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Acta Geologica Sinica(English Edition) 1996年第4期70卷 366-379,452页

作者： Liu Wei,research center of mineral resources exploration, chinese academy of Sciences, chinese academy of Sciences, BeijingHe Baichu, Changsha Institute of Geotectonics, chinese academy of Sciences, Changsha, Hunanand Chen ZhenshengYichang Institute of Geology and mineral resources, chinese academy of GeologicalSciences, Yichang, Hubei

Coexisting quartz, feldspar and biotite vary widely in their δ18O values and display a remarkable 18O/16O disequilibrium relation; especially, a quartz-feldspar reversal (△ 18OQUartz_feldsparminerals is misleading and unreliable. Experiments carried out by the authors show that the 18O / 16O exchange reaction is not accompanied by what geologists describe as petrological and mineralogical alteration effect. This decoupling relation implies that exchange reaction occurs at a relatively high temperature during subsolidus-postmagmatic cooling of magmas. The exchange mechanism is mainly diffusion-controlled. It is demonstrated through quantitative modelling that the hydrothermal system associated with the Aral pluton is long-lived (0.8-6 Ma), with a relatively high fluid flow rate (3 ×10-14 mol. s-1) and high W/ R ratio (0.79-6.14). This means that an intense flow and convection may exist at the midcrustal level of erogenic magmatic arcs.

关键词： kinetics oxygen isotope exchange reaction granite Aral of Xinjiang

Oxygen and hydrogen isotopic compositions of coexistent minerals of the Tasigake alkali granite pluton,northern Xinjiang:constraints upon the cause of ^(18)O-D depletion and the ^(18)O/^(16)O exchange kinetics

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chinese Science Bulletin 1999年第12期44卷 1086-1093页

作者： LIU Wei, ZHAO Zhenhua ZHANG Fuqin research center of mineral resources exploration, Institute of Geophysics , chinese academy of Sciences , Beijing 100101, China Guangzhou Institute of Geochemistry, chinese academy of Sciences , Guangzhou 510640, China research center of mineral Resource exploration Institute of Geophysics Chinese Academy of Science Beijing China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Oxygen and hydrogen isotopic compositions have been determined of three coexistent mineral triplets of alkali feldspar, quartz, arfvedsonite of 11 samples collected from the Tasigake alkali granite pluton, Ulungur River region, northern Xinjiang. Isotopic exchange with meteoric water during subsolidus cooling caused strong 18O-D depletion and the remarkable nonequilibrium 18O/16O relation between coexistent minerals. 18O/16O exchange kinetic effects of the three minerals are simultaneously and consistently modelled. Exsolution and microtextural reorganization of alkali feldspar, and infiltration of water have been mutually facilitated by each other. Shallow intrusion, and circulation of meteoric water throughout the pluton cool it effectively. As a result, the "heat engine" is rapidly extinguished, and the nonequilibrium 18O/16O relation is frosen.

关键词： 18O-D depletion isotopic exchange kinetics alkali granite Ulungur.

Study on Sulfide-melt Inclusions in Mantle Xenoliths of Xinchang, Zhejiang

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International Journal of minerals,Metallurgy and Materials 2000年第1期14卷 5-9页

作者： Jiuhua Xu Xuelei Chu YulingXie Fenglei Bie Dayi Qian University of Science and Technology Beijing, Beijing 100083, China China University of Geosciences, Beijing 100083, China the research center of mineral resources exploration, chinese academy Univ Sci & Technol Beijing Beijing 100083 Peoples R China China Univ Geosci Beijing 100083 Peoples R China chinese Acad Sci Res Ctr Mineral Resources Explorat Beijing 100101 Peoples R China chinese Acad Sci Inst Geol Beijing 100029 Peoples R China

