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chinese Science Bulletin 2002年第13期47卷 1119-1124页

作者： CHU Xuelei, SUN Min & ZHOU Meifuinstitute of geology and {2., chinese academy of sciences, Beijing {4., China Key Laboratory of Mineral Resources, institute of geology and {2., chinese academy of sciences, Beijing 100101, China Department institute of geology and {2. Chinese Academy of Sciences Beijing China Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Department of Earth sciences The University of Hong Kong Hong Kong China

By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle 1herzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

关键词： Da Hinggan area polymetallic deposit PGE pattern hypomagma.

Modeling the impact of Australian Plate drift on Southern Hemisphere climate and environment

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chinese Science Bulletin 2005年第14期50卷 1495-1502页

作者： ZHOU Botao1,5, ZHAO Ping2. JIAN Zhimin3 & HE Jinhai4.1. Nansen-Zhu International Research Center, institute of Atmospheric Physics, chinese academy of sciences, Beijing {2., China 2. institute of Climate and Environment, {4. academy of Meteoro- logical sciences, Beijing 100081, China 3. Laboratory of Marine geology, Tongji University, Shanghai 2.0092. China 4. Department of Atmospheric sciences, Nanjing institute of Meteorol- ogy, Nanjing 2.004., China 5. Graduate School of the chinese academy of sciences, Beijing 100039, China Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate School of the chinese academy of sciences Beijing 100039 China institute of Climate and Environment Chinese Academy of Meteorological Sciences Beijing 100081 China Laboratory of Marine geology Tongji University Shanghai 200092 China Department of Atmospheric sciences Nanjing Institute of Meteorology Nanjing 210044 China

Using a global atmosphere-ocean coupled model with the present-day and 14.MaB.P. oceanic topogra- phy respectively, two experiments are implemented to inves- tigate the effect of different locations of Australian Plate on the atmospheric circulation in middle-high latitudes of the Southern Hemisphere. The results show that when Austra- lian Plate lay south at 14.MaB.P., both anticyclone circula- tions in the subtropical oceans and cyclone circulation around 60°-70°S are strengthened. Subtropical highs and circumpolar low pressure appear stronger, which results in much stronger Antarctic Oscillation and shorter period of Antarctic Oscillation Index (AOI) at 14.MaB.P. The rainfall and the surface air temperature also change correspondingly. The precipitation decreases around 4.°S and increases around 60°-70°S, and the surface air temperature rises in high latitudes of the South Pacific and descends over the Weddell Sea and its north side. Besides, due to the changes of the temperatures and winds, Antarctic sea ice coverage also changes with its increasing in the Ross Sea and its west re- gions and decreasing in the Weddell Sea.

关键词：半球气候地球环球澳大利亚漂流物海洋地形学

Tectonic setting of the Helong Block:Implications for the northern boundary of the eastern North China Craton

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Science China Earth sciences 2005年第10期48卷 1599-1612页

作者： ZHANG Yanbin1, WU Fuyuan1, ZHAI Mingguo1 & LU Xiaoping1,2.1. institute of geology and {2.,{4., P.O. Box 982., Beijing {4., China 2. Regional Geological and Mineral Resources Survey of Jilin Province, Changchun 130062. China institute of geology and {2. chinese academy of sciences Beijing China Regional Geological and Mineral Resources Survey of Jilin Province Changchun China

LA-ICP-MS zircon U-Pb dating indicates that the Bailiping granitic pluton was em-placed during Late Paleozoic to Early Cretaceous (2.5―116 Ma) by four distinct magmatic epi-sodes, arguing against the previous thought that the Bailiping granites were emplaced during Archean, Proterozoic or Early Paleozoic. It is suggested that the so-called Archean Jincheng-dong granite-greenstone belt, mainly composed of Bailiping granites, should be broken down. Sr-Nd isotopic compositions of the Bailiping granites are similar to those of the Phanerozoic granites in the Xing’an-Mongolian orogenic belt, suggesting that their parental magmas were mainly derived from a juvenile crust with some contamination of ancient crustal materials during magma rising and/or emplacement. Therefore, the basement of the Helong Block is similar to that in the northern Xing’an-Mongolian Orogenic Belt, but different from that of the North China Craton. It is proposed that the Archean Jinchengdong complex in this area is probably an exotic slice from the North China Craton, which indicates that the Fu’erhe-Gudonghe Fault, located in northern part of the Helong area, is not the boundary between the North China Craton and the Xing’an-Mongolian Orogenic Belt. The possible boundary should be located further southward more than 50 km and near the Baitoushan volcano.

