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Urban Spatial Form Optimization Strategies Based on the Principle of Climate Adaptability of Regional Architecture: A Case Study of Traditional Cave Dwelling Villages in Northern Shaanxi Province
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作者 QI Zizhuo YANG Xin 《Journal of Landscape Research》 2024年第3期1-7,共7页
A multitude of climate-adaptive design approaches are embedded in regional architecture,which have a positive impact on addressing the deformed development of urban spatial patterns and the dual challenges of climate ... A multitude of climate-adaptive design approaches are embedded in regional architecture,which have a positive impact on addressing the deformed development of urban spatial patterns and the dual challenges of climate and resources.This paper examines the principles of climate adaptability embedded in the site layout and spatial organization characteristics of traditional cave dwelling villages in northern Shaanxi Province.The extracted climate adaptability principles are summarized,and the resulting design strategies that are well-suited to the contemporary urban space form are presented.Through analysis,it can be observed that traditional cave dwelling villages in northern Shaanxi are predominantly situated on south-facing slopes in proximity to water at low altitudes.These villages are characterized by compact building groups and east-west development,which is constrained by the elements of mountains and rivers.A two-level street system is generated,comprising streets parallel to the contour line and roadways perpendicular to the contour line.This results in the formation of a courtyard form enclosed by mountains.Such site layout and spatial organization exhibit excellent climate adaptability with regard to heat,ventilation,and wind storage.In light of the aforementioned considerations,the following urban spatial form design strategies are put forth:①the topographic height difference can be exploited to obtain sufficient sunshine;②the group shape can be optimized in order to reduce building energy consumption;③the best orientation of the building can be chosen to take account of both winter and summer conditions;④the height and length can be combined in order to form natural masking;⑤the D/H ratio of streets and roadways should be controlled to achieve a balance between heat gain and cooling of groups;⑥vents should be set appropriately to optimize group ventilation;⑦climate buffers should be established to increase the level of climate response. 展开更多
关键词 Traditional cave dwellings in northern shaanxi Urban spatial form Outdoor thermal environment
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Dry Intrusion Analysis of A Heavy Rainstorm in Southern Shaanxi 被引量:2
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作者 刘瑞芳 郭大梅 +1 位作者 李萍云 侯建忠 《Meteorological and Environmental Research》 CAS 2010年第12期25-29,共5页
[Objective] One regional rainstorm weather in the south area of Shaanxi was expounded.[Method] By employing the NCEP/NCAR 1°×1°reanalysis data,routine observation and automatic precipitation station dat... [Objective] One regional rainstorm weather in the south area of Shaanxi was expounded.[Method] By employing the NCEP/NCAR 1°×1°reanalysis data,routine observation and automatic precipitation station data,the large scale circulation background field of regional precipitation in the south area of Shaanxi province from July 16-18 in 2010 was expounded.By dint of physical quantity such as the meridional wind,relative humidity and false relative temperature,the characteristics of dry intrusion and its role in rainstorm were expounded.[Result] The mild and high latitude at 500 hPa was stable.The continental high pressure and subtropical high pressure were stable.The 700 and 850 hPa shear lines or low vortexes were the main influence system that resulted into large scale of rainstorm in south Shaanxi.The landing typhoon had distinct influences on the importance of storm.The influence of typhoon and subtropical high was mutual.It not only formed and strengthened the torrent in the low air,also transmitted water vapor and energy incessantly to the south area of Shaanxi,playing an important role in augment of rainstorm.There were two distinct dry intrusions in the rainstorm process,showing a dense dry layer in the high layer of convective layer.The existence of dry layer was conductive to the accumulation of convective unstable energy in the low layer.The release of convective unstable energy could transmit warm and wet airstream in the low level to the higher level,being conductive to the occurrence of precipitation.The analysis of θse in the warp direction vertical profile suggested that there was frontal zone in this rainstorm process and the dry air activity in this rainstorm process was very strong.[Conclusion] The study provided theoretical reference to the forecast in future. 展开更多
