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Origin of the Red earth sequence on the northeastern Tibetan Plateau and its implications for regional aridity since the middle Miocene

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science china {2. sciences 2006年第5期49卷 505-517页

作者： WANG Xianyan1,7, LU Huayu1,2. JI Junfeg3, WANG Xiaoyong1,7, ZHAO Jingbo4, HUANG Baochun5 & LI Zhen6 1. SKLLQG, Institute of earth Environment, Chinese Academy of sciences, Xi’an 710075, {2. 2. Department of Urban and resources sciences, Nanjing university, Nanjing 2.0093, {2. 3. Department of earth sciences, Nanjing university, Nanjing 2.0093, {2. 4. Department of Geography, Shaanxi Normal university, Xi’an 710062. {2. 5. Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 10002., {2. 6 Department of Geography, Qinghai Normal university, Xining 810008, {2. 7. Graduate school of the Chinese Academy of sciences, beijing 100039, {2. 1. SKLLQG Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 7. Graduate school of the Chinese Academy of sciences Beijing 100039 China 2. Department of Urban and resources sciences Nanjing University Nanjing 210093 China 3. Department of earth sciences Nanjing University Nanjing 210093 China 4. Department of Geography Shaanxi Normal University Xi’an 710062 China 5. Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China 6. Department of Geography Qinghai Normal University Xining 810008 China

The Red earth deposit around Xining, northeastern Tibetan Plateau, has beenstudied in terms of soil micro-structure, grain-size distribution, major- and trace-elementchemistry and magne-tostratigraphy. Field investigations indicate that the Red earth sequenceconsists of 2. visually definable yellow-brown and weakly-developed soils interbedded with reddishstrongly-developed soils, and has a similar structure to the aeolian Red Clay deposit on the ChineseLoess Plateau. Grain-size analysis shows that the Red earth deposit is very fine-grained with anegligible sand fraction ( > 63 μm). Thin-section observations under light microscopy show that thedeposit has a clayey texture and the coarse fraction ( > 10 μm) mainly consists of quartz,feldspar and micas. Pyroxene and hornblende were also observed. This mineralogical composition ofthe coarse fraction is similar to that of the Quaternary loess. In addition, all of the mineralgrains are semi angular semi-angular and are generally finer than 63 μm. There is a good agreementbetween the major and minor trace element chemistry of loess-soil units and the Red earth *** REE distributions of the loess-soil and the Red earth deposit are similar in shape, withenriched LREE and fairly flat HREE profiles and a clear negative Eu anomaly. The geochemicalcharacteristics of the Red earth deposit are also identical to those of upper continental crust,thus indicating a wind-blown origin. Magnetostratigraphic investigation shows that onset of the Redearth deposition predates 11.4 Ma BP (13.6 Ma at a nearby site). The distribution of the reportedMiocene aeolian loess at Qin''an of the Loess Plateau is still unknown. Our results indicate thatthis aeolian deposit had extended to the northeastern Tibetan Plateau by at least the middleMiocene. The similarity of the element geochemistry between the Red earth deposit and the overlyingloess shows that they may have similar sources and dynamic transport system, and may indicate thatthe

关键词： Red earth deposit, Northeastern Tibetan Plateau, aeolian deposit, aridity of Asia, the middle Miocene.

Effects of abnormally high heat stress on petroleum in reservoir——An example from the Tazhong 18 Well in the Tarim Basin

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science china {2. sciences 2008年第4期51卷 515-527页

作者： ZHU DongYa1, JIN ZhiJun1, HU WenXuan2.& ZHANG XueFeng3 1 Petroleum Exploration and Production Institute, china Petroleum & Chemical Corporation, beijing 100083, china 2.Department of earth sciences, Nanjing university, Nanjing 2.0093, china 3 school of Resource and Information, china university of Petroleum, beijing 102.49, china Petroleum Exploration and Production Institute China Petroleum & Chemical Corporation Beijing China Department of earth sciences Nanjing University Nanjing China school of Resource and Information China University of Petroleum Beijing China

