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Acta Geologica Sinica(English Edition) 1991年第4期65卷 371-385,461页

作者： Huang Dianhao Ding Xiaoshi Wu Chengyu Zhang Changjiang institute of mineral Deposits, Chinese Academy of {2. Sciences, Beijing {2. Party No.3, Hebei Bureau of geology and mineral resources, Zhang jiakou, Hebei Fei Zhenbi institute of mineral Deposits Chinese Academy of Geological Sciences Beijing China

The deposit under study is a hydrothermal filling-metasomatic vein type lead-zinc-silver deposit, in whichgold and silver can be recovered as by-products. These metals mainly occur as microgranular native gold,electrum, stephanite, acanthite, pyraragyrite, freibergite, and native silver. Gold minerals tend to be associatedwith galenobismutite, native bismuth and unnamed Bi_2.e. They are either enclosed in pyrite, marmatite,iron-bearing sphalerite and galens or fill the microfissures of these minerals. Silver minerals usually occur incleavages or fissures of galena, marmatite and pyrite, but are not associated with gold and bismuth minerals.Gold and silver mineralizations occurred later than lead and zinc, while the silver mineralization was precededby that of gold.

关键词： mineralogy and Mode of Occurrence of Gold Hebei Province

DISCOVERY AND THE IMPLICATION OF A HYDROTHERMAL-METASOMATIC SKARN DEPOSIT IN GANGDISE TECTONIC ZONE,TIBET

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地学前缘 2000年第S1期7卷 143-144页

作者： Yao Peng 1,Li Jingao 2.WT5,5”BX](1 Chengdu institute of geology and {2. resources,Chengdu 610082.china 2.BGMR,Tibet,china)

Hydrothermal activity from a hydrothermal circulatory system is a special geological event, it is of importance to the formation of some massive sulfide deposits (hydrothermal deposits). The Authors think that Jiama polymetallic ore deposit in Gangdise tectonic zone, Tibet is a special skarn deposit i.e. a “hydrothermal\|metasomatic skarn deposit" bound up with benthonic hydrothermal circulatory system. Its important characteristics are as follows: 1 Evolution of the Gangdise island arc in studied area may be divided into three stages Middle Jurassic volcanic arc stage; Middle—Late Jurassic and Early Cretaceous inter arc sedimentary basin stage; and Eogene magmatic arc stage. The deposit is confined to the inter arc sedimentary basin. Existing data indicate that the volcanic arc provided Jiama deposit with abundant ore\|forming material; the inter arc sedimentary basin provided Jiama deposit with absolutely necessary space; the magmatic arc created reconcentration condition for the Jiama deposit.

关键词： skarn deposit hydrothermal circulatory system discovery implication

An approach to 3D NURBS modeling of complex fault network considering its historic tectonics

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Progress in Natural Science:Materials International 2006年第5期16卷 546-553页

作者： ZHONG Denghua, LIU Jie and LI Mingchao (School of Civil Engineering, tianjin University, tianjin 300072.{2.) School of Civil Engineering Tianjin University Tianjin 300072 China

Fault disposal is a research area that presents difficulties in 3D geological modeling and visualization. In this paper, we propose an integrated approach to reconstructing a complex fault network (CFN). Based on the non-uniform rational B-spline (NURBS) techniques, fault surface was constructed, reflecting the regulation of its spatial tendency, and correlative surfaces were enclosed to form a fault body model. Based on these models and considering their historic tectonics, a method was put forward to settle the 3D modeling problem when the intersection of two faults in CFN induced the change of their relative positions. First, according to the relationships of intersection obtained from geological interpretation, we introduced the topological sort to determine the order of fault body construction and rebuilt fault bodies in terms of the order; then, with the disposal method of two intersectant faults in 3D modeling and applying the Boolean operation, we investigated the characteristic of faults at the intersectant part. An example of its application in hydropower engineering project was proposed. Its results show that this modeling approach can increase the computing efficiency while less computer memory is required, and it can also factually and objectively reproduce the CFN in the engineering region, which establishes a theoretical basis for 3D modeling and analysis of complex engineering {2..