关键词 RAINSTORM Dry air intrusion South area of shaanxi China
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Analysis of Meteorological Conditions of Freeze Damage to Citrus in Southern Shaanxi in the Winter of 2010 and Defensive Countermeasures 被引量:4
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作者 柏秦凤 王景红 +3 位作者 霍治国 梁轶 张维敏 郭民主 《Agricultural Science & Technology》 CAS 2013年第3期444-449,共6页
In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investig... In order to take advantage of the climate resources more effectively ac- cording to the local circumstances and to plan and develop the citrus industry in Southern Shaanxi more reasonably. On the basis of the investigation of freeze dam- age to citrus occurring in Southern Shaanxi in the winter of 2010, the climatic back- ground for the formation of this freeze damage was analyzed. In combination with the freeze damage indicators during the overwintering period and the harmful accu- mulated cold during the cold wave, indexes for grading the freeze damage in southern Shaanxi were analyzed and verified, and the perspective of grading the freeze damage using the harmful accumulated cold during the cold wave was also presented. Through analyzing the extremely lowest temperature and the harmful ac- cumulated cold in the winter of 2010 and in history at 12 citrus growing counties (districts) in Ankang area and Hanzhong area, the reasons why the freeze damage to citrus during the overwintering period was severer in the west than in the east of Southern Shaanxi were discussed, and the results obtained were basically consistent with the actual situation observed from investigation. Finally, defensive countermea- sures against the freeze damage to citrus during the overwintering period were put forward from several aspects. 展开更多
关键词 CITRUS Southern shaanxi Freeze damage during the overwintering peri- od Meteorological conditions Defensive countermeasures
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Effect of Different Land Use Patterns on Physical Properties of Soil Water in Yellow River Wetland in Shaanxi Province 被引量:2
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作者 刘云鹏 张社奇 +1 位作者 谷洁 解迎革 《Agricultural Science & Technology》 CAS 2010年第9期148-152,共5页
[Objective] This study was to reveal the effect of different land use patterns on physical characteristics of soil water in the Yellow River wetland in Shaanxi Province.[Method]Taking Yellow River wetland in Shaanxi P... [Objective] This study was to reveal the effect of different land use patterns on physical characteristics of soil water in the Yellow River wetland in Shaanxi Province.[Method]Taking Yellow River wetland in Shaanxi Province as experimental plot,we compared the physical properties of the soil water under different land use patterns and studied the physical properties and the change law of soil water during the wetland degeneration process.[Result]Under different land use patterns,soil bulk density rose with the increase of soil depth.During the degeneration process of from river wetland to reclaimed wetland(paddy field),finally to abandoned land owing to salinization,the mean soil bulk density reduced correspondingly from 1.474 to 1.522 g/cm3,finally to 1.593 g/cm3 when abandoned.Accompanying wetland degeneration,soil became compact increasingly,and the indicators of soil porosity(total porosity,capillary porosity,non-capillary porosity)were also reduced with the change of land use patterns,in which,capillary porosity and total porosity reached the extremely significant level with the change of land use patterns,and non-capillary porosity reached significant level.The changes of soil porosity condition accelerated the deterioration of wetland.Under different land use patterns,the maximum soil moisture capacity,capillary moisture capacity and minimum moisture capacity all showed a similar change law.Compared with wetland,the maximum soil moisture capacity of reclaimed land(paddy field)and salinized land respectively decreased by 5.7% and 22.3%,capillary moisture capacity by 0.2% and 19.4%,minimum moisture capacity by 2.7% and 15.9%.Of the three land use patterns,wetland displayed both higher water holding capacity and water drainage capacity over reclaimed land(paddy field)and salinized land.By comparison with wetland,the reclaimed land(paddy field)and salinized land respectively decreased by 12.4% and 15.2% in total water holding capacity,and by 2.7% and 15.9% in total water drainage capacity.[Conclusion]To conserve the water resource in Yellow River wetland,regulate the hydrological cycle and enhance drought and water logging resistances,it should be noted that reasonable countermeasures be taken to exploit the state-owned forest land and paddy field around the wetland and the related resources. 展开更多
