Many important metal resources, such as Ni (Cu, Co), PGE, exist in magmatic sulfide deposits, are a hot spot in geological research. We divide the magmatic sulphide deposits in China into four types according to the...Many important metal resources, such as Ni (Cu, Co), PGE, exist in magmatic sulfide deposits, are a hot spot in geological research. We divide the magmatic sulphide deposits in China into four types according to their tectonic setting, intruding mode, ore deposit mode, main metallogenic elements. The four types are as follows: (1) Small-intrusion deposits in paleo-continent; (2) Smallintrusion deposits in continental flood basalt; (3) Small-intrusion deposits in orogenic belt; and (4) The deposits associated with ophiolites. On the basis of the classification, we put forward that the main magmatic metallogenic type in China is small-intrusion metallogeny, and describe its characteristics from small intrusions related concept, three geologic settings, three volcanic-intrusive assemblages and metallogenic key factors. According to the experiences of prospecting at home and abroad, we point out that there is big potential in prospecting small-intrusion deposits, which need further study. At last, we indicate that small-intrusion metallogeny not only widely distributes in mafic-ultramafic intrusions, but also has an important economic value and scientific significance in intermediate-acid intrusions.展开更多
Ore forming processes involve the redistribution of heat, mass and momentum by a wide range of processes operating at different time and length scales. The fastest process at any given length scale tends to be the dom...Ore forming processes involve the redistribution of heat, mass and momentum by a wide range of processes operating at different time and length scales. The fastest process at any given length scale tends to be the dominant control. Applying this principle to the array of physical processes that operate within magma flow pathways leads to some key insights into the origins of magmatic Ni-Cu-PGE sulfide ore deposits. A high proportion of mineralised systems, including those in the super-giant Noril'sk-Talnakh camp, are formed in small conduit intrusions where assimilation of country rock has played a major role. Evidence of this process is reflected in the common association of sulfides with varitextured contaminated host rocks containing xenoliths in varying stages of assimilation. Direct incorporation of S-bearing country rock xenoliths is likely to be the dominant mechanism for generating sulfide liquids in this setting. However, the processes of melting or dissolving these xenoliths is relatively slow compared with magma flow rates and, depending on xenolith lithology and the composition of the carrier magma, slow compared with settling and accumulation rates. Chemical equilibration between sulfide droplets and silicate magma is slower still, as is the process of dissolving sulfide liquid into initially undersaturated silicate magmas. Much of the transport and deposition of sulfide in the carrier magmas may occur while sulfide is still incorporated in the xenoliths, accounting for the common association of magmatic sulfide-matrix ore breccias and contaminated "taxitic" host rocks. Effective upgrading of so-formed sulfide liquids would require repetitive recycling by processes such as reentrainment, back flow or gravity flow operating over the lifetime of the magma transport system as a whole. In contrast to mafic-hosted systems, komatiite-hosted ores only rarely show an association with externally-derived xenoliths, an observation which is partially due to the predominant formation of ores in lava flows rather than deep-seated intrusions, but also to the much shorter timescales of key component systems in hotter, less viscous magmas. Nonetheless, multiple cycles of deposition and entrainment are necessary to account for the metal contents of komatiite-hosted sulfides. More generally, the time and length scale approach introduced here may be of value in understanding other igneous processes as well as non-magmatic mineral systems.展开更多
