检索结果-南通市图书馆

chinese science Bulletin 1999年第S2期44卷 263-265页

作者： zhang Chengbo and zhang Zheru institute of geochemistry, chinese academy of sciences, guiyang 550002. china institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

1 Geological setting and occurrence features of the sediment-hosted gold deposits OVER 100 sediment-hosted gold deposits and occurrences of southwestern Guizhou lie near the sonthemedge of the Yangtze craton, which is composed of crystalline rocks of Proterozoic age, overlain mainly byPaleozoic and Lower to Middle Triassic shallow-marine platform and reef facies carbonates that gradesouthward and eastward into a thick section of interbedded siltstones and turbidite sandstones. Clasticdeposits were from the Yunkai Old Land and the Jiangnan Old Land respectively. The rocks were foldedand faulted during the Yanshanian orogeny, 190-65 ma ago. Mineral deposits were mainly located inthe breccia horizon at the base of the Longtan Formation of Upper Permian, underlain by the massive graylimestone of Lower Permian with a karst unconformity, and the high-angle fault zones in the Triassicargillaceous limestone interlayered with shale, arkose, and fine-grained turbidite sandstone. No

关键词： sediment-hosted gold deposits fossil hydrothermal system mathematical model.

Gold occurrence mechanism of fine disseminated gold deposits

在线全文

学校读者我要写书评

暂无评论

chinese science Bulletin 1999年第S2期44卷 18-20页

作者： WANG Xiaochun and zhang Zheru institute of geochemistry, chinese academy of sciences, guiyang 550002. china institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

THE fine disseminated gold deposits are widely distributed in the southwestern china and western UnitedStates. They have a mineral association of pyrite, arsenopyrite, marcasite, realgar, orpiment, stibnite,cinnabar, quartz, calcite and barite, and an element association of gold, arsenic, antimony, mercury,thallium and barium. Gold occurs as disseminated and in small size. This note aims to discuss the disseminated nature and micron size of the gold.

关键词： gold mechanism fine disseminated gold deposit.

Oxygen isotopic (^(17)O-^(18)O) heterogeneity in Archaean continental nucleus, North china Craton

在线全文

学校读者我要写书评

暂无评论

chinese science Bulletin 1999年第24期44卷 2267-2269页

作者： LIU Jianzhong, zhang Fuqin, LI Chunlai and WANG Shijie institute of geochemistry , chinese academy of sciences , guiyang 550002., china institute of Geophysics , chinese academy of sciences , Beijing 100101 , china institute of geochemistry Chinese Academy of Sciences Guiyang China institute of Geophysics Chinese Academy of Sciences Beijing China

The oxygen isotopic data for amphibolites from Archaean continental nucleus, North china Craton indicate that ( i ) the evolving lines structured by the data are parallel to the geoselenic evolving line, which means that the parent materials of these continental nucleus o-riginated from solar matter; ( ii ) different intercepts for these evolving lines manifest that oxy-

关键词： North china Craton oxygen isotope (I7O-18O ) heterogeneity.

Essential natures of Carlin-type gold mineralization in the Zhenxun Basin

在线全文

学校读者我要写书评

暂无评论

chinese science Bulletin 1999年第S2期44卷 238-240页

作者： ma jianqin~1 and zhang fuxin~2.1. institute of geochemistry, chinese academy of science, guiyang 550002. china Present address: Highway Egineer College, Xi’an Highway University, Xi’an 710064, china 2. Department of Geology, Northwest University, Xi’an, 710069, china institute of geochemistry Chinese Academy of Science Guiyang 550002 China Highway Egineer College Xi' an Highway University Xi' an 710064 China Department of Geology Northwest University Xi' an 710069 China

THE Zhen’ an-Xunyang (Zhen-Xun) Basin, located in the center of the Qinling Minor Plate in the Qinling orogen, develped and evoluted from the Devonian to the Triassic. The basin and its basement aresimilar to that of the southwestern part of the Yangtze Plate, where occur rich epithermal deposits. Thebasement of the basin is composed of the Proterozoic low-grade metamorphised volcanic and sedimentaryrocks, on which weakly metamorphised sedimentary and sedimentary rocks are deposited from the Cambrian to the Triassic. There occur three kinds of epithermal metal deposits: exhative-sedimentary-reformationtype Pb-Zn deposit (such as Xitonggou and Yuexi) ; reformation type Hg-Sb deposit (such as Dingjiashanand Shijiashan) ; sedimentary-reformation type Au deposit (such as Jinlongshan, Qiuling, Yaojie andJiashigou). The Au deposits are associated with minor Sb deposit. This contribution demonstrates onlythe essential natures of the epithermal gold mineralization.

关键词： Carlin type gold mineralization Zhenxun Basin.