关键词 Yellow River wetland in shaanxi Land use pattern Soil bulk density Water holding capacity Water drainage capacity
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Exploration of Eco-economic Development in Ecological Fragile Region——A Case Study on Wuqi County in Shaanxi Province 被引量:1
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作者 张冰 王冬 《Agricultural Science & Technology》 CAS 2012年第7期1524-1531,共8页
[Objective] The aim was to explore eco-economy in ecological fragile region with Wuqi County in Shaanxi Province as an example. [Method] Eco-economy development and major environmental problems in Wuqi County in Shaan... [Objective] The aim was to explore eco-economy in ecological fragile region with Wuqi County in Shaanxi Province as an example. [Method] Eco-economy development and major environmental problems in Wuqi County in Shaanxi Province were researched based on local social and economic conditions, population of impoverished people and environment vulnerability. [Result] The areas with vulnerable environment and backward economy should establish a virtuous circle between economy and environment and a sustainable model of economic development. [Conclusion] It is significant to change the severe situation of environment deterioration and to promote ecological civilization. 展开更多
关键词 Ecological fragile region Ecological economy Environment protection Virtuous circle Wuqi County in shaanxi Province
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A New Species of the Genus Chorthippus (Orthoptera: Arcypteridae) from North of Shaanxi, China 被引量:1
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作者 王延峰 郑哲民 《Entomotaxonomia》 CSCD 北大核心 2006年第1期17-20,共4页
In this paper, a new species of the genus Chorthippus is described from North of Shaanxi Province, China, namely: Chorthippus wuqiensis sp. nov. The type specimens are deposited in the Institute of Zoology, Shaanxi N... In this paper, a new species of the genus Chorthippus is described from North of Shaanxi Province, China, namely: Chorthippus wuqiensis sp. nov. The type specimens are deposited in the Institute of Zoology, Shaanxi Normal University. 展开更多
关键词 Onhoptera ACRIDOIDEA ARCYPTERIDAE CHORTHIPPUS new species North of shaanxi Province China
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Analysis of the Current Situation of Drug Clinical Trial Institutions in Shaanxi Province
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作者 Yurong Zhang Qi Zhang +4 位作者 Li Wang Rui Xu Lili Zhao Enze Li Xin Wang 《Journal of Clinical and Nursing Research》 2024年第1期78-87,共10页
To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on... To understand the current situation of institutional registration in Shaanxi Province after the implementation ofregistration system management in drug clinical trial institutions.Relevant information was collected on the“Announcement on the Accreditation of Drug Clinical Trial Institutions”issued by the National Medical Products Administration from 2005 to August 2022,the record management information system of drug and medical device clinical trial institutions,and the drug clinical trial registration and information publicity platform.A retrospective analysis was carried out in terms of institutional development,regional distribution,registered majors,principal investigators,and the number of drug clinical trials.After the implementation of institution registration,the number of drug clinical trial institutions in Shaanxi Province increased by 47.4%,884 principal investigators were registered,the number of registered majors expanded from 58 qualified to 117,and the professional scope increased by 50.4%.The policy of institution registration is conducive to promoting the rational use of medical resources and the development of drug clinical trial institutions and improving the healthy development of the pharmaceutical industry in Shaanxi Province. 展开更多
关键词 Drug clinical trial Institution registration Registered majors Current situation analysis Professional group shaanxi Province
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Rural Tourism Development Strategies of Shaanxi Province in North China 被引量:1
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作者 丁华 岳丹 董风 《Journal of Landscape Research》 2011年第8期70-73,81,共5页
