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Genetic relation between Carlin-type gold deposits and Sedex-type base metal mineralization

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chinese Science Bulletin 1999年第S2期44卷 207-208页

作者： LUO Taiyi and GAO Zhenmin Open Laborutory of Ore Deposit geochemistry, Institute of geochemistry, chinese academy of sciences,{3., china Open Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

GOLD mineralization and Sedex-type base metal mineralization (SBM) have been separately studied for along period. This may lead geologists to ignore the important exploration meaning of SBM in goldprospecting. A typical example is related to the Carlin-type gold ore deposits, in the study of which, Hg,As, Sb and other mineralizations have been stressed but SBM has been ignored. 1 A new phenomenon In recent years, it has been discovered that many Carlin-type gold ores and SBM are distributed inthe same geology unit but are disjunctive each other. In Carlin district of USA, Emsbo et *** reported the Sedex-type Pb-Zn orebody in thedepth of Meikle Au deposit, the same phenomenon has been described in Screamer, Golden April,

关键词： Carlin-type Au deposits Sedex-type mineralization genetic relation.

Chemical weathering crust: A long-term storage of elements and its implications for sediment provenance

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chinese Science Bulletin 1999年第S2期44卷 107-110页

作者： MA Yingjun and LIU Congqiang State Key Laboratory of Environmental geochemistry, Institute of geochemistry, chinese academy of sciences,{3., china State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

RAKE earth element (REE) and other trace element distributions in fine grained detrital sediments are widely used to characterize source composition of sediments, but ambiguities remain concerning theresponse of sediment composition (e.g. REEs) to provenance characteristics. One of the argumentsis whether significant amounts of REEs and other trace elements are likely to be stored in weathering profiles on the continents. Another ambiguity is which trace element ratios can be transferred with minimal changes from bedrock to weathering profiles and then to sediments. In addition, the effects oferosion and chemical weathering on the compositions of sediments remain poorly documented A major A major goal of this research is to investigate which elements are likely to be stored in weatheringprofiles, and to evaluate the effects of in situ chemical weathering and erosion on the compositions of siliciclastic sediments.

关键词： weathering profiles rare earth elements trace elemental ratios sediment provenance erosion.

Effects of fluids on migration of quartz——Experimental studies at low temperatures

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chinese Science Bulletin 1999年第S2期44卷 55-57页

作者： XIAO Huayun~(1,2), HUANG Zhilong~(1,2), LIU Congqiang~1, ZHU Jianming~1 and WU Xueyi~(1,2) 1. Institute of geochemistry, chinese academy of sciences, guiyang 550002,{3. 2. Open Laboratory of Ore Deposit geochemistry, chinese academy of sciences, guiyang 550002,{3. Institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China Open Laboratory of Ore Deposit geochemistry Chinese Academy of Sciences Guiyang 550002 China

QUARTZ is present mainly as the species H4SiO4 in fluid. The currently accepted values for quartz solubility at low temperatures are low. At 3.0℃, quartz solubility is about 600×10-6 in the quartz-fluid system. Therefore, the migration of quartz should not be evident at low temperatures. However, thepresent note shows that quartz can be enriched and migrate significantly at 3.0℃. The solid/fluid ratio（S/F） of the experiments is only about 10 g/mL.

关键词： fluid migration of quartz experimental studies low temperature.

The metallogenic epoch and ore-forming metal source of some large and superlarge deposits in Laojunshan, Yunnan——Evidence from Rb-Sr isotopic studies

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chinese Science Bulletin 1999年第S2期44卷 30-32页

作者： LIU Yuping~1, LI Chaoyang~1 and ZENG Zhigang~2 1. Institute of geochemistry, chinese academy of sciences, guiyang 550002,{3. 2. Institute of Oceanography, chinese academy of sciences, Qingdao 266071,{3. Institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China Institute of Oceanography Chinese Academy of Sciences Qingdao 266071 China

