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Vegetation NPP Distribution Based on MODIS Data and CASA Model——A Case Study of Northern Hebei Province 被引量:19
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作者 YUAN Jinguo NIU Zheng WANG Chenli 《Chinese Geographical Science》 SCIE CSCD 2006年第4期334-341,共8页
Net Primary Productivity (NPP) is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial a... Net Primary Productivity (NPP) is one of the important biophysical variables of vegetation activity, and it plays an important role in studying global carbon cycle, carbon source and sink of ecosystem, and spatial and temporal distribution of CO2. Remote sensing can provide broad view quickly, timely and multi-temporally, which makes it an attractive and powerful tool for studying ecosystem primary productivity, at scales ranging from local to global. This paper aims to use Moderate Resolution Imaging Spectroradiometer (MODIS) data to estimate and analyze spatial and temporal distribution of NPP of the northern Hebei Province in 2001 based on Carnegie-Ames-Stanford Approach (CASA) model. The spatial distribution of Absorbed Photosynthetically Active Radiation (APAR) of vegetation and light use efficiency in three geographical subregions, that is, Bashang Plateau Region, Basin Region in the northwestern Hebei Province and Yanshan Mountainous Region in the Northern Hebei Province were analyzed, and total NPP spatial distribution of the study area in 2001 was discussed. Based on 16-day MODIS Fraction of Photosynthetically Active Radiation absorbed by vegetation (FPAR) product, 16-day composite NPP dynamics were calculated using CASA model; the seasonal dynamics of vegetation NPP in three subreglons were also analyzed. Result reveals that the total NPP of the study area in 2001 was 25.1877 × 10^6gC/(m^2.a), and NPP in 2001 ranged from 2 to 608gC/(m^2-a), with an average of 337.516gC/(m^2.a). NPP of the study area in 2001 accumulated mainly from May to September (DOY 129-272), high NIP values appeared from June to August (DOY 177-204), and the maximum NPP appeared from late July to mid-August (DOY 209-224). 展开更多
关键词 NPP distribution MODIS data CASA model northvrn hebei province
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Studies on Water Consumption Characteristics and Crops Rotation Effects in Plateau of Northern Hebei Province
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作者 ZHANG Li-feng, BIAN Xiu-ju and LIU Yu-hua(Hebei Agricultural University, Bonding 071001 ) 《Agricultural Sciences in China》 CAS CSCD 2002年第1期76-80,共5页
Experiments were carried out in 1994 - 1998 to study crop rotation and its effects on crop water consumption characteristics of field with sandy chestnut soil in the Plateau of north Hebei Province. Five crops includi... Experiments were carried out in 1994 - 1998 to study crop rotation and its effects on crop water consumption characteristics of field with sandy chestnut soil in the Plateau of north Hebei Province. Five crops including spring wheat, oat, pea, flax and potato were examined. There was little difference in field water consumption among the crops during the growing season. WUE varied significantly in a range of 1. 347 -11.177kg · ha-1 · mm-1 among crops and 11.44% - 46.66% among previous crops. It was pointed out that the land equivalent ratio (LER) can be used as an index to evaluate the biological effects of crop rotation comprehensively. The 2-4 year crop rotation patterns with higher LER were estimated in the paper. 展开更多
关键词 ROTATION Water consumption WUE LER Plateau of north hebei province
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Effects of Different Modes of Returning Farmland to Forest on Physicochemical Properties of Soil in Bashang Area of Northern Hebei Province
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作者 Yue YANG Yitian YANG +2 位作者 Zhiyong WU Caiwu WU Yongjiao HAN 《Meteorological and Environmental Research》 CAS 2020年第4期98-102,共5页
[Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three differe... [Objective]The research aimed to understand the change rules of physicochemical properties of soil in the different modes of returning farmland to forest.[Method]The physicochemical properties of soil in three different types of returning farmland to forest(Hippophae rhamnoides Linn.forest,Caragana korshinskii forest and Ulmus pumila L.forest)were analyzed by taking the enclosed grassland as comparison in Bashang area of northern Hebei Province.[Result]The results showed that there were significant differences among different types.Order of the bulk density of soil:H.rhamnoides Linn.forest(1.17 g/cm^3)<U.pumila L.forest(1.24 g/cm^3)<C.korshinskii forest(1.26 g/cm^3)<enclosed grassland(1.61 g/cm^3);order of the total porosity of soil:H.rhamnoides Linn.forest(55.29%)>U.pumila L.forest(52.55%)>C.korshinskii forest(51.93%)<enclosed grassland(38.85%);order of the organic matter content of soil:H.rhamnoides Linn.forest(3.191%)>C.korshinskii forest(3.128%)>U.pumila L.forest(2.804%)>enclosed grassland(2.536%).[Conclusion]After returning farmland to forest,vegetation played a positive role in physicochemical properties of soil.There were significant differences in physicochemical properties of soil among different modes of returning farmland to forest,and the improvement effect of H.rhamnoides Linn.forest on physicochemical properties of soil was the best. 展开更多