Rural tourism development in Shaanxi Province is introduced:largely improved with a fast speed; large quantity of rural tourist sites covering a great range, a complete product system; more and more investment; new pr... Rural tourism development in Shaanxi Province is introduced:largely improved with a fast speed; large quantity of rural tourist sites covering a great range, a complete product system; more and more investment; new progress in the construction of management system and guarantee system; progress in the construction of new countryside. Development advantages and opportunities of rural tourism industry in Shaanxi Province are analyzed: rich humanistic, natural and agricultural resources are inborn advantages of its rural tourism development; excellent location and increasing GDP per capita provides more market opportunities for rural tourism development; prospering tourism industry provides an excellent exterior environment for rural tourism development; a complete traffic network facilitates rural tourism development. Then development strategies for the rural tourism industry of Shaanxi Province are given:government should be a guider, planning should be accelerated, layouts reasonably designed, rural tourism development concepts clarified; brands should be created to drive the overall development by using several prominent scenic spots and promote the scale-development of rural tourism industry; the core strategy is to launch concrete programs and promote rural tourism development; publicity should be enhanced to make the good reputation of rural tourism more popular; standard regulations should be made, special staff trained for rural tourism services and the system of "farm-stay" association improved. 展开更多
关键词 shaanxi PROVINCE RURAL TOURISM Development STRATEGIES
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Analysis of Heavy Metal Content in Food Crops Planted Along the Shaanxi Inner Mongolia Expressway 被引量:2
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作者 艾海舰 张雄 +2 位作者 刘翠英 纪晓玲 卜耀军 《Agricultural Science & Technology》 CAS 2009年第3期108-111,119,共5页
To understand the effect of the running of Shaanxi Inner Mongolia Expressway on food crops planted along the sides, we determined the heavy metal contents(Zn, Pb, Cu and Cb) in the digestion solutions of the root, ste... To understand the effect of the running of Shaanxi Inner Mongolia Expressway on food crops planted along the sides, we determined the heavy metal contents(Zn, Pb, Cu and Cb) in the digestion solutions of the root, stem and leaf from rice and corn. The results showed that highway promoted the accumulation of heavy metal elements in corn and rice. Compared with the CKs(crops produced where no highway extend), contents of heavy metal elements in two crops tested from two sampling sites were both over standard. This indicates that food crops planted within 100 m away from the highway are been polluted by heavy metals, which is directly related with the running of Shaanxi Inner Mongolia Expressway. Based on this, the areas within 100 m away from the highway are not suggested to cultivate food crops. 展开更多
关键词 shaanxi Inner Mongolia Expressway Food crop Heavy metal
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Changes in Ecosystem Service Values on the Loess Plateau in Northern Shaanxi Province,China 被引量:9
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作者 LI Jing REN Zhi-yuan 《Agricultural Sciences in China》 CAS CSCD 2008年第5期606-614,共9页
The Loess Plateau in northern Shaanxi Province of China covers Yulin, Yan'an, and Tongchuan cities mainly. The kind of physiognomy is complicated and various, including the transitional region of the sand and wind, t... The Loess Plateau in northern Shaanxi Province of China covers Yulin, Yan'an, and Tongchuan cities mainly. The kind of physiognomy is complicated and various, including the transitional region of the sand and wind, the hilly-gully fragile region, the pimple mound region from North to South. Large-scale land reclamation projects that are severely affecting these ecosystems have been implemented. In this paper, we reported an investigation to the changes in land use and ecosystem services on the Loess Plateau in northern Shaanxi Province from 1978 to 2000. We used three LANDSAT TM and/or ETM data sets to estimate the changes in the size of five land-cover/land-use categories, and we also used previously published value coefficients to estimate the changes in the value of ecosystem services delivered by each land category. Finally, we ranked the contribution of various ecosystem functions to the overall value of the ecosystem services, we have estimated that the annual value of the ecosystem services is 56.95 billon RMB yuan in the Loess Plateau in northern Shaanxi Province in 2000. In the region, from 1978 to 2000, the economic value of the fixing carbon was higher, the economic value of water conservation was the lowest, but the economic value of the NPP, fixing carbon, and supplying oxygen accounted for above ninety percent of the total value, obviously the vegetation created the biggest ecosystem service value. We can conclude that future land-use policy formulation should give precedence to the conservation of these ecosystems over uncontrolled reclamation, and that further land reclamation should be based on rigorous environmental impact analyses. 展开更多
