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

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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Delineation of Potential mineral resources RegionBased on Geo-anomaly Unit

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Journal of earth Science 2000年第2期19卷 66-71页

作者： Chen Yongqing faculty of earth {2., China {3. of geosciences, Wuhan 43.074 The Center for Development and Research, China Geological Survey, beijing 100083.Liu Hongguang faculty of earth {2., China {3. of geosciences, Wuhan 4

The geological anomaly unit method (GAUM) is a new way to delineate and evaluate ore finding targets in line with the “geological anomaly ore finding theory”. Comprehensive ore finding information from geological, geochemical and geophysical data is used for quantitative measurement of the “ore forming geological anomaly unit” in this paper. The main procedures are shown as follows: (1) The geo anomalous events associated with gold mineralization are analyzed in Tongshi gold field; (2. The zonation in the concentrated heavy minerals and the stream sediment elements of ore forming geo anomaly are studied in detail; (3. The deep geological structural framework is deduced by means of the synthetic geological interpretation of gravity and magnetic information; (4) The ore controlling geo anomalies and ore anomalies are chosen as the variables of the favorable ore forming indexes that can be used for the quantitative delineation and evaluation of the potential ore forming regions.

关键词： ore forming geo anomaly unit mineral resources areas comprehensive ore forming information favorable ore forming index Tongshi gold field western Shandong Province Eastern China.

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3. Integrated Geological Modeling in Tongshan Copper Deposit,Heilongjiang Province,China

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地学前缘 2009年第S1期16卷 282-283页

作者： Gongwen Wang,Limei Wang,Ge Cui,Chengyin Tan,Shanyan Jin School of earth sciences and {2.,China {3. of geosciences(beijing),beijing 100083.China.

In this paper,3.-GIS reconstruction and interpolation approach,additional virtual borehole technology and BP network technology are used to explore the concealed ore *** virtual borehole has same function as reality b... 详细信息

关键词： 3. geological modeling virtual borehole BP network mineral exploration Tongshan copper deposit

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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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Analytical method of Cr stable isotope and its application to water pollution survey

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Chinese Science Bulletin 2010年第7期55卷 664-669页

作者： GAO YongJuan 1,2.3.MA Teng 4,5,LING WenLi 1,2.LIU CunFu 4,5 & LI Li 4,5 1faculty of {3. Science,China {2. of geosciences,Wuhan 43.074,China 2.tate Key Laboratory of Geological Processes and mineral resources,China {2. of geosciences,Wuhan 43.074,China 3.Graduate School,China {2. of geosciences,Wuhan 43.074,China 4 Biogeological and Environmental Geology Laboratory of Ministry of Education(China {2. of geosciences) ,Wuhan 43.074,China 5 Sino-Hungary Joint Laboratory of Environmental {12. and Health,China {2. of geosciences,Wuhan 43.074,China faculty of earth Science China University of Geosciences Wuhan 430074 China State Key Laboratory of Geological Processes and mineral resources China University of Geosciences Wuhan 430074 China Graduate School China University of Geosciences Wuhan 430074 China Biogeological and Environmental Geology Laboratory of Ministry of Education (China university of geosciences) Wuhan 430074 China Sino-Hungary Joint Laboratory of Environmental sciences and Health China University of Geosciences Wuhan 430074 China

High Cr(VI) concentration is a potential serious risk to environment and ecologic ***,it is essential to effectively monitor Cr contamination in water systems and scientifically evaluate its evolution trend.A new method of in-situ tracer technique by Cr isotopic analysis for quantitatively estimating Cr-contamination and its regional evolution in natural waters as well as a case application are reported in this *** on documented literatures,an experimental procedure for chemical separation and purification of Cr in water samples and its analytical method for Cr isotopic measurement by thermal ionization mass spectrometry(TIMS) are *** samples collected around a chemical factory in Hubei Province were analyzed by this *** samples showδ53.r values ranging from-1.7‰to 7.3.and an elevating trend with an increasing in distance from the sampling site to pollution source.A functional correlation following Rayleigh fractionation law was established between sample'sδ53.r value and its extent of Cr *** study suggests that Cr isotopic analysis is an effective method to reveal the spatial distribution and its evolution trend of Cr contamination in the regional water *** is thus helpful to assessing the self-purifying ability of local water system according to Cr isotopic fractionation.

