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Science china earth {2. 2009年第6期52卷 784-796页

作者： ZHANG HuaQiao1,2.& DONG XiPing1,2.1 school of earth and Space {2.,Peking university,Beijing 100871,china 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of {2.,Nanjing 2.0008,china school of earth and Space {2. Peking University Beijing 100871 China State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

Although fossils of Orsten-type preservation represented by Skaracarida and Phosphatocopina were first reported from the Middle and Upper Cambrian in western Hunan, South china in 2.05, diversified phosphatocopine species have never been appropriately described and elucidated in terms of their evolutionary relationships. Here, we described two new species of Phosphatocopina, Vestrogothia anterispinata sp. nov. and V. bispinata sp. nov. The evolutionary relationship among all the valid species of Phosphatocopina is discussed and the phylogeny of Phosphatocopina is reestablished using cladistic analysis. Accordingly, phosphatocopines primitively evolved along two lineages: one evolved towards the emergence of lobes; the other evolved towards the emergence of dorsal spines. Respectively, lobes originated independently three times, and dorsal spines originated only once. With regard to the dorsal rims, interdorsum originated first, whereas dorsal furrow originated independently twice on the basis of interdorsum. Probably Hesslandona may represent a polyphyletic group, whereas Vestrogothia a monophyletic group.

关键词： fossils of Orsten-type preservation Vestrogothia Phosphatocopina Crustacea evolution phylogeny Cambrian Hunan

3D Geological Modeling with Multi-source Data Integration in Polymetallic Region:A Case Study of Luanchuan,Henan Province,china

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地学前缘 2009年第S1期16卷 166-167页

作者： Gongwen Wang~(1,2.,Shouting Zhang~(1,2.,Changhai Yan~3,Yaowu Song~3,Limei Wang~1 1.school of earth {2. and resources,china university of geosciences(Beijing),Beijing 100083,china. 2.State Key laboratory of Geological Processes and mineral resources,china university of geosciences,Beijing 100083,china 3.Henan Institute of Geological Survey,Zhengzhou 450007,china

The development of 3D geological models involves the integration of large amounts of geological data,as well as additional accessible proprietary lithological, structural,geochemical,geophysical,and borehole ***,the case study area,southwestern Henan Province,is an important molybdenum-tungsten -lead-zinc polymetallic belt in china.

关键词： 3D geological modeling multi-source data mineral exploration metallogenic model virtual geological section Luanchuan polymetallic region

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 earth {2. 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.

Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central china: Constraints from geochemistry and melt inclusions

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Science china earth {2. 2005年第8期48卷 1146-1157页

作者： SU Li1,2. SONG Shuguang3 & ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern university, Xi’an 710069, china 2. The Geological Lab Center,{2. (Beijing), Beijing 100083, china 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, Peking university, Beijing 100871, china 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab Center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 2. km2. is the largest ultramafic massif in the eastern Qinling orogenic belt, Central china. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2.3, CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

Numerical study of the auroral particle transport in the polar upper atmosphere

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Science china(Technological sciences) 2008年第10期51卷 1759-1771页

作者： CAI HongTao1,2. MA ShuYing1,2.& PU ZuYin3 1 school of Electronic Information, Wuhan university, Wuhan 430079,{2. 2.Key Laboratory of Geospace Environment and Geodesy, Ministry of Education of PRC, Wuhan 430079,{2. 3 school of earth and Space sciences, Peking university, Beijing 100871,{2. 1. school of Electronic Information Wuhan University Wuhan 430079 China 2. Key Laboratory of Geospace Environment and Geodesy Ministry of Education of PRC Wuhan 430079 China 3. school of earth and Space {2. Peking University Beijing 100871 China