关键词 LANDUSE ecosystem services the value ecosystem functions the Loess Plateau northern shaanxi Province
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Construction of Monastery Garden Landscapes in Northern Shaanxi Province of China 被引量:1
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作者 张颖 商铁林 《Journal of Landscape Research》 2011年第4期13-16,21,共5页
In view of the present construction of monastery garden landscapes in northern Shaanxi,landscape features were pointed out as:harsh natural environment of monastery garden,dual functions of religion and tourism,large ... In view of the present construction of monastery garden landscapes in northern Shaanxi,landscape features were pointed out as:harsh natural environment of monastery garden,dual functions of religion and tourism,large spatial capacity of architectural complex,long history and profound cultures,and also working as botanic gardens.Problems in these monastery gardens were proposed as:poor overall landscaping design,insufficient plants of religious cultures,lacking in artistic plant furnishings showing ornamental effects and seasonal aspects of plants,plant furnishings failed to show cultural characteristics of northern Shaanxi,poor diversity and improper ratio of plant furnishings,attaching insufficient importance to vertical greening,similar plant communities.On the basis of investigating characteristics and problems of monastery garden landscapes in northern Shaanxi,layouts and plant furnishings of incense roads,religious sectors and living sectors in those gardens were analyzed,suitable plant species were given as references,so as to explore new landscape modes of "human-nature oneness" and provide useful experience for the landscape construction of monastery gardens in Shaanxi. 展开更多
关键词 NORTHERN shaanxi MONASTERY GARDEN LANDSCAPE CONSTRUCTION
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A New Species of Simulium (Diptera: Simuliidae) from Shaanxi, China 被引量:2
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作者 刘增加 安继尧 《Entomotaxonomia》 CSCD 北大核心 2009年第2期143-146,共4页
Simulium (Simulium) liubaense, sp. nov. is described based on the female specimens collected from Liuba, Shaanxi Province, China. This species is assigned to the variegotum-group of the subgenus Simulium, and is clo... Simulium (Simulium) liubaense, sp. nov. is described based on the female specimens collected from Liuba, Shaanxi Province, China. This species is assigned to the variegotum-group of the subgenus Simulium, and is closely related to S. (S.)jingfui Cai and An, 2008, S. (S.) taiwanicum Takaoka, 1979, S. (S.) hackeri Edwards 1928, S. (S.) chamlongi Takaoka and Suzuki, 1984. However it is clearly differentiated from them by the structure of cibarium, genital fork, genital plate, paraproct and cercus of the female. All the specimens are kept in the Medical Entomology Collection Gallery, Academy of Military Medical Sciences, Beijing. 展开更多
关键词 DIPTERA SIMULIIDAE SIMULIUM Simulium (Simulium) new species shaanxi Province China
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Quantitative analysis of the dynamic change and spatial differences of the ecological security: a case study of Loess Plateau in northern Shaanxi Province 被引量:5
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作者 LI Jing REN Zhiyuan ZHOU Zixiang 《Journal of Geographical Sciences》 SCIE CSCD 2006年第2期251-256,共6页
Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecologica... Using the theory and method of the ecological footprint, and combining the changes of regional land use, resource environment, population, society and economy, this paper calculated the ecological footprint, ecological carrying capacity and ecological surplus/loss in 1986-2002 on the Loess Plateau in northern Shaanxi Province. What is more, this paper has put forward the concept of ecological pressure index, set up ecological pressure index models, and ecological security grading systems, and the prediction models of different ecological footprints, ecological carrying capacity, ecological surplus and ecological safety change, and also has assessed the ecological footprint demands of 10,000 yuan GDE The results of this study are as follows: (1) the ecological carrying capacity in northern Shaanxi shows a decreasing trend, the difference of reducing range is the fastest; (2) the ecological footprint appears an increasing trend; (3) ecological pressure index rose to 0.91 from 0.44 during 1986-2002 on the Loess Plateau of northern Shaanxi with an increase of 47%; and (4) the ecological security in the study area is in a critical state, and the ecological oressure index has been increasing rapidlv. 展开更多
关键词 regional ecological security dynamic change spatial difference quantitative analysis the Loess Plateau in northern shaanxi Province