In minerals of mantle xenoliths captured within Tertiary alkali-basalt from Xinchang, Zhejiang province, China, many sulfidemelt inclusions were found by the observation of polished thin section. Electron microprobe analysis has been applied to detect the components of sulfide-melt inclusions. The result shows that the sulfide phases of inclusions are mainly pentlandite, and secondarily pyrrho- tite, The molar ratio of Ni to Fe, r_Ni,/r_Fe, of mineral phases in sulfide inclusions is related to olivine contents in host mantle xenoliths. The r_Ni/r_Ni, of sulfides from Xinchang samples has a possitive correlation to r_(Fe+Ni),/r_S. The r_(Fe+Ni),/r_S, becomes higher with the increasing of r_Ni/r_Fe In single sulfide-melt inclusions, r_Ni,/r_Fe, r_(Fe+Ni),/r, and Ni contents increase from the center to edge, reflecting a result of different cooling speed in an inclusion. A comparison between the data from Hannuoba, West Eifel of Germany and Nograd-Gomor of east Europe suggests that the composition of the inclusions is different for each area, which indicated that a regional differentiation of sulfide in mantle fluids.

关键词： mantle xenolith sulfide-melt inclusion electron microprobe analysis, Xinchang

A special intermediate-low temperature PGE-As-Co mineralization

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chinese Science Bulletin 1999年第S2期44卷 42-44页

作者： WANG Jingbin, WANG Yuwang and WANG Lijuan Beijing Institute of Geology for mineral resources, China National Nonferrous Metal Industry Corporation, Beijing 100012 China research center of mineral resources exploration, chinese academy of Sciences, Beijing 100101, China

THIS paper introduces a new type of platinum-group elements (PGE) mineralization formed under a special condition of intermediate to low temperature, i. e. Huanggang PGE-As-Co deposit related to cryptoex-plosive hornblendite, Inner Mongolia, of which the proven reserves of arsenic reached small size. 1 Geology of mineral district Huanggang PGE-As-Co deposit, located at the margin of Huanggang Mesozoic volcanic basin in thesouthern part of Da Hinggan Range, was controlled by both Huanggang-Ganzhuermiao deep fracture andvolcanic apparatus. The volcanic apparatus in a protruding cupola land-form is about 0.25 km^2. It wasfilled with rhyolitic volcanic breccia, brecciated tuff, subvolcanic dacite porphyry and brecciated lava ofvolcanic neck facies. The host hornblendite, of which Rb-Sr isochron age (bulk rock) is (90.66 ±14.44) Ma, intruded into the apparatus in the form of irregular dike (figure 1).

关键词： intermediate-low temperature PGE-As-Co mineralization Inner Mongolia.

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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chinese Science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. the research center of mineral resources exploration , chinese academy of Sciences , Beijing 100101, China 2. Institute of Geology , chinese academy of Sciences , Beijing 100029, China 3. Institute of High Energy Physics , chinese academy of Sciences , Beijing 100817 , China 4. Beijing University of Science and Engineering , Beijing 100083, China Corresponding author the research center of mineral resources exploration Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China Beijing University of Science and Engineering Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Auriferous karst breccias in East Hebei Province, China

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chinese Science Bulletin 1999年第S2期44卷 269-271页

作者： LIU Jianming~1, LIU Yanxuan~2, TAN Jun~1, CHEN Xurui~1 and HUO Weiguo~1 1. research center for mineral resources exploration, chinese academy of Sciences, Beijing 100101, China 2. Qingheyan Gold Mine, Qinglong County, Hebei 066500, China research center for mineral resources exploration Chinese Academy of Sciences Beijing 100101 China Qingheyan Gold Mine Qinglong County Hebei 066500 China

RECENTLY, a new type of gold deposits was discovered along the Great Wall in East Hebei Province, thatis the so-called ’Great Wall Type gold deposit’, a-kind of carbonate breccias with micro-disseminated(invisible) gold hosted in Middle-Proterozoic carbonate rocks. In the 30th IGC in August 1996 in Beijing, it was reported as the largest belt of Carlin-type gold deposits in China, and over 1 000 tons of goldreserves were estimated (oral report). Up to now, very little is known about its genesis. Our researchshows large differences between Great Wall type and Carlin-type gold. Most remarkable is that gold ishosted in carbonate breccias, to be precise, in cements (matrix) of breccias. Because of this, we consider the breccias as a key to understanding the genesis. In some unpublished reports, breccias were regarded as hydrothermal eruptive breccias, fractured breccias, sedimentary breccias, etc. The present

关键词： auriferous paleo-karstification C-O istopes.

large-scale cluster of gold deposits and metallogenesis in The eastern North China craton

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large-scale cluster of gold deposits and metallogenesis in T...