REE geochemical characteristics of the magmatic rocks and gold deposits in Shizishan ore-field of Tongling were studied. Three types of the magmatic rocks have almost the same chondrite-normalized REE patterns, Eu and...REE geochemical characteristics of the magmatic rocks and gold deposits in Shizishan ore-field of Tongling were studied. Three types of the magmatic rocks have almost the same chondrite-normalized REE patterns, Eu and Ce anomalous values, and ∑REE, ∑LREE/∑HREE regular changes, which indicates that their magmas come from the same source and their digenetic mechanism is fractional crystallization. In three gold deposits, the mineral ores and related altered rocks have similar chondrite-normalized REE patterns and sharp Eu positive anomalous values. The REE contents reduced from the magmatic rocks to skamization or alteration magmatic rocks, skam type ores, sulphide type ores, wall-rocks limestone or marble. The REE geochemical characteristics of the ores and related rocks show that primary fluids originated from magmatic differentiation in lower pressure of shallow crust, ore-forming hydrothermal solutions gained REE and mineralization elements further from leaching the magmatic rocks, then superimposed and reformed the limestones or marbles and deposited ore-forming material.展开更多
A great number of magmatic Cu-Ni deposits(including Kalatongke in Xinjiang and Hongqiling in Jilin) are distributed over a distance of almost 3000 km across the Tianshan-Xingmeng Orogenic Belt, from Tianshan Mountains...A great number of magmatic Cu-Ni deposits(including Kalatongke in Xinjiang and Hongqiling in Jilin) are distributed over a distance of almost 3000 km across the Tianshan-Xingmeng Orogenic Belt, from Tianshan Mountains in Xinjiang in the west, to Jilin in eastern China in the east. These deposits were formed during a range of magmatic episodes from the Devonian to the Triassic. Significant magmatic Cu-Ni-Co-PGE deposits were formed from the Devonian period in the Nalati arc(e.g. Jingbulake Cu-Ni in Xinjiang), Carboniferous period in the Puerjin-Ertai arc(e.g. Kalatongke Cu-Ni-Co-PGE in Xinjiang), Carboniferous period in the Dananhu-Touquan arc(e.g. Huangshandong, Xiangshan and Tulaergen in estern Tianshan, Xinjiang) to Triassic period in the Hulan arc(e.g. Hongqiling Cu-Ni in Jilin). In addition to the overall tectonic, geologic and distribution of magmatic Cu-Ni deposits in the Tianshan-Xingmeng Orogenic Belt, the metallogenic setting, deposit geology and mineralization characteristics of each deposit mentioned above are summarized in this paper. Geochronologic data of Cu-Ni deposits indicate that, from west to east, the metallogenic ages in the Tianshan-Xingmeng Orogenic Belt changed with time, namely, from the Late Caledonian(~440 Ma), through the Late Hercynian(300-265 Ma) to the Late Indosinian(225-200 Ma). Such variation could reflect a gradual scissor type closure of the paleo Asian ocean between the Siberia Craton and the North China Craton from west to east.展开更多
Deep seated magmatic liquation injection deposits form a major type of magmatic sulfide deposit in China. The reserves of nickel and copper in this type of deposit may attain several hundred thousand tons (e.g.Hongq...Deep seated magmatic liquation injection deposits form a major type of magmatic sulfide deposit in China. The reserves of nickel and copper in this type of deposit may attain several hundred thousand tons (e.g.Hongqi 7 and Karatunggu) to nearly ten million tons (e.g.Jinchuan). Those deposits can be classified as large or superlarge deposits. The ore grade is relatively high, commonly with w (Ni)>1 %. The mineralized intrusions are small in size, generally only 0.0 n km 2 to 0. n km 2, with the largest one not exceeding a few km 2. Before intruding, the primary magmas have undergone liquation and partial crystallization at depth; as a result, the magmas have partitioned into barren magma, ore bearing magma, ore rich magma and ore magma, which then ascended and injected into the present locations once or multiple times, to form ore deposits. The above mentioned mineralizing process is known as deep seated magmatic liquation injection mineralization. The volume of the barren magma is generally much larger than those of the ore bearing magma, ore rich magma and ore magma. In the ascending process, most of the barren magma intruded into different locations or outpoured onto the ground surface, forming intrusions or lava flows. The rest barren magma, ore bearing magma, ore rich magma and ore magma may either multiple times inject into the same place in which rocks and ores are formed or separately inject into different spaces to form rocks and ores. Such deep seated magmatic liquation injection deposits have a much smaller volume, greater ore potential and higher ore grade than those of in situ magmatic liquation deposits. Consequently, this mineralizing process leads to the formation of large deposits in small intrusions.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