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New Thought of Meteorological Forecasting and Warning Models of Geological Disasters in Loess Plateau of North Shaanxi
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作者 高维英 李明 +1 位作者 杜继稳 王雁林 《Meteorological and Environmental Research》 CAS 2010年第8期12-16,共5页
The study established daily comprehensive precipitation equations and calculated respective critical daily comprehensive precipitation value of loess-collapse disasters and landslide disasters by dint of the geologica... The study established daily comprehensive precipitation equations and calculated respective critical daily comprehensive precipitation value of loess-collapse disasters and landslide disasters by dint of the geological disasters and corresponding precipitation data in 47 years.Considering geological disaster risk divisions,precipitation influence coefficient and daily comprehensive precipitation,hourly rolling daily-forecasting and hourly warning fine and no-gap models on the base of high temporal and spatial resolution rainfall data of automatic meteorological station were developed.Through the verifying of combination of dynamical forecasting model and warning model,the results showed that it can improve efficiency of forecast and have good response at the same time. 展开更多
关键词 Loess Plateau of North shaanxi Geological disasters Daily comprehensive precipitation Forecasting and warning models China
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Oil/Gas Accumulation Characteristics and Exploration Methods of the Deltaic Lithologic Reservoirs in Northern Shaanxi Area 被引量:4
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作者 YangHua FuJinhua YuJian DuJinliang MuJingkui 《Petroleum Science》 SCIE CAS CSCD 2004年第2期69-78,共10页
There are large deltaic systems in the Triassic Yanchang Formation in the northern Shaanxi area of the Ordos Basin, and developed two sets of good source-reservoir-caprock assemblages and many sets of oil-bearing beds... There are large deltaic systems in the Triassic Yanchang Formation in the northern Shaanxi area of the Ordos Basin, and developed two sets of good source-reservoir-caprock assemblages and many sets of oil-bearing beds. Exploration experience demonstrates that the formation and distribution of the reservoir were controlled by the generative depression of the Yanchang Formation, and deltaic reservoir sand body is the material basis for large-scale oilfields. In addition, secondary laumontite in a low permeable area was dissolved and then a high permeable area was formed. The updip lithologic variety of reservoir sand bodies is favorable to the formation of subtle lithologic traps, and the deltaic reservoirs are characterized by large multi-beds of oil-generation and abundant hydrocarbon resources. In this paper, the petroleum geologic settings of the studied area are analyzed, and the accumulation characteristics and exploration methods of lithologic reservoirs are summarized. It is of theoretical significance for the study of the exploration theories of lithologic reservoirs, and also expedites the exploration steps of deltaic reservoirs in the northern Shaanxi area. 展开更多
关键词 Northern shaanxi area sedimentary cycle deltaic sand body laumontite solution pore subtle reservoir exploration method
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Existing Problems in Energy Exploitation and Eco-environment Sustainable Development and Their Countermeasures in Northern Shaanxi 被引量:4
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作者 GUO Jun-quan1, YANG Zhi-guo2 1. Department of Agriculture and Forestry Architecture, Yan’an Vocational and Technical College, Yan’an 716000, China 2. Yanan Municipal Environmental Protection Monitoring Station, Yan’an 716000, China 《Meteorological and Environmental Research》 CAS 2011年第4期76-78,共3页
The exploitation of coal, petroleum and natural gas in northern Shaanxi not only promoted the rapid development of economy, but also brought about enormous pressure to fragile ecology and resulted to severe water poll... The exploitation of coal, petroleum and natural gas in northern Shaanxi not only promoted the rapid development of economy, but also brought about enormous pressure to fragile ecology and resulted to severe water pollution, water and soil loss, vegetation destruction and other ecological environmental problems, so many countermeasures were put forward according to these problems, such as greatly developing circular economy, conducting cleaner production in petroleum enterprises, continuously renewing mining technology and so on. 展开更多
关键词 Ecological environment Sustainable development Water pollution Circular economy Northern shaanxi China