关键词： fault network NURBS technique historic tectonics topological sort 3D modeling.

THE PATTERN OF GENERAL ATMOSPHERIC CIRCULATION IN EASTERN ASIA BEFORE THE UPLIFT OF THE TIBETAN PLATEAU

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地学前缘 2000年第S1期7卷 399-400页

作者： Jiang Xinsheng, Pan Zhongxi, Fu Qingping (Chengdu institute of geology and {2. resources,Chinese Academy of geological Sciences, Chengdu 610082., china)

The global climatic change study is a hot point *** the pattern of the general circulation of the atmosphere is the key factor for climate,the reconstruction of the pattern of the past general circulation of the atmosphere has become important part of the global climatic change *** paleowind belts are the comprising part of the past general circulation of the atmosphere and also the records of the circulation,therefore,their reconstruction will be helpful to the reconstruction of the general circulation of the *** present years,the pattern of the general circulation of the atmosphere has attracted great concern from *** example,Zhang Linyuan and Liu Dongsheng, based on the existence and inexistence of the Tibetan Plateau and paleogeography,divide the evolution of the general circulation of the atmosphere in eastern asia into two stages:the planetary wind stage before the uplift of the plateau and the monsoon stage after the uplift of the plateau which is subdivided into ancient monsoon and modern monsoon *** Dong Guangrong et al., Jiang Xinsheng et al. and Cooke et al, based on the latitudinal distribution of the Cretaceous and Tertiary deserts and the generation of arid climate,suggest that there was a subtropical high pressure zone across the eastern asia and was a planetary wind system,but have not found any direct record of the *** is true that before the Early Tertiary,not only organism, but also inorganism,i.e.,biogeography and lithogeography, show strong zonal *** can only indicate that zonal climate was evident at that *** course, as the climate is the result of the influences on the ground by zones of the circulation,it is reasonable to deduce the existence of zonal circulation,i.e. the the existence of the planetary wind system,from the zonal *** it would be much better if direct record of planetary wind system were *** winds are the main geological agent for a desert

关键词： Cretaceous deserts regularity of paleowind directions pat tern of paleowind belts uplift of the Tibet Plateau

Types, Metallogenic Environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in china

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Acta Geologica Sinica(English Edition) 1989年第1期63卷 79-92页

作者： Wang Zhitian and Qin Kezhang Beijing institute of geology for {2. resources, CNNC, Beijing Zhang Zhongmin Beijing institute of geology for {2. resources CNNC Beijing

Based upon a comprehensive study of 12. copper deposits in china. this paper reaches the following conclusions: 1. The crust in china was solidified pretty late; with the accretion of the plate, the copper {2.ization moved towards its margin in space and became successively younger in age. 2. The major copper ore types ever found in the world have mostly been discovered in china, in which the porphyry type seems to be the most important and the massive sulfide type in the transitional bed between marine clastic and carbonate rocks is clearly defined. 3. Carbonate strata are widespread in china and their deposition lasted for a long geological period, so the proportion of copper deposits occurring in them is large as compared with other parts of the world. 4. Seven metallogenic epochs can be recognized, in which the Mesozoic one plays the leading role and the middle(late) Palaeozoic and Cenozoic ones are next in importance. {2.ization was comparatively simple in the early geological period. and became diversified later on. In the early epochs copper deposits related to basaltic magmatism and metamorphosed marine sediments predominated, whereas in the later epochs those related to granitic magmatism and continental sedimentation were dominant. 5. There exist in china thirteen metallogenic provinces, of which the Lower Yangtze downwarping belt, Sanjiang fold system, Jiangnan axis and Xikang-Yunnan axis are of greater significance. 6. The crustal mobility in china was rather pronounced, the polycyclic evolution of the crust has resulted in such obvious phenomena as the inheritance of {2.ization, the coexistence of various types and the superposition of different genetic types.