关键词： LA-ICPMS ziron U-Pb dating, Bailiping complex, Helong Block, North China Craton, Sr-Nd isotope.

Interactions between hotspots and the Southwest Indian Ridge during the last 90 Ma:Implications on the formation of oceanic plateaus and intra-plate seamounts

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Science China Earth sciences 2011年第8期54卷 1177-1188页

作者： ZHANG Tao 1,2.3,4.LIN Jian 5 & GAO JinYao 3,4.1 institute of Geodesy and geophysics,{2. {4. of {4.,Wuhan 4.0077,China 2.Graduate University of chinese academy of sciences,Beijing 10004.,China 3 The Second institute of Oceanography,State Oceanic Administrator,Hangzhou 310012.China 4.Key Laboratory of Submarine Geo{4.,State Oceanic Administrator,Hangzhou 310012.China 5 Department of geology and geophysics,Woods Hole Oceanographic Institution,Woods Hole,MA 02.4.,USA 1. institute of Geodesy and geophysics Chinese Academy of Sciences Wuhan 430077 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. The Second Institute of Oceanography State Oceanic Administrator Hangzhou 310012 China4. Key Laboratory of Submarine Geosciences State Oceanic Administrator Hangzhou 310012 China

This study investigates the relationship between the hotspot-ridge interaction and the formation of oceanic plateaus and seamounts in the Southwest Indian *** first calculated the relative distance between the Southwest Indian Ridge (SWIR) and relevant hotspots on the basis of models of plate reconstruction,and then calculated the corresponding excess magmatic anomalies of the hotspots on the basis of residual bathymetry and Airy *** results reveal that the activities of the Marion hotspot can be divided into three main phases:interaction with the paleo-Rodrigues triple junction (73.6-68.5 Ma),interaction with the SWIR (68.5-4.0}7 Ma),and intra-plate volcanism (4.0}7-0 Ma).These three phases correspond to the formation of the eastern,central,and western parts of the Del Cano Rise,*** magnitude and apparent periodicity of the magmatic volume flux of the Marion hotspot appear to be dominated by the hotspot-ridge *** periodicity of the Marion hotspot is about 2. Ma,which is much longer than that of the Hawaii and Iceland hotspots (about 15 Ma).

关键词： Southwest Indian Ocean hotspot-ridge interaction magmatic volume flux oceanic plateaus seamounts

Reinterpretation of the Guangxian Orogeny

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chinese Science Bulletin 2000年第13期45卷 1244-1248页

作者： WU Haoruoinstitute of geology and {2., chinese academy of sciences, Beijing {4., China institute of geology and {2. Chinese Academy of Sciences Beijing China

The Guangxian Orogeny, as an important concept on geology of South China, was created 70 years ago. It is generally regarded as an erogenic movement caused by the convergence of the Cathaysian and Yangtze blocks at the end of Silurian. Based on the recent progress of the geological research on Guangxi and adjacent areas, western Guangxi and Liuzhou-Heshan area of central Guangxi may belong to a stable block of Early Paleozoic. The Guangxian Orogeny originated from the northward translation of the Yunkai Block on its south at the end of Cambrian, and formed the Damingshan-Dayaoshan fold belt between the two blocks. It was possibly related with the Late Pan-African Orogeny. The convergence of the Cathaysian and Yangtze blocks occurred in Late Ordovician to Early Silurian and mainly had effect on Hunan and Jiangxi provinces. The term 'Chongyu Orogeny' may be suitable for it. At the end of Silurian orogenic movement did not occur in this area.

关键词： South China tectonics Paleozoic Guangxian Orogeny Yunan Orogeny Chongyu Orogeny.