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Division of diagenesis reservoir facies and its control——Case study of Chang-3 reservoir in Yangchang formation of Fuxian exploration area in northern Shaanxi 被引量:6
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作者 FU Guo-min QIN Xiao-li +2 位作者 MIAO Qing ZHANG Tian-jin YANG Jian-peng 《Mining Science and Technology》 EI CAS 2009年第4期537-543,共7页
By dividing the diagenetic reservoir facies and studying its distribution,we can effectively evaluate reservoirs.Using an analytical method for mutual relationships among diagenesis of reservoirs,structural characteri... By dividing the diagenetic reservoir facies and studying its distribution,we can effectively evaluate reservoirs.Using an analytical method for mutual relationships among diagenesis of reservoirs,structural characteristics and the origin of types of sand,we classified the diagenetic reservoir of the Yanchang formation Chang-3 oil layer into different types and analyzed the factors controlling this high quality reservoir.The results show that:1) the catagenesis of the Chang-3 oil layer in the Fuxian region is complex and variable;2) mechanical compaction,pressure solutions and cementation of all kinds of authogenous minerals decreases porosity by 28.13% and 3) corrosion increases porosity by 3.39%.Cementation and corrosion of laumontite is a kind of catagenesis which makes this region different from other exploratory regions.The original amount and rate of corrosion of laumontite are the main factors for the increase in laumontite porosity.The Chang-3 oil layer developed four kinds of diagenetic reservoir facies,of which the weak compaction facies,i.e.,laumontite corrosion and overgrowth,of the original pore reservoir facies has the most promising diagenesis.Its distribution is controlled by a sedimentary facies zone and is widely developed in the original truncated tributary channel facies belt of the delta plain.The development of this high quality reservoir is controlled by the distribution of sedimentary sand bodies and secondarily-eroded porosity of laumontite in the Chang-3 oil layer of the Fuxian exploratory region. 展开更多
关键词 DIAGENESIS LAUMONTITE diagenetic facies Yanchang formation northern shaanxi province
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Potash–Forming Regularity of the Ordovician Marine Northern Shaanxi Salt Basin: Insight from Review and Prospect of the Deep Geology of the Ordos Basin 被引量:1
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作者 WANG Zhentao ZHENG Mianping 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第4期1627-1644,共18页
The Ordovician Northern Shaanxi Salt Basin (ONSSB), located in the east-central Ordos Basin, western North China Craton (NCC), is one of the largest marine salt basins yet discovered in China. A huge amount of hal... The Ordovician Northern Shaanxi Salt Basin (ONSSB), located in the east-central Ordos Basin, western North China Craton (NCC), is one of the largest marine salt basins yet discovered in China. A huge amount of halite deposited in the Mid-Ordovician Majiagou Formation, and potash- containing indication and local thin layer of potash seam were discovered in O2m^65 (6th submember, 5th member of the Majiagou Formation). This makes ONSSB a rare Ordovician potash-containing basin in the world, and brings new hope for prospecting marine solid potash in this basin. However, several primary scientific problems, such as the coupling relationship between ONSSB and the continent nucleus, how the high-precision basement fold controls the ONSSB, and how the basement faults and relief control ONSSB, are still unclear due to the limitations of the knowledge about the basement of the Ordos Basin. This has become a barrier for understanding the potash-forming regularity in the continental nucleus (CN) area in marine salt basin in China. Up to now, the material accumulation has provided ripe conditions for the answers to these questions. Latest zircon U-Pb ages for the basement samples beneath the Ordos Basin reveal that there exists a continental nucleus (Yi-Meng CN) beneath the northern Ordos Basin. And this brings light into the fact that the ONSSB lies not overlying on the Yi- Meng CN but to south Yi-Meng CN. Both do not have superimposed relationship in space. And borehole penetrating into the basement reached Palaeoproterozoic meta-sedimentary rocks, which suggests the ONSSB is situated in the accretion belt of Yi-Meng CN during geological history. Basement relief beneath the ONSSB area revealed by seismic tomography and aeromagnetic anomaly confirms the existence of basement uplift and faults, which provides tectonic setting for sedimentary center migration of the ONSSB. Comparative research with various data sources indicates that the expanding strata in the ONSSB adopted the shape of the basement folds. We found that the orientations of the potash sags showed high correlation with those of several basement and sedimentary cover faults in the ONSSB. The secondary depressions are also controlled by the faults. Comparative research between all the global salt basins and continental nuclei distribution suggests that distribution of the former is controlled by the latter, and almost all the salt basins developed in or at the margin of the continental nucleus area. The nature of the tectonie basement exerts a key controlling effect on potash basin formation. And on this basis we analyzed in detail the geological conditions of salt-forming and potash-forming in the ONSSB. 展开更多
