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YANG Ruiyan MA Dongsheng BAO Zhengyu PAN Jiayong CAO Shuanglin XIA Fei 《中国科学D辑(英文版)》2006,49(8):862-871
1 Introduction The Mid-Hunan Basin is located in the south mar- gin of the Ancient Island Arc of Dong’an-Xuefeng and the north part of the interarc basin of Hercynian- Indosinian in Hunan-Guangxi. The basement rock of the basin, which is mainly distributed along the mar- ginal area of the basin and some interior sub-uplifts, is composed of pre-Devonian epimetamorphic-clastic rocks in great thickness, and the cap rock of the basin are dominated by carbonate rock and clastic rocks of Paleo… 相似文献
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浙江大桥坞矿床是赣杭火山岩铀成矿带重要的铀矿床之一。本文通过对大桥坞铀矿床铅、氢和氧同位素及前人资料的综合研究,探讨了矿床成矿流体和成矿物质来源。结果表明花岗斑岩、凝灰岩、辉绿岩、矿石中黄铁矿、蚀变围岩中黄铁矿的Ph同位素组成变化较小,可能指示它们具有相似的源区。在铅同位素构造环境判别图解中,铅同位素投影点分布范围较广,但多数集中于地幔和造山带演化线之间,偏向造山带,反映了铅的来源与岩浆活动有关。氢、氧同位素组成显示,成矿流体主要来自大气降水。成矿物质来源于壳幔混合源。 相似文献
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Geochemistry of ore-forming fluids and geological significance 总被引:1,自引:0,他引:1
The Kuoerzhenkuola gold field (including the Kuoerzhenkuola and the Buerkesidai gold deposits) is the most important one in
the Sawuer gold belt, northern Xinjiang, China. Isotopic studies including D, O, He, C, S, Pb and Sr reveal that the ore-forming
fluids of the Kuoerzhenkuola and the Buerkesidai deposits shared the same source: the water of ore fluids was magmatic water
and minor meteoric water; the mineralizers and ore materials derived mainly from mantle beneath the island arc, and partially
from crust. The ore-forming fluids of two deposits are a mixture of mantle-derived fluids incorporated by crust-derived fluid,
and meteoric water. Based on these results, combined with the consideration of the tectonic setting and geological features,
we suggest that the two gold deposits in the Kuoerzhenkuola gold field, Sawur gold belt share the same genesis, and are volcanogenic
hydrothermal gold deposits occurring in the same caldera. 相似文献
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Most metallic minerals in ore deposits are sulfides. When a sulfide mineral coexists with rock-forming minerals, its solubility
is distinctly different from itself alone. The change in dissolution character of a mineral with coexisting rock-forming minerals
leads to particular geochemical behavior. The concept of solubility of a metallic mineral with coexisting rock-forming minerals
and its theory and model of calculation are put forward. Taking Tianmashan Cu-Au ore deposit of sulfide minerals in Tongling
district as an example, solubilities of some metallic minerals with other coexisting minerals, such as pyrite or chalcopyrite
with quartz (representing sandstone) or calcite (representing limestone), are calculated. The results show the mechanism of
ore-forming processes. As the ore-forming fluid flows through sandstone, it dissolves pyrite in the sandstone at first, then
transports the iron and sulfur to the interface between sandstone and limestone and eventually precipitates them on the interface. 相似文献
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Changkeng Au-Ag deposit is a newly-discovered new type precious metal deposit. N2-Ar-He systematics studies and3He/4He and δD- δ18O composition analyses show that the ore-forming fluid of the deposit is composed mainly of formation water (sedimentary brine)
but not of meteoric water, which was thought to be source of the ore-forming fluid by most previous researchers. The content
of mantle-derived magmatic water in the ore-forming fluid is quite low, usually lower than 10%. According to the source of
the ore-forming fluid, the Changkeng Au-Ag deposit should belong to sedimentary brine transformed deposits. From the Late
Jurassic to the Early Cretaceous Period, with deposition and accumulation of thick sediments in Sanzhou Basin, the formation
water in the sedimentary layers was expelled from the basin because of overburden pressure and increasing temperature. The
expelled fluid moved laterally along sedimentary layers to the margin of the basin, and finally moved upward along a gently-dipping
interlayer fault. Because of a decline in pressure and temperature, ore minerals were deposited in the fault.
