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Independent ore deposits of dispersed elements

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Chinese Science Bulletin 1999年第S2期44卷 208-210页

作者： GAO Zhenmin, LI Chaoyang and YAO Linbo institute of geochemistry, Chinese {2. of sciences, guiyang 550002. china institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

EIGHT elements Ge, Ga, In, Tl, Re, Cd, Se and Te are usually referred to as dispersed elements. In the long past, there has been no report on independent ore deposits of dispersed elements at home andabroad. In recent years there have been continually discovered independent ore deposits of Ge, Tl, Cd,Se and Te in the southwestern part of china, which is a great breakthrough in the field of ore *** discovery of dispersed element independent deposits indicates that the dispersed elements are of dispersion in nature, but, on the other hand, they can also be concentrated to form independent ore depositsunder favorable geological conditions, even to form superlarge ore deposits under certain geological conditions. Having being restrained by traditional ideas, people have not paid sufficient attention to thestudy of independent ore deposits of dispersed elements as they have little knowledge about the geochemical behavior of dispersed elements in the processes of their mobilization, transport and enrichment.

关键词： dispersed element super-enrichment independent ore deposit existing form.

Experimental study on the interaction between peat,lignite and germanium-bearing solution at low temperature

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Science china Earth sciences 2005年第9期48卷 1411-1417页

作者： QI Huawen1,2. HU Ruizhong1 & QI Liang1 1. Key Laboratory of Ore Deposit geochemistry, Chinese academy of {2., guiyang 550002. china 2. Department of Earth Science, Nanjing University, Nanjing 2.0093, china Key Laboratory of Ore Deposit geochemistry Chinese Academy of Sciences Guiyang China Department of Earth Science Nanjing University Nanjing Chin

The interaction between peat, lignite and germanium(Ge)-bearing solution with an initial Ge concentration of 5 mg/L was studied at 2.―100℃ and at pH 2.96―12.08. The results show that the apparent transfer ratios of peat and lignite for Ge in the solution were positively correlated with temperature in acid environment (initial pH=2.96), and the ratios (up to 86.5%) of lignite were obviously higher than those (up to 58.5%) of peat, but the organic transfer ratios of lignite were lower than those of peat. The activation energy values for interaction between peat, lignite and Ge-bearing solution are 30.96 and 15.67 kJmol?1, respectively. The strong acid (initial pH=2.96) and the strong alkaline (initial pH=12.08) environment contribute to the transfer of Ge in the solution. At 4

关键词： low temperature, peat, lignite, Ge4+, complexation.

The hydrogeochemistry of the Wujiang River drainage system in Guizhou, china (Ⅱ)——Variations in concentrations of dissolved trace elements in karst river water and their controlling factors

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Chinese Science Bulletin 1999年第S2期44卷 112-115页

作者： LIU Congqiang and HAN Guilin State Key Laboratory of Environmental geochemistry, institute of geochemistry, Chinese academy of sciences, guiyang 550002. china State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

GEOCHEMICAL studies of trace elements, especially heavy metal elements in river water will provide thegrounds for the assessment of the influence of human activities on the environment. At present, the stud- ies of water bodies in karst areas are focussed on the analysis of chemical compositions of surface and underground water samples, and almost no systematic study has been done on trace elements. So theauthors have carried out systematic studies on the distribution of concentrations of the dissolved trace elements and their controlling factors, while some systematic studies are under way on the major compositionsof river water in the Wujiang drainage system in Guizhou Province. On the basis of the characteristics ofthe U-Ca-Sr system in river water and their geochemical indicating implications (Refer to the paper entitled "The hydrogeochemistry of the Wujiang River drainage system in Guizhou, china: I. The U-Ca-Srsystem in karst river water"), the paper is concerned mainly with the trace element composition of

关键词： dissolved trace elements karst Wujiang River drainage system Guizhou china.

Distribution and affecting factors of selenium in soil in the high-Se environment of Yutangba mini-landscape

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Chinese Science Bulletin 1999年第S2期44卷 46-48页

作者： ZHU Jianming and ZHENG Baoshan State Key Laboratory of Environmental geochemistry, institute of geochemistry, Chinese academy of sciences, guiyang 550002. china State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

SELENIUM is an indispensable trace element to human beings and normal animals but if found in excessively high dietary concentrations, it can cause poisoning. The most severe example of selenium poisoning occurred at Yutangba, a typical Se-rich area in china which is situated in the northern part of ShuangheTown about 81 km east of En’shi City of the southwestern Hubei Province and the only place in the worldwhere people suffered from selenosis. In this area selenium is present mainly in the carbonaceoussiliceous rocks and carbonaceous shales of the Upper Permian Maokou Formation 2.0 m north of the Yutangba area. Selenium concentrations in Se-rich carbonaceous siliceous rock samples collected byZheng and Song were estimated at 6 471 mg/kg and 8 390 mg/kg, respectively. However, Yang etal. once collected samples of stone coal in which the maximum Se concentration reached more

关键词： distribution affecting factors selenium soil Hubei.