关键词：铬(VI) 水污染调查稳定同位素应用同位素分析供水系统演变趋势示踪技术

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Anatexis in Himalayan crust:Evidence from geochemical and chronological investigations of Higher Himalayan Crystallines

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Science China earth sciences 2005年第9期48卷 1347-1356页

作者： YANG Xiaosong1, JIN Zhenmin2.& MA Jin1 1. State Key Laboratory of earthquake Dynamics, Institute of Geology, China earthquake Administration, {2. 10002., China 2. faculty of earth sciences, China university of geosciences, Wuhan 43.074, China 1. State Key Laboratory of earthquake Dynamics Institute of Geology China Earthquake Administration 100029 Beijing China 2. faculty of earth {2. China University of Geosciences 430074 Wuhan China

Migmatization in Higher Himalayan Crystallines (HHC) results from anatexis. The widely distributed migmatites in HHC are an important clue to investigate the relationship be- tween anatexis and the origins of Higher Himalayan leucogranites (HHL), and to understand the effect of anatexis on crustal evolution during the post-collision period. We studied in detail the chemical features of three basic constituent parts of the migmatites, i.e. leucosome, mesosome and melanosome, and determined the K-Ar ages of leucosomes. Our studies indicate that type-I leucosome is the product of crystallization of melt generated by partial melting of mesosome at source region, but type-II leucosome and HHL probably underwent crystallization differentiation of plagioclase during melt aggregation and migration. The age of 2..67 Ma of Type-I leucosome, which is a little older than the beginning of MCT movement, indicates that anatexis may have played an important role in the formation of MCT. That the ages of type-II leucosome (ranging from 14.82.to 18.3. Ma) are consistent with that of HHL provides new chronological evidence for the relationship between migmatization and HHL. We obtained a very young age of 6.2. Ma of Type-II leucosome that provides new time constraint on magma activity in the central segment of Higher Himalayas.

关键词： Higher Himalayan Crystallines, migmatite, anatexis, leucosome, K-Ar age.

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Sedimentary Facies Architectures of Third-Order Sequences from Early to Middle Triassic in Nanpanjiang Basin

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Journal of China university of geosciences 2003年第2期14卷 103-118页

作者： Mei Mingxiang Ma Yongsheng Deng Jun Gao Jinhan Chen Huijun Meng Qingfen Li Donghai faculty of earth {2. and {3., China university of geosciences, beijing 100083 faculty of earth {2. and {3. China University of Geosciences Beijing 100083

There are complex and regular changes on sedimentary facies from the Early to the Middle Triassic in the Nanpanjiang basin. After the obvious drowned event of carbonate platforms in the transitional period between Permian and Triassic, carbonate platforms have evolved into the ramp type from the rimmed shelf type. The differentiation of sedimentary facies becomes clearer in space, which are marked by the changes from an attached platform to a turbidity basin and several isolated platforms in the basin. The striking characteristics are the development of oolitic banks on isolated platforms in Nanning and Jingxi and the reef and bank limestones in the margin of the attached platform in the Early Triassic. Despite the difference of the time span and the architecture of facies succession of third order sedimentary sequences, the process of the third order relative sea level changes reflected by the sedimentary facies succession of the third order sequences is generally synchronous. Therefore, six third order sequences could be discerned in the strata from the Early to the Middle Triassic in the Nanpanjiang basin. Using two types of facies changing surfaces and two types of diachronisms in stratigraphic records as the key elements, the sedimentary facies architectures of the third order sequences that represent sequence stratigraphic frameworks from the Early to the Middle Triassic in the Nanpanjiang basin could be constructed.

关键词： sedimentary facies architectures third order sequences Early to Middle Triassic Nanpanjiang basin.