THE Laojunshan metallogenic district located in southeastern Yunnan is an important tin polymetallic metallogenic district in china. The Dulong (tin-zinc polymetal, superlarge), Xinzhai (tin, large) andNanyangtian (scheelite, large) are the main deposits in this district. These deposits outcrop in the Lower-Middle Cambrian metamorphic series, and most orebodies that associated with skarns closely are stratoid,lenticular in occurrence and in accordance with the wall rocks. Distributed around the Laojunshan granite, the above-mentioned deposits were considered to be of magmatic-hydrothermal origin. But

关键词： Rb-Sr isotopes metallogenic epoch source Yunan.

Metallogenic mechanisms of super-large Cu and Au deposits in the Dexing region and simulating experiments

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chinese Journal Of geochemistry 2010年第1期29卷 1-14页

作者： WU Xueyi and WANG Zijiang The State Key Laboratory of Ore Deposit geochemistry,Institute of geochemistry,chinese {3. of sciences,guiyang 55002,china The State Key Laboratory of Ore Deposit geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 55002 China

Based on the results of previous studies and under the direction of the theory of "ore deposit genesis",the authors made use of high temperature and high pressure experimental facilities and conditions at the Tectono-geochemistry Research Room under the State Key Laboratory of Ore Deposit geochemistry,Institute of geochemistry,{3. academy of sciences,and put the focus on the multi-source of tectonically controlling ore-forming materials,the characteristics of multi-stage and multi-episode hydrothermal activities and mineralization and the characteristics of multi-genesis and multi-ore deposition so as to shed light on the metallogenic mechanisms of super-large Cu and Au *** addition simulating experiments were made on multi-stage and multi-episode tectonic activities and rock and ore deformation,multi-stage and multi-episode tectonic activities and mobilization and migration of ore-forming materials,and multi-stage and multi-episode tectonic activities and superimposition and enrichment of ore-forming *** experimental results showed that under the action of multi-stage and multi-episode tectonic stress the deformation and fragmentation of not only rocks and ores have been intensified,and but also the ore-forming materials originally disbursed in the rocks and ores have been mobilized and migrated and superimposed and *** experimental results also provided the scientific experimental data and grounds for deep-going research on the rules of metallogenesis and geneses of super-large ore deposits in the Dexing region,Jiangxi Province.

关键词：成矿机制模拟实验德兴地区金矿床超大型构造地球化学成矿物质来源国家重点实验室

^(13.)Cs Redistribution in Thin Stony Soil of a Carbonate Rock Slope in Southwest china

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Pedosphere 2011年第1期21卷 37-45页

作者： LI Hao ZHANG Xin-Bao WANG Kc-Lin WEN An-Bang Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 (China) Graduate University Chinese Academy of Sciences Beijing 100049 (China) State Key Laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 (China) Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 (China)

The fallout radionuclide cesium-13.(13. Cs) has been widely employed as a tracer for assessment of soil loss from thick uniform soils;however,few studies have been conducted on thin stony soils on slopes underlain by carbonate rocks which are widely distributed in karst *** derived from 13. Cs measurement of soil samples collected along a carbonate rock slope with thin stony soil where neither soil erosion nor deposition occurred was used to investigate the characteristics of 13. Cs redistribution in a karst area of Southwest *** results indicated that the 13. Cs inventories of the surface soil on the slope studied were much lower than that of the local 13. Cs reference inventory and the 13. Cs activities were much higher than those on slopes with thick uniform *** spatial distribution of 13. Cs inventories was characterized by considerable *** high 13. Cs depletion in the stony soil of the slope studied was mainly because a considerable proportion of the fallout input of 13. Cs could be lost with runoff and the dissolution of carbonate particles in the soil promoted the loss of 13. *** demonstrated that the rates of soil loss could not be estimated from the degree of depletion of the 13. Cs inventory relative to the local reference inventory for the thin stony soil of the rocky slope underlain by carbonate rocks in the study area in the way that has been widely used in areas with thick uniform soils.