关键词 Returning farmland to forest Physicochemical properties of soil Bashang area of northern hebei province
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Application of the Stress Evolutionary Model in Hebei Province,North China
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作者 Zhang He Karakostas V. G. +2 位作者 Papadimitriou E. E. Lv Guojun Jin Xueshen 《Earthquake Research in China》 2013年第2期233-249,共17页
Coulomb stress changes associated with strong earthquakes occurring since 1484 in Hebei Province,China are investigated. The North China block has had many large historical earthquakes and some damaging earthquakes in... Coulomb stress changes associated with strong earthquakes occurring since 1484 in Hebei Province,China are investigated. The North China block has had many large historical earthquakes and some damaging earthquakes in the past century,including the 1976 Tangshan earthquake (M =7.8) . The study area and the adjacent areas of the province comprise the most active seismic fault zones and suffer from both strong and frequent events. The North China Block,which includes the Ordos plateau and the North China plain,is part of the Archean Sino-Lorean craton and one of the most active seismic regions in the world. Its movement is accommodated on major strike-slip intraplate fault zones that strike in the E-W direction. The faults in the study area contribute to the complexity of the stress field. Seismic hazard assessment in this region is attempted by calculating the change of the Coulomb failure function ( ΔCFF) arising from both the coseismic slip of strong events (MS≥6.5) and the stress built up by continuous tectonic loading on major regional faults. At every step of the stress evolutionary model an examination of possible triggering of each next strong event is made and the model finally puts in evidence that the fault segments that are apt to fail in an impending strong event,thus providing future seismic hazard evaluation. In this paper,the results of ΔCFF for Zhangjiakou fault, Xiadian fault and Langfang fault have been shown as examples to express the possiblity of generating future seismic hazard. 展开更多
关键词 Coulomb stress Application Stress Evolutionary Model hebei province
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Discussion on the Prevention and Control Countermeasures of Sudden Disasters on Protected Vegetable in Hebei Province 被引量:1
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作者 刘云 梁玉芹 +1 位作者 王灵敏 宋炳彦 《Agricultural Science & Technology》 CAS 2016年第3期511-515,共5页
Protected vegetable production made the traditional agriculture gradually get rid of the shackles of nature, broke the seasonal traditional agriculture and realized the anti season list of agricultural products. While... Protected vegetable production made the traditional agriculture gradually get rid of the shackles of nature, broke the seasonal traditional agriculture and realized the anti season list of agricultural products. While protected vegetables often encountered sudden disasters in production and were restricted with the conditions of low temperature and weak light. Aimed at the sudden disasters of protected vegetable production in Hebei Province,the countermeasures for disaster prevention and control were put forward from the aspects of variety selection, seedling treatment technology,grafting technique,cultivation and management,flower and fruit retention technology,application of exogenous substance,rational fertilization,transgenic technology and so on,in order to reduce production risks and cut loss,realize that protected vegetable production is safe,good-quality and efficient. 展开更多
关键词 hebei province Protected vegetable Sudden disasters Prevention and control countermeasures
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Magmatic Event at the End of the Archean in Eastern Hebei Province and Its Geological Implication 被引量:91
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作者 GENG Yuansheng LIU Fulai YANG Chonghui 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第6期819-833,共15页
