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Ultrahigh pressure (>7 GPa) gneissic K-feldspar (-bearing) garnet clinopyroxenite in the Altyn Tagh, NW china: Evi- dence from clinopyroxene exsolution in garnet

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science china {2. sciences 2005年第7期48卷 1000-1010页

作者： LIU Liang1,3, CHEN Danling1, ZHANG Anda1, SUN Yong1, WANG Yan1, YANG Jiaxi1,2.& LUO Jinhai1 1. Key Laboratory of Continental Dynamics of the Ministry of Education of china, Northwest University, xi’an 710069, china {2., Chang’an University, xi’an 710054. china 3. The Laboratory of Orogen and Basin of the Ministry of Education, Peking University, Beijing 100871, china Key Laboratory of Continental Dynamics Ministry of Education of China Northwest University Xi'an 710069 China Laboratory of Orogen and Basin Ministry of Education Peking University Beijing 100871 China college of earth {2. and land resources Chang'an University Xi'an 710054 China

The exsolution of clinopyroxene and rutile in coarse-grain garnet is found in the gneissic K-feldspar(-bearing) garnet clinopyroxenite from Yinggelisayi in the Altyn Tagh, NW china. The maximum content of the exsolved clinopyroxene in the garnet is up to >5% by volume. The reconstructed precursor garnet (Grt1) before exsolution has a maximum Si content of 3.061 per formula uint, being of supersilicic or majoritic garnet. The peak-stage metamorphic pressure of >7 GPa is estimated using the geobarometer for volume percentage of exsolved pyroxene in garnet and the Si-(Al+Cr) geobarometer for majoritic garnet, and the temperature of about 1000℃ using the ternary alkali-feldspar geothermometer and the experimental data of ilmen- ite-magnetite solid solution. The protoliths of the rocks are intra-plate basic and intermediate ig- neous rocks, of which the geochemical features indicate that they are probably the products of the evolution of basic magma deriving from the continental lithosphere mantle. The rocks are in outcrops associated with ultrahigh pressure garnet-bearing lherzolite and ultrahigh pressure garnet granitoid gneiss. All of these data suggest that the ultrahigh pressure metamorphic rocks in the Altyn Tagh are the products of deep-subduction of the continental crust, and such deep- subduction probably reaches to >2.0 km in depth. This may provide new evidence for further discussion of the dynamic mechanism of the formation and evolvement of the Altyn Tagh and the other collision orogenic belts in western china.

关键词： Altyn Tagh gneissic K-feldspar (-bearing) garnet clinopyroxenite clinopyroxene exsolution in garnet ultra-high pressure metamorphism.

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Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4, LEI Wei-wei1, 2. GUO Zeng-zhang1, 2. WU Li-xin3, ZHANG Qin4 1. School of Survey and land Information Engineering, Henan Polytechnic University, Jiaozuo 454003, china 2. Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping, Henan Polytechnic University, Jiaozuo 454003, china 3. college of resources and Civil Engineering, Northeastern University, Shenyang 110819, china 4. college of Geology Engineering and Geomatics, Chang’an University, xi’an 710054. china [a] School of Survey and land Information Engineering Henan Polytechnic University Jiaozuo 454003 China [b] Key Laboratory of Mine Spatial Information Technologies of State Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China [c] college of resources and Civil Engineering Northeastern University Shenyang 110819 China [d] college of Geology Engineering and Geomatics Chang'an University Xi'an 710054 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

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Constraints of authigenic carbonates on trace elements (Sr,Mg) of lacustrine ostracod shells in paleoenviron-ment reconstruction and its mechanism

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science china {2. sciences 2008年第5期51卷 654-664页

作者： HU Guang1,2. JIN ZhangDong1 & ZHANG Fei3 1 State Key Laboratory of Loess and Quaternary Geology, Institute of earth Environment, Chinese Academy of sciences, xi’an 710075, {2. 2.Graduate University of the Chinese Academy of sciences, Beijing 100049, {2. 3 college of resources and Environmental science, Nanjing Agricultural University, Nanjing 2.0095, {2. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China Graduate University of the Chinese Academy of sciences Beijing 100049 China college of resources and Env