The Jinchuan magmatic Ni-Cu deposit,located in the Longshou Mountain region,is the largest producer of Ni and Cu in China,with mineralization being related to mafic and ultramafic magmatism.Previous studies have shown...The Jinchuan magmatic Ni-Cu deposit,located in the Longshou Mountain region,is the largest producer of Ni and Cu in China,with mineralization being related to mafic and ultramafic magmatism.Previous studies have shown that the Longshou Mountain was combined with the Qilian Mountains before Neoproterozoic,and was separated from each other due to the opening of late Qilian oceanic basin in the Paleozoic.The relict Precambrian microcontinents of the Longshou Mountain and Qilian Mountain展开更多
The Habo deposit is a typical porphyry Cu-Mo deposit in the Ailaoshan–Red River metallogenic belt.Ore minerals in the Habo deposit typically occur as veins in the monzonite porphyry.Zircon U-Pb dating suggests that t...The Habo deposit is a typical porphyry Cu-Mo deposit in the Ailaoshan–Red River metallogenic belt.Ore minerals in the Habo deposit typically occur as veins in the monzonite porphyry.Zircon U-Pb dating suggests that the monzonite porphyry formed at 35.07±0.38 Ma.The monzonite porphyry is characterized by high SiO_(2),Al_(2)O_(3),K_(2)O and Na_(2)O contents,with A/CNK ratios ranging from 0.97 to 1.02.All samples exhibit fractionated REE patterns,characterized by high(La/Yb)N ratios(9.4–13.6,average of 11.2).They show adakite-like geochemical features,high Sr concentrations(627–751 ppm,average of 700 ppm),low Y concentrations(15.13–16.86 ppm,average of 15.81 ppm)and high Sr/Y values(39.5–47.4,average of 44.3).These samples have high initial^(87)Sr/^(86)Sr ratios(0.7074–0.7076)and negativeεNd(t)values(-5.1 to-3.7),whereas the zirconεHf(t)values range from-2.2 to+0.4,suggesting that the monzonite porphyry was derived from the partial melting of a thickened juvenile lower crust.The oxygen fugacity,calculated on the basis of the chemical composition of the amphiboles,shows?NNO values ranging from+1.65 to+2.16(average of 1.94)and lg(fO_(2))ranging from-12.72 to-11.99(average of-12.25),indicating that the monzonite porphyry has high oxygen fugacity.Zircons have high Ce^(4+)/Ce^(3+)ratios(29.29–164.24,average of 84.92),with high?FMQ values ranging from+0.50 to+1.51(average of 0.87)and high lg(fO_(2))values ranging from-14.72 to-12.85(average of-14.07),which also indicates that the oxygen fugacity of the magma was high.The dissolved water content of the Habo monzonite porphyry is 9.5–11.5 wt%,according to the geochemical characteristics,zircon-saturation thermometry(692–794°C)and the mineral phases(amphibole,no plagioclase)in the deep magma chamber.Combined with previous studies,we propose that the high oxygen fugacity and high water content of magma played key roles in controlling the formation of the Habo and other Cu-Mo-Au deposits in the Ailaoshan–Red River metallogenic belt.展开更多
Primitive mantle normalized Platinum group elements (PGE) concentration patterns for the Zhengziyanwo intrusion and Dashibao Formation basalts are of positive slope, similar to most of the world class magmatic Ni Cu P...Primitive mantle normalized Platinum group elements (PGE) concentration patterns for the Zhengziyanwo intrusion and Dashibao Formation basalts are of positive slope, similar to most of the world class magmatic Ni Cu PGE sulfide deposits. Characters of this intrusion and its related ores and Dashibao Formation basalts are their negative Pt anomaly and high concentration of Rh relative to Pt and Pd, facts being interpreted to be the results of crystallization and fractionation of Pt alloys and spinel phase free crystallization history for the magma, respectively. PGE parameters of the Dashibao Formation basalts are consistent with the general trend of those found for the Zhengziyanwo intrusion, and this might infer a genetic link between them.展开更多