Trace elemental behavior during chemical weathering: A case study of biotite-granitic weathering profile in Longnan, Jiangxi Province, china

在线全文

学校读者我要写书评

暂无评论

chinese science Bulletin 1999年第S2期44卷 130-132页

作者： ma Yingjun 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

THE study of chemical weathering processes can provide significant insight into not only the behavior ofmigration, deposition and accumulation of REEs and other elements (e.g. Au, Fe, Al ), but also themechanism of material cycle on the surface of the earth, especially the relationship between detrital sediments and provenance. Lateritic profiles are widespread in southern china, where two kinds of valuable supergene deposit occur. One is "ion-adsorbed" REE ore deposit; the other is lateritic gold ore deposit. This study is to investigate the mobility and fractionation of major and trace elements and mineralogical variations during chemical weathering of biotite granite in Longnan, Jiangxi Province, china, andto provide significant data for a better understanding of the relationships between weathering of

关键词： chemical weathering trace elements rare earth element fractionation biotite-granite.

Regularities controlling the distribution of halogens in the Danzhai epithermal Hg-Au deposit in Guizhou and their significance

在线全文

学校读者我要写书评

暂无评论

chinese science Bulletin 1999年第S2期44卷 146-148页

作者： zhang Qian, PAN Jiayong and SHAO Shuxun institute of geochemistry, chinese academy of sciences, guiyang 550002. china institute of geochemistry Chinese Academy of Sciences Guiyang 550002 China

HALOGENS, as mineralizer elements, have been attracting ever increasing attention of geological workers inpetrogenetically experimental and ore-forming fluid geochemical studies. However, little research workhas been done on the contents, variation characteristics and significance of halogens in solid ores(rocks). It is found in the study of the Danzhai Hg-Au deposit that (i) variations in the contents ofhalogens and their distribution regularities in solid rocks and ores can shed light on the formation of thedeposit; and (ii) halogens can serve the function of indicator elements in search of buried orebodies. 1 main characteristics of the ore

关键词： distribution regularity halogens Danzhai epithermal Hg-Au deposit Guizhou.

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

在线全文

学校读者我要写书评

暂无评论

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

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.

Some advancements in measurements of physical parameters of earth's material at high temperature and ultrahigh pressure

在线全文

学校读者我要写书评

暂无评论

chinese science Bulletin 1997年第21期42卷 1807-1810页

作者： XIE Hongsen, zhang Yueming, GUO Jie, XU Ji’an, SONG maoshuang, XU Yousheng and HOU Wei1. institute of geochemistry, chinese academy of sciences, guiyang 550002. china 2, institute of Earth science, Academia Sinica, Taipei, china institute of geochemistry Chinese Academy of Sciences Guiyang China institute of Earth science Academia Sinica Taipei China

IT is very important to measure physical parameters of minerals, rocks, melts and fluids athigh pressure and high temperature. The data from these experiments can provide materialsfor explanation of geophysical observations on large scale, and information of geochemicalfield. Therefore, we set up measurement methods on elastic wave velocity, electrical conduc-tivity and differential thermal analysis in YJ-3000 ton press fitted with a wedge-type

关键词： physical parameters earth’s material high temperature and nltrahigh pressure.

Bio-effects of REE and estimated daily intake allowance

在线全文

学校读者我要写书评

暂无评论

chinese science Bulletin 1999年第S2期44卷 102-104页

作者： zhang Hui, ZHU Weifang and FENG Jia State Key Latboratory 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

IT has become an urgent subject with the wider application of REE to study the effects of REE on environ- ment and human health. Some important REE toxicology data were obtained previously based on acuteand sub-chronic toxicity experiments on animals, but these results are indirect and suspectable becausethe REE compounds used in the experiments are different from those in food chains, and there still existsome uncertainties when the results are extrapolated from animals to human beings. This note focuses thebio-effects of REE on population from two typical REE-high areas in South Jiangxi, china, where theweathering crust-ion adsorbed-type REE ore deposits are widespread, and also on the estimation of dailyREE intake allowance in terms of REE contents and distribution in food chains. 1 Geologic setting and studying

关键词： rare earth elements bio-effects daily intake allowance South Jiangxi.

Tracer system on halogen mineralizer from the epithermal deposits in Guizhou Province

在线全文

学校读者我要写书评

暂无评论

chinese science Bulletin 1999年第S2期44卷 159-161页

作者： PAN Jiayong, zhang Qian and SHAO Shuxun Open Laboratory of Ore Deposit geochemistry, geochemistry of institute, chinese academy of sciences, guiyang 550002. china Open Laboratory of Ore Deposit geochemistry Geochemistry of Institute Chinese Academy of Sciences Guiyang 550002 China

HALOGENS are typical mineralizer elements and play a very important role in remobilization and resettlement of the ore-forming mental elements in the hydrothermal deposits. Studies of tracer system on halogens mineralizer include the following aspects: (i) halogens’ role as mineralizer in ore-forming action;(ii) halogens importance as tracer elements in formation and evolution of the epithermal ore deposit;(iii) halogens’ significance as guidance in looking for the buried orebodies. Guizhou is a concentrated area of epithermal Hg, Sb and Au deposits, where are distributed famousepithermal deposits such as the Wanshan Hg deposit, the Banpo Sb deposit, the Danzhai Hg-Au depositand the Lannigou Au deposit. many researches into geological and geochemical characteristics of thesedeposits have been done, but few study on halogen mineralizer.

关键词： tracer system halogens mineralizer epithermal deposits Guizhou.