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Development of distributed time-variant gain model for nonlinear hydrological systems

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Science China earth sciences 2005年第6期48卷 713-723页

作者： XIA Jun1, 2. wang Gangsheng1, TAN Ge1, YE Aizhong2.& G. H. Huang3 1. Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic sciences and Natural {2. Research, Chinese Academy of sciences, beijing 100101, China 2. State Key Laboratory of Water {2. & Hydropower Engineering sciences, Wuhan university, Wuhan 430072. China 3. faculty of Engineering, university of Regina, 3737 Wascana Parkway, Regina, Sask., S4S 0A2. Canada Correspondence should be addressed to Xia Jun Key Laboratory of Water Cycle & Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing China State Key Laboratory of Water resources & Hydropower Engineering sciences Wuhan University Wuhan China faculty of Engineering University of Regina Sask Canada

In this paper, a rainfall-runoff modeling system is developed based on a nonlinear Volterra functional series and a hydrological conceptual modeling approach. Two models, i.e. the time-variant gain model (TVGM) and the distributed time-variant gain model (DTVGM) that are built on the platform of Digital Elevation Model (DEM), Remote Sensing (RS) and Unit Hydro-logical Process were proposed. The developed DTVGM model was applied to two cases in the Heihe River Basin that is located in the arid and semiarid region of northwestern China and the Chaobai River basin located in the semihumid region of northern China. The results indicate that, in addition to the classic dynamic differential approach to describe nonlinear processes in hy-drological systems, it is possible to study such complex processes through the proposed sys-tematic approach to identify prominent hydrological relations. The DTVGM, coupling the advan-tages of both nonlinear and distributed hydrological models, can simulate variant hydrological processes under different environment conditions. Satisfactory results were obtained in fore-casting the time-space variations of hydrological processes and the relationships between land use/cover change and surface runoff variation.

关键词： hydrological process, nonlinearity, time-variant gain model, distributed hydrological model.

Evidence for metasomatic mantle carbonatitic magma extrusion in Mesoproterozoic ore-hosting dolomite rocks in the middle Kunyang rift, central Yunnan, China

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Progress in Natural Science:Materials International 2008年第8期18卷 965-974页

作者： Yongbei Zhanga,b,c, Hua Bia,*, Longshi Yua, Shihua Sunc, Jiaxiang Qiub, Chengyan Xub, Hao wang b, Renjing wang b a The Department of {2., Environment and Tourism, Hainan Normal university, No. 432. Yinpo Road, Longshepo, Haikou 57000, China b Key Laboratory of mineral {2., Institute of Geology and Geophysics, Chinese Academy of sciences, beijing 10002., China c faculty of earth sciences, China university of {12., Wuhan 470074, China The Department of resources Environment and Tourism Hainan Normal University No. 432 Yinpo Road Longshepo Haikou 57000 China Key Laboratory of mineral resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China faculty of earth {2. China University of Geosciences Wuhan 470074 China

The Kunyang rift lying on the western margin of the Yangtze platform is a rare Precambrian Fe-Cu mineralization zone. WudingLufeng basin that is an important part of the zone is located on the west edge in the middle of the rift. The most important ore-hosting rocks are Mesoproterozoic dolomite rocks in the basin controlled by a ring fracture system, which is a fundamental structure of the basin. Plenty of silicate minerals and acicular apatite, feldspar phenocrysts and small vesicular, flown line and flown plane structures, melt inclusion and high temperature fluid inclusion found in most ore-hosting dolomites suggest that this kind of rocks could not be sedimentary dolomite, marble or hydrothermal carbonate rocks. The Zr/Hf and Nb/Ta values of the rocks are identical with those of associated mantle-derived rocks, and vary widely. For the monomineral dolomite, d18OSMOW‰ = +5.99 to +18.4 and d13CPDB‰ = à3.01 to +0.94, which fall within the range for all carbonatitic volcanic rocks of the world. As for the accessory minerals, the values of d18OSMOW‰ of magnetite (=+3.47 to +5.99‰) are close to that of the mantle (2.2., and the calculated ISr = 0.699143, while for the associated mantle-derived rocks, eNd = +3.18 to +3.72. All the data suggest that the mineral assemblage is not only igneous but also of metasomatic mantle origin. And the presence of acicular apatite indicates that the rocks were formed by magma rapidly cooling. And the phenocryst texture and vesicular, flown and ropy and pyroclastic structures suggest that the igneous rocks were extrusive. Therefore, the ore-bearing dolomite rocks are carbonatitic volcanic rocks. This conclusion implies that most iron and copper ore deposits hosted in the dolomite rocks should be of the carbonatite type.