Carbon isotope ratios of C_(4. plants in loess areas of North China

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Science China Earth sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2.3, HAN Jiamao 2. ZHOU Liping3, XIONG Xiaogang4. TAN Ming2. WU Zhenhai5 & PENG Jun6 1. Department of Plant Nutrition, China Agricultural University, Beijing 100094. China 2. institute of geology and geophysics,{4., Beijing {2., China 3. College of Environmental sciences, MOE Laboratory for Earth Surface Processes, Peking University, Beijing 100871, China 4. {4. of Botany,{4., Beijing 100093, China 5. Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712.00, China 6. Network Center, China Agricultural University, Beijing 100094. China 1. Department of Plant Nutrition China Agricultural University Beijing 100094 China 2. institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China 3. College of Environmental sciences MOE Laboratory for Earth Surface Processes Peking University Beijing 100871 China 4. institute of Botany Chinese Academy of Sciences Beijing 100093 China 5. Northwest Sci-Tech University of Agriculture and Forestry Yangling 712100 China 6. Network Center China Agricultural University Beijing 100094 China

Carbon isotope ratios (δ^(13)C) of 89 C_4.plant samples were determined fromthe loess area in North China. δ^(13)C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13)C values of C_4.plants show a slight decreasingtrend. The δ^(13)C values of C_4.plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3 species.

关键词： C4 plants, carbon isotope ratios, loess area.

Discovery of eclogite and its geological significance in Qiangtang area, central Tibet

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Science Bulletin 2006年第9期51卷 1095-1100页

作者： LI Cai1, ZHAI Qingguo2. DONG Yongsheng1 & HUANG Xiaopeng11. College of Earth sciences, Jilin University, Changchun 130061, China 2. institute of {2., chinese {4. of Geological sciences, Bei- jing 100037, China College of Earth sciences Jilin University Changchun 130061 China institute of geology Chinese Academy of Geological Sciences Beijing 100037 China

Eclogite is first discovered from Qiang- tang area, central Tibet, which occurs as a lens in the high-pressure metamorphic belt comprising glauco- phane-muscovite schist and garnet-muscovite schist, along the south margin of Lungmu Co-Shuanghu Paleo-Tethys suture. A glaucophane 4.Ar/39Ar age of 2.0 Ma and a phengite 4.Ar/39Ar age of 2.1.9 Ma have been obtained from blueschists associated with eclogite. The rock consists of garnet, omphacite, amphibole, phengite, and rutile, etc, and the jadeite content in omphacite ranges from 32.7% to 38.95%. It is estimated that the temperature of the eclogite is 2.35 GPa. The discovery of Qiangtang ecologite fur- ther supports that there is a suture zone of Indo- {4. epoch in central Qiangtang area, and is very important for discssing the evolution of the pa- leo-ocean and paleo-plate tectonics in this area.

关键词： Qianghai-Tibet Plateau Qiangtang eclogite tectonics.

No apparent lock-in depth of the Laschamp geomagnetic excursion: Evidence from the Malan loess

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Science China Earth sciences 2006年第9期49卷 960-967页

作者： ZHU Rixiang1, LIU Qingsong1,2. PAN Yongxin1, DENG Chenglong1, ZHANG Rui1 & WANG Xianfeng3 1. Paleomagnetism and Geochronology Laboratory (SKL of Lithosphere Evolution), institute of geology and {2., Chi- nese {4. of {4., Beijing 10002., China 2. institute of {2. and Planetary {2., University of California, Santa Cruz, CA 95064. USA 3. Department of geology and {2., University of Minnesota, Minneapolis, MN 554.5, USA 1. Paleomagnetism and Geochronology Laboratory (SKL of Lithosphere Evolution) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 2. institute of geophysics and Planetary geophysics University of California Santa Cruz CA 95064 USA 3. Department of geology and geophysics University of Minnesota Minneapolis MN 55455 USA

The first-order chronological framework of the long-term chinese loess/paleosol sequences was based mainly on magnetostratigraphy. However, there remain arguments on the lock-in ages of the major geomagnetic reversals. This study systematically compared the stratigraphic locations of the Laschamp excursion and Henrich events (H4.at～39 ka and H5 at～4. ka) recorded by the Luochuan loess profile in the central chinese Loess Plateau. Results show that the Lascchamp excursion is bracketed well by these two cold events, and the corresponding estimated age is between about 4..7-4..7 ka, which is close to the widely accepted age of ～4.-4. ka for the ***, our new results do not suggest apparent lock-in effects in the last glacial Malan loess.