Project supported by the National Natural Science Foundation of China (Grant No. 495020291, the Natural Science Foundation
of Zhongshan University, the Research Foundation of National Key Laboratory of Metallogenesis in Nanjing University (Grant
No. 039704) and the Lingnan Foundation. 相似文献
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SHEN Ping SHEN Yuanchao LIU Tiebing LI Guangming & ZENG Qingdong Institute of Geology Geophysics Chinese Academy of Sciences Beijing China 《中国科学D辑(英文版)》2005,48(11)
The Kuoerzhenkuola gold field (including the Kuo- erzhenkuola and the Buerkesidai gold deposits), lo- cated 68 km east of Jimunai County in northern Xing- jiang, China, is an important component of the Sawuer gold belt which is the eastward extending part of the Zarma-Sawur gold-copper belt in Kazakhstan. Some studies are concerned with the geology of the gold ores[1―3], the associated volcanic rocks[4], radiogenic isotope[5―8], and the ore-forming environment[8]. Most researchers inferr… 相似文献
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Metallogensis of the Xiadian gold deposit in Shandong Province has been a question under dispute for a long time. There are many points such as metamorphic hydrothermal, magamatic hydrothermal and meteoric water. Detailed study shows that mantle-rooted fluids were involved in the ore-forming processes. Evidence for this argumentation comes from: (1) discordogenic fault; (2) intersecting and accompanying of basic veins and lodes; (3) geochemistry of stable isotopes; (4) geochemistry of fluid inclusions; and (5) multi-level circulation and exchanging of mantle-rooted fluids. Based on the characteristics of the circulation system of mantle-rooted fluids and its close relation to magmatic hydrothermal fluids and meteoric water, ore-bearing fluids are divided into three subsystems: (1) C-H-O-rich fluid circulation subsystem in mantle, (2) Si-rich fluid circulation subsystem in the middle and lower crust; and (3) S-rich fluid circulation subsystem in shallow and surface crust. Ore-forming functions of these subsystems are controlled respectively by their different geodynamic settings. 相似文献
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Strontium isotope geochemistry of the Lemachang independent silver ore deposit, northeastern Yunnan, China 总被引:3,自引:0,他引:3
Sr isotope geochemical studies (the 87Sr/86Sr and ?18O-87Sr/86Sr systems) on the wall rocks and ores from the Lemachang independent Ag deposit in northeastern Yunnan provide strong evidence that the ore-forming fluids had flown through radiogenetically Sr-enriched rocks or strata prior to their entry into the locus of ore precipitation, and water-rock interaction is the main mechanism of Ag ore precipitation. The radiogenetically Sr-enriched source region may be the Proterozoic basement (the Kunyang and Hekou groups). Moreover, the theoretical modeling of the Sr isotopic system indicates that the ore-forming fluids contain as much as 3×10?6 Sr with isotopic composition of Sr being 0.750 and that of oxygen 7.0‰. The ore-forming temperatures were estimated at 150-250℃ for the carbonate rock-type ores and at 200-260℃ for the clastic rock-type. 相似文献
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The study results of He and Ar isotopes from fluid inclusions in pyrites formed during mineralization stage of Jinding superlarge
Pb-Zn deposit in west Yunnan, China are reported. The data show that the40Ar/36Ar and3He/4He ratios of fluid inclusions are respectively in the range of 301. 7–385. 7 and 0. 03–0.06Ra, suggesting the oreforming fluid
is a kind of air saturated meteoric groundwater. On the basis of research on coupled relationships among He, Ar, S and Pb
isotopes, the evolution history of ore-forming fluid of the deposit can be summarized as (i) air saturated meteogenic groundwater
infiltrated down and was heated→ (ii) leached S, C and radiogenic He, Ar from the basinal strata → (iii) leached Pb and Zn
from mantle-derived igneous rocks located in the bottom of the basin→ (iv) ore-forming fluid ascended and formed the deposit.
Due to this process, the isotope signatures of crustal radiogenic He, atmospheric Ar (with partial radiogenic40Ar), crustal S and mantle-derived Pb remained in the ore-forming fluid.
Project supported by A30 Project of the National Climbing Program of China and University of Manchester. 相似文献
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Crude oil as carrier of gold: petrological and geochemical evidence from Lannigou gold deposit in southwestern Guizhou, China 总被引:1,自引:0,他引:1
Organic matter is related closely to mineralization of Lannigou gold deposit in southwestern Guizhou, China. Regionally, the
distribution of organic carbon agrees well with that of faults within which gold deposits are hosted. Studies on organic petrology
show that pyrobitumen, which is related most closely to mineralization, adheres to quartz vein or fills quartz veinlet. Proton-induced
X-ray emission (PIXE) analysis shows an evident abundance of Au in pyrobitumen. Pyrobitumen paragenetically associates with
pyrite and arsenopyrite which are the main carrier minerals of Au. The thermal simulation experiment indicates that about
99% of Au will be concentrated in oil phase in the coexisting system of oil and brine and rock. The role of crude oil in ore-forming
process is: as carrier of Au, crude oil moves upwards, and undergoes thermal decomposition and thermochemical reduction when
it encounters the oxidizing fluid within the Trassic turbidity; Au is thus released from crude oil, reduced and precipitated.