关键词： Central Yunnan Kunyang rift Precambrian mineralization Carbonatitite Volcanic rocks Petrogenesis Iron and copper ore deposit

Crust-Mantle Structure and Coupling Effects on mineralization:An Example from Jiaodong Gold Ore Deposits Concentrating Area,China

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Crust-Mantle Structure and Coupling Effects on Mineralizatio...

Geochronology and Petrogenesis of Late Carboniferous to Early Permian Basalts in the Central Lhasa Subterrane, Southern Tibet: Implications for the Evolution of the Sumdo Paleo-Tethys Ocean

中国科学院地质与地球物理研究所2.03学术年会

作者： Yang Liqiang Institute of Geology and Geophysics,Chinese Academy of sciences,beijing 100101 Deng Jun {2. of earth sciences and mineral resources,China university of geosciences,beijing 100083 Zhang Zhongjie wang Guangjie Institute of Geology and Geophysics,Chinese Academy of sciences,beijing 100101 wang Jianping {2. of earth sciences and mineral resources,China university of geosciences,beijing 100083

Based on the results of two-dimension velocity structure,1:100 000 aeromagnetic anomaly, 1 2.0 000 bouguer gravity anomaly and seismic anisotropy of Jiaodong and neighboring region in Shandong,China,the information of geophysical field was divided into two parts:deep- and shallow-focus *** then,the information of two different fields was combined with that of deep-seated geology and ore deposit *** synthetic result was adopted to analyze three-dimension structure,to probe into crust-mantle coupling effects of mineralization and dynamics of ore formation system.

关键词： geophysical field crust-mantle structure coupling effect dynamics of mineralization Jiaodong area of China

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Acta Geologica Sinica(English Edition) 2024年第4期98卷 955-968页

作者： MA wang LIU Yingchao YANG Zhusen Jan-Marten HUIZENGA LI Zhenqing YUE Longlong ZHAO Sibo School of earth sciences and {2. China University of GeosciencesBeijing 100083China Institute of Geology Sinoprobe LaboratoryChinese Academy of Geological SciencesBeijing 100037China MLR Key Laboratory of Metallogeny and mineral Assessment Institute of Mineral ResourcesChinese Academy of Geological SciencesBeijing 100037China faculty of Environmental sciences and Natural Resource Management Norwegian University of Life SciencesNO-1432ÅsNorway Economic Geology Research Centre(EGRU) College of Science and EngineeringJames Cook UniversityTownsvilleQueensland 4811Australia Department of Geology University of JohannesburgAuckland Park 2006South Africa

Basalts from the Late Carboniferous to Early Permian are extensively developed in the central Lhasa subterrane, southern Tibet. Studying the petrogenesis of these rocks may have implications for the late Paleozoic arc magmatism along the central Lhasa subterrane uncovering more of the evolution of the Sumdo Paleo-Tethys Ocean and its dynamic mechanism. Basalt samples from the Luobadui Formation in the Leqingla area, NW of Linzhou City in the central Lhasa subterrane, southern Tibet exhibit arc-like geochemical signatures in a subduction-zone tectonic setting characterized by high Al_(2.O_(3) and low TiO_(2. contents, fractionated REE patterns with low Nb/La ratios and high LREE concentrations, and negative HFSE anomalies. Based on their higher Th/Ce, Nb/Zr, and lower Ba/Th, Pb/Nd ratios, slightly negative to positive ε_(Nd)(t) values, and the relatively high Sr-Pb isotopic compositions, these samples were probably derived from partial melting of a depleted mantle source of garnet + spinel lherzolite, metasomatized by subducted sediments around 2.7 Ma. Modeling of the trace elements indicates that these basalts experienced fractional crystallization of olivine, clinopyroxene and minor plagioclase during magma ascent and eruption. It is proposed that these Late Carboniferous–Early Permian basalts are associated with the northward subduction of the Sumdo Paleo-Tethys Ocean seafloor along the southern margin of the central Lhasa subterrane.