PROVENANCE AND TECTONIC SETTING OF THE PROTEROZOIC TURBIDITES IN HUNAN,SOUTH CHINA:GEOCHEMICAL EVIDENCE

中国科学院地质与地球物理研究所2002学术年会

作者： ZHAI Mingguo,YANG Jinhui,FAN Hongrui,MIAO Laicheng,LI Yonggang, Institute of Geology & Geophysics,The research center for mineral resources exploration,chinese academy of Sciences,Beijing,100029,China

The eastern North China craton contains the largest association of gold deposits in *** of gold deposits of different scales,commonly in groups or belts,constitute seven cluster *** contrast,there are no industrial gold deposits in the neighbouring areas to UHP Sulu region,and the northern Yangtze craton. The host rocks of the gold deposits are chiefly Precambrian high-grade metamorphic rocks and granites(anatectic melts derived from the Precambrian metamorphic rocks).Traditionally the gold deposits were considered to be of Archaean greenstone ***,recent geochronology of granitoid bodies and veins related to the gold mineralization and gold-bearing minerals in ore lodes reveals that the main metallogenic episode was at 110-130 Ma in all the seven cluster regions. Geochemical data also indicate that the metallogenic materials mainly came from the Precambrian basement of the North China craton and its underlying ***-Nb-Pb and S-O-H isotopic data of the ore lodes show crust-mantle mixing characteristics,corresponding to the metamorphic host rocks and basic-alkaline *** main structures controlling the mineralization are Mesozoic faults that trend～NE-NEE～***,the Precambrian rocks and Mesozoic magma-tectonic events provide the fundamental controls on the mineralization. Problematic relationships between the Mesozoic tectonic events(Yanshanian movements) and large-scale metallogenic activity have attracted substantial attention from chinese and foreign *** tectonic inversion in eastern China mainly involved a thick lithosphere that was thinning at depth and a reconstructed basin-and-range structure at the surface,which have been the result of a catastrophic lithosphere-asthenosphere *** tectonic event led to a large-scale mantle upwelling,which induced disturbance and adjustment of thermal,density and chemical phenomena,resulting in large scale crustal remelting(especially the lower crust),material exch

关键词： gold deposits metallogenesis eastern North China Mesozoic tectonic inversion

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PROVENANCE AND TECTONIC SETTING OF THE PROTEROZOIC TURBIDITE...

^(40)Ar-^(39)Ar thermochronology of two ductile shear zones from Yiwulüshan,West Liaoning Region: Age constraints on the Mesozoic tectonic events

中国科学院地质与地球物理研究所2002学术年会

作者： X.X.GU~(a,b,c),J.M.LIU~d,M.H.ZHENG~b,J.X.TANG~b,AND L.QI~a a.Institute of Geochemistry,chinese academy of Sciences,Guiyang,Guizhou 550002,P.R.China b.Department of resources and Economics,Chengdu University of Technology,Chengdu,Sichuan 610059,P.R. China c.Institute of mineralogy and Petrography,University of Innsbruck,Innrain 52,A-6020 Innsbruck,Austria d.research center for mineral resources exploration,chinese academy of Sciences,Beijing 100101,P.R.China