Molar ratios of Mg/Ca and Sr/Ca were measured in two species of ostracod shells preserved in the upper core (15–55 m) of the Hequing Basin in Yunnan Province, southwest china. By correlating the molar ratios between Mg/Ca and Sr/Ca and comparing them with Sr concentrations of the sediments, we suggested that: (1) the molar Mg/Ca and Sr/Ca ratio variations in respective ostracod primo reflected the changes in its ambient water composition and ecology; (2. the molar Sr/Ca ratios responded better to the salinity change linearly than Mg/Ca without aragonite precipitation in the system, and otherwise there was no linear relation between them; and (3) the molar Sr/Ca ratios were mainly controlled by salinity and authigenic carbonate precipitation, whereas the molar Mg/Ca ratios were related to both salinity and temperature. In fact, the rate of ostracod growth owing to temperature controls the fluctuation of Mg/Ca in shells. Here, more attentions should be paid to the constraint of authigenic mineral precipitation processes on the trace elements in ostracod shells and to the correlation between these trace elements in biogenic carbonates and compositions of the sediments in systems and in future in vitro experiments.

关键词： ostracod shell molar Sr/Ca ratio molar Mg/Ca ratio environmental response Heqing Basin

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The δ^(18)O variation of a stalagmite from Qixing Cave,Guizhou Province and indi-cated climate change during the Holocene

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Chinese science Bulletin 2001年第22期46卷 1904-1908页

作者： CAI Yanjun, ZHANG Meiliang, PENG Zicheng, LIN Yushi, AN Zhisheng, ZHANG Zhaofeng & CAO YunningState Key Laboratory of Loess and Quaternary Geology, Institute of earth Environment, Chinese Academy of sciences,{2. Karst Dynamics Laboratory, Ministry of land and resources, Guilin 541003, china Department of earth and Space science, University of science & Technology of china, Hefei 2.002., china State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an China Karst Dynamics Laboratory Ministry of Land and Resources Guilin China Department of earth and Space science University of Science & Technology of China Hefei China

A stalagmite from Qixing Cave, Guizhou Province was dated with the TIMS U-series method and its oxygen isotope composition was analyzed. On the basis of the ages and the variations of the δ18O of the stalagmite, the climate change of the last 7.7 ka has been reconstructed in this area: 7.7-5.8 ka, summer monsoon maximum period; 5.8-3.8 ka summer monsoon weakening period; 3.8-0.15 ka, weakened summer monsoon and high amplitude climate fluctuations period. We put forward that the increasing trend of δ18O of the stalagmite reflected not only the weakening of the summer monsoon, which was caused by the decreasing of solar radiation in the Northern Hemisphere, but also the possibly decreasing contribution of the southwest monsoon to the rainfall of this area. These results are consistent with the output of the numerical climate-model modeling. The high amplitude fluctuation of the δ18O may imply the quick shift of the contributions of different moisture sources to the precipitation in this area.

关键词： stalagmite Holocene southwest monsoon.

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Seismic geomorphology of buried channel systems in the western South Huanghai Sea:retrodiction for paleo-environments

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Acta Oceanologica Sinica 2011年第1期30卷 47-58页

作者： KONG xianghuai LIU Jian DU Yuansheng WEN Chun XU Gang Faculty of earth sciences China University of Geosciences Wuhan 430074 China Qindao Institute of Marine Geology Ministry of Land and Resources Qingdao 266071 China Key Laboratory of Marine Hydrocarbon resources and Environment Geology of Ministry ofland and resources Qingdao 266071 China college of Marine Geo-science Ocean University of China Qingdao 266100 China

Quantitative morphologic analysis of shallowly buried, dendritic channel systems in the continental shelf off the abandoned Huanghe River （Yellow River） mouth has been made based on interpretation of high resolution seismic profiles, with the attempt to estimate the paleo-hydrologic parameters when the incised-channels formed, then assess the paleoenvironment. The results indicate that the buried channel systems were formed about 44 cal ka BP when the shelf was subaerially exposed and subsequently drowned and filled during the Holocene transgression with the sea level rise continuously. The study area has experienced the processes from fluvial and estuarine to fully marine.