The Wangershan gold deposit and spatially related Shangzhuang granite, eastern Shandong Province, have been precisely dated by 40 Ar/ 39 Ar laser incremental heating technique. Magmatic hornblende and biotite, ...The Wangershan gold deposit and spatially related Shangzhuang granite, eastern Shandong Province, have been precisely dated by 40 Ar/ 39 Ar laser incremental heating technique. Magmatic hornblende and biotite, collected from the Shangzhuang granites, yielded well-defined and reproducible plateau ages at 128.1-127.5 and 124.4-124.1 Ma (2 σ ), measuring the cooling ages of the intrusion at ca. 500 ℃ and 300-350 ℃, respectively. Hydrothermal sericite extracted from auriferous vein gave high-quality plateau ages between (120.6±0.3) Ma and (120.0±0.4) Ma (2 σ ). Given the similarity of the closure temperature for argon diffusion (300-350 ℃) in the sericite mineral to the homogenization temperature of primary fluid inclusions in the quartz from gold ores, and the intergrowth of sericite with native gold, present 40 Ar/ 39 Ar sericite ages can be reliably interpreted in terms of the mineralization age for the Wangershan deposit. 40 Ar/ 39 Ar hornblende and biotite ages permit an estimate for the cooling rate of the Shangzhuang granite at about 50 ℃/Ma. There are abundant intermediate-mafic dikes in most gold camps of eastern Shandong, whose ages of formation have been previously constrained mainly at 121-119 Ma. The temporal association between the Shangzhuang granite, the Wangershan gold deposit, and the widespread dikes confirms that intrusive activity, gold mineralization, and dike emplacement in this region were broadly coeval, reflecting significant continental lithosphere thinning and resulting crustal extension of Early Cretaceous in eastern China.展开更多
The Wenyu copper polymetallic deposit, with proven reserves of about 0.23 Mt Cu, 394 t Ag and 0.04 Mt Pb, is located in the central part of the Lancangjiang volcanic rock belt (Fig. l a), which is one of the most po...The Wenyu copper polymetallic deposit, with proven reserves of about 0.23 Mt Cu, 394 t Ag and 0.04 Mt Pb, is located in the central part of the Lancangjiang volcanic rock belt (Fig. l a), which is one of the most potential copper polymetallic exploration areas in SW China.展开更多
Rare metal ore reserves are an important strategic resource, and their metallogenic mechanism and mineralization studies have also been received widespread international attention.
In order to study the characteristics of sea-floor exhalative sedimentary and magmatic hydrothermal superimposition on the Bainiuchang polymetallic deposit, the REE compositions of the granites, host-rocks and ores ha...In order to study the characteristics of sea-floor exhalative sedimentary and magmatic hydrothermal superimposition on the Bainiuchang polymetallic deposit, the REE compositions of the granites, host-rocks and ores have been systematically analyzed by ICP-MS. As viewed from their REE compositions, the granites show obvious negative Eu anomalies and weak negative Ce anomalies. According to their REE characteristics, the host-rocks were derived partly from sea-floor exhalative sediments. In terms of their REE compositions, the ores can be divided into two groups: one group, of which the samples were collected from the Baiyang segment relatively far away from the Bozhushan granite batholith, possesses positive Eu anomalies or no Eu anomaly and negative Ce anomalies, indicating that ore-forming hydrothermal fluid was relatively reductive and its temperature was higher than 250 ℃. Furthermore, the coinstantaneous presence of positive Eu anomalies and negative Ce anomalies indicate that the convective mixing of a little amount of seawater with hydrothermal fluid had happened while ores were precipitated on ancient sea floor. The other group, of which the samples were mainly collected from the Chuanxindong and Duimenshan segments near the Bozhushan granite batholith, has similar chondrite-monalized REE distribution patterns to those of the magmatic rocks. But as a whole, the REE characteristics of both groups change gradually starting from the Bozhushan granite batholith. Based on the REE characteristics of the granites, host-rocks and ores, it is suggested that the ore-forming metals seem to have come from several different sources.展开更多
Objective The Sachakou Pb-Zn polymetallic deposit is located in Hetian County, Xinjiang (geographical coordinates of E78° 57' 54.30"-78°59' 53.63", N34° 39' 27.50"-34° 40' 57.21"). It be...Objective The Sachakou Pb-Zn polymetallic deposit is located in Hetian County, Xinjiang (geographical coordinates of E78° 57' 54.30"-78°59' 53.63", N34° 39' 27.50"-34° 40' 57.21"). It belongs to the West Kunlun orogenic belt on the northwest edge of the Qinghai-Tibet Plateau and is connected to the Sanjiang orogenic belt to the south (Spurlin et al., 2005). In recent years, a series of Pb-Zn mineralized spots and deposits have been discovered in this area one after another, which is called the Huoshaoyun ore concentration area. Among them, the Sachakou Pb-Zn deposit has reserves up to140 Mt, which has reached a large scale. However, the study on the genesis of deposits in this area has only just begun. This work studied the genesis ofthis Pb-Zn deposit in order to provide new ideas for the genesis of regional deposits and regional prospecting.展开更多