Starting from the Boltzmann equation and with some reasonable assumptions, a one-dimensional transport equation of charged energetic particles is derived by taking account of major interactions with neutral species in the upper atmosphere, including the processes of elastic scattering, the excitation, the ionization and the secondary electron production. The transport equation is numerically solved, for a simplified atmosphere consisting only of nitrogen molecules (N2., to obtain the variations of incident electron fluxes as a function of altitude, energy and pitch angle. The model results can describe fairly the transport characteristics of pre-cipitating auroral electron spectra in the polar upper atmosphere; meanwhile the N2.ionization rates calculated from the modeled differential flux spectra also exhibit good agreements with existing empirical models in terms of several key parameters. Taking the energy flux spectra of precipitating electrons observed by FAST satellite flying over EISCAT site on May 15, 1997 as model inputs, the model-calculated ionization rate profile of neutral atmosphere consists reasonably with that recon-structed from electron density measurements by the radar.

关键词： aurora particle precipitation polar upper atmosphere electron transport equation numerical simulation

Effects of salinity on methane gas hydrate system

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Science china earth {2. 2007年第11期50卷 1733-1745页

作者： YANG DingHui1 & XU WenYue2.1 Department of Mathematical sciences, Tsinghua university, Beijing 100084,{2. 2.school of earth & Atmospheric sciences, Georgia Institute of Technology, Atlanta, GA 30332. USA 1. Department of Mathematical sciences Tsinghua University Beijing 100084 China 2. school of earth & Atmospheric {2. Georgia Institute of Technology Atlanta GA 30332 USA

Using an approximately analytical formation, we extend the steady state model of the pure methane hydrate system to include the salinity based on the dynamic model of the methane hydrate system. The top and bottom boundaries of the methane hydrate stability zone (MHSZ) and the actual methane hy-drate zone (MHZ), and the top of free gas occurrence are determined by using numerical methods and the new steady state model developed in this paper. Numerical results show that the MHZ thickness becomes thinner with increasing the salinity, and the stability is lowered and the base of the MHSZ is shifted toward the seafloor in the presence of salts. As a result, the thickness of actual hydrate occur-rence becomes thinner compared with that of the pure water case. On the other hand, since lower solubility reduces the amount of gas needed to form methane hydrate, the existence of salts in sea-water can actually promote methane gas hydrate formation in the hydrate stability zone. Numerical modeling also demonstrates that for the salt-water case the presence of methane within the field of methane hydrate stability is not sufficient to ensure the occurrence of gas hydrate, which can only form when the methane concentration dissolved in solution with salts exceeds the local methane solubility in salt water and if the methane flux exceeds a critical value corresponding to the rate of diffusive methane transport. In order to maintain gas hydrate or to form methane gas hydrate in marine sedi-ments, a persistent supplied methane probably from biogenic or thermogenic processes, is required to overcome losses due to diffusion and advection.

关键词： methane gas hydrate,solubility,stability of hydrate,salinity,phase equilibrium

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

A Reconstruction for the Late Paleozoic Tectonic Evolution of the Tekes Daban Area,Western Tianshan Mountains:Evidence from Unconformities

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Acta Geologica Sinica(English Edition) 2011年第5期85卷 1127-1133+1135-1136+1134页

作者： LI Yongjun~(1,*),YANG Gaoxue~1,WANG Xiaogang~2.ZHANG Tianji~1,LIU Xiaoyu~1, YANG Mingyi~1 and TONG Liming~2.1 school of earth {2. and resources Management,Chang’an university,Xi’an 710054,china 2.No.9 Geological Brigade,Xinjiang Bureau of Geology and mineral Exploration and Development,(U|¨)rmqi 830000,china school of earth {2. and resources Management Chang'an University Xi'an 710054 China No. 9 Geological Brigade Xinjiang Bureau of Geology and Mineral Exploration and Development ürümqi 830000 China *Correspondence: Yongjun LI *Correspondence: Corresponding author. E-mail: yongjunl@***