关键词： Metallogenic Environments and Characteristics of Temporal and Spatial Distribution of Copper Deposits in china Types

The features of gravity field and deep structure in western part of the South Yellow Sea

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Chinese Science Bulletin 2000年第8期45卷 759-764页

作者： WANG Qianshen1 & AN Yulin1. institute of Geophysics, Chinese Academy of Sciences, Beijing 100101, china 2. Chinese University of {2., Beijing 100083, china institute of Geophysics Chinesc Academy of Sciences Beijing China Chinese University of geology Beijing China

The gravity data from the sea region to the west of 12.° E of the South Yellow Sea have been processed and the feature of gravity fields analyzed. An experience relationship formula on the filter wavelength and corresponding depth has been put forward. Combined with the geological and seismic data, the deep tectonic framework and structural characters as well as possible favourable prospecting district for hydrocarbon in the South Yellow Sea have been discussed and analyzed.

关键词： western part of the South Yellow Sea gravity field deep structure.

SHRIMP zircon U-Pb age and Nd isotopic study on the Nyainqêntanglha Group in Tibet

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Science china Earth Sciences 2005年第9期48卷 1377-1386页

作者： HU Daogong1, WU Zhenhan1, JIANG Wan1, SHI Yuruo2. YE Peisheng1 & LIU Qisheng1 1. institute of Geomechanics, Chinese Academy of geological Sciences, Beijing 100081,{2. 2. institute of geology, Chinese Academy of geological Sciences, Beijing SHRIMP Centre, Beijing 100037,{2. institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of geology Chinese Academy of Geological Sciences Beijing SHRIMP Centre Beijing China

The Nyainqêntanglha Group is traditionally viewed as the oldest metamorphic basement in the Lhasa block, but its formation age and tectonic setting remain debate. Zircons extracted from the metamorphic sequence of volcanics and intrusions of the Nyainqêntanglha Group, 10 km west of Nam Co in northern Lhasa block, have been investigated by cathodolu- minescence (CL), backscattered (BSE) and dated by ion microprobe (SHRIMP). We conclude that the U-Pb age of 787±9 Ma of zircons from the trondhjemite imposes a constraint on maxi- mum protolith age, and minimum formation age of the Nyainqêntanglha Group is constrained by U-Pb age of 748±8 Ma of zircons from the granite. The formation age of the Nyainqêntanglha Group is consistent with sedimentary age of Greater Himalayan rocks, showing that they devel- oped coevally in an arc-basin tectonic setting of Neoproterozoic active continental margin along the northern margin of the India shield. The inherited zircons from the tholetiite and granite give older 2.7Pb/2.6Pb ages from 947 to 1766 Ma. The positive εNd( t ) value indicates that the mafic rocks were derived from the depleted mantle, but contaminated by the older continental crustal material. Integrated Nd model age and U-Pb age data provide excellent evidence for the exis- tence of Mesoproterozoic basement in the Lhasa block during Neoproterozoic time.

关键词： Nyainqêntanglha Group, SHRIMP dating, Nd isotope, Neoproterozoic, Tibet.

Geochemical characteristics of the independent cadmium deposit, Niujiaotang, Duyun, Guizhou

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Chinese Science Bulletin 1999年第S2期44卷 61-63页

作者： LIU Tiegeng~1, YE Lin~1 and CHEN Guoyong~2.1. institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. china 2. Team No. 104, Bureau of {2. and mineral resources, Duyun, Guizhou 558000, china institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Team No. 104 Bureau of Geology and Mineral Resources Duyun Guizhou 558000 China

