 3 b carbonate rocks and T 3 j hornstones; ④brecciated Cu ore at the local periphery of porphyry; and ⑤vein Pb\|Zn\|Ag ore in the outer contact zone. They constitute a unique integrated polymetal mineralization series of epigenetic intermediate\|acid magmatic hydrothermal system.Studies have shown that the Yulong deposit was the coupling product of sedimentation, magmatism, and tectonism. The Cu\|bearing sandstones in the Japila Formation have provided partial ore\|bearing materials for the porphyry mineralization during the Himalayan period. The mineralized porphyry mass was passively emplaced and controlled by a nose\|like anticlinal trap opening to the north. The interlayered fractured zone formed during folding between the Jiapila and Bolila Formations acted as favorable host space for stratiform\|like skarn and oxidized ores. A large number of cleavages and fissures developed during folding provided both conduits for the circulation of ore\|forming fluids and host spaces for Pb\|Zn\|Ag ore veins. The veinlet\|disseminated Cu\|Mo ore in the porphyry mass owns the characteristics of typical porphyry copper deposits in the world. The veinlet\|disseminated ore body and the stratiform\|like skarn\|type and/or oxidized ore body, the two main ore bodies in Yulong, are connected with each other and shown as “mushroom\|like" shape, in which the former occurs as “mushroom stem" and the latter as “mushroom cover".
文摘By means of multivariance analysis and finite element on the basis of the analysis of generation andevolution of structural systems and structural system of syn-metallogenesis in the orefield,the authorsmade a research into the interrelation between tecto-geochemistry and structural stress field,revealedthe mechanism of metallogenesis by magma and ore-forming fluids driven under dynamic forces,andproposed a tecto-geochemistry model for the formation of the ore deposits,so as to suggest a basis oftheory for the prognoses of location and magnitude of hidden deposits.
基金financially supported by Natural Science Foundation of China (No.41362007)The Research of Scientific Base of Typical Metal Mineral from the Ministry of Land and Resources (No.20091107)the Research Project on the Metallogenic Regularity of the Typical Strata Controlled Deposits of National Crisis Mines in Southwest China (No.20089943)
文摘Abundant organic inclusions are present in the Qinglong antimony deposit. However, the source rocks of these organic matters have not been reliably identified. Recently, a paleo--oil reservoir was found in the Qinglong antimony deposit. In view of similar components of gaseous hydrocarbon, we propose that the organic matters observed in inclusions in Qinglong antimony deposit would come from this paleo-oil reservoir. We used the Re-Os dating method to determine the age of the bitumen from this paleo-oil reservoir, and obtained an isochron age of 254.3~2.8 Ma. The age indicates that the oil- generation from source rock occurred in the early Late Permian, earlier than the Sb mineralization age (-148~8.5 Ma) in the Qinglong antimony deposit area. After oil generation from Devonian source rock, first and secondary migration, the crude oil have probably entered into the fractures and pores of volcanic rocks and limestone and formed a paleo-oil reservoir in the western wing of Dachang anticline. As burial process deepened, the crude oil has turned into natural gas, migrates into the core of Dachang anticline and formed a paleo-gas reservoir. The hydrocarbons (including CH4) in the reservoirs can serve as reducing agent to provide the sulfur required for Sb mineralization through thermal chemical reduction of sulfates. Therefore, the formation of oil-gas in the area is a prerequisite for the Sb mineralization in the Qinglong antimony deposit.