1 Introduction The uranium deposits related with Indosinian and Yanshanian granite have provided the abundant resource of uranium during the past several decades in China.The deposits are mainly distributing in the Gu...1 Introduction The uranium deposits related with Indosinian and Yanshanian granite have provided the abundant resource of uranium during the past several decades in China.The deposits are mainly distributing in the Guidong granite展开更多
文摘Many important metal resources, such as Ni (Cu, Co), PGE, exist in magmatic sulfide deposits, are a hot spot in geological research. We divide the magmatic sulphide deposits in China into four types according to their tectonic setting, intruding mode, ore deposit mode, main metallogenic elements. The four types are as follows: (1) Small-intrusion deposits in paleo-continent; (2) Smallintrusion deposits in continental flood basalt; (3) Small-intrusion deposits in orogenic belt; and (4) The deposits associated with ophiolites. On the basis of the classification, we put forward that the main magmatic metallogenic type in China is small-intrusion metallogeny, and describe its characteristics from small intrusions related concept, three geologic settings, three volcanic-intrusive assemblages and metallogenic key factors. According to the experiences of prospecting at home and abroad, we point out that there is big potential in prospecting small-intrusion deposits, which need further study. At last, we indicate that small-intrusion metallogeny not only widely distributes in mafic-ultramafic intrusions, but also has an important economic value and scientific significance in intermediate-acid intrusions.
基金The computational fluid dynamic simulations were supported by resources provided by the Pawsey Supercomputing Centre with funding from the Australian Government and the Government of Western AustraliaBoth authors were supported by CSIRO Research Plus (formerly Office of the Chief Executive) internal fellowship funds
文摘Ore forming processes involve the redistribution of heat, mass and momentum by a wide range of processes operating at different time and length scales. The fastest process at any given length scale tends to be the dominant control. Applying this principle to the array of physical processes that operate within magma flow pathways leads to some key insights into the origins of magmatic Ni-Cu-PGE sulfide ore deposits. A high proportion of mineralised systems, including those in the super-giant Noril'sk-Talnakh camp, are formed in small conduit intrusions where assimilation of country rock has played a major role. Evidence of this process is reflected in the common association of sulfides with varitextured contaminated host rocks containing xenoliths in varying stages of assimilation. Direct incorporation of S-bearing country rock xenoliths is likely to be the dominant mechanism for generating sulfide liquids in this setting. However, the processes of melting or dissolving these xenoliths is relatively slow compared with magma flow rates and, depending on xenolith lithology and the composition of the carrier magma, slow compared with settling and accumulation rates. Chemical equilibration between sulfide droplets and silicate magma is slower still, as is the process of dissolving sulfide liquid into initially undersaturated silicate magmas. Much of the transport and deposition of sulfide in the carrier magmas may occur while sulfide is still incorporated in the xenoliths, accounting for the common association of magmatic sulfide-matrix ore breccias and contaminated "taxitic" host rocks. Effective upgrading of so-formed sulfide liquids would require repetitive recycling by processes such as reentrainment, back flow or gravity flow operating over the lifetime of the magma transport system as a whole. In contrast to mafic-hosted systems, komatiite-hosted ores only rarely show an association with externally-derived xenoliths, an observation which is partially due to the predominant formation of ores in lava flows rather than deep-seated intrusions, but also to the much shorter timescales of key component systems in hotter, less viscous magmas. Nonetheless, multiple cycles of deposition and entrainment are necessary to account for the metal contents of komatiite-hosted sulfides. More generally, the time and length scale approach introduced here may be of value in understanding other igneous processes as well as non-magmatic mineral systems.