By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ... By using the SHRIMP U-Pb and single zircon stepwise evaporation methods, the authors have obtained some results for granitoids from eastern Hebei Province. The Yuhuzhai hyperthene tonalitic granite was formed 2550 Ma ago, the Qingyangshu gabbroic gneiss 2536 Ma, the Yinmahe granodioritic gneiss near Lücao, Lulong County, 2533 Ma, the gabbro-dioritic gneiss near Longwan, Qianxi County, 2518-2515 Ma, the Qiuhuayu trondjemitic gneiss at Zunhua 2515 Ma, the Xiaoguanzhuang tonalitic gneiss at Zunhua 2495 Ma, and the Cuizhangzi gneiss in Qianxi County 2492 Ma. These geochronilogical data demonstrate that, though diverse in composition, type and origin, the granitic gneisses in eastern Hebei Province were emplaced and crystallized in a rather short period of magmatic activity. The formation of such a great amount of gneisses in this small time gap suggests that it was a critical crust accretion stage at the end of Neoarchean. The fact that granitoids of various types occurred at the same time implies a large-scale underplating (mantle plume) activity, which was then responsible for the crust accretion. 展开更多
关键词 ORTHOGNEISS magmatic event NEOARCHEAN zircon age eastern hebei province
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A New Enantiornitine Bird with Four Long Rectrices from the Early Cretaceous of Northern Hebei,China 被引量:12
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作者 ZHENG Xiaoting ZHANG Zihui HOU Lianhai 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2007年第5期703-708,共6页
Paraprotopteryx gracilis, a new enantiornithine bird from the Early Cretaceous Yixian Formation in Fengning, northern Hebei Province is erected, based on the following characters: Yshaped furcula with a long hypoclei... Paraprotopteryx gracilis, a new enantiornithine bird from the Early Cretaceous Yixian Formation in Fengning, northern Hebei Province is erected, based on the following characters: Yshaped furcula with a long hypocleidum and a much narrow interclavicular angle, and the morphology of the sternum are different from other enantiornithines. Additionally, alular digit bearing the biggest manual claw extends distally to the distal end of the major metacarpal; the minor metacarpal is slender than the major metacarpal. Carpometacarpus only fused proximally; astragalus and calcaneum partially fused to one another but unfused to the tibia. This is the first record of Mesozoic birds in having four long rectrices, which may represent morphologically a secondary sexual character, an intermediate stage from elongated scale to branched feather, and possess functional advantage in supplementing the lifting surface to compensate the unskilled flight. 展开更多
关键词 Early Cretaceous Paraprotopteryx gracilis enantiornithine rectrices Fengning hebei province
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Process and mechanism of arable land change in Hebei Province during the past 50 years 被引量:3
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作者 XU Yue-qing (Institute of Geographical Sciences and Natural Resources Research, CAS, Beijing 100101, China College of Resource and Environment Science, Hebei Normal University, Shijiazhuang 050016, China ) 《Journal of Geographical Sciences》 SCIE CSCD 2001年第4期47-52,共6页
Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with pop... Hebei Province is one of the regions with most densely population, fastest economic growth and most intensive land use in China. The contradiction of land shortage sharpened by high-speed economic development with population growth has become a serious problem, which has restricted regional sustainable development.This paper revealed the basic process, regional differences of change and the gravity center of arable land area according to the long-series statistical data of arable land during the past 50 years. On the basis of the above mentioned, the major driving forces that influence the changes of the arable land are discussed. The research results indicate that there is a trend of obvious fluctuating decrease in arable land area during the last 50 years. The changes of arable land area undergo the process from increase to sharp decrease to gently decrease. The regional disparity of change in arable land area is very notable and the gravity center of arable land area moves to the northeast 49.22 km. Regarding the decrease in arable land, the direct driving forces include adjustments of agricultural structure and reclamation, and indirect driving forces include advance in technology, economic interest and population growth etc. 展开更多
关键词 decrease in arable land area changing process mechanism hebei province
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Observations of coastal aeolian dune movements at Feicuidao, on the Changli Gold Coast in Hebei Province 被引量:3