关键词： geochemistry northward subduction Sumdo Paleo-Tethys Ocean Lhasa terrane Tibet

Boosting spring runoff into the sea by reservoir regulation and its potential for estuarine fishery recovery

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Science China earth sciences 2024年第5期67卷 1591-1603页

作者： Xiao WU Houjie wang Yongyong FAN Naishuang BI Chiyuan MIAO Jingping XU Zuosheng YANG College of Marine geosciences Key Laboratory of Submarine Geosciences and Prospecting Technologyand Frontiers Science Center for Deep Ocean Multispheres and Earth SystemOcean University of ChinaQingdao 266100China Laoshan National Laboratory Qingdao 266061China Institute of the Yellow River Estuary and Coast Science Dongying 257000China State Key Laboratory of earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijing 100875China Department of Ocean Science&Engineering Southern University of Science and TechnologyShenzhen 518055China

With global surge in reservoir construction over the past decades,river systems worldwide have been profoundly ***,flow manipulation by reservoirs has altered the natural hydrological processes,resulting in extensive modifications of fluvial-marine *** the adverse ecological consequences of reservoirs has become a global concern and has garnered increasing *** Yellow River,as one of the most extensively manipulated river systems globally,has experienced substantial changes in the amount and timing of water discharge due to the presence of numerous reservoirs scattered throughout its catchment *** alterations have caused physicochemical changes in the estuary and subsequent modifications to the estuarine *** recent years,the Yellow River Conservancy Committee initiated the release of water through the Xiaolangdi Dam during the major spawning period of fisheries,specifically in the spring,with the aim of improving the estuarine ecological *** 2.11 to 2.2.,a total of 84.05 km^(3)of water was discharged from the Xiaolangdi Reservoir during spring seasons,of which 40%(33.16 km^(3))constituted water impounded within the reservoir during preceding ***,the spring water discharge from the Yellow River to the sea increased significantly from 1.50 km^(3)/yr to 3.46 km^(3)/yr in the past decade,leading to a decrease in estuarine salinity by 1.6 *** estuarine fishery resources,such as fish eggs in the Yellow River estuary,have demonstrated evident *** reservoir regulation in the Yellow River,which has successfully enhanced spring water discharge and subsequently restored estuarine fishery resources,presents an effective attempt for mitigating the adverse ecological effects associated with reservoirs.

关键词： Reservoir regulation Water release Spring runoff Estuarine ecosystem Yellow River

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Discussion on The Geobarmal Gradient in Orogenic Belt and the Metamorphysism Caused by Ultra-high-pressure

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Discussion on The Geobarmal Gradient in Orogenic Belt and th...

Annelid from the Neoproterozoic Doushantuo Formation in Northeastern Guizhou,China

地壳深部压力状态与地质作用学术研讨会

作者： Fangzheng wang Baoqun Hu Guxian Lv Ruixun Liu faculty of {2. sciences in China university of geosciences (Wuhan 430074) East China Institute of Technology (Jiangxi 344000) Research Institute of geology and mechanics in the Ministry of Land and resources (beijing 100081) School of the {2. and Space sciences,Peking university (beijing 100871)

＜正＞ 1. Research Review （Introduction） The geobarmal gradient and geothermal gradient are two important function variables thatreflect the physical and chemical state of lithosphere, respectively. Geothermal gradient refers tothe variability of the temperature in different lithosphere depth. So it is also called geothermal degree, which shows the lithosphere temperature that changes with its depth. However, geobarmal gradient refers to the variability of the pressure in different lithosphere depth, which reflects the mechanic （pressure） state of lithosphere that changes with its depth. It is also called the pressure