关键词： South Huanghai Sea (Yellow Sea) seismic geomorphology buried paleochannels,paleoenvironment

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land cover changes based on plant successions: Deforestation, rehabilitation and degeneration of forest in the upper Dadu River watershed

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science china {2. sciences 2005年第12期48卷 2214-2230页

作者： YAN Jianzhong1,2.3, ZHANG Yili1, BAI Wanqi1, LIU Yanhua4, BAO Weikai5, LIU Linshan1, 2.& ZHENG Du1 1. Institute of Geographic sciences and Natural resources Research, Chinese Academy of sciences, Beijing 100101, china 2. Graduate School of the Chinese Academy of sciences, Beijing 100039, china 3. college of resources and Environment, Southwest Agricultural University, Chongqing 400716, china 4. The Ministry of science and Technology, P. C. china, Beijing 100862. china 5. Chengdu Institute of Biology, Chinese Academy of sciences, Chengdu 610041, china 1. Institute of Geographic sciences and Natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate School of the Chinese Academy of sciences 100039 Beijing China 3. college of resources and Environment Southwest Agricultural University 400716 Chongqing China 4. The Ministry of science and Technology P. C. China 100862 Beijing China 5. Chengdu Institute of Biology Chinese Academy of Sciences 610041 Chengdu China

To link regional land use/cover changes with environmental effects, land cover changes are required to reflect vegetation successions, whereas the land cover classification systems commonly used nowadays cannot serve this purpose. In this paper, a new land cover classification system is established in which land covers are classified by the vegetation succes-sions, taking Zamtang County, Barkam County and Jinchuan County in the upper Dadu River watershed as a study area. Using multi-temporal remote sensing images, the land cover data of 1967, 1986 and 2.00 are obtained by means of integration of unsupervised classification and visual interpretation methods. The database facilitates the study of land use/cover changes, en-vironmental effects and ecological construction. land cover changes reflect the main ecological processes in the upper Dadu River watershed. The landscape composed mainly of grasslands, wildwoods and alpine scrubs in 1967 was changed to that of grasslands, secondary forests, al-pine scrubs, fragmentary wildwoods, artificial forests, secondary scrubs in 2.00, meanwhile, the landscape got more fragmentized. The total area of the forests decreased by 9.43%. Study results have shown the process of restoration of logged areas in forest centers. From 1967 to 2.00, only 6.86 percents of logged areas were converted to shrubs, meadows or crop-lands, and the rest were converted into artificial forests or secondary forests. So the ecological shelter functions will be restored, stage by stage. Firewood collection, charcoal production and overgrazing are the three major triggers for the extensive degradation of alpine oak forests, Sa-bina tibetica forests and meadows. The arid valley grasslands expanded too. The degradation of vegetation in the southern slopes impairs ecological shelter functions and affects livelihood of local residents, so it is essential to find effective measures for ecological restoration and recon-struction. Field investigations have found

关键词： land use/cover classification, upper Dadu River watershed, vegetation successions, GIS, RS.

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Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the xiangxi Bay

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science china(Technological sciences) 2010年第4期53卷 1114-1125页

作者： YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2.& xiAO ShangBin1,3 1 college of Civil & Hydroelectric Engineering,china Three Gorges University,Yichang 443002.china 2.School of Water resources & Hydropower Engineering,Wuhan University,Wuhan 430072.china 3 Institute of earth Environment,Chinese Academy of sciences,xi’an 710075,china 1. college of Civil & Hydroelectric Engineering China Three Gorges University Yichang 443002 China2. School of Water Resources & Hydropower Engineering Wuhan University Wuhan 430072 China3. Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China

The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,*** hydrodynamic parameters and water quality parameters(*** velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 *** water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different *** water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding ***,the water stability index in the mainstream remained small but it was lowered in the *** main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding *** grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the ***,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.

关键词： impounding density current eutrophication the xiangxi Bay the Three Gorges Reservoir

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Monitoring Dynamic Change of land Cover Based on SVM and Satellite Images in Hanoi,Vietnam

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Wuhan University Journal of Natural sciences 2010年第4期15卷 355-362页

作者： ZHAO Jinling1,2. LIU Chuang1, 3 1. Institute of Geographic sciences and Natural resources Research, Chinese Academy of sciences, Beijing 100101, china 2. Graduate University of Chinese Academy of sciences, Beijing 100049, china 3. college of resources science and Technology, Beijing Normal University, Beijing 100875, china Institute of Geographic sciences and Natural resources Research Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of sciences Beijing China college of resources {2. and Technology Beijing Normal University Beijing China

An integral method,combining support vector ma-chine (SVM) with remote-sensing analysis techniques,was ex-plored to monitor Hanoi’s dynamic change of land cover. The landsat thematic mapper (TM) image in 1993,the enhanced the-matic mapper plus (ETM+) image in 2.00,and the image with the charge-coupled device camera (CCD) on the {2.-Brazil earth resources satellite (CBERS) in 2.08 were used. Six land-cover types,including built-up areas,woodland,cropland,sand,water body and unused land,were identified. The detected results showed visually the rapid urban expansion as well as land-cover change of Hanoi from 1993 to 2.08. There were 12.637.54 hm2.cropland de-creased between 1993 and 2.00,and 8 2.7.6 hm2.cropland de-creased between 2.00 and 2.08. Compared with cropland,wood-land firstly decreased and then increased,and the other types did not change significantly. The results indicate that CBERS dataset has the application potential in world resources researches.