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Thermodynamic conditions of framework grain dissolution of clastic rocks and its application in Kela 2.gas field

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Science China earth sciences 2005年第1期48卷 21-31页

作者： LAI Xingyun, YU Bingsong, CHEN Junyuan, CHEN Xiaolin, LIU Jianqing, MEI Mingxiang, JING Weiguang & CHENG Suhua School of earth sciences and {2. {3., China university of geosciences, beijing 100083. China Key Laboratory of Lithospheric Tectonics, Deep-level Process and Exploration of Ministry of Education, beijing 100083. China 1. China university of geosciences School of Earth Sciences and Mineral Resources 100083 Beijing China 2. Key Laboratory of Lithospheric Tectonics Deep-level Process and Exploration of Ministry of Education 100083 Beijing China

Feldspar and clastic debris are the most important constituent framework grains of sedimentary clastic rocks and their chemical dissolution plays an essential role in the formation and evolution of the secondary pore in the reservoir rocks. On the basis of thermodynamic phase equilibrium, this study investigates the chemical equilibrium relationships between fluid and various plagioclase and K-feldspar in diagenesis of the sediments, particularly, the impact of temperature and fluid compositions (pH, activity of K+, Na+, Ca2. and so on) on precipitation and dissolution equilibria of feldspars. Feldspar is extremely easily dissolved in the acid pore water with a low salinity when temperature decreases. The dissolution of anorthite end-member of plagioclase is related to the Ca content of the mineral and the fluid, higher Ca either in the mineral or in the fluid, easier dissolution of the feldspar. Moreover, the dissolution of albite end-member of plagioclase is related to Na of both the mineral and fluid, lower Na out of both the mineral and fluid, easier dissolution of the mineral. Similarly, lower-K fluid is more powerful to dissolve K-feldspar than the higher. The anorthite component of plagioclase is most easily dissolved in ground water-rock system, the albite is the secondary, and K-feldspar is the most stable. Selective dissolution of plagioclase occurs in diagenesis because of the plagioclase solid solution that is mainly composed of albite and anorthite end-members, Ca-rich part of which is preferentially dissolved by the pore water, in contrast to the Na-rich parts. Based on investigation of reservoir quality, secondary pore, dissolution structures of feldspar, clay minerals and ground water chemistry of the Kela 2.gas field of Kuqa Depression in the Tarim basin of Western China, we discovered that the secondary pore is very well developed in the highest quality section of the reservoir, and the plagioclase of which was obviously selectively dissolved, in c

关键词： dissolution of feldspar, thermodynamic conditions, groundwater pore chemistry, Kela 2 gas field.

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Dissolution Precipitation Wave Structure of Hydrothermal Ore Zoning

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Journal of earth Science 1995年第1期14卷 85-96页

作者： Yu Chongwen(faculty of earth {2., China {3. of geosciences,Wuhan 43.074)Jiang Yaosong Xiao Zhengyu(Department of Computer Science,China {3. of geosciences, beijing 100083.

Hydrothermal ore zoning is a transport-reaction problem in which infiltration is the principal Prcness of transport and dissolution/Precipitation is the Principal process of chemical *** diffusion and ion exchange/adsorption would not affect the basic attributes of hydrothermal ore zoning. Hydrothermal ore zoning belongs essentially to infiltration metasomatic zoning, it results from the formation and propagation of dissolution/precipitation waves through Permeable media. The authors apply the theory of coupled infiltration and dissolution/precipitation reactions in Physicochemical hydrodynamics to studying the structural characteristics of dissolution/precipitation waves, and apply furthermore the coherence principle in dynamic theory of multicomponent coupled systems to revealing the dynamic mechanisms of their formation. The results of investigation verify and develop . C. 's theory of infiltration metasomatic zoning,on the one hand, raising it from the qualitative, equilibrium thermodynamic basis to the quantitative dynamic level;on the other hand, and more importantly, applying theories of Physicochemical hydrodynamics and dynamics of multicomponent coupled systems to bringing to light the dynamic mechanisms of formation of the structure of hydrothermal ore zoning, and advancing a theory of hydrothermal ore zoning, putting forward new ideas on the nature of the problem of hydrothermal ore zoning, the essence of hydrothermal ore zoning and the structural characteristics and mechanisms of formation of hydrothermal ore zoning.

关键词： hydrothermal ore zoning,transport-reaction,infiltration metasomatism dissolution/ Precipitation waves,Physicochemical hydrodynamics,theory of coupled infiltration and dissolution/precipitation reactions dynamic theory of multicomponent coupled systems,c

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