关键词： carbonate dissolution, ^13.Cs fallout, ^13.Cs inventory karst area runoff

Eclogites in the interior of the Tibetan Plateau and their geodynamic implications

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chinese Science Bulletin 2009年第15期54卷 2556-2567页

作者： ZHANG KaiJun1,2 & TANG XianChun2,3.1 Department of Earth sciences, Nanjing University, Nanjing 210093. china 2 Guangzhou Institute of geochemistry,{3., Guangzhou 510640, china 3.Graduate University of{3., Beijing 100049, china Department of Earth sciences Nanjing University Nanjing 210093 China Guangzhou Institute of geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate University of chinese academy of sciences Beijing 100049 China

Eclogites have been recently reported in the interior of the Tibetan Plateau, including in the central Qiangtang metamorphic belt, in the Basu metamorphic massif of the eastern Bangong-Nujiang suture zone, and at Songdo and Pengco in the eastern Lhasa terrane. Some typical ultrahigh-pressure (UHP) metamorphic phenomena, e.g., garnet exsolution from clinopyroxene, were documented in the Basu and Pengco eclogites. The UHP metamorphism in the interior of the Tibetan Plateau marked by these eclogites generally took place in the Early Mesozoic. Along with exhumation of these eclogites, (post-) collision-related magmatism extensively occurred around the central Qiangtang belt, the eastern Ban-gong-Nujiang suture zone, and the eastern Lhasa terrane. The occurrence of these Early Mesozoic ec-logites manifests an out-of-sequence evolution of the Tethys, and they could be a product of diachro-nous collision between the eastern Qiangtang terrane and the irregular continental margin of the united western Qiangtang-Lhasa plate, along the linked eastern Bangong-Nujiang-central Qiangtang zone. The collision-related magmatic rocks could have been originated from lithospheric thickening, melting, or detachment due to the collision. The presence of UHP metamorphic rocks in central Qiangtang and Basu implies likely continental deep-subduction, and the denudation of these two metamorphic zones could have served as the source of the Triassic turbidites in the Songpan-Garzê complex and the Ju-rassic turbidites in the western Bangong-Nujiang zone, respectively. However, studies of the eclogites in the interior of the Tibetan Plateau just began, and many principal aspects still remain to be explored, such as their distributions, typical lithologies and minerals, temperature-pressure conditions, timing of formation and exhumation, protoliths and tectonic setting, and relationship with the evolution of the Tethys and large-scale basins in Tibet.

关键词：地球动力学意义青藏高原榴辉岩

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural Science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2, PENG Shanchi~ 2,3., YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4, and GUO Qingjun~5(1. College of Resource and Environment of Guizhou University, guiyang 550003. china 2. Nanjing Institute of Geology and Palaeontology, chinese academy of sciences, Nanjing 210008, china 3. State Key Laboratory of Papaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Nanjing 210008, china 4. Department of Geological Science, Ohio State University, Columbus, OH 43.10, USA 5. Institute of geochemistry, chinese academy of sciences, guiyang 550002, china) College of Resource and Environment of Guizhou University Guiyang 550003 China Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological Science Ohio State University Columbus OH 43210 United States Institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, china and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2002, and O. indicus kobayashi Saito, 193., are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2003.is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12 segments, and a small pygidium that bears 2—3.axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3.and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962 or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou china.

Strong decays of N~*(153.) in an extended chiral quark model

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2,3.& ZOU BingSong1,2,3.1 Institute of High Energy Physics,chinese academy of sciences,Beijing 100049,{3. 2 Theoretical Physics Center for Science Facilities,chinese academy of sciences,Beijing 100049,{3. 3.Graduate University of chinese academy of sciences,Beijing 100049,{3. Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Graduate University of chinese academy of sciences Beijing 100049 China

The strong decays of the N*(153.) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(153.) contribute significantly to the N*(153.) → Nπ and N*(153.) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(153.) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(153.) strong decays five-quark components