基金supported by the National Natural Science Foundation of China (Grant Nos. 41772070, 41303038)Open Fund of State Key Laboratory of Ore Deposit Geochemistry (201502)
文摘The Muli antimony deposit is located in the Au-Sb polymetallic metallogenic belt in south-eastern Yunnan,China.In this paper,we investigated the concentrations of trace elements in gangue minerals,mainly calcite,quartz,and pyrite,which were formed at different metallogenic stages.Meanwhile,the host rocks,predominantly composed of limestone,are also analysed for comparison.The calcite from the Nadan ore section is enriched with medium-heavy rare earth elements(M-HREEs),likely due to the presence of a high concentration of Fe and Mn impurities,which results in the preferential enrichment of M-HREEs in the calcite.Alternatively,the calcite may be precipitated from the M-HREE・rich granitic leaching fluid.In the Muli ore section,both quartz and pyrite in the metallogenic period show enrichment with light rare earth elements(LREEs),and the wall rock is also enriched with LREEs,which indicates that the wall rock material was involved in the metallogenic process.The W-shaped tetrad effect of quartz in the late metallogenic stage was interpreted to determine extensive flu id-rock interactions in highly fractionated Si-rich systems.Fe and Mn impurities cause M-HREE to be preferentially enriched with calcite to some extent.Whether mineralization is related to granite deserves further study.Eu and Ce anomalies of different types of gangue minerals indicate that the temperature and the fO2 were constantly changing during mineralization,and the temperature of the main ore-stage was higher than 200°C in an oxidized state.The various REE patterns,LREE/HREE and(La/Yb)N values,reveal that there may be multi-sources and multi-stage hydrothermal activities in the Muli antimony deposit.The REE distribution patterns of minerals are likely interfered with by many internal and external factors.Studies on REE characteristics of calcite,quartz,pyrite and limestone in the Muli antimony deposit have greatly improved the understanding of ore-forming fluids.When we traced the origin and evolution of ore・forming fluids by means of mineral REE distribution patterns,in addition to the determination of inclusions of ore minerals related to mineralization and the in situ analysis methods performed by LA-ICP-MS,we should also com・bine the REE characteristics of various minerals or trace the ore-forming fluids with multiple methods.
基金ThisprojectwasjointlysupportedbytheNationalNaturalScienceFoundationofChina! (No :49872 0 37) theDoctoralProgramFoundationfor
文摘Organic geochemistry and comparisons of characteristics of the organic matter in wall rocks of the ore\|controlling strata and ores of the Lower Jurassic Songling black shale formation and the related Songxi silver\|antimony deposit of northeastern Guangdong have been studied in this paper. The results show that the Lower Jurassic Songling shale formation is a suite of biologic\|rich and organic\|rich ore\|bearing marine sedimentary rocks. Micro\|components of the organic matter in the Songling black shale formation consists primarily of algae, amorphous marine kerogen, solid bitumen, and pyrobitumen. The thermal evolution of organic matter is at the over\|maturity stage. There is a general positive correlation between total organic carbon (TOC) and metallogenetic elements such as Ag and Sb in the black shale formation. Organic matter in the host rocks in the Songxi ore deposit played a role in controlling the silver\|antimony depositing environment during the forming process of the black shale ore\|bearing formation. In the absence of vitrinite, the relative level of thermal maturity calculated by solid bitumen reflectance indicates that the ore\|forming temperature of the Songxi silver\|antimony deposit was about 150-170℃, which was considered as an epithermally reworked ore deposit. The roles of organic matter in the formation of the Songxi ore deposit are a primitive accumulation of the metallogenetic elements (Ag, Sb) in the sea\|water cycle system for ore source and a concentration of metals by ion exchange or chelation as well as reduction of the oxidized metals.