Project supported by the Climbing Project (No. PA30) and the National Natural Science Foundation of China (Grant No. 49673190). 相似文献
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The Xiaoxinancha Au-rich copper deposit is one of important Au-Cu deposits along the continental margin in Eastern China. The deposit consists of two sections: the Beishan mine (North), composed of altered rocks with veinlet-dissemination sulfides and melnicovite-dominated sulfide-quartz veins, and the Nanshan mine (South), composed of pyrrhotite-dominated sulfide-quartz veins and pure sulfide veins. The isotope compositions of noble gases extracted from fluid inclusions in ore minerals, i.e. ratios of 3He/4He, 20Ne/22Ne and40Ar/36Ar are in the ranges of 4.45―0.08 Ra, 10.2―8.8 and 306―430, respectively. Fluid inclusions in minerals from the Nanshan mine have higher 3He/4He and 20Ne/22Ne ratios whereas those from the Beishan mine have lower 3He/4He ratios. The analysis of origin, and evolution of the ore fluids and its relations with the ore-forming stages and the ages of mineralization suggests that the initial hydrothermal fluids probably come from the melts generated by partial melting of oceanic crust with the participation of fluids from the mantle (mantle-plume type)/aesthenosphere. This also corresponds to the continental margin settings during the subduction of Izanagi ocaneic plate towards the palaeo-Asian continent (123―102 Ma). The veinlet-dissemination ore bodies of the Beishan mine were formed through replacement and crystallization of the mixed fluids generated by mixing of the ascending high-temperature boiling fluid with young crustal fluid whereas the melnicovite-dominated sulfide-quartz veins were formed subsequently by filling of the high-temperature ore fluid in fissures. Pyrrhotite-dominated sulfide-quartz veins in the Nanshan mine were formed by filling-deposition-crystallization of the moderate-temperature ore fluids and the pure sulfide veins were formed later by filling-deposition-crystallization of ore substance-rich fluids after boiling of the moderate-temperature ore fluids. The metallogenic dynamic processes can be summarized as: (1) formation of fluidand ore substance-bearing Adakitic magma by degassing, dewatering and partial melting during subduction of the Izanagi plate; (2) separation and formation of ore fluids from the Adakitic magma; and (3) success-sive ascending of the ore fluids and final formation of the Au-rich Cu deposit of veinlet-dissemination and vein types by secondary boiling. 相似文献
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Re-Os isotope dating of molybdenites in the Huang-shaping Pb-Zn-W-Mo polymetallic deposit, Hunan Province, South China and its geological significance 总被引:11,自引:0,他引:11
YAO JunMing HUA RenMin QU WenJun QI HuaWen LIN JinFu & DU AnDao State Key Laboratory of Crust-Mantle Evolution Mineralization Department of Earth Sciences Nanjing University Nanjing China Institute of Rock Mineral Analysis Chinese Academy of Geological Sciences Beijing China Institute of Geochemistry Chinese Academy of Sciences Guiyang China Department of Resources Environment Engineering Guilin Institute of Technology Guilin China 《中国科学D辑(英文版)》2007,50(4):519-526
The large-scale Huangshaping Pb-Zn-W-Mo polymetallic deposit is located in the central Nanling min- eralization zone, South China. Six molybdenite samples from the Huangshaping deposit were selected for Re-Os isotope measurement in order to define the mineralization age of the deposit. It yields a Re-Os isochron age of 154.8±1.9 Ma (2σ ), which is in accordance with the Re-Os model ages of 150.9― 156.9 Ma. This age is about 7 Ma younger than their host granite porphyry, which was dated as 161.6±1.1 Ma by zircon U-Pb method using LA-ICPMS. All these ages demonstrate that the Huang- shaping granite and related Pb-Zn-W-Mo deposit occurred in the middle Yanshanian period, when many other granitoid and related ore deposits emplaced and formed, e.g. the Qitianling granite and Furong tin deposit, the Qianlishan granite and giant Shizhuyuan W-Sn-Mo-Bi deposit and Jinchuantang Sn-Bi deposit in the nearby area. They constitute the main part of the magmatic-metallogenic belt of southern Hunan, and represent the large-scale metallogeny in middle Yanshanian in the area. The lower rhenium content in molybdenite of Huangshaping deposit suggests that the ore-forming material was mainly of crust origin. 相似文献
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Starting with the research status of bio-metallogenesis of TI deposits and their geology, this work deals with the geological
background of TI enrichment and mineralization and the mechanism of bio-metallogenesis of TI deposits, as exemplified by TI
deposits in the low-temperature minerogenetic province. This research on the bio-metallogenesis of TI deposits is focused
on the correlations between bio-enrichment and TI, the enrichment of TI in micro-paleo-animals in rocks and ores, bio-fossil
casts in TI-rich ores, the involvement of bio-sulfur in minerogenesis and the enrichment of bio-genetic organic carbon in
TI ores. Thallium deposits have experienced two ore-forming stages: syngenetic bio-enrichment and epigenetic hydrothermal
reworking (or transformation). Owing to the intense epigenetic hydrothermal reworking, almost no bio-residues remain in syngenetically
bio-enriched TI ores, thereby the TI deposits display the characteristics of hydrothermally reoworked deposits.