An igneous intrusion of 94m thick was discovered intruding into the Silurian sandstone from Tazhong 18 Well. The petroleum previously preserved in the Silurian sandstone reservoir was altered into black carbonaceous bitumen by abnormally high heat stress induced by the igneous intrusion. The reflec-tance of the carbonaceous bitumen reaches as high as 3.54%, indicating that the bitumen had evolved into a high thermal evolution level. Similar to the Silurian samples from the neighboring Tazhong 11, Tazhong 12. Tazhong 45 and Tazhong 47 wells, the distribution of C2., C2. and C2. steranes of the car-bonaceous bitumen is still "V" -shaped and can still be employed as an efficient parameter in oil source correlation. The "V" -shaped distribution indicates that the hydrocarbons from the Tazhong 18 and the neighboring wells were all generated from the Middle-Upper Ordovician hydrocarbon source rocks. However, the oil source correlation parameters associated with and terpanes had been changed greatly by the high heat stress and can no longer be used in oil source correlation. The δ 13C values of the pe-troleum from the neighboring wells are between -32.53‰ and -33.37‰, coincident with those of the Paleozoic marine petroleum in the Tarim Basin. However, the δ 13C values of the carbonaceous bitumen from the Tazhong 18 Well are between -2..18‰ and -2..2.‰, isotopically much heavier than the pe-troleum from the neighboring wells. The content of light hydrocarbons (nC14-nC2.) of the saturated hydrocarbon fraction in the carbonaceous bitumen is extremely higher than the content of heavy hy-drocarbons. The light/heavy hydrocarbon ratios (ΣnC2.-/ΣnC2.+) are between 4.56 and 39.17. In the saturated fraction, the even numbered hydrocarbons are predominant to the odd numbered, and the OEP (Odd to Even Predominance) values are between 0.2. and 0.49. However, the content of light hy-drocarbons in the petroleum from the neighboring wells is relatively low and the content of the even numb

关键词： Tarim Basin igneous intrusive abnormally high heat stress bitumen carbon isotope PAH

Macro-and microscopic mechanical behaviour of flow of coal samples experimentally deformed at high temperatures and pressures

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Chinese science Bulletin 2005年第S1期50卷 59-66页

作者： LIU Junlai , YANG Guang & MA Rui State Key Laboratory of Geological Processes and mineral resources,{2., beijing 100083, china Key Laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education,{2., beijing 100083, china College of earth sciences, Jilin university, Changchun 130061, china china Univ Geosci State Key Lab Geol Proc & Mineral Resources Beijing 100083 Peoples R China china Univ Geosci Minist Educ Key Lab Lithosphere Tecton & Lithoprobing Technol Beijing 100083 Peoples R China Jilin Univ Coll Earth Sci Changchun 130061 Peoples R China

Coal samples from Qinshui Basin, Shanxi, china are experimentally deformed at temperatures and confining pressures of 2.0 - 500℃and 2.0 - 500 Mpa, strain rate of 0.5×10-5/s and total strain of 10%. The vitrinite reflectance of the coal samples varies from 3.04 to 1.79. It is shown that the strengths of the deformed samples change obviously with coeval increasing temperatures and pressures (T/P). At the experimental range of T/P, the effects of increasing temperature predominate over that of increasing pressure. Microstructural analysis indicates a brittle to ductile transition under experimental T/P conditions from 2.0 to 300℃, and 2.0 to 300Mpa. Brittle deformation microstruc-tures include macroscopic fracture zones and penetrative fracture associations. Elongation, undulose or irregular extinction, deformation lamellae and dynamic recrystallization of grains are the main ductile deformation microstructures. The variation of deformation mechanisms of the experimentally deformed coal samples is related to both the components of coals and T/P conditions. At low T/P, fractures occur in both inertinite and vitrinite of the samples. At higher T/P, crystalline plastic deformations are observed in the inertinite only.

关键词： coal experimental deformation brittle to ductile transition.

Spatial heterogeneity of the driving forces of cropland change in china

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science china {2. sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2. WANG Jinfeng1, LIU Mingliang4,1 & MENG Bin1,2.3 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 Arts and sciences of beijing Union university, beijing 100083, china 4. school of Forestry and Wildlife sciences, Auburn university, Auburn, Alabama, AL36849, USA 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. school of Forestry and Wildlife sciences Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of beijing Union {2. 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in china. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of china, natural condition changes and geographical background were the main constraints and drivers, while in Eastern china, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in china recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, china.