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作者 YuXiang Dong DeQuan Huang JianHui Du 《Research in Cold and Arid Regions》 CSCD 2013年第3期324-330,共7页
High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei... High-precision RTK GPS technology was used to survey the movements of typical coastal dunes, including a coastal crescent dune and a coastal transverse ridge, in the Feicuidao region of the Changli Gold Coast in Hebei Province in 2006-2008. Our data provide information on the direction, type, and velocity of coastal dune movements, and indicate that the coastal dunes in this re- gion are characterized as slow and landward advancing, with to-and-fro fluctuations. The bottom of the studied coastal transverse ridge was stable during the observation period but the position of its crest advanced eastward (seaward) during summer and au- tumn, and moved landward (westward) in winter and spring. Thus, its crest moved generally landward (westward) but fluctuated to-and-fro eastward and westward. In contrast, the entire coastal crescent dune advanced landward (westward) in a to-and-fro manner, and the velocity of its movement was faster than that of the transverse ridge dune. These results are mainly related to the wind conditions in the research area, the height and volume of the two types of coastal dunes. 展开更多
关键词 coastal dune MOVEMENT observation Changli in hebei province
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Response to Hydrothermal Change of Tree Radial Growth since 1990s in the Southern Taihang Mountains in Hebei Province 被引量:1
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作者 Yajun WANG 《Agricultural Science & Technology》 CAS 2016年第12期2826-2827,2833,共3页
On the basis of the relationship between tree ring width of Pinus tabulaeformis in the southern Taihang Mountains in Hebei Province and climate factors, such as mean temperature, mean maximum temperature, mean minimum... On the basis of the relationship between tree ring width of Pinus tabulaeformis in the southern Taihang Mountains in Hebei Province and climate factors, such as mean temperature, mean maximum temperature, mean minimum temperature and precipitation, we find that tree-ring width correlates positively and significantly with mean and maximum temperature in March and Spring, and with minimum temperature in March, April, Spring and Autumn. The sampling tree radial growth responds sensitively to spring temperature change. 展开更多
关键词 SOUtheRN Taihang MOUNTAINS in hebei province TREE radial growth HYDROtheRMAL condition
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Evaluation of the Overall Level of New Urbanization in Hebei Province Based on Factor Analysis and GIS 被引量:1
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作者 Shuqin ZHAO Xuemeng SHI Yunfan NIU 《Asian Agricultural Research》 2014年第9期44-49,共6页
Urbanization is the result of economic and social development,but also an important indicator to measure the level of regional economic and social development. Since the reform and opening up,the level of urbanization... Urbanization is the result of economic and social development,but also an important indicator to measure the level of regional economic and social development. Since the reform and opening up,the level of urbanization in Hebei province has been lagging behind the national average level. The 18 th National Congress of the CPC proposed to develop new urbanization,and this paper evaluated the comprehensive urbanization level of Hebei province combined with new connotation of urbanization. It constructed an evaluation index system of Hebei Province's urbanization comprehensive level,and then used the method of factor analysis with SPSS statistical analysis software to distinguish the major influencing factors. Thirdly,it overlaid the result with spatial pattern,which calculated by the spatial visualization function of ArcGIS software,making the evaluation results presented in a more vivid way. Finally,it analyzed the driving factors of urbanization development in Hebei Province and put forward some suggestions. 展开更多
关键词 New URBANIZATION FACTOR analysis GIS hebei Provinc
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Application of the Gravity Method to the Iron Ore Exploration in Eastern Hebei Province 被引量:5
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作者 ZHANG Guoli ZHAO Gengxin +3 位作者 HE Fuqing SU Yongjun TENG Fei KUANG Haiyang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2015年第6期2097-2098,共2页