The identification of unconformities is the key to reconstructing tectonic evolution,revealing crust movement and establishing tectonic *** a long time,there were some controversial issues on the episodes of Variscan cycle(especially on the period of Carboniferous-Permian stages) of the Tianshan *** essential questions fall on the numbers and property of unconformities in this area, for example,in the western Tianshan *** research only recognized three or four fold *** regional geological mapping of 1:50000 in the Tekes Daban area,western Tianshan have allowed us to characterize the seven unconformities within the Carboniferous-Permian strata and understand its implications for tectonic reconstruction of the Tianshan *** angular unconformities,which indicate that seven tectonic episodes occurred in the Late Paleozoic Period,were identified in this ***,the newly discovered unconformities based on the angle-unconformity between the Dongtujinhe and Keguqinshan Formations,and angle-unconformity between the Wulansayi and Wulang Formations,respectively indicates the Tekes episode and Gongliu *** unconformity between the Dongtujinhe and Yishijilike Formations is angle-unconformity instead of parallel unconformity indentified by previous research,so the former Bogda ascending can be revised as Bogda ***,these newly identified seven episodes,including the Tekes episode,suggest that there are seven tectonic movements in the Tianshan area at *** has significant implications for reconstruction of the Late Paleozoic tectonics in the Tianshan Area,NW china.

关键词： unconformity episode Late Paleozoic Western Tianshan Mountains

*** Geological Relic Types and Functional Zoning Establishment

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地学前缘 2009年第S1期16卷 291-292页

作者： Sizuo Wang,Jianping Zhang,Chen Ni,Tingting Dong school of the earth {2. and resources,china university of geosciences(Beijing),Beijing 100083,china.

Many of the beautiful geological features are formed by Jurrasic granites,such as granite picotgraphic stone, granite peak cluster,scouring ditches,miarolitic cavity, islands,beaches,sea caves and so *** are distinctive Shezu cultural relics and ancient architecttures preserved from Tang and Song *** a practical point of view that the development and protection of geoheritage need in accordance with the diversity of landforms and the uniqueness of culture,this

关键词： Mt.Taimushan functional zoning geoheritage conservation

Zircon and apatite fission track analyses on mineralization ages and tectonic activities of Tuwu-Yandong porphyry copper deposit in northern Xinjiang, china

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Science china earth {2. 2007年第12期50卷 1787-1795页

作者： YUAN WanMing1,BAO ZengKuan2.DONG JinQuan2.GUO ZhaoJie3 & DENG Jun1 1 State Key Laboratory of Geological Processes and mineral resources,{2. university of geosciences,Beijing100083,{2. 2.Laboratory of Nuclear Analysis Techniques,Institute of High Energy Physics,Chinese Academy of sciences,Beijing 100039,{2. 3 Department of Geology,Peking university,Beijing 100871,{2. 1. State Key Laboratory of Geological Processes and mineral resources China University of Geosciences Beijing 100083 China 2. Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100039 China 3. Department of Geology Peking University Beijing 100871 China

The mineralization ages reported in the past in the Tuwu-Yandong copper district not only are different,but also fall into the Hercynian *** study has achieved 9 zircon and 7 apatite fission track analysis *** zircon fission track ages range from 158 Ma to 2.9 Ma and the apatite ages are between 64 Ma and 140 *** mineralization accords with the regional tectonics in the copper *** consider that the zircon fission track age could reveal the mineralization age based on annealing zone temperature of 140―300℃ and retention temperature of ～2.0℃ for zircon fission track,and metallogenetic temperature of 12.―350℃ in this ore *** three mineralization epochs have been identified,i.e.,2.9―2.6 Ma,2.2.2.0 Ma and 165―158 Ma,and indicate occurrence of the min-eralization in the Indosinian and Yanshan *** to apatite fission track ages,the three tectonic-mineralizing epochs are 140―132.Ma,109―97 Ma and 64 Ma,which means age at about 100℃ after the *** three epochs lasted 146 Ma,108 Ma and about 100 Ma from ～2.0℃ to ～100℃ and trend decrease from early to *** is shown by the fission track modeling that this district underwent three stages of geological thermal histories,stable in Cretaceous and cooling both before Cretaceous and after 2. Ma.

关键词： mineralization age, tectonic epoch, fission track, zircon, apatite, Tuwu-Yandong, Xinjiang