Supported by the National Natural Science Foundation of China (Grant No. 40372047) 相似文献
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Study of tectonic layering motion and layering mineralization in the Tongling metallogenic cluster 总被引:7,自引:0,他引:7
TheTonglingarea,animportantmetallogeniccluster,isrichiniron,sulphurandgold.Mineralizationiscorrelatedcloselytotheevolutionofthestrata,magmatiteandtectonics[1—4].SkarnmineralizationdevelopedwellintheTonglingarea.ItappearsalongmainlyonseveralinterfacesofPe… 相似文献
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Ore-forming fluid and metallization of the Huanggangliang skarn Fe-Sn deposit, Inner Mongolia 总被引:2,自引:0,他引:2
Two kinds of inclusions, fluid-melting inclusion and gas-liquid inclusion, are present in the Huanggangliang deposit in eastern
Inner Mongolia. Temperature ranges from 1050°C of fluid-melting inclusion to 150°C of liquid inclusion. Away from intrusion,
the inclusions of orebodies intend to be characterized by simpler type, lower temperature and lower salinity, as well as weakened
relation to intrusion. The metallization of the Huanggangliang deposit is characterized by multiple activities of ore-forming
fluid, multi-source, multi-stage accumulation of ore-forming material, F-rich environment, enrichment of F, organic gas, CO2 and N2, and involving of residual magma. 相似文献
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《Acta Geochimica》2017,(3)
Xianglushan-type iron deposits are one of the new types of iron deposits found in the Weining Area of Western Guizhou. The iron-bearing rock system is a paleo-weathered crustal sedimentary(or accumulating) stratum between the top of the Middle-Late Permian Emeishan basalt formation and the Late Permian Xuanwei formation. Iron ore is hosted in the Lower-Middle part of the rock system. In terms of the genesis of mineral deposit, this type of deposit should be a basalt paleo-weathering crustal redeposit type, very different from marine sedimentary iron deposits or continental weathering crust iron deposits. Based on field work and the analytical results of XRD Powder Diffraction, Electron Probe, Scanner Electron Microscope, etc., the geological setting of the ore-forming processes and the deposit features are illustrated in this paper. The ore-forming environment of the deposit and the Emeishan basalt weathering mineralization are also discussed in order to enhance the knowledge of the universality and diversity of mineralization of the Emeishan Large Igneous Province(ELIP), which may be a considerable reference to further research for ELIP metallogenic theories, and geological research for iron deposits in the paleo-weathering crust areas of the Emeishan basalt,Southwestern, China. 相似文献
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Sources of ore-forming fluids and metallic materials in the Jinwozi lode gold deposit, eastern Tianshan Mountains of China 总被引:4,自引:0,他引:4
This paper presents gas compositions and H-, O-isotope compositions of sulfide- and quartz-hosted fluid inclusions, and S-, Pb-isotope compositions of sulfide separates collected from the principal Stage 2 ores in Veins 3 and 210 of the Jinwozi lode gold deposit, eastern Tianshan Mountains of China. Fluid inclusions trapped in quartz and sphalerite are dominantly primary. H- and O-isotopic compositions of pyrite-hosted fluid inclusions indicate two major contributions to the ore-forming fluid that include the degassed magma and the meteoric-derived but rock 18O-buffered groundwater. However, H- and O-isotopic compositions of quartz-hosted fluid inclusions essentially suggest the presence of groundwater. Sulfide-hosted fluid inclusions show considerably higher abundances of gaseous species CO2, N2, H2S, etc. Than quartz-hosted ones. The linear trends among inclusion gaseous species reflect the mixing tendency between the gas-rich magmatic fluid and the groundwater. The relative enrichment of gaseous species in sulfide-hosted fluid inclusions, coupled with the banded ore structure indicating alternate precipitation of quartz with sulfide minerals, suggests that the magmatic fluid has been inputted to the ore-forming fluid in pulsation. Sulfur and lead isotope compositions of pyrite and galena separates indicate an essential magma derivation for sulfur but the multiple sources for metallic materials from the mantle to the bulk crust. 相似文献