基金Project supported bythe National Natural Science Foundation of China (40472052)
文摘REE geochemical characteristics of the magmatic rocks and gold deposits in Shizishan ore-field of Tongling were studied. Three types of the magmatic rocks have almost the same chondrite-normalized REE patterns, Eu and Ce anomalous values, and ∑REE, ∑LREE/∑HREE regular changes, which indicates that their magmas come from the same source and their digenetic mechanism is fractional crystallization. In three gold deposits, the mineral ores and related altered rocks have similar chondrite-normalized REE patterns and sharp Eu positive anomalous values. The REE contents reduced from the magmatic rocks to skamization or alteration magmatic rocks, skam type ores, sulphide type ores, wall-rocks limestone or marble. The REE geochemical characteristics of the ores and related rocks show that primary fluids originated from magmatic differentiation in lower pressure of shallow crust, ore-forming hydrothermal solutions gained REE and mineralization elements further from leaching the magmatic rocks, then superimposed and reformed the limestones or marbles and deposited ore-forming material.
基金financially supported by funds of the National Key R&D Program of China (Grant Nos. 2018YFC0604004 and 2017YFC0601206)
文摘A great number of magmatic Cu-Ni deposits(including Kalatongke in Xinjiang and Hongqiling in Jilin) are distributed over a distance of almost 3000 km across the Tianshan-Xingmeng Orogenic Belt, from Tianshan Mountains in Xinjiang in the west, to Jilin in eastern China in the east. These deposits were formed during a range of magmatic episodes from the Devonian to the Triassic. Significant magmatic Cu-Ni-Co-PGE deposits were formed from the Devonian period in the Nalati arc(e.g. Jingbulake Cu-Ni in Xinjiang), Carboniferous period in the Puerjin-Ertai arc(e.g. Kalatongke Cu-Ni-Co-PGE in Xinjiang), Carboniferous period in the Dananhu-Touquan arc(e.g. Huangshandong, Xiangshan and Tulaergen in estern Tianshan, Xinjiang) to Triassic period in the Hulan arc(e.g. Hongqiling Cu-Ni in Jilin). In addition to the overall tectonic, geologic and distribution of magmatic Cu-Ni deposits in the Tianshan-Xingmeng Orogenic Belt, the metallogenic setting, deposit geology and mineralization characteristics of each deposit mentioned above are summarized in this paper. Geochronologic data of Cu-Ni deposits indicate that, from west to east, the metallogenic ages in the Tianshan-Xingmeng Orogenic Belt changed with time, namely, from the Late Caledonian(~440 Ma), through the Late Hercynian(300-265 Ma) to the Late Indosinian(225-200 Ma). Such variation could reflect a gradual scissor type closure of the paleo Asian ocean between the Siberia Craton and the North China Craton from west to east.
文摘Deep seated magmatic liquation injection deposits form a major type of magmatic sulfide deposit in China. The reserves of nickel and copper in this type of deposit may attain several hundred thousand tons (e.g.Hongqi 7 and Karatunggu) to nearly ten million tons (e.g.Jinchuan). Those deposits can be classified as large or superlarge deposits. The ore grade is relatively high, commonly with w (Ni)>1 %. The mineralized intrusions are small in size, generally only 0.0 n km 2 to 0. n km 2, with the largest one not exceeding a few km 2. Before intruding, the primary magmas have undergone liquation and partial crystallization at depth; as a result, the magmas have partitioned into barren magma, ore bearing magma, ore rich magma and ore magma, which then ascended and injected into the present locations once or multiple times, to form ore deposits. The above mentioned mineralizing process is known as deep seated magmatic liquation injection mineralization. The volume of the barren magma is generally much larger than those of the ore bearing magma, ore rich magma and ore magma. In the ascending process, most of the barren magma intruded into different locations or outpoured onto the ground surface, forming intrusions or lava flows. The rest barren magma, ore bearing magma, ore rich magma and ore magma may either multiple times inject into the same place in which rocks and ores are formed or separately inject into different spaces to form rocks and ores. Such deep seated magmatic liquation injection deposits have a much smaller volume, greater ore potential and higher ore grade than those of in situ magmatic liquation deposits. Consequently, this mineralizing process leads to the formation of large deposits in small intrusions.