The geochemical composition of the Middle-Upper Proterozoic turbidites in Hunan, South China is related to provenance and tectonic setting of the sedimentary *** turbidites are characterized by moderate SiO2 contents(Al2O3/SiO2 typically 0.1-0.3) and moderate K2O/Na2O ratios(generally 0.1-0.3) but relatively high Fe2O3 1 MgO contents(5-10 wt%) and unusually low contents of CaO(typically,1 wt%).Abundances of ferromagnesian trace elements and incompatible elements are *** REE patterns are uniform and similar to the upper continental crust and typical post- Archean shales,with LREE enrichment,flat HREE, and significant negative *** general,the slates show higher contents of Fe2O3 1 MgO and ferromagnesian trace elements,and lower ratios of La/Sc and Th/Sc than the associated graywackes,suggesting that more mafic materials were incorporated into the clay-size fraction. Compared to the Upper Proterozoic Banxi Group,the Middle Proterozoic Lengjiaxi Group has higher concentrations for most ferromagnesian trace elements and lower La/Sc ratios,implying more mafic components in the provenance of the *** relationship among alkali and alkaline earth elements,the Chemical Index of Alteration(CIA),and the Th/U ratios indicate that the source area was affected by a moderate weathering *** main source was old continental crust(the Yangtze craton) dominated by felsic rocks of magmatic origin,with a variable admixture of mafic components from continental island arcs(e.g.,the Fangjingshan-Dayong and the Sibao-Yiyang island arc chains).The flysch deposition took place in a back arc basin,rather than a failed intracontinental rift as proposed by some *** suggest that suturing between the Yangtze and Cathaysia block did not occur until late Proterozoic time and that the final assembly of the supercontinent Rodinia in South China was probably marked by the Jingning orogeny at;0.8 Ga.

关键词：

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chinese Science Bulletin 2002年第13期47卷 1113-1118页

作者： ZHANG Xiaohui, LI Tiesheng & PU Zhipingresearch center of mineral resources exploration, Institute of Geology and Geophysics, chinese academy of Sciences, Beijing 100101, China Guangzhou Institute of Geochemistry, chinese academy of Sciences, Guangzhou 51 research center of mineral resources exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Two ductile shear zones trending EW and NNE respectively not only controlled the tectonic framework of the northern North China, but also constrained the geody-namic background for gold mineralization in this region. Field observations and microstructural analyses reveal that the EW trending ductile shear zones are mainly contributed to dextral compressional deformation resulting from top-to-the-southeast oblique thrust shearing, whereas the NNE trending ones are genetically related to sinistral strike-slip and extensional faulting. One sample from the former yielded an 40Ar-39Ar plateau age of (219±4) Ma (Bi) and two samples from the latter gave 40Ar-39Ar plateau ages of (116± 2) Ma (Bi) and (127±3) Ma (Bi). These ages provide constraints on the top-to-the-southeast oblique thrusting event occurring in Late Triassic and the sinistral extensional and strike-slip faulting event which occurred in Early Cretaceous.

关键词： 40Ar-39Ar age biotite ductile shear zone West Liaoning Region.

Rare Earth Elements in Manganese Nodules from the Central Pacific Ocean

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Acta Geologica Sinica(English Edition) 1992年第4期66卷 371-383页

作者： Guo Shiqin Sun Wenhong China Ocean mineral resources research and Developmetn Association Institute of mineral Deposits, chinese academy of Geological Sciences Liu Linqun China Ocean mineral resources research and Development Association China

Manganese nodules in areas CP and CC of the central Pacific are rich in REE. Comparatively speaking,the REE contents of nodules in area CP are hihger than those in area CC; and the REE contents of nodulesfrom seamounts are higher than those of nodules from sea-floor plains and hills. Within the nodules, the REEshow a zonal distribution. The REE distribution patterns of the nodules are similar to those of the sedimentsand have a mirror image relationship with those of the sea water. Trivalent REE were not obviously differenti-ated when they entered into the nodules from the sea water.A major factor causing the difference of REE abundances between nodules and sediments is the redoxconditions. The redox intensity of the ocean floor of the Pacific is controlled mainly by Antarctic Bottom Wat-er(AABW), The iron-bearing facies in the nodules is the main carrier of REE.

关键词： manganese nodule rare earth element Pacific