Chemical-reaction-path modeling of ore-depositional processes in the Shangmanggang gold deposit, Yunnan, china

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Chinese Science Bulletin 1999年第S2期44卷 174-176页

作者： LI Zeqin, TU Guangchi and LI Chaoyang institute of geochemistry, Chinese {2. of sciences, guiyang 550002. china institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE Shangmanggang gold deposit is located at the southwestern corner of Yunnan, china. The deposit occurs along the southwest-trending Shangmanggang Fault. Near the surface, the hanging wall of the fault consists of sandstone and mudstone of the Middle Jurassic Mongga Formation (J2.), and also severs asthe hanging wall of the gold orebodies. The footwall of the fault is composed of dolomitite locally intercalated with medium-bedded limestone of Lower Permian Sazipo Formation (P1s). In the depth, the faultcut into strata of the Sazipo Formation (P1s). The deposit is characterized by intense clay alteration,which is similar to the Mercur Gold Deposit, Utah of USA, and by unique hydrothermal pinnacle karsl,

关键词： chemical-reaction-path modeling gold deposit Yunnan.

Geochemical characteristics of carbonate rock weathering and forming soil in the center area of Guizhou Province

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Chinese Science Bulletin 1999年第S2期44卷 218-219页

作者： SHAO Shuxun and YE Lin Open Laboratory of Ore Deposit geochemistry, institute of geochemistry, Chinese academy of sciences, guiyang 550002. china Open Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

ON the basis of the ecosystem characteristics of the carbonate rock area, the weathering of rock to formsoil is divided into 3 kinds of types: farm ecosystem, rainforest ecosystem and desert ecosystem in karstarea of central Guizhou. Carbonate rock weathering soil is dominant in the area, but there is a littleweathering soil of other rock in the farm ecosystem and rainforest ecosystem. The-carbonate rock weathering is the principal pattern to form soil in desert ecosystem. We measured contents of major chemical elements of rock and soil of weathering crust section, and referred to the previous researchs at home *** comparison with the chemical mean of soil of the weathering basalt of eastern chinaand the world, this note has obtained the law of elements migrating, dispersing and enriching duringcarbonate rock weathering in middle Guizhou.

关键词： carbonate rock weathering geochemical characteristics Guizhou.

Existing state of Cd in the Niujiaotang Cd-rich zinc deposit, Guizhou, china

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Chinese Science Bulletin 1999年第S2期44卷 182-185页

作者： YE Lin and LlU Tiegeng Open Laboratory of Ore Deposit geochemistry, institute of geochemistry, Chinese academy of sciences, guiyang 550002. china Open Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

As a dispersed element, cadmium is difficult to enrich and mineralize. As the Cd tetrahedron is similar tothat of Zn in covalent radius and crystal structure, both the elements possess similar geochemical *** is present mainly as isomorphous impurity in sphalerite. So Cd, as an associated element, occurslargely in Pb-Zn deposits. Current research both at home and abroad is focused on the environmental effect of Cd, but little work has been done on the mechanism of enrichment and mineralization of Cd. Theresearch papers available are mostly restricted to the ordinary geochemical characteristics of CdFrom the end of 1980s to the early 1990s, independent ore deposits of Te, Tl and other dispersed elements were discovered in the region of Southwest china. Prof. Tu Guangzhr proposed that dispersed elements can form their independent ore deposits. It has been realized that the dispersed

关键词： Cd Niujiaotang Cd-rich zinc deposit Guizhou.

Evolution of the upper earth crust in the southwest area of Yangtze terrain and its influence on the formation of Carlin-type Au ore deposits

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Chinese Science Bulletin 1999年第S2期44卷 220-221页

作者： CHEN Xiaozhong and LI Chaoyang Open Laboratory Laboratory of Ore geochemistry, institute of geochemistry, Chinese academy of sciences, guiyang 550002. china Open Laboratory Laboratory of Ore geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

1 Outline of the Yangtze terrain THE northwestern area of Sichuan and the joined area of Yunnan, Guizhou and Guangxi are the two majorfields where lots of Carlin-type Au ore deposits are located. Both of them belong to the western area ofYangtze terrain. The evolution of Yangtze terrain affected profoundly the geological evolution in these areas. Many epithermal ore deposits, such as Carlin-type gold, lead, zinc, mercury, stibium and arsenic,occur in the these areas, due to the evolution of crust in Yangtze terrain. The foundation of Yangtze terrain shows a structure of three stories, mainly composed of the Proterozoic clastic rocks and carbonic rocks that were involved in low-middle grade metamorphose. The meaningof the Yangtze terrain changed according to several geological times, which can be said that the activity ofYangtze terrain changed in the past. The Yangtze terrain undertook several processes of landmass hyper-

关键词： Yangtze terrain extending basin Carlin-type Au ore deposit.

Two-stage correlation between pH and REE concentration and pattern in rivers

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Chinese Science Bulletin 1999年第S2期44卷 106-107页

作者： WANG Zhongliang and LIU Congqiang State Key Laboratory of Environmental geochemistry, institute of geochemistry, Chinese academy of sciences, guiyang 550002. china State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

DUE to the unique chemical coherence and slight systematic difference properties, the REEs are extensively used as tracers for origin and evolution of the earth and its geology compositions （involved naturalwaters）. Soluble REE concentration in rivers is very low (10-12./sup>), and has a typical heavy REE enrichedpattern relative to the North American Shale Composite （NASC） than those of upper crust, suspendedmaterials and sediments. Negative Ce anomalies were widely observed in most of rivers. The behavior of REE in rivers can be affected by geology and chemical weathering of drainage basin,concentration and species of colloids and organs, major anions, pH, microbe action and so on. Especially pH is an important factor controlling the chemistry of water

关键词： rivers REE pattern pH two-stage correlation.