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Genetic Types of Meter-Scale Cyclic Sequences and Fabric Natures of Facies Succession

Journal of earth Science 2000年第4期19卷 3-10页

作者： Mei Mingxiang Xu Debin Zhou Hongrui Institute of earth sciences and Natural {2., China {3. of geosciences, beijing 100083

Different genetic types of meter-scale cyclic sequences in stratigraphic records result from episodic accumulation of strata related to Milankovitch cycles. The distinctive fabric natures of facies succession result from the sedimentation governed by different sediment sources and sedimentary dynamic conditions in different paleogeographical backgrounds, corresponding to high-frequency sea-level changes. Naturally, this is the fundamental criterion for the classification of genetic types of meter-scale cyclic sequences. The widespread development in stratigraphic records and the regular vertical stacking patterns in long-term sequences, the evolution characters of earth history and the genetic types reflected by specific fabric natures of facies successions in different paleogeographical settings, all that show meter-scale cyclic sequences are not only the elementary working units in stratigraphy and sedimentology, but also the replenishment and extension of parasequence of sequence stratigraphy. Two genetic kinds of facies succession for meter-scale cyclic sequence in neritic-facies strata of carbonate and clastic rocks, are normal grading succession mainly formed by tidal sedimentation and inverse grading succession chiefly made by wave sedimentation, and both of them constitute generally shallowing upward succession, the thickness of which ranges from several tens of centimeters to several meters. The classification of genetic types of meter-scale cyclic sequence could be made in terms of the fabric natures of facies succession, and carbonate meter-scale cyclic sequences could be divided into four types: L-M type, deep-water asymmetrical type, subtidal type and peritidal type. Clastic meter-scale cyclic sequences could be grouped into two types: tidal-dynamic type and wave-dynamic type. The boundaries of meter-scale cyclic sequences are marked by instantaneous punctuated surface formed by non-deposition resulting from high-frequency level changes, which include

关键词： genetic types fabric natures of facies succession meter-scale cyclic sequences.

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Run off-on-out method and models for soil infiltrability on hill-slope under rainfall conditions

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Science China earth sciences 2006年第2期49卷 193-201页

作者： LEI Tingwu1,2. LIU Han1, PAN Yinghua3. ZHAO Jun2. ZHAO Shiwei2.& YANG Yonghui2.1. The Key Laboratory of Modern Precision Agriculture System Integration Research, College of Hydraulic and Civil Engineer-ing, China Agricultural university, beijing {2. China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Yangling 712.00, China 3. Geographic and resources Management College, Yantai Normal university, Yantai 2.402., China 1. The Key Laboratory of Modern Precision Agriculture System Integration Research College of Hydraulic and Civil Engineering China Agricultural University Beijing 100083 China 2. State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water Conservation Yangling 712100 China 3. Geographic and resources Management College Yantai Normal University Yantai 264025 China

The soil infiltrability of hill-slope is important to such studies andpractices as hydrological process, crop water supply, irrigation practices, and soil erosion. A newmethod for measuring soil infiltrability on hill-slope under rainfall condition with run off-on-outwas advanced. Based on water (mass) balance, the mathematic models for soil infiltrability estimatedfrom the advances of runoff on soil surface and the water running out of the slope were *** of 2.cases were conducted. Case Ⅰ was done under a rainfall intensity of 2. mm/h, at aslope gradient of about 0° with a runoff/on length (area) ratio of 1 : 1. Case Ⅱ was under arainfall intensity of 60 mm/h and a slope of 2.° with a runoff/on length (area) ratio of 1 : *** ring method was also used to measure the infiltrability for comparison purposes. Theexperiments were done with soil moisture of 10%. Required data were collected from laboratoryexperiments. The infiltrability curves were computed from the experimental data. The resultsindicate that the method can well conceptually represent the transient infiltrability process, withcapability to simulate the very high initial soil infiltrability. The rationalities of the methodand the models were validated. The errors of the method for the two cases were 1.82./1.3.% and4.49%/3.52.% (Experimental/Model) respectively, as estimated by comparing the rainfall amount withthe infiltrated volume, to demonstrate the accuracy of the method. The transient and steadyinfiltrability measured with double ring was much lower than those with this new method, due towater supply limit and soil aggregates breaking down at initial infiltration stage. The method canovercome the short backs of the traditional sprinkler method and double ring method for soilinfil-traility. It can be used to measure the infiltrability of sloped surface underrainfall-runoff-erosion conditions, in the related studies.