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Acta Geologica Sinica(English Edition) 2008年第2期82卷 257-265页

作者： wang Yue wang {2. School of earth sciences and {2. China University of Geosciences Beijing 100083 China School of resources and Environment Guizhou University Guiyang 550003 China

Wenghuiia jiangkouensis gen. et sp. nov., characterized by modern annelid taxonomy in morphology and functional biology, is found in black carbonaceous shale from the Neoproterozoic Ediacaran Doushantuo Formation （about 555 Ma） near Wenghui, Jiangkou, northeastern Guizhou Province. The elongate, cylindrical body is composed of many homologous metameres with a true coelom and coelomic pouches. The mouth is at the front of the first segment and the anus at the end of body. A long 11th or 12.h segment is probably functionally for procreation, being a clitellum. There are parapodia on the venter of the segments from the rear of the second segment to the front of the clitellum. The setae on all metameres, on the parapodia, and around the anus, differ. In the centre of body, a line probably represents the alimentary canal passing through the body from mouth to anus. A closed vascular system consists of a dorsal vessel at least. W. jiankouensis might represent the oldest discovered ＇modern＇ annelid but it is not a primitive type. It lived on the depositional surface of a shallow sea with an environment of calm-water and abundant light.

关键词： annelid Doushantuo Formation Neoproterozoic northeast Guizhou China

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“金钉子”之后的国际年代地层表刍议

科学通报 2022年第3期67卷 307-320页

作者：王训练中国地质大学(北京)地球科学与资源学院北京100083

国际年代地层表是地质学研究的一个纲领性文献,为地质学研究提供了时间格架,对现代地质学的诞生和发展作出了重要贡献.关于用生物标志还是用事件标志定义年代地层界线的争议由来已久.2.世纪70年代以前主要以"自然事件"作为年代地层单位... 详细信息

国际年代地层表是地质学研究的一个纲领性文献,为地质学研究提供了时间格架,对现代地质学的诞生和发展作出了重要贡献.关于用生物标志还是用事件标志定义年代地层界线的争议由来已久.2.世纪70年代以前主要以"自然事件"作为年代地层单位的划分依据,界线一般都选择在发生某些地质事件的位置上,即"自然界线"或"发生过事件"的界线[1,2..这种方法注重自然界线,重视各类地层单位之间的普遍联系和统一性.其不足之处在于忽视了事物普遍联系的多样性和不同类型地层单元界线之间的本质差别,忽视了一些地质事件发生非等时性、分布的区域性和表现的多样性,不恰当地用代表时间间断的沉积不连续面等自然界线定义年代地层界线,使年代地层界线和地质年代表无法稳定,因而受到后来许多学者的强烈反对.

关键词：地质年代表年代地层单位事件标志地质学研究普遍联系不连续面自然界线生物标志

Macroalgal holdfasts and their interaction with environments from the Neoproterozoic Doushantuo Formation in Guizhou,South China

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Frontiers in Biology 2008年第1期3卷 113-122页

作者： Yue wang xunlian wang School of earth sciences and {2. China University GeosciencesBeijing 100083China School of resources and Environments Guizhou UniversityGuiyang 550003China

Numerous macro-organisms of the Doushantuo macrobiota,which were found in the black carbonaceous mudstone of the upper Neoproterozoic Ediacraan Doushan-tuo Formation in Jiangkou County,Guizhou Province,China,are considered to live on sea floor by their *** appearance and preserved forms of the macroalgal holdfasts may provide some data to the study of the living and buried environments of *** lived in the lower energy and clear environment,and fixed on a soupground with rich water(about 79%water).Currents,possibly ocean currents,could pull out the macroalgal holdfasts from the soupground and break off the macroalgal *** such events,the corpses of macro-organisms would be covered in a reduced environment by the ***,a new community,including regenerating and undying macro-organisms,lived continuously on a new deposit.

关键词： holdfast macroalgae Doushantuo Formation Neoproterozoic Ediacaran Jiangkou Guizhou China