The nation-wide iron ore exploration is primarily based on aeromagnetic survey,based upon which a series of ground follow-up and drilling examination were carried out,and then reconnaissance and detailed investigation... The nation-wide iron ore exploration is primarily based on aeromagnetic survey,based upon which a series of ground follow-up and drilling examination were carried out,and then reconnaissance and detailed investigation and exploration were fulfilled.However,for some large. 展开更多
关键词 Application of the Gravity Method to the Iron Ore Exploration in Eastern hebei province
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Study on the Vegetable Brand Construction in Hebei Province Based on Agricultural Supply Side Structural Reform 被引量:1
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作者 Chunfeng ZHANG Xiao ZHANG +3 位作者 Haichen SUN Jian SONG Wenqi DONG Muqiang HU 《Agricultural Science & Technology》 CAS 2017年第10期1989-1992,共4页
Strengthening brand construction should be the starting point for the development of vegetable industry, and the key point of upgrading quality, enhancing efficiency and transforming the development pattern in Hebei P... Strengthening brand construction should be the starting point for the development of vegetable industry, and the key point of upgrading quality, enhancing efficiency and transforming the development pattern in Hebei Province. In view of the current situation of vegetable industry in Hebei Province, such as market saturation, quality upgrading, and the problems existing in the development of vegetable brands, some ideas and suggestions were put forward to strengthen the development of brand vegetables in Hebei Province. 展开更多
关键词 VEGETABLE Supply-side reform BRAND hebei province
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The Isotopic Composition of Noble Gases in Gold Deposits and the Source of Ore-Forming Materials in the Region of North Hebei, China 被引量:9
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作者 王宝德 牛树银 +1 位作者 孙爱群 李红阳 《Chinese Journal Of Geochemistry》 EI CAS 2003年第4期313-319,共7页
The source of ore\|forming materials has long been a controversial focus both in metallogenic theory and in ore\|searching practice. This study deals with the helium and argon isotopic characteristics of pyrites from ... The source of ore\|forming materials has long been a controversial focus both in metallogenic theory and in ore\|searching practice. This study deals with the helium and argon isotopic characteristics of pyrites from 11 gold deposits and some country rocks in the gold mineralization\|concentrated areas within the three mantle\|branch structures in the region of North Hebei Province. It is indicated that \{\}\+3He/\+4He ratios in the gold deposits are within the range of \{0.93×10\+\{-6\}\}-\{7.3×10\+\{-6\}\}, with an average of \{3.55\} ×10\+\{-6\}; R/Ra=\{0.66\}-\{4.93\}, averaging \{2.53\}; \{\{\}\+\{40\}Ar/\+\{39\}Ar\} ratios vary between 426 and 2073, with the average value of \{\}\+\{40\}Ar being \{8.32\}; and the average of \{\}\+4He/\{\}\+\{40\}Ar ratios is 2.17. \{\}\+3He/ \{\}\+4He ratios in gneiss and granite in the periphery of the mining district are within the range of \{0.001×10\+\{-6\}\}-\{0.55×10\+\{-6\}\}, reflecting significant differences in their sources. \{\}\+3He and \{\}\+4He fall near the mantle, as is shown in the He concentration diagram. Studies have shown that the ore\|forming materials in this region should come from the deep interior of the Earth. With the multi\|stage evolution of mantle plume, ore\|forming fluids in the deep interior were moving upwards to shallow levels (crust). Under such circumstances, there would be inevitably occur crust/mantle fluid mixing, so their noble gas isotopic characteristics are intermediate between the mantle and the crust. 展开更多
关键词 gold DEPOSIT source of 0re-forminE nmterial He Ar ISOTOPIC composition mantle-branch structure MANTLE PLUME
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Empirical research on impacted factor of farmer's willingness for purchasing information Based on the survey data of Hebei province 被引量:1
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作者 SUN Gui-zhen LI Ya-qing 《Chinese Business Review》 2009年第10期58-63,共6页
Farmer's willingness for purchasing information, an important factor of farmer's information demand, was analyzed by logit model, according to the survey data of 535 farmers from eleven cities in Hebei province. The... Farmer's willingness for purchasing information, an important factor of farmer's information demand, was analyzed by logit model, according to the survey data of 535 farmers from eleven cities in Hebei province. The result showed that 6 factors had a significant influence on it, that is, education of farmers, per capita income of farmers, the affordability of information risk, the proportion of agricultural labor households, the type of agricultural production and the rural information service stations. On the basis of these, the related policy recommendations were proposed. 展开更多