关键词： Infiltrability, runoff-on-out, rainfall, sloped surface, model.

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Effect of upward ion on field-aligned currents in the near-earth magnetotail

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 673-680页

作者： ZHANG LingQian1, LIU ZhenXing1, MA ZhiWei2. SHEN Chao1, ZHOU XuZhi3.& ZHANG XianGuo3.1 Center for Space and Applied Research, Chinese Academy of sciences, beijing 100080, China 2.Institute of Plasma Physics, Chinese Academy of sciences, Hefei 2.003., China 3.school of earth and Space Science, Peking university, beijing 100871, China 1. Center for Space and Applied Research Chinese Academy of Sciences Beijing 100080 China 2. Institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China 3. school of earth and Space Science Peking University Beijing 100871 China

A 3.dimensional resistive MHD simulation was carried out to study the effect of the upward ions on the field-aligned currents (FACs) in the near-earth magnetotail. The simulation results show that the up-flow ions originating from the nightside auroral oval would drift into the center plasma sheet along the magnetic field lines in the plasma sheet boundary, and have an important effect on the field-aligned currents. The main conclusions include that: 1) the upward-ions mainly affect the field- aligned currents in the near-earth magnetotail (inside 15 Re); 2. the generated FACs in the near-earth region have two types, i.e., Region 1 FAC in the high-latitude and Region 2.FAC in the low-latitude; 3. FACs increase with the enhancement of the upward ion flux; 4) with the same flux of the upward ions, FACs enhance with the increase of the velocity of the up-flow ions; 5) the intensification of FACs is also closely related with the latitude of the upward ions, and the ions from the closed field line region generate larger FACs; 6) the generation of FACs is closely related with By created by the upward ions.

关键词： up-flow ions, near-earth magnetotail, field-aligned current

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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,China {2. of {3.(beijing),beijing 100083.China

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

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The impact of vegetation restoration on erosion-induced sediment yield in the middle Yellow River and management prospect

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Science China earth sciences 2005年第6期48卷 724-741页

作者： CHEN Hao1, ZHOU Jinxing2. CAI Qiangguo1, YUE Zhongqi3. LU Zhongchen4, LIANG Guanglin1& HUANG Jianguo5 1. Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural resources Re-search, Chinese Academy of sciences, beijing 100101, China 2. Institute of Forestry, Chinese Academy of Forestry sciences, beijing 100091, China 3. Department of Civil Engineering, university of Hong Kong, Hong Kong, China 4. Eco-environmental Research Center, Chinese Academy of sciences, beijing 100085, China 5. College of resources and Environment, Southwest Agricultural university, Chongqing 400716, China Correspondence should be addressed to Chen Hao 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of Forestry Chinese Academy of Forestry Sciences 100091 Beijing China 3. Department of Civil Engineering University of Hong Kong Hong Kong China 4. Eco-environmental Research Center Chinese Academy of Sciences 100085 Beijing China 5. College of resources and Environment Southwest Agricultural University 400716 Chongqing China

According to the characteristics of water and erosion environments of different natural zones on the Loess Plateau, this paper studies changes of vegetation types, distribution boundaries of forest and grass as well as restoration capacity of vegetation in different natural zones in the middle Yellow River. The annual precipitation of 53. mm is the critical annual pre-cipitation for forest and grass distribution in the middle Yellow River. Among the zonal and azonal environmental factors affecting watershed sediment yield, the intermediate diameter D50 (mm) of suspended load and forest coverage (V, %) play the leading role. Of them the effect weight of forest coverage (V, %) on catchments sediment yield is only 3.4% less than the role of the intermediate diameter (D50, mm), they are almost the same. To effectively control soil erosion in semiarid, especially in hilly-gullied areas and make sediment transport modulus reduce to less than 6000 t/km2. it is rather difficult by merely relying on natural restoration of forest. In the process of cultivated land conversion into forest land and grassland, measures suiting local conditions should be adopted in tree species selection and artificial afforestation (grass planting) based on management with biological measures for slopeland and engineering measures for hilly-gullied areas, so that watershed forest coverage in key counties can reach at least over 3.%.Compared with the standard period of precipitation prior to the 1960s, with the decrease of an-nual precipitation at various periods, plant productivities decline to different degrees under natural conditions. The main reason accountable for the low survival rate of new seedlings and grass over years is due to precipitation decrease. In light with regression models of annual pre-cipitation and natural vegetation productivities, it is possible to obtain estimated values of wa-tershed natural vegetation productivity and eco-water consumption needed for the restoration to