A large independent cadmium deposit has been found at Niujiaotang, Duyun, in recent years. To the bestof our knowledge this represents the first case of its kind in the world. With a reserve of over 5 000 tonsof cadmium, the deposit is unique in its high concentrations of cadmium which are tens of to over onehundred times higher than in ordinary cadmium mineralizations associated with Pb-Zn deposits. 1 geological characteristics The Niujiaotang deposit is located at the southwest margin of the Yangtze Plate. The region consistsof a thick sedimentary cover ranging from Sinian to Triassic in age overlying unconformably the basementof Mid-Proterozoic metamorphosed volcanic-sedimentary rocks. Lower Cambrian carbonate strata arcoutcropped in the mining district. Cadmium mineralizations, with seven layers recognizable, are devel-

关键词： independent cadmium deposit mode of occurrence of cadmium inclusion fluid feature stable isotope geochemistry.

Discovery of the budding phosphatized globular fossils from the Neoproterozoic Doushantuo Formation at Weng'an, Guizhou Province, china

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Progress in Natural Science:Materials International 2006年第10期16卷 1079-1083页

作者： LIU Pengju , YIN Chongyu and TANG Feng (institute of geology, Chinese Academy of {2. Sciences, Beijing 100037, china) institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

There is much debate on biological affinities of the phosphatized globular fossils from the Neoproterozoic Doushantuo phosphorites at Weng’an, Guizhou Province. Here we report for the first time the budding structures of some of these globular fossils, which have previously been interpreted as the resting eggs and early cleavage embryos of metazoans. The budding structures are similar to the germinating tubes of the spore and zygote of living algae, suggesting that some globular fossils from the Doushantuo phosphorites bear affinity with algae. The present new information indicated various biological affinity of the phosphatized globular fossils from the Doushantuo phosphorites.

关键词： Neoproterozoic Donshantuo Formation globular fossil budding structure algae resting eggs embryos.

Dehydration melting of solid amphibolite at 2.0 GPa: Effects of time and temperature

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Science china Earth Sciences 2005年第8期48卷 1120-1133页

作者： ZHOU Wenge1, XIE Hongsen1, LIU Yonggang1, ZHENG Xiaogang1, ZHAO Zhidan2.& ZHOU Hui3 1. Laboratory of Material in the Earth’s Interior, institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002. china 2. Department of {2., china University of Geosciences, Beijing 100083, china 3. Department of {2., Peking University, Beijing 100871, china Laboratory of Material in the Earth’s Interior Institute of Geochemistry Chinese Academy of Sciences Guiyang China Department of geology China University of Geosciences Beijing China Department of geology Peking University Beijing China

Two sets of dehydration-melting with a natural solid amphibolite, collected from North Himalayan structure zone, Tibet, have been carried out in multi-anvil apparatus at 2.0 GPa and 800―1000℃, for 12.2.0 h. One is keeping the pressure at 2.0 GPa and the annealing time of 12.h, changing the temperature (800―1000℃). The other is keeping the pressure at 2.0 GPa and temperature at 850℃, varying the annealing time (12.2.0 h). The products are inspected with microscope and electron probe. The results indicate that at 2.0 GPa, annealing time of 12.h, garnets, melts and clinopyroxenes occur in amphibolite gradually with increasing temperature and the chemical compositions of melt vary from tonalite to granodiorite, and then to tonalite. However, at 2.0 GPa and 850℃, with the annealing time increasing, the garnets, melts and cli-nopyroxenes also occur in amphibolite gradually and the chemical compositions of melt vary from tonalite to granodiorite. In both cases, melts interconnect with each other when the contents of melt are over the 5 vol.%. the viscosities of the melt produced in amphibolite at temperature higher than 850℃ are on a level with 104 Pa·s. The interconnected melt with such a viscosity may segregate from the source rock and form the magma over reasonable geological time. Therefore, it is believed that at the lower part of the overthickened crust, the tonlitic and grano-dioritic magma may be generated through the dehydration melting of amphibolite.

关键词： solid amphibolite, high pressure, high temperature, time, partial melting.