关键词 Ordos Basin Northern shaanxi Salt Basin continental nucleus aeromagnetic anomaly coupling relationship
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Change Characteristics and Cause Analysis of Summer Precipitation Anomaly in Loess Plateau of Northern Shaanxi Province 被引量:1
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作者 Qiang Li Zhicai Li +1 位作者 Xiaoli Li Tao Liu 《Meteorological and Environmental Research》 CAS 2013年第2期5-7,11,共4页
[ Objective] The research aimed to study change characteristics and formation cause of summer precipitation abnormality in Loess Plateau of northern Shaanxi Province. [ Method] Based on summer precipitation data at 15... [ Objective] The research aimed to study change characteristics and formation cause of summer precipitation abnormality in Loess Plateau of northern Shaanxi Province. [ Method] Based on summer precipitation data at 15 observation stations in Loess Plateau of northern Shaanxi Province and NCEP/NCAR dataset from 1961 to 2008, change characteristics of summer precipitation in the region were investigated by using linear trend estimation and composite analysis. [Result] Summer rainfall had decrease trend in most parts of northem Shaanxi Province, but had increase trend in western and southern regions. The interannual and interdecadal variations were obvious. It had a large amount of precipitation from the mid- 1970s to the mid-1990s, while summer rainfall had decrease trend after the mid-1990s and increase trend in recent years. In wet years, it was a large positive anomaly zone from western Ural Mountains to northem Lake Baikal at middle and high latitudes, indicating that there was a blocking high over the Ural Mountains, while it was negative anomaly zone from northern Okhotsk Sea to Lake Baikal. From Northwest Pacific Ocean to Bo- hal Sea Bay and North China, it was a wide range of significant positive anomaly zone, which was favorable for Westem Pacific subtropical high ex- tending westward and northward. The analysis in dry years showed opposite circulation configuration. It was " -, +, -" wave train distribution in middle and high latitudes and positive anomaly zone along the Sea of Okhotsk. Western Pacific subtropical high was also by south and east. Major water vapor was from southeast direction in wet years, and abundant water vapor caused more summer rainfall in northern Shaanxi. In dry years, water vapor was from westerly tuming southerly flow. It was weaker and by east. [ Conclusion] The research provided reference for reasonable utilization of summer precipitation in the zone. 展开更多
关键词 Loess Plateau Northern shaanxi Province Summer precipitation ABNORMALITY China
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New Discovery of Reproductive Organs and Spores in Situ of Ginkgoales and Czekanowskiales from the Middle Jurassic of Shaanxi, China 被引量:1
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作者 GUO Caiqing YAO Jianxin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第6期2314-2315,共2页
Objective Ginkgoales and Czekanowskiales are important components of Mesozoic flora and were widely distributed in the Northern Hemisphere. They are usually preserved together in the stratum. Their fossils are abunda... Objective Ginkgoales and Czekanowskiales are important components of Mesozoic flora and were widely distributed in the Northern Hemisphere. They are usually preserved together in the stratum. Their fossils are abundant in the Middle Jurassic of Shaanxi Province, but there are no reports on their reproductive organs. Here, we report two male gymnospermous pollen cones from the Middle Jttrassic Yan'an Formation of the northeast Yulin City, Shaanxi Province, China. The characteristics of the fossils, including those of pollens, have been described in detail. The new specimens were compared with fossils closely similar in morphology, and the taxonomic affinity and systematies were established. The present results offer new fossil materials for the study of taxonomy, evolution, and phytogeography of Ginkgoales and Czekanowskiales. 展开更多
关键词 New Discovery of Reproductive Organs and Spores Situ of Ginkgoales Czekanowskiales from the Middle Jurassic of shaanxi
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