关键词： vegetation restoration, eco-water requirement, watershed sediment yield, the middle Yellow River.

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Simulating the transfer and fate of hexachlorocyclohexane in recent 50 years in beijing, China

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Science China earth sciences 2005年第12期48卷 2203-2213页

作者： CAO Hongying1, LIANG Tao1 & TAO Shu2.1. Institute of Geographical sciences and Natural resources Research, Chinese Academy of sciences, beijing 100101, China 2. Laboratory for earth Surface Processes, Peking university, beijing 100871, China 1. Institute of Geographical sciences and Natural resources Research Chinese Academy of Sciences 100101 Beijing China 2. Laboratory for earth Surface Processes Peking University 100871 Beijing China

Taking beijing as a study area, a dynamic fugacity model was used to simulate the transfer and fate of technical HCHs according to the physic-chemical properties of the studying environment and HCH isomers. Dynamic changes of the transfer fluxes and concentrations of HCH isomers during 1952.2.03.were simulated and the model results suggest good agreement between the calculated and measured concentrations of HCH isomers. During 1952.1983. the average input and output amount of HCHs through agricultural application and degradation are 13. t and 150 t respectively. The dominant transfer processes of HCHs in the study area are air-soil deposition, soil erosion and soil-air diffusion, transfer fluxes of these processes are 80 t?a?1, 16 t?a?1 and 11 t?a?1, which account for 92. of total transfer fluxes of HCHs isomers. There were approximately 2.3. HCHs in all environmental compartments of the study area during this period and 97% of which existed in soil compartment. Air and water advection became the dominant input sources of HCHs after 1984 when the application of technical HCHs was prohib-ited, concentration of HCHs quickly descended to a quite low level in several years. Total amount of HCHs isomers remaining in the study area environment now is less than 5% that before 1983. and this percentage may descend to 0.5% after 2. years by prediction.

关键词： fugacity model, hexachlorocyclohexane, compartment, transfer flux, fate.

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Differential Hydrological Grey Model (DHGM) with self-memory function and its application to flood forecasting

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Science China(Technological sciences) 2009年第4期52卷 1039-1049页

作者： CHEN XiangDong1, XIA Jun1,2.& XU Qian3.1 Key Laboratory of Water Cycle and Related Land Surface Processes, Institute of Geographic sciences and Natural resources Research, Chinese Academy of sciences, beijing 100101, China 2.State Key Laboratory of Water resources and Hydropower Engineering Science, Wuhan university, Wuhan 43.072. China 3.school of Hydrology and Water resources, Hohai university, Nanjing 2.0098, China 1. Key Laboratory of Water Cycle and Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China 2. State Key Laboratory of Water resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China 3. school of Hydrology and Water resources Hohai University Nanjing 210098 China

This paper addresses a problem of flood forecasting with the self-memory function. Considering flood forecasting’s uncertainty and updating demand, a hybrid hydrological model, namely Differential Hy- drological Grey Model with self-memory function (DHGM-SM), is developed. The model has two fold features. One is to establish a self-memorization equation linked with DHGM, that could extract useful information from past data series and realize updating of hydrological dynamic process. The other is that this model has higher efficiency relative to original hydrological model without self-memory func- tion. This approach was applied to river flow forecasting of two representative basins in Tunxi of South China and Daqinggou of North China. It is shown that this hybrid method has satisfactory forecasting accuracy by examination of both calibration and validation.