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The Jinchuan magmatic Ni-Cu deposit,located in the Longshou Mountain region,is the largest producer of Ni and Cu in China,with mineralization being related to mafic and ultramafic magmatism.Previous studies have shown that the Longshou Mountain was combined with the Qilian Mountains before Neoproterozoic,and was separated from each other due to the opening of late Qilian oceanic basin in the Paleozoic.The relict Precambrian microcontinents of the Longshou Mountain and Qilian Mountain
基金supported by grants from the National Key Research and Development Program of China(Grant Nos.2016YFC0600310 and 2019YFA0708602)the National Natural Science Foundation of China(Grant Nos.41702091,41872083 and 42022014)+2 种基金the Yunnan Applied Basic Research Project(Grant No.202101AT070073)the China Fundamental Research Funds for the Central Universities(Grant No.2652018133)the Scientific Research Fund of the Yunnan Provincial Education Department(Grant No.2022Y016)。
文摘The Habo deposit is a typical porphyry Cu-Mo deposit in the Ailaoshan–Red River metallogenic belt.Ore minerals in the Habo deposit typically occur as veins in the monzonite porphyry.Zircon U-Pb dating suggests that the monzonite porphyry formed at 35.07±0.38 Ma.The monzonite porphyry is characterized by high SiO_(2),Al_(2)O_(3),K_(2)O and Na_(2)O contents,with A/CNK ratios ranging from 0.97 to 1.02.All samples exhibit fractionated REE patterns,characterized by high(La/Yb)N ratios(9.4–13.6,average of 11.2).They show adakite-like geochemical features,high Sr concentrations(627–751 ppm,average of 700 ppm),low Y concentrations(15.13–16.86 ppm,average of 15.81 ppm)and high Sr/Y values(39.5–47.4,average of 44.3).These samples have high initial^(87)Sr/^(86)Sr ratios(0.7074–0.7076)and negativeεNd(t)values(-5.1 to-3.7),whereas the zirconεHf(t)values range from-2.2 to+0.4,suggesting that the monzonite porphyry was derived from the partial melting of a thickened juvenile lower crust.The oxygen fugacity,calculated on the basis of the chemical composition of the amphiboles,shows?NNO values ranging from+1.65 to+2.16(average of 1.94)and lg(fO_(2))ranging from-12.72 to-11.99(average of-12.25),indicating that the monzonite porphyry has high oxygen fugacity.Zircons have high Ce^(4+)/Ce^(3+)ratios(29.29–164.24,average of 84.92),with high?FMQ values ranging from+0.50 to+1.51(average of 0.87)and high lg(fO_(2))values ranging from-14.72 to-12.85(average of-14.07),which also indicates that the oxygen fugacity of the magma was high.The dissolved water content of the Habo monzonite porphyry is 9.5–11.5 wt%,according to the geochemical characteristics,zircon-saturation thermometry(692–794°C)and the mineral phases(amphibole,no plagioclase)in the deep magma chamber.Combined with previous studies,we propose that the high oxygen fugacity and high water content of magma played key roles in controlling the formation of the Habo and other Cu-Mo-Au deposits in the Ailaoshan–Red River metallogenic belt.
基金supported by NSFC(Grant Nos.40072037,40273025)NKBRSF Project(Grant No.G1999043200)
文摘Primitive mantle normalized Platinum group elements (PGE) concentration patterns for the Zhengziyanwo intrusion and Dashibao Formation basalts are of positive slope, similar to most of the world class magmatic Ni Cu PGE sulfide deposits. Characters of this intrusion and its related ores and Dashibao Formation basalts are their negative Pt anomaly and high concentration of Rh relative to Pt and Pd, facts being interpreted to be the results of crystallization and fractionation of Pt alloys and spinel phase free crystallization history for the magma, respectively. PGE parameters of the Dashibao Formation basalts are consistent with the general trend of those found for the Zhengziyanwo intrusion, and this might infer a genetic link between them.
文摘The Wangershan gold deposit and spatially related Shangzhuang granite, eastern Shandong Province, have been precisely dated by 40 Ar/ 39 Ar laser incremental heating technique. Magmatic hornblende and biotite, collected from the Shangzhuang granites, yielded well-defined and reproducible plateau ages at 128.1-127.5 and 124.4-124.1 Ma (2 σ ), measuring the cooling ages of the intrusion at ca. 500 ℃ and 300-350 ℃, respectively. Hydrothermal sericite extracted from auriferous vein gave high-quality plateau ages between (120.6±0.3) Ma and (120.0±0.4) Ma (2 σ ). Given the similarity of the closure temperature for argon diffusion (300-350 ℃) in the sericite mineral to the homogenization temperature of primary fluid inclusions in the quartz from gold ores, and the intergrowth of sericite with native gold, present 40 Ar/ 39 Ar sericite ages can be reliably interpreted in terms of the mineralization age for the Wangershan deposit. 40 Ar/ 39 Ar hornblende and biotite ages permit an estimate for the cooling rate of the Shangzhuang granite at about 50 ℃/Ma. There are abundant intermediate-mafic dikes in most gold camps of eastern Shandong, whose ages of formation have been previously constrained mainly at 121-119 Ma. The temporal association between the Shangzhuang granite, the Wangershan gold deposit, and the widespread dikes confirms that intrusive activity, gold mineralization, and dike emplacement in this region were broadly coeval, reflecting significant continental lithosphere thinning and resulting crustal extension of Early Cretaceous in eastern China.