关键词： chinese loess, Laschamp excursion, Henrich event, lock-in depth.

Project research of GIS data based on AutoCAD

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中国有色金属学会会刊：英文版 2005年第S1期15卷 244-246页

作者： YAO Xin ~(1, 2. (1. institute of geology and {2.,{4., Beijing {4., China 2. The Geomatics and Applications Laboratory, Liaoning Technical University, Fuxin 12.000, China) chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China Liaoning Tech Univ Geomat & Applicat Lab Fuxing 123000 Peoples R China

The digitalization software developed based on AutoCAD is one important platform of GIS data gather. But because AutoCAD itself is not the software of GIS, it can not be used to collect the attribute data. And conversion data to GIS software often lose some information such as color, line style, symbol shape. By using the XDATA, the Handle, the Group of AutoCAD and the provided ObjectArx to Redevelop, under AutoCAD condition, the attribute information collection with space information were realized, also did the AutoCAD symbol integrity and accurate expresses, then the demand of the digit graphics was satisfied.

关键词： AutoCAD attribute data data transfer ObjectArx XDATA

Geochemistry of high-Mg andesites from the early Cretaceous Yixian Formation, western Liaoning: Implications for lower crustal delamination and Sr/Y variations

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Science China Earth sciences 2006年第9期49卷 904-914页

作者： WANG Xiaorui1, GAO Shan1,2. LIU Xiaoming1, YUAN Honglin1, HU Zhaochu1, ZHANG Hong1,3 & WANG Xuance4.1. State Key Laboratory of Continental Dynamics, Department of geology, Northwest University, Xi`an 710069, China 2. State Key Laboratory of Geological Processes and Mineral Resources, China University of Geosciences, Wuhan 4.0074. China 3. Shenyang {2. of geology and Mineral Resources, Shenyang 110032. China 4. Guangzhou {2. of Geochemistry, chinese academy of sciences, Guangzhou 51064., China 1. State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi’an 710069 China 2. State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China 3. Shenyang institute of geology and Mineral Resources Shenyang 110032 China 4. Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

85 volcanic rocks of the Yixian Formation from the Sihetun type section werecollected and analyzed for geochemical and isotopic compositions. Major element compositionsindicate that the Sihetun volcanic rocks are high magnesium andesites with some basalts occurring atthe bottom of section. The Sihetun high magnesium andesites (SiO_2.= 52.82.59.31 wt%, Al_2._3=14.15-16.35wt%) show many characteristics of adakites such as depletion in heavy rare-earth elements(HREE; Yb = 1.03-1.88 μg/g) and Y(12.2. μg/g) and high Sr (62.-132. μg/g) and Sr/Y(32.88), withhigh La_N/Yb_N ratio (10-2.). They share similar major and trace element characteristics to volcanicrocks from the Xinglonggou Formation except their lower Nd isotope ratios (^(14.)Nd/^(14.)Nd(130Ma) = 0.5118-0.5119, ε_(Nd) (130Ma) = -11.6-13.8, ^(87)Sr/^(86)Sr (130 Ma) = *** were interpreted in a way that eclogite that formed at the base of thickened Archean lowercrust of the North China craton foundered into the convecting mantle and subsequently melted andinteracted with peridotite. However, compared to the Xinglonggou volcanic rocks, the source of theSihetun magma contained more ancient continental crustal material in order to explain its evolved Ndisotopes. The age of the Sihetun Formation was 12. to 130 Ma, and this indicates that delaminationlasted to the early Cretaceous period. The Sr contents and Sr/Y ratios of the Sihetun high-Mgandesites show significant negative correlations with SiO_2.for samples with SiO_2.> 56%. Thesesuggest that the Sr and Sr/Y values were reduced due to fractional crystallization of ***, the effect of crystallization on volcanic Sr and Sr/Y ratio has to be taken intoaccount.

关键词： High-Mg andesite, Adakite, Yixian Formation, North China Craton, delamination.