关键词 FARMER willingness for purchasing information empirical analysis hebei province
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Tectonic Environments of the Yan-Liao Rift during Earth's Middle Age(1.7~0.75 Ga): Evidence from Mafic Dyke Swarms in Eastern Hebei, North China 被引量:1
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作者 WANG Chong PENG Peng +1 位作者 WANG Xinping YANG Shuyan 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期45-46,共2页
During the past decade,generations of Precambrian mafic dykes/sills have been investigated and revealed in the North China Craton(NCC).Researchers identified more than 20 episodes of Precambrian dyke swarms,
关键词 north China Tectonic Environments of the Yan-Liao Rift during Earth’s Middle Age Evidence from Mafic Dyke Swarms in Eastern hebei Ga
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Source of ore-forming material for the Huangtuliang gold deposit,Hebei Province and ore prospecting in the deep periphery 被引量:4
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作者 NIU Shuyin SUN Aiqun +6 位作者 WANG Baode HAN Yuchou WEI Minghui ZHANG Hai ZHANG Ge SHI Ping WANG Wenxing 《Chinese Journal Of Geochemistry》 EI CAS 2008年第3期225-234,共10页
The Huangtuliang gold deposit is characterized by its wide and large ore belt,stable extension and closely spaced orebodies.Unfortunately,no orebody was found by deep drilling.As a result,ore prospecting in this regio... The Huangtuliang gold deposit is characterized by its wide and large ore belt,stable extension and closely spaced orebodies.Unfortunately,no orebody was found by deep drilling.As a result,ore prospecting in this region was once put into dilemma.Detailed analysis of ore-forming and ore-controlling structures in the mining district by the authors has revealed that the ore-forming and ore-controlling structure in this mining district is a steeply dipping(85°-110°/∠70°-85° N-NNE),spade-shaped ductile shear zone,and the ore-controlling structures are a series of nearly erected second-ordered faults which are developed in the upper part of the ductile shear zone,intersecting with the ductile shear zone.Deep cutting of the ductile shear zone made it possible the ascending of ore fluids from the mantle plume at depth and these ore fluids would migrate upwards along the ductile shear zone under certain temperature and pressure conditions.Along their ascending path,the ore fluids would extract ore-forming elements from the country rocks and the extracted ore-forming elements would be deposited as ores in the hanging-wall second-ordered faults.The reason why no orebody was found in early prospecting at depth is that northward-dipping drilling in the southern part of the shear zone extended so deeply as to be beneath the shear zone.Only shallow-level orebodies could be found by southward-dipping drilling practice in the northern part of the shear zone.The location where deep-seated orebodies occurred shifted northwards and the orebodies occurred at greater depth.Therefore,it is natural that no orebody could be found when drill core passed through the shear zone.After the ore-forming and ore-controlling structures were well understood,the focus of ore prospecting was placed on the deep-level,northward-penetrating veins.In this way a number of new blind orebodies of great thickness have been found.On the basis of research development in the mining district,a prospecting plan has been made for ore prospecting in the periphery of eastern mining district.Prospecting practice has shown that there occur generally continuous engineering orebodies at large intervals.So,the Huangtuliang gold deposit has turned at one stroke from a medium sized to a large-sized,even a super-large gold deposit between prospecting lines 30-98. 展开更多
关键词 地幔分支结构 地幔热流柱 矿石 河北
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Analysis of the Influencing Factors of Changes in Foxtail Millet Planting Area in Hebei Province 被引量:2
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作者 Meng LIU Yu ZHAO +3 位作者 Fei LIU Shunguo LI Guirong WANG Xinshi ZHANG 《Asian Agricultural Research》 2013年第3期30-34,共5页
Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In t... Since reform and open to the outside world,foxtail millet planting area in Hebei Province has constantly reduced,and its planting region has changed from the whole province into some regions,with obvious changes. In this paper,by using qualitative and quantitative approaches like chart analysis,summarizing,Delphi method and osculating value model,the influencing factors of changes in millet growing region in Hebei Province were studied. The results showed that the changes of millet planting area were closely related to many factors,such as little investment in scientific research,weak policy support,a single consumer product demand,the rapid development of other staple crops, labor migration,relatively low comparative effectiveness and physiological characteristics of the millet itself. Then some suggestions were put forward,such as increasing research support,strengthening scientific research strength,researching and developing deeply processed products, expanding consumer groups,improving millet policy support,providing subsidies for planting the improved varieties,researching and developing various types of machinery,and increasing millet production technology training. 展开更多
关键词 MILLET area CHANGES Influencing FACTORS Osculating
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Isotopic Characteristics of Mesozoic Au-Ag Polymetallic Ore Deposits in Northern Hebei and Their Ore-Forming Materials Source 被引量:3
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作者 王宝德 牛树银 +1 位作者 孙爱群 李红阳 《Chinese Journal Of Geochemistry》 EI CAS 2003年第3期203-214,共12页
It has long been a controversy about the source of ore\|forming materials of Au\|Ag polymetallic deposits both in metallogenic theory and in ore\|searching practice. In terms of a large wealth of the isotopic statisti... It has long been a controversy about the source of ore\|forming materials of Au\|Ag polymetallic deposits both in metallogenic theory and in ore\|searching practice. In terms of a large wealth of the isotopic statistics data from Indosinian\|Yanshanian endogenic ore deposits in northern Hebei (generally referring to the areas along the northern part of Taihang Mountains and northern Hebei, the same below), it is considered that the ore\|forming materials came from the deep interior of the Earth, which had migrated through plumes to the Earth surface while experienced multi\|stage evolution and then emplaced progressively in favorable structural loci to form ores. Their isotope data show that 559 sulfur isotopic data from 40 ore deposits are, for the most part, within the range of -5‰- 5‰, with a high degree of homogenization, indicating that the sulfur is derived mainly from magma; 200 lead isotope data from 37 ore deposits indicate that the ore\|forming materials are principally of mantle source though some crust\|source material was involved; 96 oxygen, hydrogen and carbon isotope data from 34 ore deposits illustrate that the ore\|forming fluids are dominated by magmatic water while other sources of water would be involved. It may therefore be seen that the formation of endogenic deposits has nothing to do with the strata . 展开更多
关键词 同位素特征 中生代 金-银多金属矿床 内生矿床 河北 Indosinian-Yanshanian周期 成矿
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Study on the ore-forming and ore-controlling structure of the Mujicun Cu (Mo) ore deposit, Hebei Province, China 被引量:2
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作者 NIU Shuyin MA Guoxi +8 位作者 CHEN Zhikuan WANG Baode CHEN Lijing SUN Aiqun MA Xiaofeng ZHANG Jianzhen MA Baojun CHEN Chao LU Hongpeng 《Chinese Journal Of Geochemistry》 EI CAS 2012年第1期1-14,共14页
The Mujicun Cu (Mo) ore deposit at Laiyuan, Hebei Province, is a currently proven large-sized Cu (Mo) polymetallic ore deposit and it is located in the second-ordered fault depression basin of the ditachment belt on t... The Mujicun Cu (Mo) ore deposit at Laiyuan, Hebei Province, is a currently proven large-sized Cu (Mo) polymetallic ore deposit and it is located in the second-ordered fault depression basin of the ditachment belt on the hanging-wall on the western side at the juncture of the Laiyuan dumbell-shaped complex in the northern part of the Fuping mantle-branch structure. Metallogenesis is controlled by diorite porphyrite in intrusive relation with the fault depression basin and other relevant fault structure systems and intenstive wall-rock alteration zones. This study, in conjunction with the most recent exploration data, analyzed the geological background of metallogenesis of this deposit, summaried the geological characteristics of typical ore deposits, determined the alteration zonation of the deposit, investigated regional metallogenesis and the genesis of typical ore deposits, discussed the regional ore-forming and ore-controlling structures, and generalized the regional ore-controlling model and metallogenic model of the deposit. It is considered that the Mujicun porphry Cu (Mo) deposit, the Tieling, Futuyu, Xiaoligou and other skarn-type Fe-Cu deposits and the He'ergou hydrothermal-type Pb-Zn-Ag deposit jointly constitute a three-in-one polymetallic orefield, with the characteristics of typical metallogenic series. 展开更多
关键词 多金属矿床 控矿构造 成矿控制 河北省 铜矿 中国 断裂构造系统
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