基金financially supported by the China State Mineral Resources Investigation Program (Grant No.12120114013701 and 1212011120608)
文摘The Wenyu copper polymetallic deposit, with proven reserves of about 0.23 Mt Cu, 394 t Ag and 0.04 Mt Pb, is located in the central part of the Lancangjiang volcanic rock belt (Fig. l a), which is one of the most potential copper polymetallic exploration areas in SW China.
基金financially supported by the National Natural Science Foundation of China(grant No.41302061)
文摘Rare metal ore reserves are an important strategic resource, and their metallogenic mechanism and mineralization studies have also been received widespread international attention.
基金This research project was financially supported jointly by the Key Research Project (No. KZCX3-SW-125) of CAS and the National Natural Science Foundation of China (No. 40172037).
文摘In order to study the characteristics of sea-floor exhalative sedimentary and magmatic hydrothermal superimposition on the Bainiuchang polymetallic deposit, the REE compositions of the granites, host-rocks and ores have been systematically analyzed by ICP-MS. As viewed from their REE compositions, the granites show obvious negative Eu anomalies and weak negative Ce anomalies. According to their REE characteristics, the host-rocks were derived partly from sea-floor exhalative sediments. In terms of their REE compositions, the ores can be divided into two groups: one group, of which the samples were collected from the Baiyang segment relatively far away from the Bozhushan granite batholith, possesses positive Eu anomalies or no Eu anomaly and negative Ce anomalies, indicating that ore-forming hydrothermal fluid was relatively reductive and its temperature was higher than 250 ℃. Furthermore, the coinstantaneous presence of positive Eu anomalies and negative Ce anomalies indicate that the convective mixing of a little amount of seawater with hydrothermal fluid had happened while ores were precipitated on ancient sea floor. The other group, of which the samples were mainly collected from the Chuanxindong and Duimenshan segments near the Bozhushan granite batholith, has similar chondrite-monalized REE distribution patterns to those of the magmatic rocks. But as a whole, the REE characteristics of both groups change gradually starting from the Bozhushan granite batholith. Based on the REE characteristics of the granites, host-rocks and ores, it is suggested that the ore-forming metals seem to have come from several different sources.
基金the 8th Geological Brigade of Aksu,Xinjiang, the Institute of Geology of the Chinese Academy of Geological Sciencesthe Beijing Research Institute of Uranium Geology,CNNC
文摘Objective The Sachakou Pb-Zn polymetallic deposit is located in Hetian County, Xinjiang (geographical coordinates of E78° 57' 54.30"-78°59' 53.63", N34° 39' 27.50"-34° 40' 57.21"). It belongs to the West Kunlun orogenic belt on the northwest edge of the Qinghai-Tibet Plateau and is connected to the Sanjiang orogenic belt to the south (Spurlin et al., 2005). In recent years, a series of Pb-Zn mineralized spots and deposits have been discovered in this area one after another, which is called the Huoshaoyun ore concentration area. Among them, the Sachakou Pb-Zn deposit has reserves up to140 Mt, which has reached a large scale. However, the study on the genesis of deposits in this area has only just begun. This work studied the genesis ofthis Pb-Zn deposit in order to provide new ideas for the genesis of regional deposits and regional prospecting.
基金supported by projects from Chinese Geological Survery Programme (12120115035601)
文摘1 Introduction The uranium deposits related with Indosinian and Yanshanian granite have provided the abundant resource of uranium during the past several decades in China.The deposits are mainly distributing in the Guidong granite