关键词： land cover the china-Brazil earth {2. satellite (CBERS) support vector machine (SVM) change detection

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^(40)Ar/^(39)Ar age evidence for Altyn fault tectonic activities in western china

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Chinese science Bulletin 2003年第18期48卷 2024-2030页

作者： LIU Yongjiang1, J. Genser2. GE xiaohong1, F. Neubauer2. G. Friedl2. CHANG Lihua1, REN Shoumai3 & R. Handler2.1. college of earth {2.s, Jilin University, Changchun 130061, china 2. Institute of Geology and Paleontology, Salzburg University, Salzburg A-502., Austrilia 3. Statigraphic Research Center for Oil and Natural Gas, Ministry of land and resources, Beijing 100034, china Correspondence should be addressed to Liu Yongjiang (e-mail: liuyj@ ***) college of earth {2.s Jilin University Changchun 130061 China

Four 40Ar/39Ar age groups of mica, hornblende and K-feldspar were obtained from Proterozoic and early Paleozoic metamorphic rocks in the Aksay-Dangjin Pass area, western china. The samples away from the middle shear zone of the Altyn fault belt yield two plateau age groups in the range of 461—445.2.Ma and 414.9—342.8 Ma, respec-tively. They represent the tectono-thermal events that had been recorded in the rocks that were displaced by the Altyn strike-slip fault in late Ordovician-early Silurian and Devo-nian, respectively. These two age groups should be related to the closures of Northern and Southern Qilian Oceans. The deformed granitic gneiss from the northern belt gives a pla-teau age group of 178.4—137.5 Ma, which is interpreted as the active age of the Altyn fault in the middle-late Jurassic- early Cretaceous and should be related to the accretion of Lhasa block to the north. The sample from the middle shear zone of the Altyn fault belt yields two plateau ages of 36.4 and 2..3 Ma, respectively, suggesting the strike-slip move-ment with strong metamorphism at greenschist facies along the Altyn fault in the late Eocene. This event occurred in the most areas of the northern Tibet Plateau and should be in response in the north to the collision between Indian and Eurasian continents. The present study demonstrates that the Altyn fault is characterized by multiple pulse-style activi-ties under the tectonic setting of convergence between the Indian and Eurasian continents.

关键词： Altyn fault 40Ar/39Ar age tectono-thermal event western china

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The Analysis of Dominance Degree of land Use in Irrigation District——A Case Study of Jinghuiqu Irrigation District in Shaanxi Province

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Asian Agricultural Research 2012年第1期4卷 54-57页

作者： ZHOU Lu-hong1, LI Ya-ni2. WANG xiao-feng1 1. college of earth {2. and land resources, Chang’an University, xi’an 710054. china 2. Tourism & Hotel Management Department, Shunde Polytechnic, Shunde 52.333, china

According to the remote sensing interpretation data in study area, statistics and the data concerning agricultural land classification of Shaanxi Province, on the basis of degree of dominance of land use, taking Jinghuiqu Irrigation District as an example, this paper adopts benefit-cost analysis method and the method of degree of dominance of land resources per capita to conduct analysis on degree of dominance of land. The results show that in study area, the ratio of cost and benefit of farmland is 1.5, with relative big value, indicating that farmland is the dominant land resource in Jinghuiqu Irrigation District; the abundance of land resources in study area is 0.73, the combination index of land resources is 2.3, and degree of dominance of land resources per capita is 0.32. indicating that the combination index of land resources in study area is relatively big, while degree of dominance of land resources per capita is relatively small, which shows that in study area, the combination of all kinds of land resources is in a poor state, with poor supporting ability. In view of the status quo that the combination of all kinds of land resources is in a poor state, with poor supporting ability in Jinghuiqu Irrigation District, the corresponding policy suggestions are put forward as follows: first, strictly implement the central policy and protect farmland resources; second, adjust land use structure and strive to promote benefit; third, make rational planning of land resources and take the road of sustainable development; fourth, take the irrigation district as the unit and establish use class and price standard of land in irrigation district.

关键词： Dominance degree of land resources Benefit-cost De

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