关键词： differential grey model the self-memorization principle real-time forecasting faded-memory recursive least square method

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Paleoceanographic evolution recorded in the northern South China Sea since 4 Ma

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Science China earth sciences 2005年第12期48卷 2166-2173页

作者： HUANG Baoqi1,2. JIAN Zhimin2.& WANG Pinxian2.1. {3. of earth and Space {2., Peking university, beijing 100871, China 2. Laboratory of Marine Geology, Tongji university, Shanghai 2.0092. China 1. school of earth and Space {2. Peking University 100871 Beijing China 2. Laboratory of Marine Geology Tongji University 200092 Shanghai China

Upper water structure over the last 4 million years in the northern South China Sea (SCS) was reconstructed by sea surface temperature (SST) and primary productivity estimated by changes in the abundance of planktonic foraminifer, planktonic foraminifer transfer function, and the accumulation rate of benthic foraminifera. Results of SST and primary productivity show that SST gradually decreased since 4 Ma, but differential seasonal temperature and primary productivity increased in steps mainly at about 3.1, 2.7, 2.1, 1.6, 0.9 and 0.5 Ma. Comparison with tectonics and orbital variations indicates that phased rising of the Tibet since 3.6 Ma, closing of Panama and Indonesian seaways, and orbital changes were responsible for the changes of upper water structure in the SCS, respectively.

关键词： northern South China Sea, upper water structure, Late Pliocene, planktonic foraminifer, ODP 1146.

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Combination of drainage, water supply and environmental protection as well as rational distribution of water resource in Zhengzhou mining district

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Science China earth sciences 2005年第10期48卷 1768-1779页

作者： WU Qiang1, LI Duo1,2. DI Zhiqiang3. MIAO Ying3. ZHAO Suqi4 & GUO Qiwen5 1. Resource Exploitation Engineering College, CUMT, beijing 100083. China 2. Shijiazhuang Engineering College, {2. of Economics, Shijiazhuang 05003., China 3. Shenyang Institute of Geology and Mineral resources, Shenyang 11003.0} China 4. State Adminstration of Coal Mine Safety, beijing 100013. China 5. Zhengzhou Coal Mine Company (Group), Zhengzhou 452.71, China Resource Exploitation Engineering College CUMT Beijing China Shijiazhuang Engineering College university of Economics Shijiazhuang China Shenyang Institute of Geology and Mineral resources Shenyang China State Adminstration of Coal Mine Safety beijing China Zhengzhou Coal Mine Company (Group) Zhengzhou China

The geological condition of coalfield is much complex in China. With increasing in mining depth and drainage amount, the contradiction of drainage, water supply and environ-mental protection is becoming more and more serious. However, the contradiction can be solved by the scientific management of optimizing combination of drainage, water supply and environ-mental protection. The Philip multiple objectives simplex method used in this article has searched for a possible solution at the first step, and then it goes on searching to find out whether there is a weight number that can lead the solution to the biggest. It can reduce the randomness and diffi-culty of traditional weight method which determine the weight number artificially. Some beneficial coefficients are vague and the number is larger in the model of water resource dispatch. So the vague layer analysis method can consider these vague factors fully, combining the qualitative and quantitative analysis together. Especially, this method can quantify the experiential judge-ment of policy decider, and it will turn to be more suitable if the structure of objective factors is complex or the necessary data are absent. In the paper, the two methods above are used to solve the plans of drainage, water supply and optimizing distribution of water resource in the Zhengzhou mining district.

关键词： combination of drainage, water supply and environmental protection, Philip multiple objective simplex method, vague layer analysis method, distribution of water resource.

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Effect of Aqueous Colloids on Arsenic Geochemistry:Evidences from Ultrafiltration of High Arsenic Groundwater in the Hetao Basin,Inner Mongolia

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地学前缘 2009年第S1期16卷 20-21页

作者： Bo Zhang,Huaming Guo school of Water resources & Environment,China {2. of {3.(beijing),beijing 100083.China.

Groundwater colloidal particles are believed to affect element geochemical behavior in groundwaters, which would mobilize trace element in the groundwater *** of As geochemisttry as impacted by colloids was carried out by using ultrafiltration technology in the Hetao basin,Inner *** groundwater sampling points have been chosen,including five with high As concentration (>100μg/L) and one with low As concentra-

关键词： As mobilization hydrogeochemistry particle dissolved organic carbon inorganic colloid

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