Sorption behavior of U(VI), ^(2.4)U(VI) and ^(2.8)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in china

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science china {2. sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3, WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. Department of earth sciences, State Key Laboratory of {2. Deposit Research, Nanjing university, Nanjing 2.0093, china 2. Center of Materials Analysis, Nanjing university, Nanjing 2.0093, china 3. Department of Environmental science and Engineering, Nanjing university, Nanjing 2.0093, china 4. beijing Geology Institute, Nuclear Industry, beijing 10002., china Department of earth sciences State Key Laboratory of Mineral Deposit Research Nanjing University Nanjing China Center of Materials Analysis Nanjing university Nanjing china Department of Environmental science and Engineering Nanjing university Nanjing {2. beijing Geology Institute Nuclear Industry beijing {2.

The first results of sorption experiments of U(VI), 2.4U(VI) and 2.8U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 2.4U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

The developmental trend of labrum and median eyes of Orsten-type preserved Phosphatocopina (Crustacea)

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science china {2. sciences 2010年第1期53卷 18-26页

作者： LIU Zheng 1,2.& DONG XiPing 1,2.1 school of earth and Space {2.s,Peking university,beijing 100871,china 2.State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of {2.s,Nanjing 2.0008,china 1. school of earth and Space {2.s Peking University Beijing 100871 China2. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China

The Phosphatocopina (Crustacea,Arthropoda) is an important group of 'Orsten-type' preserved *** is resolved as the sister-group of *** we study the labrum,the median eyes,and the inner lamella of Phosphatocopina based on the selected specimens respectively from western Hunan,South china,and *** labrum characters of different species exhibit interspecific *** ratio of labrum length/shield length is significant to the reconstruction of the ontogeny of *** labrum characters should be introduced to the diagnosis of *** the earliest growth stage,the median eyes were inconspicuous,almost as flat as the other area of the ***,with the growth of the individuals they became *** were two obviously concave structures on the ventral side of the hypostome in later stages,which were the positions where the median eyes should have been *** addition,the two modes of preservation of the inner lamella,i.e.,that of shrinking and that of bulging up,are interpreted as the preservational artifact herein.

关键词： Phosphatocopina Crustacea Orsten-type preservation morphology ontogeny Cambrian South china Sweden

"Three-Component" Digital Prospecting Method: A New Approach for mineral resources Quantitative Prediction and Assessment

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Journal of earth science 2004年第3期 6-13页

作者： Zhao Pengda Chioa university of geosciences, Wuhan 430074, {2. Chen Jianping school of the earth sciences and resources, china university of geosciences, beijing 100083, {2. Chen Jianguo Institute of Mathematical Geology, china university of geosciences, Wuhan 430074, {2. Zhang Shouting school of the earth sciences and resources, china university of geosciences, beijing 100083, {2. Chen Yongqing {2. Geological Survey, beijing 100073, {2.

Three-component" method consists of three close-connected aspects: geological anomaly, diversity of mineralization and mineral deposit spectrum. All these three concepts are not new separately, but it is a new approach to combine these three aspects in one single concept for quantitative mineral resources prediction and assessment and it is also the first time to conduct a more detailed study in each aspect. Investigation and clarification of geological anomalies, diversity of mineralization and spectrum of mineral deposits are realized by digitization and quantification of ore forming controlling factors, ore-existing symbols or marks, characteristics of mineralization and regulation of ore-genesis and laws of distribution. These procedures lead to construction of a "digital model" for mineral resources prediction and assessment.

关键词： three-component" method geological anomaly diversity of mineralization spectrum of mineral deposits.

Study on the Removal of Iron,Manganese and Nitrate in Groundwater by Biological Ribbon Technology

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地学前缘 2009年第S1期16卷 190-191页

作者： Yuchen Li,Yukun Ju school of Water resources & Environment,{2. university of geosciences(beijing),beijing 100083,{2.

The pollution of iron,manganese and nitrate in groundwater is a huge threat to human *** this study,column experiments of ceramic,manganese sand,ceramic sand,volcanic rock,quartz sand were *** and manganese contents of influent were 3.3 mg/L and 2.1 mg/*** the biofilm became mature,the highest iron and manganese removal rate achieved by manganese sand as a filter *** did a little worse than manganese sand,but other three filter material could not reach

关键词： removal of iron manganese and nitrate groundwater biological ribbon technology

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.s 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