基金financially supported by the National Natural Science Foundation of China (No. 40972065)the Special Project (No. XDA08100500) of the Chinese Academy of Science
文摘The Bianbianshan deposit, the unique gold-polymetal (Au-Ag-Cu-Pb-Zn) veined deposit of the polymetal metallogenic belt of the southern segment of Da Hinggan Mountains mineral province, is located at the southern part of the Hercynian fold belt of the south segment of Da Hinggan Mountains mineral province, NE China. Ores at the Bianbianshan deposit occur within Cretaceous andesite and rhyolite in the form of gold-bearing quartz veins and veinlet groups containing native gold, electrum, pyrite, chalcopyrite, galena and sphalerite. The deposit is hosted by structurally controlled faults associated with intense hydrothermal alteration. The typical alteration assemblage is sericite + chlorite + calcite + quartz, with an inner pyrite-sericite-quartz zone and an outer seicite - chlorite - calcite-epidote zone between orebodies and wall rocks. δ34 S values of 17 sulfides from ores changing from -1.67 to +0.49‰ with average of -0.49‰, are similar to δ34 S values of magmatic or igneous sulfide sulfur. 206Pb/204Pb, 207Pb/204Pb and 208Pb/ 204Pb data of sulfide from ores range within 17.66-17.75, 15.50-15.60, and 37.64-38.00, respectively. These sulfur and lead isotope compositions imply that ore-forming materials might mainly originate from deep sources. H and O isotope study of quartz from ore-bearing veins indicate a mixed source of deep-seated magmatic water and shallower meteoric water. The ore formations resulted from a combination of hydrothermal fluid mixing and a structural setting favoring gold-polymetal deposition. Fluid mixing was possibly the key factor resulting in Au-Ag-Cu-Pb-Zn deposition in the deposit. The metallogenesis of the Bianbianshan deposit may have a relationship with the Cretaceous volcanic-subvolcanic magmatic activity, and formed during the late stage of the crust thinning of North China.
基金Funded by the International Science&Technology Cooperation Program of China(No.2011DFA52650)the"111"Project(No.B13035)+1 种基金the National Natural Science Foundation of China(No.51521001)the Fundamental Research Funds for the Central Universities
文摘Antimony doped tin oxide(ATO) thin films have been prepared by pulsed laser deposition(PLD) method.The intrinsic effect of Sb dopant,including the Sb content,transition degree between Sb(3+) and Sb(5+) and crystallinity on the electrical and optical properties of the ATO thin films is mainly investigated.It is suggested that the transition degree of Sb(3+) towards Sb(5+)(Sb(5+)/Sb(3+) ratio) is determined by Sb content.When the Sb content is increased to 12 at%,the Sb(5+)/Sb(3+) ratio reaches the highest value of 2.05,corresponding to the resistivity of 2.70×10(-3) Ω·cm.Meanwhile,the Burstein-Moss effect caused by the increase of carrier concentration is observed and the band gap of the ATO thin films is broadened to 4.0 eV when the Sb content is increased to 12 at%,corresponding to the highest average optical transmittance of 92%.Comprehensively considering the combination of electrical and optical properties,the ATO thin films deposited with Sb content of 12 at%exhibit the best properties with the highest "figure of merit" of 3.85×10(-3) Ω(-1).Finally,an antimony selenide(Sb_2Se_3) heterojunction solar cell prototype with the ATO thin film as the anode has been prepared,and a power conversion efficiency of 0.83%has been achieved.
文摘Optical studies, backscattered electron images, secondary ion spectrometry and highprecision transmission electron imaging demonstrate that gold is strongly correlated with arsenic on a microscopic scale in the sediment-hosted micro-disseminated gold deposits. The positive correlation between Au and As, despite varying Au/As ratio, is persistent in arsenian pyrite overgrowths and arsenopyrite. It is found that gold occurs in native state as submicro beads in association with arsenic-bearing sulfides. The extremely small grain size of gold may indicate a very rapid process of deposition.
文摘Large areas of old basements of metamorphic volcanic series, and magmatic and sedimentary rocks of different ages existing in China. China is rich in Mesozoic granite rocks which are closely related to nonferrous metals ore deposits, and favourable for the formation of tungsten, titanium, rare earths and antimony ore deposits. The article identifies the major types and locations of these mineral resources from a geological point of view.
文摘We report on the fabrication and characterization of multi-leg bismuth telluride (Bi2Te3) and antimony telluride (Sb2Te3) thermoelectric devices. The two materials were deposited, on top of SiO2/Si substrates, using Pulsed Laser Deposition (PLD). The SiO2 layer was used to provide insulation between the devices and the Si wafer. Copper was used as an electrical connector and a contact for the junctions. Four devices were built, where the Bi2Te3 and Sb2Te3 were deposited at substrate temperatures of 100°C, 200°C, 300°C and 400°C. The results show that the device has a voltage sensitivity of up to 146 μV/K and temperature sensitivity of 6.8 K/mV.